# Patent

## Title
Piperidine compounds for use as orexin receptor antagoinst

## Abstract

A invention relates to N aroyl cyclic amine derivatives and their use as pharmaceuticals, specifically as orexin receptor antagonists.

## Background
This invention relates to N-aroyl cyclic amine derivatives and their use as pharmaceuticals.
Many medically significant biological processes are mediated by proteins participating in signal transduction pathways that involve G-proteins and/or second messengers.
Polypeptides and polynucleotides encoding the human 7-transmembrane G-protein coupled neuropeptide receptor, orexin-1 (HFGAN72), have been identified and are disclosed in EP-A-875565, EP-A-875566 and WO 96/34877. Polypeptides and polynucleotides encoding a second human orexin receptor, orexin-2 (HFGANP), have been identified and are disclosed in EP-A-893498.
Polypeptides and polynucleotides encoding polypeptides which are ligands for the orexin-1 receptor, e.g. orexin-A (Lig72A) are disclosed in EP-A-849361.
Orexin receptors are found in the mammalian host and may be responsible for many biological functions, including pathologies including, but not limited to, depression; anxiety; addictions; obsessive compulsive disorder; affective neurosis/disorder; depressive neurosis/disorder; anxiety neurosis; dysthymic disorder; behaviour disorder; mood disorder; sexual dysfunction; psychosexual dysfunction; sex disorder; sexual disorder; schizophrenia; manic depression; delerium, dementia; severe mental retardation and dyskinesias such as Huntington's disease and Gilles de la Tourett's syndrome; disturbed biological and circadian rhythms; feeding disorders, such as anorexia, bulimia, cachexia, and obesity; diabetes; appetite/taste disorders; vomiting/nausea; asthma; cancer; Parkinson's disease; Cushing's syndrome/disease; basophil adenoma; prolactinoma; hyperprolactinemia; hypopituitarism; hypophysis tumor/adenoma; hypothalamic diseases; Froehlich's syndrome; adrenohypophysis disease; hypophysis disease; hypophysis tumor/adenoma; pituitary growth hormone; adrenohypophysis hypofunction; adrenohypophysis hyperfunction; hypothalamic hypogonadism; Kallman's syndrome (anosmia, hyposmia); functional or psychogenic amenorrhea; hypopituitarism; hypothalamic hypothyroidism; hypothalamic-adrenal dysfunction; idiopathic hyperprolactinemia; hypothalamic disorders of growth hormone deficiency; idiopathic growth hormone deficiency; dwarfism; gigantism; acromegaly; and sleep disturbances associated with such diseases as neurological disorders, neuropathic pain and restless leg syndrome, heart and lung diseases; acute and congestive heart failure; hypotension; hypertension; urinary retention; osteoporosis; angina pectoris; myocardial infarction; ischaemic or haemorrhagic stroke; subarachnoid haemorrhage; head injury such as sub-arachnoid haemorrhage associated with traumatic head injury; ulcers; allergies; benign prostatic hypertrophy; chronic renal failure; renal disease; impaired glucose tolerance; migraine; hyperalgesia; pain; enhanced or exaggerated sensitivity to pain, such as hyperalgesia, causalgia and allodynia; acute pain; burn pain; a typical facial pain; neuropathic pain; back pain; complex regional pain syndromes I and II; arthritic pain; sports injury pain; pain related to infection, e.g. HIV, post-polio syndrome, and post-herpetic neuralgia; phantom limb pain; labour pain; cancer pain; post-chemotherapy pain; post-stroke pain; post-operative pain; neuralgia; nausea and vomiting; conditions associated with visceral pain including irritable bowel syndrome, migraine and angina; urinary bladder incontinence e.g. urge incontinence; tolerance to narcotics or withdrawal from narcotics; sleep disorders; sleep apnea; narcolepsy; insomnia; parasomnia; jet-lag syndrome; and neurodegencrative disorders, which includes nosological entities such as disinhibition-dementia-parkinsonism-amyotrophy complex; pallido-ponto-nigral degeneration, epilepsy, and seizure disorders.
Experiments have shown that central administration of the ligand orexin-A (described in more detail below) stimulated food intake in freely-feeding rats during a 4 hour time period. This increase was approximately four-fold over control rats receiving vehicle. These data suggest that orexin-A may be an endogenous regulator of appetite. Therefore, antagonists of its receptor may be useful in the treatment of obesity and diabetes, see Cell, 1998, 92, 573-585.
There is a significant incidence of obesity in westernised societies. According to WHO definitions a mean of 35% of subjects in 39 studies were overweight and a further 22% clinically obese. It has been estimated that 5.7% of all healthcare costs in the USA are a consequence of obesity. About 85% of Type 2 diabetics are obese, and diet and exercise are of value in all diabetics. The incidence of diagnosed diabetes in westernised countries is typically 5% and there are estimated to be an equal number undiagnosed. The incidence of both diseases is rising, demonstrating the inadequacy of current treatments which may be either ineffective or have toxicity risks including cardiovascular effects. Treatment of diabetes with sulfonylureas or insulin can cause hypoglycaemia, whilst metformin causes GI side-effects. No drug treatment for Type 2 diabetes has been shown to reduce the long-term complications of the disease. Insulin sensitisers will be useful for many diabetics, however they do not have an anti-obesity effect.
Rat sleep/EEG studies have also shown that central administration of orexin-A, an agonist of the orexin receptors, causes a dose-related increase in arousal, largely at the expense of a reduction in paradoxical sleep and slow wave sleep 2, when administered at the onset of the normal sleep period. Therefore antagonists of its receptor may be useful in the treatment of sleep disorders including insomnia.
The present invention provides N-aroyl cyclic amine derivatives which are non-peptide antagonists of human orexin receptors, in particular orexin-1 receptors. In particular, these compounds are of potential use in the treatment of obesity, including obesity observed in Type 2 (non-insulin-dependent) diabetes patients, and/or sleep disorders. Additionally these compounds may be of use in the treatment of stroke, particularly isohemic or haemorrhagic stroke, and/or blocking the emetic response i.e. the compounds are useful in the treatment of nausea and vomiting.
International Patent Applications WO99/09024, WO99/58533, WO00/47577 and WO00/47580 disclose phenyl urea derivatives and WO00/47576 discloses quinolinyl cinnamide derivatives as orexin receptor antagonists.
According to the invention there is provided a compound of formula (I):




wherein:
X represents a bond, oxygen, NR3 or a group (CH2)n, wherein n represents 1, 2 or 3,
Y represents CH2, CO, CHOH, or —CH2CH(OH)—;
Het is an optionally substituted 5- or 6-membered monocyclic heteroaryl group containing up to 4 heteroatoms selected from N, O and S, substituted by R2;
Ar2 represents an optionally substituted phenyl or a 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected from N, O and S, wherein the phenyl or heteroaryl group is substituted by R1 and further optional substituents; or Ar2 represents an optionally substituted bicyclic aromatic or bicyclic heteroaromatic group containing up to 3 heteroatoms selected from N, O and S;
R1 represents hydrogen, an optionally substituted(C1-4)alkoxy, halo, cyano, optionally substituted(C1-6)alkyl, optionally substituted phenyl, or an optionally substituted 5- or 6-membered heterocyclyl group containing up to 4 heteroatoms selected from N, O and S;
R2 is an optionally substituted aryl or an optionally substituted mono or bicyclic heteroaryl group containing up to 3 heteroatoms selected from N, O and S;
R3 is selected from hydrogen or (C1-4)alkyl;
or a pharmaceutically acceptable salt thereof.
A further aspect of the invention is the compound (RS)-1-dibenzofuran-4-yl-1-{2-[5-(3-fluoro-phenyl)[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone or a pharmaceutically acceptable salt thereof.
Preferably where Ar2 represents phenyl or a 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected from N, O and S, the R1 group is situated adjacent to the point of attachment to the amide carbonyl.
Het may have up to 5, preferably 1, 2 or 3 optional substituents.
When Het is an optionally substituted 5- or 6-membered monocyclic heteroaryl group containing up to 4 heteroatoms selected from N, O and S, it may be oxazolyl, imidazolyl, thiazolyl, thiadiazolyl, oxadiazolyl, triazolyl, pyrazolyl, furanyl, tetrazolyl, pyrimidinyl, pyrazinyl, pyridazinyl or pyridinyl. Additionally Het may be isoxazolyl, isothiazolyl and triazinyl.
Prefered examples for Het are oxazolyl, imidazolyl, thiazolyl, triazolyl, oxadiazolyl and pyrazolyl. Additional prefered examples are furanyl and tetrazolyl.
When Ar2 is a 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected from N, O and S, it may be furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, triazinyl, pyridazinyl, pyridinyl, pyrimidinyl, isothiazolyl, isoxazolyl, pyrazinyl, or pyrazolyl.
Alternatively, examples of Ar2 are thiazolyl, pyrazolyl, triazolyl, pyridazinyl, oxazolyl, pyridinyl, pyrimidinyl, isoxazolyl and thienyl.
More specifically, examples of Ar2 are thiazolyl, pyrazolyl, triazolyl, pyridazinyl, oxazolyl, pyridinyl, pyrimidinyl, and thienyl.
When R1 is an optionally substituted 5- or 6-membered heterocyclyl group containing up to 4 heteroatoms selected from N, O and S, it may be furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, triazolyl, triazinyl, pyridazinyl, pyrimidinyl, isothiazolyl, isoxazolyl, pyrazinyl or pyrazolyl. Alternatively R1 can be piperidinyl, morpholinyl, thiomorpholinyl and piperazinyl. Additionally R1 can be tetrazolyl.
Preferably R1 is an optionally substituted 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected from N, O and S.
Examples of where Ar2 represents an optionally substituted bicyclic aromatic or bicyclic heteroaromatic include naphthyl, quinolinyl, napththyridinyl, benzofuranyl, benzimidazolyl, quinoxalinyl or quinazolinyl. Additionally Ar2 can be benzothienyl, benzotriazolyl, benzoxazolyl or indazolyl. Furthermore Ar2 can be isoquinolinyl.
When R2 is a mono or bicyclic heteroaryl group containing up to 3 heteroatoms selected from N, O and S, it can be, for example, benzofuranyl, pyrimidinyl, pyridinyl, pyridazinyl or furanyl.
Preferably Ar2 represents optionally substituted phenyl, pyridinyl, thiazolyl, pyrazolyl, pyridazinyl, thienyl, benzofuranyl, naphthyl or triazolyl.
Alternatively Ar2 represents optionally substituted phenyl, pyridinyl, thiazolyl, pyrazolyl, pyridazinyl, thienyl, benzofuranyl, naphthyl or 1,2,3-triazolyl.
X is preferably a bond, oxygen, or (CH2)n wherein n is 1 or 2.
Y is preferably CH2.
Alternatively R1 represents hydrogen, an optionally substituted(C1-4)alkoxy, halo, optionally substituted(C1-6)alkyl, optionally substituted phenyl, or an optionally substituted 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected fromn N, O and S
Furthermore R1 can represent an optionally substituted(C1-4)alkoxy, halo, optionally substituted(C1-6)alkyl, optionally substituted phenyl, or an optionally substituted 5- or 6-membered heteroaryl group containing up to 3 heteroatoms selected from N, O and S
Preferably R1 is selected from an optionally substituted phenyl, pyridinyl, pyrazolyl, pyrimidazinyl, or oxadiazolyl group.
Preferably R2 is attached to the atom in the monocyclic heteroaryl ring one removed from point of attachment of Het to the linker as shown in compound (I) of scheme 2a.
When used herein the term amide carbonyl means the —C(O)N bond wherein the N forms part of the cyclic amide ring
Even more preferably R1 represents an optionally substituted phenyl, or oxadiazolyl group.
Preferably R2 is an optionally substituted phenyl.
More preferably Het is oxadiazolyl, oxazolyl, imidazolyl, furanyl, thiazolyl or triazolyl, even more preferably Het is oxadiazolyl, oxazolyl, imidazolyl or furanyl.
Optional substituents for the groups Het, Ar2, R1 and R2 include halogen, hydroxy, oxo, cyano, nitro, (C1-4)alkyl, (C1-4)alkoxy, hydroxy(C1-4)alkyl, hydroxy(C1-4)alkoxy, halo(C1-4)alkyl, halo(C1-4)alkoxy, aryl(C1-4)alkoxy, (C1-4)alkylthio, hydroxy(C1-4)alkyl, (C1-4)alkoxy(C1-4)alkyl, (C3-6)cycloalkyl(C1-4)alkoxy, (C1-4)alkanoyl, (C1-4)alkoxycarbonyl, (C1-4)alkylsulfonyl, (C1-4)alkylsulfonyloxy, (C1-4)alkylsulfonyl(C1-4)allyl, arylsulfonyl, arylsulfonyloxy, arylsulfonyl(C1-4)alkyl, (C1-4)alkylsulfonamido, (C1-4)alkylamido, (C1-4)alkylsulfonamido(C1-4)alkyl, (C1-4)alkylamido(C1-4)alkyl, arylsulfonamido, arylcarboxamido, arylsulfonamido(C1-4)alkyl, (C1-4)arylcarboxamido(C1-4)alkyl, aroyl, aroyl(C1-4)alkyl, or aryl(C1-4)alkanoyl group; a group RaRbN-, RaOCO(CH2)r, RaCON(Ra)(CH2)r, RaRbNCO(CH2)r, RaRbNSO2(CH2)r or RaSO2NRb(CH2)r where each of Ra and Rb independently represents a hydrogen atom or a (C1-4)alkyl group or where appropriate RaRb forms part of a (C3-6)azacyloalkane or (C3-6)(2-oxo)azacycloalkane ring and r represents zero or an integer from 1 to 4. Additional substituents are (C1-4)acyl, aryl, aryl(C1-4)alkyl, (C1-4)alkylamino(C1-4)alkyl, RaRbN(CH2)n-, RaRbN(CH2)nO—, wherein n represents an interger from 1 to 4. Additionally when the substituent is RaRbN(CH2)n- or RaRbN(CH)nO, Ra with at least one CH2 of the (CH2)n portion of the group form a (C3-6)azacycloalkane and Rb represents hydrogen, a (C1-4)alkyl group or with the nitrogen to which it is attached forms a second (C3-6)azacycloalkane fused to the first (C3-6)azacycloalkane.
Preferred optional substituents for Ar2 are halogen, cyano, (C)4)alkyl, hydroxy(C1-4)alkyl, (C1-4)alkoxy(C1-4)alkyl, RaRbN(CH2)n, or RaRbN. Additionally prefered optional substituents are (C1-4)alkoxy, phenyl or nitro.
Preferred optional substituents for Het are halogen, cyano, or (C1-4)alkanoyl. Further optional substituents are hydroxy(C1-4)alkyl, (C1-4)alkyl, or CF3.
Preferred optional substituents for R1 are halogen, (C1-4)alkoxy(C1-4)alkyl, RaRbN, RaRbN(CH2)n and RaRbN(CH2)nO. Additional optional substituents are (C1-4)alkoxy, (C1-4)alkanoyl or C1-4)alkyl.
Preferred optional substituents for R1 are cyano, (C1-4)alkyl, (C1-4)alkoxy and halogen.
In addition Het may be optionally substituted by a phenyl ring optionally substituted by a halogen, cyano, C1-4aakyl, C1-4alkanoyl or C1-4alkylsulfonyl group; or by a 5- or 6-membered heterocyclic ring, such as a furanyl, pyridinyl, oxazolyl and pyrimidinyl. Additionally Het may be optionally substituted by a phenyl ring optionally substituted by (C1-4)alkoxy.
Preferred optional substituents for Ar2 include halogen, cyano, and (C1-4)alkyl.
In the groups Het and Ar2, substituents positioned ortho to one another may be linked to forms a ring.
Illustrative compounds of formula (I) can be selected from:













1
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone;


2
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone;


3
(RS)-1-[2-(3-Methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


4
(RS)-1-Naphthalen-1-yl-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-



methanone


5
(RS)-1-[2-(4-Fluoro-phenyl)-5-methyl-2H-pyrazol-3-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


6
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


7
(RS)-1-[4-(4-Fluoro-phenyl)-2-methyl-2H-pyrazol-3-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


8
(RS)-1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


9
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[2-(3-



methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone


10
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(3-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


11
(RS)-1-{2-[5-(3-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


12
(RS)-1-{2-[5-(3-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[2-(3-



methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone


13
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-pyridin-2-yl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


14
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


15
(RS)-1-{2-[5-(4-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


16
(RS)-1-{2-[5-(2-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


17
(RS)-1-{2-[5-(2-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[2-(3-



methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone


18
(RS)-1-{2-[5-(2,3-Dichloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


19
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


20
(RS)-1-[2-(5-Benzofuran-4-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


21
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(2-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


22
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-{2-[5-(2-fluoro-



phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


23
(RS)-1-{2-[5-(2-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-



naphthalen-1-yl-methanone


24
(RS)-1-{2-[5-(2,3-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


25
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


26
(RS)-1-{2-[5-(2,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


27
(RS)-1-{2-[5-(2,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1H-pyrazol-3-yl]-methanone


28
(RS)-1-{2-[5-(2,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


29
(RS)-1-{2-[5-(3,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


30
(RS)-1-{2-[5-(3,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-thiazol-4-yl]-methanone


31
(RS)-1-{2-[5-(3,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1H-pyrazol-3-yl]-methanone


32
(RS)-1-{2-[5-(3,5-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


33
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(6-methyl-pyridin-2-yl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


34
(RS)-1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-1-{2-[5-(6-methyl-pyridin-2-yl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


35
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(6-methyl-pyridin-2-



yl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


36
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-thiazol-4-yl]-methanone


37
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-furan-2-yl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


38
(RS)-1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-1-[2-(5-furan-2-yl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


39
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(5-furan-2-yl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


40
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-[2-(5-furan-2-yl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


41
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-thiazol-4-yl]-methanone


42
(RS)-1-[5-(3-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(3-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


43
(RS)-1-[5-(2-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(3-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


44
(RS)-1-[5-(4-Fluoro-phenyl)-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-



piperidin-1-yl]-methanone


45
(RS)-1-[5-(3-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


46
(RS)-1-[5-(2-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


47
(RS)-1-[5-(3-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(6-methyl-pyridin-2-yl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


48
(RS)-1-[5-(2-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(6-methyl-pyridin-2-yl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


49
(RS)-1-{2-[5-(2,3-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1H-pyrazol-3-yl]-methanone


50
(RS)-1-{2-[5-(2,3-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[4-



(4-fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


51
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-pyrrolidin-1-yl]-methanone


52
(RS)-1-[5-(3-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-pyrrolidin-1-yl]-methanone


53
(RS)-1-[5-(2-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-pyrrolidin-1-yl]-methanone


54
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(4-fluoro-phenyl)-oxazol-



2-ylmethyl]-piperidin-1-yl}-methanone


55
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(2-methoxy-phenyl)-



oxazol-2-ylmethyl]-piperidin-1-yl}-methanone


56
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(3-fluoro-phenyl)-oxazol-



2-ylmethyl]-piperidin-1-yl}-methanone


57
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(2-fluoro-phenyl)-oxazol-



2-ylmethyl]-piperidin-1-yl}-methanone


58
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-methyl-4-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


59
(RS)-2-(5-(4-Fluorophenyl)-furan-2-ylmethyl)-1-((5-(4-fluorophenyl)-2-methyl-thiazol-



4-yl)carbonyl-piperidine


60
(RS)-1-[2-(4-Fluoro-phenyl)-5-methyl-2H-pyrazol-3-yl]-1-[2-(4-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


61
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-[2-(4-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


62
(RS)-1-Naphthalen-1-yl-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone


63
(RS)-1-(5-Bromo-2-methoxy-phenyl)-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-



yl]-methanone


64
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-1H-imidazol-2-



ylmethyl)-piperidin-1-yl]-methanone


65
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-



[1,2,4]oxadiazol-5-ylmethyl]-piperidin-1-yl}-methanone


66
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(5-phenyl-[1,3,4]oxadiazol-2-



ylmethyl)-morpholin-4-yl]-methanone


67
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-oxazol-2-ylmethyl)-



morpholin-4-yl]-methanone


68
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-1H-imidazol-2-



ylmethyl)-morpholin-4-yl]-methanone


69
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-oxazol-



2-ylmethyl]-piperidin-1-yl}-methanone


70
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-oxazol-2-ylmethyl)-



piperidin-1-yl]-methanone


71
(RS)-1-{2-[5-(4-Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-naphthalen-1-yl-



methanone


72
(RS)-1-(3,5-Dimethoxy-phenyl)-1-{2-[5-(4-fluoro-phenyl)-oxazol-2-ylmethyl]-



piperidin-1-yl}-methanone


73
(RS)-1-[2-(4-Fluoro-phenyl)-5-methyl-2H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-



oxazol-2-ylmethyl]-piperidin-1-yl}-methanone


74
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-{2-[5-(4-fluoro-



phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-methanone


75
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-



oxazol-2-ylmethyl]-piperidin-1-yl}-methanone


76
(RS)-1-{2-[5-(4-Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-



phenyl)-thiazol-4-yl]-methanone


77
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-oxazol-2-ylmethyl)-



piperidin-1-yl]-methanone


78
(RS)-1-[2-(3-Methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-1-[2-(5-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


79
(RS)-1-(2-Iodo-phenyl)-1-[2-(5-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone


181
(RS)-1-{2-[5-(2,3-Difluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-methanone









and pharmaceutically acceptable salts thereof.

Additional compounds of formula (I) can be selected from:













80
1-{(S)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-pyrrolidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


81
1-{(S)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-pyrrolidin-1-yl}-1-[4-(4-



fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


82
1-{(S)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-pyrrolidin-1-yl}-1-[4-(4-



fluoro-phenyl)-1H-pyrazol-3-yl]-methanone


83
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


84
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[4-(4-



fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


85
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[4-(4-



fluoro-phenyl)-1H-pyrazol-3-yl]-methanone


86
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-(2-



methoxy-pyridin-3-yl)-methanone


87
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-



isoquinolin-3-yl-methanone


88
(RS)-1-{2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-



[1,8]naphthyridin-2-yl-methanone


89
(RS)-1-[1-(2-Dimethylamino-ethyl)-4-(4-fluoro-phenyl)-1H-pyrazol-3-yl]-1-{2-[4-(4-



fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


90
(RS)-1-[5-(4-Fluoro-phenyl)-2-hydroxymethyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-



phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


91
(RS)-1-{2-[4-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl[-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-methanone


92
(RS)-1-{2-[4-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[2-(3-



methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone


93
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-methoxyphenyl)-1H-



imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


94
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-fluorophenyl)-1H-



imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


95
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-bromophenyl)-1H-



imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


96
(RS)-2-[2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-



2-ylmethyl)-3H-imidazol-4-yl]-benzonitrile


97
(RS)-1-{2-[4-Bromo-5-(4-fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-



[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


98
(RS)-5-(4-Fluoro-phenyl)-2-(1-{1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-



methanoyl}-piperidin-2-ylmethyl)-3H-imidazole-4-carbonitrile


102
(RS)-1-(2-Ethoxy-phenyl)-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-



methanone


103
(RS)-1-[5-(4-Fluoro-phenyl)-2-hydroxymethyl-thiazol-4-yl]-1-[2-(4-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


104
(RS)-1-[5-(4-Fluoro-phenyl)-2-hydroxymethyl-thiazol-4-yl]-1-[2-(5-phenyl-1H-



imidazol-2-ylmethyl)-piperidin-1-yl]-methanone


105
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-4H-



[1,2,4]triazol-3-ylmethyl]-piperidin-1-yl}-methanone


106
(RS)-1-{2-[5-(4-Fluoro-phenyl)-4H-[1,2,4]triazol-3-ylmethyl]-piperidin-1-yl}-1-



isoquinolin-3-yl-methanone


107
(RS)-1-{2-[3-(3-Dimethylamino-propoxy)-phenyl]-thiophen-3-yl}-1-{2-[4-(4-fluoro-



phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


108
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(3-methoxy-phenyl)-1H-



imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


109
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(3-methoxy-



phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone


110
(RS)-1-{2-[5-(3-Chloro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


111
(RS)-1-{2-[5-(3-Chloro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[4-(4-



fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanone


112
(RS)-3-[2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-



2-ylmethyl)-3H-imidazol-4-yl]-benzonitrile


113
(RS)-3-[2-(1-{1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanoyl}-



piperidin-2-ylmethyl)-3H-imidazol-4-yl]-benzonitrile


114
(RS)-1-[5-(2-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-1H-imidazol-2-



ylmethyl)-piperidin-1-yl]-methanone


115
(RS)-1-[5-(3-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-1H-imidazol-2-



ylmethyl)-piperidin-1-yl]-methanone


116
(RS)-1-(2-Methyl-5-phenyl-thiazol-4-yl)-1-[2-(5-phenyl-1H-imidazol-2-ylmethyl)-



piperidin-1-yl]-methanone


117
(RS)-1-{5-[3-(3-Dimethylamino-propoxy)-phenyl]-2-methyl-thiazol-4-yl}-1-[2-(5-



phenyl-1H-imidazol-2-ylmethyl)-piperidin-1-yl]-methanone


118
(RS)-1-{5-[3-(4-Dimethylamino-butoxy)-phenyl]-2-methyl-thiazol-4-yl}-1-[2-(5-



phenyl-1H-imidazol-2-ylmethyl)-piperidin-1-yl]-methanone


119
(RS)-1-{5-[3-(2-Dimethylamino-ethoxy)-phenyl]-2-methyl-thiazol-4-yl}-1-[2-(5-



phenyl-1H-imidazol-2-ylmethyl)-piperidin-1-yl]-methanone


120
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-



tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone


121
(RS)-1-{2-[5-(4-Fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-



phenyl)-thiazol-4-yl]-methanone


122
(RS)-1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-tetrazol-2-



ylmethyl]-piperidin-1-yl}-methanone


123
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-



tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone


124
(RS)-1-[4-(4-Fluoro-phenyl)-2-methyl-2H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-



tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone


144
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-imidazol-1-



ylmethyl)-piperidin-1-yl]-methanone


145
(RS)-1-[5-(4-Fluoro-phenyl)-thiazol-4-yl]-1-[2-(4-phenyl-imidazol-1-ylmethyl)-



piperidin-1-yl]-methanone


146
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(4-phenyl-imidazol-1-



ylmethyl)-piperidin-1-yl]-methanone


147
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-



pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone


148
(RS)-1-(5-Bromo-2-methoxy-phenyl)-1-{2-[3-(4-fluoro-phenyl)-pyrazol-1-ylmethyl]-



piperidin-1-yl}-methanone


149
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-{2-[3-(4-fluoro-



phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone


150
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-oxazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-



pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone


151
(RS)-1-{2-[3-(4-Fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-1-[2-(3-methyl-



[1,2,4]oxadiazol-5-yl)-phenyl]-methanone


152
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-thiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


153
(R)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-oxazol-2-



ylmethyl)-morpholin-4-yl]-methanone and (S)-(R)-1-[5-(4-Fluoro-phenyl)-2-methyl-



thiazol-4-yl]-1-[3-(4-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-methanone


154
(RS)-1-{2-[5-(2,5-Dimethyl-2H-pyrazol-3-yl)-[1,3,4]oxadiazol-2-ylmethyl]-



piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


155
(RS)-1-[2-(4,5-Diphenyl-1H-imidazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


156
(RS)-1-{2-[4-(4-Fluoro-phenyl)-1-methyl-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-



1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


157
(RS)-1-[2-(5-Benzofuran-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(3-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


158
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-pyridin-2-yl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


159
(RS)-1-{2-[5-(3,4-Difluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-



(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


160
(RS)-1-{2-[5-(3-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-



fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone


161
(RS)-1-[5-(4-Fluorophenyl)-2-methylthiazol-4-yl]-1-{2-[5-(4-fluorophenyl)-1H-



pyrazol-3-ylmethyl]-piperidin-1-yl}-methanone


162
(RS)-1-{2-[4-(4-Fluorophenyl)-1H-imidazol-2-ylmethyl]-piperazin-1-yl}-1-[5-(4-



fluorophenyl)-2-methylthiazol-4-yl]-methanone


163
1-[5-(4-Fluorophenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(4-fluorophenyl)-oxazol-2-



ylmethyl]-piperazin-1-yl}-methanone









and pharmaceutically acceptable salts thereof.

Further compounds of formula (I) can be selected from:













99
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[4-(4-fluoro-phenyl)-



oxazol-2-ylmethyl]-piperidin-1-yl}-methanone


100
(RS)-1-{2-[4-(4-Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-[4-(4-fluoro-



phenyl)-1H-pyrazol-3-yl]-methanone


101
(RS)-1-{2-[4-(4-Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-quinolin-2-yl-



methanone


125
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(3-



thiophen-2-yl-phenyl)-methanone


126
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(3-



thiophen-3-yl-phenyl)-methanone


127
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(2-



pyrazol-1-yl-phenyl)-methanone


128
(RS)-2′-(1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-



methanoyl)-biphenyl-4-carbonitrile


129
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(4-



methoxy-biphenyl-3-yl)-methanone


130
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(2-



pyrrol-1-yl-phenyl)-methanone


131
(RS)-1-Dibenzofuran-4-yl-1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-



piperidin-1-yl}-methanone


132
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(2-



methoxy-4-methyl-phenyl)-methanone


133
(RS)-1-(2-Ethoxy-4-methyl-phenyl)-1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-



ylmethyl]-piperidin-1-yl}-methanone


134
(RS)-1-(3,5-Dichloro-2-methoxy-phenyl)-1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-



2-ylmethyl]-piperidin-1-yl}-methanone


135
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(1-



methoxy-naphthalen-2-yl)-methanone


136
(RS)-4-Ethoxy-2-ethyl-5-(1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-



piperidin-1-yl}-methanoyl)-benzonitrile


137
(RS)-4-Ethoxy-5-(1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-



yl}-methanoyl)-2-methyl-benzonitrile


138
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-(4′-



methoxy-4-nitro-biphenyl-2-yl)-methanone


139
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(2′-



methyl-4-nitro-biphenyl-2-yl)-methanone


140
(RS)-1-{2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-(4-



nitro-biphenyl-2-yl)-methanone


141
(RS)-1-Benzofuran-7-yl-1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-



piperidin-1-yl}-methanone


142
(RS)-1-(5-Bromo-4-ethyl-2-methoxy-phenyl)-1-{2-[5-(3-fluoro-phenyl)-



[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone


143
(RS)-1-[1-Ethyl-4-(4-fluoro-phenyl)-1H-pyrazol-3-yl]-1-[2-(5-phenyl-



[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone


164
(RS)-1-[3-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


165
(RS)-1-[2-(5-Chloro-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


166
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-4H-[1,2,4]triazol-3-



ylmethyl)-pyrrolidin-1-yl]-methanone


167
(RS)-1-[2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


168
(RS)-1-(2-Methyl-5-phenyl-thiazol-4-yl)-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-



1-yl]-methanone


169
(RS)-1-[1-(2-Dimethylamino-ethyl)-4-(4-fluoro-phenyl)-1H-pyrazol-3-yl]-1-[2-(4-



phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone


170
(RS)-2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-



ylmethyl)-4-phenyl-oxazole-5-carbonitrile


171
(RS)-1-[2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-1-(2-methyl-5-



phenyl-thiazol-4-yl)-methanone


172
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(4-phenyl-oxazol-2-ylmethyl)-



pyrrolidin-1-yl]-methanone


173
1-[(S)-2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-pyrrolidin-1-yl]-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


174
(RS)-1-[5-(4-Chloro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-oxazol-2-



ylmethyl)-piperidin-1-yl]-methanone


175
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(4-phenyl-thiazol-2-



ylmethyl)-piperidin-1-yl]-methanone


176
(RS)-1-{2-[4-(2-Bromo-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-



phenyl)-2-methyl-thiazol-4-yl]-methanone


177
(RS)-2-[2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-



ylmethyl)-oxazol-4-yl]-benzonitrile


178
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(2-fluoro-phenyl)-thiazol-



2-ylmethyl]-piperidin-1-yl}-methanone


179
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(3-fluoro-phenyl)-thiazol-



2-ylmethyl]-piperidin-1-yl}-methanone


180
(RS)-1-{2-[4-(3-Fluoro-phenyl)-thiazol-2-ylmethyl]-piperidin-1-yl}-1-(2-methyl-5-



phenyl-thiazol-4-yl)-methanone









and pharmaceutically acceptable salts thereof.

When a halogen atom is present in the compound of formula (I) it may be fluorine, chlorine, bromine or iodine, preferably fluorine.
When the compound of formula (I) contains an alkyl group, whether alone or forming part of a larger group, e.g. alkoxy or alkylthio, the alkyl group may be straight chain, branched or cyclic, or combinations thereof, it is preferably methyl or ethyl.
When used herein the term aryl means a 5- to 6-membered aromatic ring, for example phenyl, or a 7 to 12 membered bicyclic ring system where at least one of the rings is aromatic, for example naphthyl.
It will be appreciated that compounds of formula (I) may exist as R or S enantiomers. The present invention includes within its scope all such isomers, including mixtures. Where additional chiral centres are present in compounds of formula (I), the present invention includes within its scope all possible diastereoismers, including mixtures thereof. The different isomeric forms may be separated or resolved one from the other by conventional methods, or any given isomer may be obtained by conventional synthetic methods or by stereospecific or asymmetric syntheses.
It will be understood that the invention includes pharmaceutically acceptable derivatives of compounds of formula (I) and that these are included within the scope of the invention.
Particular compounds according to the invention include those mentioned in the examples and their pharmaceutically acceptable derivatives.
As used herein “pharmaceutically acceptable derivative” includes any pharmaceutically acceptable salt, ester or salt of such ester of a compound of formula (I) which, upon administration to the recipient is capable of providing (directly or indirectly) a compound of formula (I) or an active metabolite or residue thereof.
It will be appreciated that for use in medicine the salts of the compounds of formula (I) should be pharmaceutically acceptable. Suitable pharmaceutically acceptable salts will be apparent to those skilled in the art and include acid addition salts formed with inorganic acids e.g. hydrochloric, hydrobromic, sulphuric, nitric or phosphoric acid; and organic acids e.g. succinic, maleic, acetic, fumaric, citric, tartaric, benzoic, p-toluenesulfonic, methanesulfonic or naphthalenesulfonic acid. Other salts e.g. oxalates, may be used, for example in the isolation of compounds of formula (I) and are included within the scope of this invention. Also included within the scope of the invention are solvates and hydrates of compounds of formula (I).
Certain of the compounds of formula (I) may form acid addition salts with one or more equivalents of the acid. The present invention includes within its scope all possible stoichiometric and non-stoichiometric forms.
Since the compounds of formula (I) are intended for use in pharmaceutical compositions it will readily be understood that they are each preferably provided in substantially pure form, for example at least 60% pure, more suitably at least 75% pure and preferably at least 85%, especially at least 98% pure (% are on a weight for weight basis). Impure preparations of the compounds may be used for preparing the more pure forms used in the pharmaceutical compositions.
According to a further feature of the invention there is provided a process for the preparation of compounds of formula (I) and salts thereof. The following schemes detail some synthetic routes to compounds of the invention




wherein X, Het and Ar2 are as defined for compounds of formula (I), P is a protecting group and M is a metal, for example, lithium.
Examples of suitable leaving groups L1 include halogen, OC(═O)alkyl and OC(═O)O-alkyl. The transformation (II) to (I) may be carried out in an inert solvent such as dichloromethane, in the presence of a base such as triethylamine. Alternatively this step may be carried out when L1 represents hydroxy, in which case reaction with (II) takes place in an inert solvent such as dichloromethane in the presence of a diimide coupling reagent such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, and an activator such as 1-hydroxybenzotriazole.
Examples of protecting groups P include t-butyloxycarbonyl, trifluoroacetyl and benzyloxycarbonyl. Deprotection conditions are respectively, acid (e.g. trifluoroacetic acid in dichloromethane), base (e.g. sodium hydroxide in a solvent such as aqueous methanol) and catalytic hydrogenolysis in an inert solvent (e.g using palladium on charcoal in a lower alcohol or ethyl acetate).
Compounds of formula (V) are known in the literature or can be prepared by known methods.
Compounds of formula (I) when Het is a 5-aryl-1,3,4-oxadiazole can be prepared by the process described in scheme 2a, or 2b, where X, Ar2 and R2 are as defined for compounds of formula (I).








Compounds of formula (I) when Het is substituted 3-(1,2,4-oxadiazole) can be prepared by the process described in scheme 3 where X, Ar2 and R2 are as defined for compounds of formula (I).




Compounds of formula (I) when Het is a 2-(4-aryloxazole) can be prepared by the process described in Scheme 4 where X, Ar2 and R2 are as defined for compounds of formula (I).




Compounds of formula (I) when Het is a 2-5-aryloxazole) can be prepared by the process described in Scheme 5 where X, Ar2 and R2 are as defined for compounds of formula (I).




Compounds of formula (I) where Het is a 2-(4-substituted imidazole) can be prepared by the process described in scheme 6 where X, Ar2 and R2 are as defined for compounds of formula (I).




wherein Ar2 X, R2 are as defined for compounds of formula (I).

Scheme 7
Compounds of formula (I) wherein the Het group is linked to the cyclic ring through a nitrogen in the Het group, can be prepared by the process defined in scheme 7 wherein X, Ar2 and R2 are as defined for compounds of formula (I).




Compounds wherein the Het group is substituted can be prepared by the process defined in scheme 8 wherein Ar2, X and R2 are as defined for compounds of formula (I).




Compounds of formula (I) where Het is a 2-(4-arylthiazole) can be prepared by the process described in Scheme 9 where X, Ar2 and R2 are as defined for compounds of formula (I).




Compounds of formula (I) where Het is a 3-(5-aryltriazole) can be prepared by the process described in Scheme 10 where X, Ar2 and R2 are as defined for compounds of formula (I).




All starting materials used in the above schemes are commercially available or prepared by known literature methods.
The compounds of formula (I) may be prepared singly or as compound libraries comprising at least 2, e.g. 5 to 1000, preferably 10 to 100 compounds of formula (I). Compound libraries may be prepared by a combinatorial ‘split and mix’ approach or by multiple parallel synthesis using either solution phase or solid phase chemistry, by procedures known to those skilled in the art.
Thus according to a further aspect of the invention there is provided a compound library comprising at least 2 compounds of formula (I), or pharmaceutically acceptable derivatives thereof.
Pharmaceutically acceptable salts may be prepared conventionally by reaction with the appropriate acid or acid derivative.
The compounds of formula (I) and their pharmaceutically acceptable derivatives are useful for the treatment of diseases or disorders where an antagonist of a human orexin receptor is required such as obesity and diabetes; prolactinoma; hypoprolactinemia; hypothalamic disorders of growth hormone deficiency; idiopathic growth hormone deficiency; Cushings syndrome/disease; hypothalamic-adrenal dysfunction; dwarfism; sleep disorders; sleep apnea; narcolepsy; insomnia; parasomnia; jet-lag syndrome; sleep disturbances associated with diseases such as neurological disorders, neuropathic pain and restless leg syndrome; heart and lung diseases; depression; anxiety; addictions; obsessive compulsive disorder; affective neurosis/disorder; depressive neurosis/disorder; anxiety neurosis; dysthymic disorder; behaviour disorder; mood disorder; sexual dysfunction; psychosexual dysfunction; sex disorder; sexual disorder; schizophrenia; manic depression; delerium; dementia; bulimia and hypopituitarism. The compounds of formula (I) or pharmaceutically acceptable derivatives thereof are also useful in the treatment of stroke, particularly ischemic and haemorrhagic. Furthermore the compounds of formula (I) or pharmaceutically acceptable derivatives thereof are useful in blocking the emetic response i.e. nausea and vomiting.
The compounds of formula (I) and their pharmaceutically acceptable derivatives are particularly useful for the treatment of obesity, including obesity associated with Type 2 diabetes, and sleep disorders, Additionally the compounds are useful in the the treatment of stroke and blocking the emetic response, i.e. nausea and vomiting.
Other diseases or disorders which may be treated in accordance with the invention include disturbed biological and circadian rhythms; adrenohypophysis disease; hypophysis disease; hypophysis tumor/adenoma; adrenohypophysis hypofunction; functional or psychogenic amenorrhea; adrenohypophysis hyperfunction; migraine; hyperalgesia; pain; enhanced or exaggerated sensitivity to pain such as hyperalgesia, causalgia and allodynia; acute pain; burn pain; a typical facial pain; neuropathic pain; back pain; complex regional pain syndromes I and II; arthritic pain; sports injury pain; pain related to infection e.g. HIV, post-polio syndrome and post-herpetic neuralgia; phantom limb pain; labour pain; cancer pain; post-chemotherapy pain; post-stroke pain; post-operative pain; neuralgia; and tolerance to narcotics or withdrawal from narcotics.
The invention also provides a method of treating or preventing diseases or disorders where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable derivative thereof.
The invention also provides a compound of formula (I), or a pharmaceutically acceptable derivative thereof, for use in the treatment or prophylaxis of diseases or disorders where an antagonist of a human orexin receptor is required.
The invention also provides the use of a compound of formula (I), or a pharmaceutically acceptable derivative thereof, in the manufacture of a medicament for the treatment or prophylaxis of diseases or disorders where an antagonist of a human orexin receptor is required.
For use in therapy the compounds of the invention are usually administered as a pharmaceutical composition. The invention also provides a pharmaceutical composition comprising a compound of formula (I), or a pharmaceutically acceptable derivative thereof, and a pharmaceutically acceptable carrier.
The compounds of formula (I) and their pharmaceutically acceptable derivatives may be administered by any convenient method, e.g. by oral, parenteral, buccal, sublingual, nasal, rectal or transdermal administration, and the pharmaceutical compositions adapted accordingly.
The compounds of formula (I) and their pharmaceutically acceptable derivatives which are active when given orally can be formulated as liquids or solids, e.g. as syrups, suspensions, emulsions, tablets, capsules or lozenges.
A liquid formulation will generally consist of a suspension or solution of the active ingredient in a suitable liquid carrier(s) e.g. an aqueous solvent such as water, ethanol or glycerine, or a non-aqueous solvent, such as polyethylene glycol or an oil. The formulation may also contain a suspending agent, preservative, flavouring and/or colouring agent.
A composition in the form of a tablet can be prepared using any suitable pharmaceutical carrier(s) routinely used for preparing solid formulations, such as magnesium stearate, starch, lactose, sucrose and cellulose.
A composition in the form of a capsule can be prepared using routine encapsulation procedures, e.g. pellets containing the active ingredient can be prepared using standard carriers and then filled into a hard gelatin capsule; alternatively a dispersion or suspension can be prepared using any suitable pharmaceutical carrier(s), e.g. aqueous gums, celluloses, silicates or oils and the dispersion or suspension then filled into a soft gelatin capsule.
Typical parenteral compositions consist of a solution or suspension of the active ingredient in a sterile aqueous carrier or parenterally acceptable oil, e.g. polyethylene glycol, polyvinyl pyrrolidone, lecithin, arachis oil or sesame oil. Alternatively, the solution can be lyophilised and then reconstituted with a suitable solvent just prior to administration.
Compositions for nasal administration may conveniently be formulated as aerosols, drops, gels and powders. Aerosol formulations typically comprise a solution or fine suspension of the active ingredient in a pharmaceutically acceptable aqueous or non-aqueous solvent and are usually presented in single or multidose quantities in sterile form in a sealed container which can take the form of a cartridge or refill for use with an atomising device. Alternatively the sealed container may be a disposable dispensing device such as a single dose nasal inhaler or an aerosol dispenser fitted with a metering valve. Where the dosage form comprises an aerosol dispenser, it will contain a propellant which can be a compressed gas e.g. air, or an organic propellant such as a fluorochlorohydrocarbon or hydrofluorocarbon. Aerosol dosage forms can also take the form of pump-atomisers.
Compositions suitable for buccal or sublingual administration include tablets, lozenges and pastilles where the active ingredient is formulated with a carrier such as sugar and acacia, tragacanth, or gelatin and glycerin.
Compositions for rectal administration are conveniently in the form of suppositories containing a conventional suppository base such as cocoa butter.
Compositions suitable for transdermal administration include ointments, gels and patches.
Preferably the composition is in unit dose form such as a tablet, capsule or ampoule.
The dose of the compound of formula (I), or a pharmaceutically acceptable derivative thereof, used in the treatment or prophylaxis of the abovementioned disorders or diseases will vary in the usual way with the particular disorder or disease being treated, the weight of the subject and other similar factors. However, as a general rule, suitable unit doses may be 0.05 to 1000 mg, more suitably 0.05 to 500 mg. Unit doses may be administered more than once a day for example two or three times a day, so that the total daily dosage is in the range of about 0.01 to 100 mg/kg; and such therapy may extend for a number of weeks or months. In the case of pharmaceutically acceptable derivatives the above figures are calculated as the parent compound of formula (I).
No toxicological effects are indicated/expected when a compound of formula (I) is administered in the above mentioned dosage range.
Human orexin-A has the amino acid sequence:








pyroGlu Pro Leu Pro Asp Cys Cys Arg Gln Lys Thr Cys Ser Cys Arg Leu



 1              5                 10                  15


 


Tyr Glu Leu Leu His Gly Ala Gly Asn His Ala Ala Gly Ile Leu Thr


            20                 25                 30


 


Leu-NH2






Orexin-A can be employed in screening procedures for compounds which inhibit the ligand's activation of the orexin-1 receptor.
In general, such screening procedures involve providing appropriate cells which express the orexin-1 receptor on their surface. Such cells include cells from mammals, yeast, Drosophila or E. coli. In particular, a polynucleotide encoding the orexin-1 receptor is used to transfect cells to express the receptor. The expressed receptor is then contacted with a test compound and an orexin-1 receptor ligand to observe inhibition of a functional response. One such screening procedure involves the use of melanophores which are transfected to express the orexin-1 receptor, as described in WO 92/01810.
Another screening procedure involves introducing RNA encoding the orexin-1 receptor into Xenopus oocytes to transiently express the receptor. The receptor oocytes are then contacted with a receptor ligand and a test compound, followed by detection of inhibition of a signal in the case of screening for compounds which are thought to inhibit activation of the receptor by the ligand.
Another method involves screening for compounds which inhibit activation of the receptor by determining inhibition of binding of a labelled orexin-1 receptor ligand to cells which have the receptor on their surface. This method involves transfecting a eukaryotic cell with DNA encoding the orexin-1 receptor such that the cell expresses the receptor on its surface and contacting the cell or cell membrane preparation with a compound in the presence of a labelled form of an orexin-1 receptor ligand. The ligand may contain a radioactive label. The amount of labelled ligand bound to the receptors is measured, e.g. by measuring radioactivity.
Yet another screening technique involves the use of FLIPR equipment for high throughput screening of test compounds that inhibit mobilisation of intracellular calcium ions, or other ions, by affecting the interaction of an orexin-1 receptor ligand with the orexin-1 receptor.
All publications, including but not limited to patents and patent applications, cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein as though fully set forth.
The following Examples illustrate the preparation of pharmacologically active compounds of the invention. The Descriptions D1-D57 illustrate the preparation of intermediates to compounds of the invention.
In the Examples 1H NMR's were measured at 250 MHz in CDCl3 unless otherwise stated.
The following abbreviations are used herein;


    PyBop means benzotriazol-1-yloxytris(pyrrolidino)phosphonium hexafluorophosphate
    THF means tetrahyrdofuran
    EDC.HCL means 1-(3-dimethylaminopropryl)3-ethylcarbodiimide hydrochloride.
    DMF means N,N-dimethylformamide
    HATU means O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophospliate


The following Examples illustrate the preparation of pharmacologically active compounds of the invention. The Descriptions D1-D123 illustrate the preparation of intermediates to compounds of the invention.
Description 1 (RS)-2-(5-Phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine-1-carboxylic acid tert butyl ester
A mixture of 2carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.22 g), (Peschke, Bernd; Ankersen, Michael; Hansen, Birgit Sehested; Hansen, Thomas Kruse; Johansen, Nils Langeland; Lau, Jesper; Madsen, Kjeld; Petersen, Hans; Thogersen, Henning; Watson, Brett. Eur. J. Med. Chem. (1999), 34(5), 363-380), dicyclohexylcarbodiimide (1.05 g) and 5-phenyltetrazole (0.73 g) in toluene (25 ml) was heated at 100° C. for 3 h. The reaction mixture was cooled to room temperature, diluted with diethyl ether and solvent decanted from the precipitated gum. The gum was column chromatographed (silica gel, 0-50% ethyl acetate in pentane eluant) to give the title compound (1.1 g).
Mass Spectrum (API+): Found 344 (MH+). C19H25N3O3 requires 343.
1H NMR δ: (CDCl3) 1.31 (9H, s), 1.43-1.69(6H,m), 2.95 (1H, t), 3.09 (1H, dd), 3.30(1H, dd), 4.11 (1H, br. s), 4.79 (1H, br. s.), 7.51 (3H, m) and 8.05 (2H, m).
Description 2 (RS)-2-(5-Phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine
A solution of (RS)-2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine-1-carboxylic acid tert butyl ester (0.175 g) in dichloromethane (4 ml) was cooled (ice bath) and treated with trifluoroacetic acid (1 ml). The mixture was stirred for 1 h, added to saturated potassium carbonate and the product extracted into dichloromethane. The organic phase was dried (MgSO4) and solvent removed at reduced pressure to give the title compound (0.115 g)
Mass Spectrum (API+): Found 244 (MH+). C14H16F3N3O requires 243.
1H NMR δ: (CDCl3) 1.18-1.85 (6H, m), 2.68 (1H, m), 2.97 (2H, m), 3.10(2H, m), 7.55 (3H, m) and 8.05 (2H, m).
Description 3 (RS)-2-[5-(3-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound ((1.28 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.48 g), 5-(3-fluorophenyl)tetrazole (1.0 g) and dicyclohexylcarbodiimide (1.25 g) according to the method of description 1.
Mass Spectrum (API+): Found 362 (MH+). C19H24FN3O3 requires 361.
Description 4 (RS)-2-[5-(3-Fluoro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.81 g) was prepared from the compound of description 3 (1.27 g) according to the method of description 2.
Mass Spectrum (API+): Found 262 (MH+). C14H16FN3O3 requires 261.
1H NMR δ: (CDCl3) 1.38-1.84 (6H, m), 2.71 (1H, m), 3.02 (2H, m), 3.14(2H, m), 7.22 (1H, dd), 7.48 (1H, m), 7.73 (1H, dd) and 7.83 (1H, dd).
Description 5 (RS)-2-[5-(3-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.21 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.35 g), 5-(3-chlorophenyl)tetrazole (1.0 g) and dicyclohexylcarbodiimide (1.15 g) according to the method of description 1.
Mass Spectrum (API+): Found 378 (MH+). C19H24ClN3O3 requires 377.
Description 6 (RS)-2-[5-(3-Chloro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.89 g) was prepared from the compound of description 5 (1.21 g) according to the method of description 2.
Mass Spectrum (API+): Found 278 (MH+). C14H16ClN3O requires 277.
1H NMR δ: (CDCl3) 1.43-1.90 (6H, m), 2.79 (1H, m), 3.05-3.18 (2H, m), 3.27 (2H, m), 7.40-7.52 (2H, m), 7.91 (1H, dd) and 8.00 (1H, d).
Description 7 (RS)2-(5-Pyridin-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.39 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.65 g), 5-(pyridin-2-yl)tetrazole (1.0 g) and dicyclohexylcarbodiimide (1.43 g) according to the method of description 1.
Mass Spectrum (API+): Found 345 (MH+). C18H24N4O3 requires 344.
Description 8 (RS)-2-(5-Piperidin-2-ylmethyl-[1,3,4]oxadiazol-2-yl)-pynidine
The title compound (0.89 g) was prepared from the compound of description 7 (1.39 g) according to the method of description 2.
Mass Spectrum (API+): Found 245 (MH+). C13H16N4O requires 244.
1H NMR δ: (CDCl3) 1.49-1.90 (6H, m), 2.72-2.82 (2H, m), 3.07-3.29 (4H, m), 7.44-7.49 (1H, m), 7.85-7.92 (1H, m), 8.22 (1H, dd) and 8.76 (1H, dd).
Description 9 (RS)-2-[5-(4-Fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.34 g) was prepared from 2-carboxymethyl-piperidine-1-carboxzylic acid tert butyl ester (1.22 g), 5-(4-fluorophenyl)tetrazole (0.82 g) and dicyclohexylcarbodiimide (1.05 g) according to the method of description 1.
Mass Spectrum (API+): Found 362 (MH+). C19H24FN3O3 requires 361.
Description 10 (RS)-2-[5-(4-Fluoro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (7.32 g) was prepared from the compound of description 9 (1.2 g) according to the method of description 2.
Mass spectrum (API+): Found 262 (MH+). C14H16FN3O3 requires 261.
1H NMR δ: (CDCl3) 1.25-1.84 (6H, m), 2.68 (1H, m), 21.86 (2H, m), 3.07 (2H, m), 7.12-7.27 (3H, m) and 8.04 (2H,m).
Description 11 (RS)-2-[5-(4-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.65 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.26 g), 5-(4-chlorophenyl)tetrazole (1.08 g) and dicyclohexylcarbodiimide (1.15 g) according to the method of description 1.
Mass Spectrum (API+); Found 378, 380 (MH+). C19H24ClN3O3 requires 377, 379.
Description 12 (RS)-2-[5-(4-Chloro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.89 g) was prepared from the compound of description (11 (1.21 g) according to the method of description 2.
Mass spectrum (API+): found 278, 280 (MH+). C14H16ClN3O requires 277, 279.
1H NMR δ: (CDCl3) 1.43-1.90 (6H, m), 2.79 (1H, m), 3.05–3.18 (2H, m ), 3.27 (2H, m), 7.40-7.52 (2H, m), 7.91 (1H, dd) and 8.00 91H, d).
Description 13 (RS)-2-[5-(2-Chloro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.65 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.35 g), 5-(2-chlorophenyl)tetrazole (1.0 g) and dicyclohexylcarbodiimide (1.16 g) according to the method of description 1.
Mass Spectrum (API+): Found 378, 380 (MH+). C19H24ClN3O3 requires 377, 379.
Description 14 (RS)-2-[5-(2-Chloro-phenyl-[1,3,4]oxadiazol-02-ylmethyl]-piperidine
The title compound (1.10 g) was prepared from the compuond of description 13 (1.48 g) according to the method of description 2.
Mass Spectrum (API+): Found 278, 280 (MH+). C14H16ClN3O requires 277, 279.
1H NMR δ: (CDCl3) 1.11-1.85 (6H, m), 2.69 (1H, m), 3.00 (2H, m), 3.10 (2H, m), 7.38 (1H, t), 7.46 (1H, t), 7.54 (1H, dd) and 7.97 (1H, dd).
Description 15 (RS)-2-[5-0(2,3-dichloro-phenyl)-1,3,4]oxadiazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.70 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.13 g), 5-(2,3-dichlorophenyl)tetrazole (1.0 g) and dicyclohexylcarbodiimide (0.98 g) according to the method of description 1.
Mass Spectrum (API+): Found 412, 414 (MH+). C19H23Cl2N3O3 requires 411, 413.
Description 16 (RS-2-[5-(2,3-Dichloro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.47 g) was prepared from the compound of description 15 (0.62 g) according to the method of description 2.
Mass Spectrum (API+): Found 312, 314 (MH+). C14H15Cl2N3O requires 311, 313.
1H NMR δ: (CDCl3) 1.26-1.82 (6H, m), 2.69 (1H, m), 3.01 (2H, m), 3.10 (2H, m), 7.33 (1H, t), 7.66 (1H, dd) and 7.86 (1H, dd).
Description 17 (RS)-2-Hydrazinocarbonylmethyl-piperidine-1-carboxylic acid tert butyl ester
2-Methoxycarbonylmethyl-piperidine-1-carboxylic acid tert butyl ester (8.14 g) in ethanol (150 ml) was treated with hydrazine hydrate (19 ml) and the mixture boiled for 16 h. Solvent was removed at reduced pressure and the residue azeotroped with toluene to give the title compound (8.34 g)
1HNMR δ: (CDCl3) 1.47 (9H, s), 1.62 (6H, m), 2.34-2.42 (2H, m), 2.59-2.85 (3H, m), 3.85 (1H, br. s.), 3.97 (1H, br. s.) and 4.62 (1H, br. s).
Description 18 (RS)-2-(2-{N′-[-1-(2-Fluoro-phenyl)-methanoyl]-hydrazino}-2-oxo-ethyl) -piperidine-1-carboxylic acid tert butyl ester
To a solution of the compound of description 17 (1.0 g) in pyridine (10 ml), 2-fluorobenzoyl chloride (0.62 g) was added. The mixture was stirred for 2 h, diluted with water and the milky solution extracted with ethyl acetate (×2). The combined organic phase was washed with brine, dried (MgSO4) and solvent removed at reduced pressure. The residue was triturated with pentane to give after drying under reduced pressure at 35° C., the title compound (1.4 g).
Mass Spectrum (API+): Found 380 (MH+). C19H26FN3O4 requires 379.
Description 19(RS)-2-[5-(2-Fluoro-phenyl-[9,3,4]oxadiazol-2-ylmethyl]-piperidine
The benzoyl hydrazide of description 18 (0.2 g) was added to polyphosphoric acid (2 g) at 45° C., the reaction temperature was increased to 150° C. and heating continued for 2 b. The reaction mixture was poured onto potassium carbonate in crushed iced and the mixture extracted with dichloromethane (×3). The combined organic extracts were washed with brine, dried (MgSO4) and solvent removed it reduced pressure to give the title compound (0.08 g) as a yellow oil.
Mass Spectrum (API+): Found 262 (MH+). C14H16FN3O3 requires 261.
Description 20 (RS)-(2-{N′-(1-Benzofuran-4-yl-methanoyl)-hydrazino]-2-oxo-ethyl}-piperidine-1-carboxylic acid tert butyl ester
A mixture of benzofuran-4-carboxylic acid (0.90 g), diisopropylethylamine (3.2 ml) and [O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate] (2.09 g) in dimethylformamide (20 ml) was stirred for 15 min and then treated with the benzoyl hydrazide of description 17 (1.43 g). The mixture was stirred for 16 h, diluted with water and extracted with diethyl ether. The ether extract was washed with water (×3), dried (MgSO4) and solvent removed at reduced pressure. The residue was suspended in a mixture of diethyl ether/dichloromethane (30 ml, 2:1) to give the title compound (1.29 g) as a colourless solid.
Mass Spectrum (API+): Found 402 (MH+). C21H27N3O5 requires 401
Description 21 (RS)-2-(5-Benzofuran-4-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine
The title compound (0.1 g) was prepared from the compound of description 20 (0.2 g) according to the method of description 19. The obtained compound was used without further purification.
Mass Spectrum (API+): Found 284 (MH+). C16H17N3O2 requires 283
Description 22 (RS)-2-(2-{N′-[1-(2,3-Difluoro-phenyl)-methanoyl]-hydrazino}-2-oxo-ethyl)-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.15 g) was prepared from the compound of description 17 (1.0 g) and 2,3-difluorobenzoyl chloride (0.49 ml) according to the method of description 18.
Mass Spectrum (API+): Found 398 (MH+). C19H25F2N3O4 requires 397
Description 23 (RS)-2-[5-(2,3-Difluoro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.70 g) was prepared from the compound of description 22 (1.1 g) according to the method of description 19. The compound was used without further purification.
Mass Spectrum (API+): Found 280 (MH+). C14H15F2N30 requires 279.
Description 24 (RS)-2-(2-{N′-[1-(2,5-Difluoro-phenyl)-methanoyl]-hydrazino}-2-oxo-ethyl)-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.50 g) was prepared from the compound of description 17 (1.0 g) and 2,5-difluorobenzoyl chloride (0.49 ml) according to the method of description 18.
Mass Spectrum (API+): Found 398 (MH+). C19H25F2N3O4 requires 39
Description 25 (RS)-2-[5-(2,5-Difluoro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.83 g) was prepared from the compound of description 24 (1.5 g) according to the method of description 19.
Mass Spectrum (API+); Found 280 (MH+). C14H15F2N3O requires 279.
1H NMR δ: (CDCl3) 1.28-1.82 (6H, m), 2.63-2.74 (1H, m), 2.97-3.11 (4H, m), 7.20-7.31 (3H, m).
Description 26 (RS)-2-(2-{N′-[1-(3,5-Difluoro-phenyl)-methanoyl]-hydrazino}-2-oxo-ethyl)-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.79 g) was prepared from the compound of description 17 (1.0 g) and 3,5-difluorobenzoic acid (0.62) according to the method of description 20.
Mass Spectrum (API+): Found 398 (MH+). C19H25F2N3O4 requires 397
1H NMR δ: (CDCl3) 1.45 (9H, s), 1.66 (6H, s), 2.52-2.87 (311, m), 3.98 (1H, d), 4.72 (1H, m), 6.96 (1H, m) and 7.34 (2H, m).
Description 27 (RS)-2-[5-(3,5-Difluoro-phenyl-[1,3,4]oxadiazol-2-ylmethyl]-piperidine
The title compound (0.44 g) was prepared from the compound of description 26 (0.79 g) according to the method of description 19. The compound was used without further purification.
Mass Spectrum (API+): Found 280 (MH+). C14H15F2N3O requires 279.
Description 28 (RS)-2-(2-{N′-[1-(6Methyl-pyridin-2-yl)-methanoyl]-hydrazino}-2-oxo-ethyl)-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.18 g) was prepared from the compound of description 17 (1.50 g) and 6-methylpicolinic acid (0.79 g) according to the method of description 20.
Mass Spectrum (API+): Found 377 (MH+). C19H28N4O4 requires 376
Description 29 (RS)-2-Methyl-6-(5-piperidin-2-ylmethyl-[1,3,4]oxadiazol-2-yl)-pyridine
The title compound (0.60 g) was prepared from the compound of description 28 (1.17 g) according to the method of description 19. The compound was used without further purification.
Mass Spectrum (API+): Found 259 (MH+). C14H18N4O requires 258.
Description 30 (RS)-2-{2-[N′-(1-Furan-2-yl-methanoyl)-hydrazino]-2-oxo-ethyl}-piperidine-1-carboxylic acid tert butyl ester
2-Carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.0 g) was added to [O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate] (3.13 g) in dimethylformamide (10 ml) containing diisopropylethylamine (3.2 g) and the mixture stirred for 15 min. 2-Furoic acid hydrazide (1.04 g) was then added and stirring continued for 16 h. The reaction mixture was diluted with water and extracted with diethyl ether. The combined ether extracts were washed with water, dried and solvent removed at reduced pressure the residue was column chromatographed (silica gel, 20-50% ethyl acetate/hexane) to give the title compound (2.05 g).
Mass Spectrum (API+): Found 352 (MH+). C17H25N3O5 requires 351.
Description 31 (RS)-2-(5-Furan-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine
The title compound (0.40 g) was prepared from the compound of description 30 (1.0 g) according to the method of description 19. The compound was used without further purification.
Mass Spectrum (API+): Found 234 (MH+). C12H15N3O2 requires 233.
1HNMR δ: (CDCl3) 1.09-1.71 (6H, m), 2.42-2.56 (3H, m), 2.89 (2H, m), 6.79 (1H, m), 7.30 (1H, m) and 8.03 (1H, m)
Description 32 (S)-2-(5-Phehyl-[1,3,4]oxadiazol-2-ylmethyl)-pyrrolidine-1-carboxylic acid tert butyl ester
The title compound was prepared from (S)-2-carboxymethyl-pyrrolidine-1-carboxylic acid tert butyl ester (2.50) and 5-phenyltetrazole (1.59 g) according to the method of description 1.
Mass Spectrum (API+): Found 330 (MH+). C18H23N3O3 requires 329.
1H NMR δ: (CDCl3) 1.49 (9H, s), 1.81-1.88 (2H, m), 2.17-2.25 (2H, m), 2.40 and 3.09 (1H, m), 3.35-3.73 (3H, m), 4.28, 5.12 (1H, m), 7.50 (3H, m) and 8.03 (2H, m).
Description 33 2-Phenyl-5-(S)-1-pyrrolidin-2-ylmethyl-[1,3,4]oxadiazole
The title compound (1.85 g) was prepared from the compound of description 32 (2.45 g) according to the method of description 2.
Mass Spectrum (API+): Found 230 (MH+). C13H15N3O requires 229.
1HNMR δ: (CDCl3) 1.58-1.69 (2H, m), 1.76-1.97 (2H, m), 2.04-2.36 (1H, m), 2.99-3.23 (4H, m), 3.69-3.80 (1H, m), 7.45-7.57 (3H, m) and 8.01-8.05 (2H, m).
Description 34 (1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4yl]-methanoyl}-piperidin-2-yl)-acetic acid methyl ester
The title compound (2.1 g) was prepared from piperidin-2-yl-acetic acid methyl ester (3.4 g) and 2methyl-5-(4-fluorophenyl)-thiazole-4-carboxylic acid (2.20 g) according to the method of description 20.
Mass Spectrum (API+): Found 377 (MH+). C19H21FN2O3S requires 376.
Description 35 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid
The compound of description 34 (3.4 g) in methanol (75 ml) was treated with water (25 ml) containing sodium hydroxide (0.74 g). The mixture was stirred for 16 h, solvent removed at reduced pressure, the residue dissolved in water and washed with diethyl ether. The aqueous phase was acidified with 5N hydrochloric acid and extracted with ethyl acetate. The organic phase was dried (MgSO4) and solvent removed at reduced pressure. The residue was triturated with pentane and dried in vacuo to give the title compound (20.95 g)
Mass Spectrum (API+): Found 363 (MH+). C18H19FN2O3S requires 362
Description 36 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(4-fluoro-phenyl)-2-oxo-ethyl ester
The acid of description 35 (0.4 g) was dissolved in dimethylformamide (10 ml) containing potassium carbonate (0.179 g) and 2-bromo-4′-fluoroacetophenone (0.24 g) and the mixture stirred for 16 h. Water (20 ml) was added and the mixture extracted with ethyl acetate. The organic phase was washed with water, dried (MgSO4) and solvent removed at reduced pressure to give the title compound (0.51 g).
Mass Spectrum (API+): Found 499 (MH+). C26H24F2N2O4S requires 498
1HNMR δ: (CDCl3) (doubling of signals due to restricted rotation) 1.41-1.88 (6H, m), 2.49-2.92, 3.37 (411, m), 2.68, 2.69 (3H, s), 4.15, 4.67 (1H, m), 5.13-5.31 (2H, m), 7.05 (2H, m). 7.17 (2H, m), 7.44-7.54 (2H, m) and 7.88-7.98 (2H, m).
Description 37 (RS)-(1-{1-[5-(4-Fluoro-pheuyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(2-methoxyphenyl)-2-oxo-ethyl ester
The title compound (0.51 g) was prepared from the acid of description 35 (0.40 g) and 2-bromo-4′-methoxyacetophenone (0.25 g) according to the method of description 36.
Mass Spectrum (API+): Found 511 (MH+). C27H27FN2O5S requires 510.
Description 38 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(3-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.32 g) was prepared from the acid of description 35 (0.40 g) and 2-bromo-3′-fluoroacetophenone (0.24 g) according to the method of description 36.
Mass Spectrum (API+): Found 499 (MH+). C26H24F2N2O4S requires 498
Description 39 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(2-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.32 g) was prepared from the acid of description 35 (0.40 g) and 2-bromo-2′-fluoroacetophenone (0.24 g) according to the method of description 36.
Mass Spectrum (API+): Found 499 (MH+). C26H24F2N2O4S requires 498
Description 40 (1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 1-methyl-2-oxo-2-phenyl-ethyl ester
The title compound (0.452 g) was prepared from the acid of description 35 (0.40 g) and 2-bromopropiophenone (0.234 g) according to the method of description 36.
Mass Spectrum (API+): Found 495 (MH+). C27H27FN2O4S requires 494
Description 41: (RS)-1tert-butyloxycarbonyl)-2-(N-methoxy-N-methylcarbamoyl)piperidine
To (RS)-1-(tert-butyloxycarbonyl)-2-piperidine carboxylic acid (5.32 g, 23.2 mmol) in dichloromethane (20 ml) was added sequentially N,O-dimethyl hydroxylamine hydrochloride (2.68 g, 27.5 mmol), triethylamine (12 ml, 86.0 mmol) and py-BOP (13.2 g, 25.4 mmol). The resultant mixture was stirred at ambient temperature for 6 h, then diluted with dichloromethane (350 ml) and poured into 1M HCl (50 ml).
The organic phase was separated and washed with saturated aqueous sodium hydrogen carbonate (3×50 ml) and brine (50 ml) and then evaporated in vacuo, The residue was chromatographed on silica gel eluting with 20% ethyl acetate in hexane to give the title compound as a colourless oil (3.09 g, 49%).
Mass spectrum (API+): 273 (MH+). C13H24N2O4 requires 272.
Description 42: (RS)-1-(tert-butyloxycarbonyl)-2-((5-(4fluorophenyl)-furan-2-yl)carbonyl)piperidine
To a stirred solution of 2-(4-fluorophenyl)-furan (1.8 g, 11.1 mmol) in THF (100 ml) at −35° C. was added n-butyl lithium (2.5M in THF) (4.54 ml, 11.4 mmol) over 3 min. The resultant mixture was stirred for 10 min. at −35° C. and then (RS)-1-(tert-butyloxycarbonyl)-2-(N-methoxy-N-methylcarbamoyl)piperidine (3.09 g, 11.4 mmol) in THF (10 ml) was added over 1 min. The resultant solution was stirred for 15 min. at −35° C. and then poured into saturated ammonium chloride (120 ml) and extracted with ethyl acetate (3×50 ml). The combined organics were washed with saturated aqueous sodium hydrogen carbonate (50 ml) and evaporated in vacuo. The residue was chromatographed on silica gel eluting with 10% ethyl acetate in hexane to give the title compound as a golden oil (3.59 g, 85%).
Mass spectrum (API+): 374 (MH+). C21H24NO4F requires 373.
Description 43: (RS)-2-(5-(4-Fluorophenyl)-furan-2-ylmethyl)-piperidine
To a solution of (RS)-1-(tert-butyloxycarbonyl)-2-((5-(4-fluorophenyl)-furan-2-yl)carbonyl)piperidine (2.0 g, 5.36 mmol) in diethylene glycol (20 g), was added hydrazine hydrate (0.31 ml, 5.36 mmol) and the resultant mixture heated at 100° C. for 30 min. After cooling to room temperature, potassium hydroxide (1.0 g, 17.8 mmol) was added and the mixture heated at 200° C. for 18 h. The reaction mixture was then poured into water (100 ml) and extracted with diethyl ether (3×75 ml). The combined organic extracts were dried (Na2SO4) and evaporated in vacuo to give the title compound as a brown oil (0.88 g, 63%).
Mass spectrum (API+): 260 (MH+). C16H18FNO requires 259.
Description 44: (RS)-2-(2-Oxo-2-phenyl-ethoxycarbonylmethyl)-piperidine-1-carboxylic acid tert butyl ester
2-Carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.86 g) and sodium carbonate (0.62 g) were dissolved in water (30 ml) using gentle warming. A solution of 2-bromoacetophenone (2.33 g) in ethanol (60 ml) was then added and the mixture boiled for 2 h. the mixture was cooled to room temperature and stood for 16 h. The mixture was again boiled for 2 h. solvent removed at reduced pressure and the residue partitioned between water and ethyl acetate. The organic phase was dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 1:1 ethyl acetate:pentane) to give the title compound (3.14 g).
Mass spectrum (API+): 362 (MH+). C19H27NO5 requires 361.
Description 45 (RS)-Piperidin-2-yl-acetic acid 2-oxo-2-phenyl-ethyl ester
The title compound (0.68 g) was prepared from the compound of description 44 (0.80 g) according to the method of description 2.
Mass spectrum (API+): 262 (MH+). C14H18NO5 requires 261.
Descriptions 46-49
The compounds of descriptions 46-49 were prepared from the compound of description 45 (1 mole) and the corresponding carboxylic acid (1 mole) according to the method of description 1
















 










De-





scrip-

yield
Mass Spectrum (Electrospray


tion
Ar2
%
LC/MS)





46




44
Found 464(MH+). C26H26FN3O4.requires 463


 


47




54
Found 465(MH+). C25H25FN4O4.requires 464


 


48




40
Found 416(MH+).C26H25NO4. requires415


 


49




53
Found 474, 476(MH+).C23H24BrNO5.requires 473, 475









Description 50 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-phenyl-2-oxo-ethyl ester
The title compound (0.89 g) was prepared from the acid of description 35 (0.72 g) and 2-bromoacetophenone (0.39 g) by boiling in water/ethanol (15 ml, 1:2) containing sodium carbonate (0.10 g) for 4 h, cooling removing solvent at reduced pressure and partitioning the residue between dichloromethane and water. The organic phase was separated, dried (MgSO4) and solvent removed at reduced pressure.
Mass Spectrum (API+): Found 481 (MH+). C26H25FN2O4S requires 480
Description 51 (RS-(4-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-morpholin-3-yl)-acetic acid ethyl ester
Morpholin-3-ylacetic acid ethyl ester Chem Pharm Bull 94, 31(1), 1983 (2.10 g) was dissolved in dichloromethane (50 ml) and treated with triethylamine (1.33 g). The mixture was cooled (ice bath) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carbonyl chloride (1.53 g) in dichloromethane (10 ml) added. The mixture was stirred for 16 h, diluted with water and the organic phase separated. The aqueous phase was extracted with dichloromethane (2×100 ml), the organic phases combined, dried (Na2SO4) and solvent removed at reduced pressure the residue was column chromatographed (silica gel, 40% ethyl acetate:pentane→60% ethyl acetate pentane eluant) to give the title compound (1.46 g).
Mass Spectrum (API+): Found 393 (MH+). C19H21FN2O4S requires 392.
Description 52 (RS)-(4-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-morpholin-3-yl)-acetic acid
The title compound (1.33 g) was prepared from the compound of description 51 (1.46), according to the method of description 35.
Mass Spectrum (API−): Found 363 [(M-H)−]. C17H17FN2O4S requires 364.
Description 53 (RS)-(4-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-morpholin-3-yl)-acetic acid 2-oxo-2-phenyl-ethyl ester
The title compound (0.57 g) was prepared from the compound of description 52 (0.6 g) and 2-bromoacetophenone (0.33 g) according to the method of description 50.
Mass Spectrum (API+): Found 483 (MH+). C25H23FN2O5S requires 482.
Description 54 (RS)-2-{[2-(4-Fluoro-phenyl)-2-oxo-ethylcarbamoyl]-methyl}-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.77 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (0.80 g) and 2-amino-1-(4-fluoro-phenyl)-ethanone (0.63 g) according to the method of description 20.
Mass Spectrmm (API+): Found 379 (MH+). C21H27FN2O4 requires 378.
Description 55 (RS)-2-[5-(4Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidine
The amide of description 54 (0.77 g) and polyphosphoric acid (10 h) were combined and heated together at 150° C. for 4 h. After cooling to room temperature the reaction mixture was poured onto ice/water and basified to pH 10 with potassium carbonate. The aqueous phase was extracted with dichloromethane, the combined extracts dried (MgSO4) and solvent removed at reduced pressure to give the title compound (0.49 g)
Mass Spectrum (API+): Found 261 (MH+). C15H17FN2O requires 260.
Description 56 (RS)-2-{[2-phenyl-2-oxo-ethylcarbamoyl]-methyl}-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.63 g) was prepared from 2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (0.50 g) and 2-amino-1-phenylethanone (0.35 g) according to the method of description 54.
Mass Spectrum (API+): Found 273 (MH+-C5H9O2). C21H28N2O4 requires 372.
Description 57 (RS)-2-(5-phenyloxazol-2-ylmethyl)-piperidine
The title compound (0.28 g) was prepared from the amide of description 56 (0.40 g) according to the method of description 55.
Mass Spectrum (API+): Found 243 (MH+). C15H18N2O requires 242.
Description 58 (S)-2-[2-(4-Fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-pyrrolidine-1-carboxylic tert butyl ester
The title compound (3.2 g) was prepared from (S)-2-carboxymethyl-pyrrolidine-1-carboxylic acid tert butyl ester (2.02 g) and 2-bromo-4′-fluoroacetophenone (1.91 g) according to the method of description 36.
Mass Spectrum (API+): Found 266 (MH+-C5H9O2). C19H24FNO5 requires 365.
Description 59 (S)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-pyrrolidine-1-carboxylic tert butyl ester
The compound of description 58 (2.2 g) was combined with ammonium acetate (8 g) and warmed to 140° C. for 1.5 h. The reaction mixture was cooled, poured onto saturated potassium carbonate and extracted with dichloromethane (×2). The combined dichloromethane extracts were dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 20% ethyl acetate/pentane→ethyl acetate), the appropriate fractions were combined and solvent removed at reduced pressure to give the title compound (0.81 g).
Mass Spectrum (API+): Found 346 (MH+). C19H24FN3O2 requires 345.
Description 60 5-(4-Fluoro-phenyl)-2-(S)-1-pyrrolidin-2-ylmethyl-1H-imidazole hydrochloride
The compound of description 59 (0.80 g) was dissolved in methanol (20 ml) Ind treated with 4M HCl in dioxane (6 ml). The mixture was stirred for 6 h and then solvent removed at reduced pressure to give the title compound (0.57 g) as a foam.
Mass Spectrum (API+): Found 346 (MHt). C14H15FN3 requires 345.
Description 61 (RS)-2-[2-(4-Fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (3.83 g) was prepared from (RS)-2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.54 g) and 2-bromo-4′-fluoroacetophenone (2.26 g) according to the method of description 36.
Mass Spectrum (API+): Found 308 (MH+-C5H9O2). C20H26FNO5 requires 307.
Description 62 (RS-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (0.80 g) was prepared from the compound of description 61 (1.40 g) according to the method of example 59.
Mass Spectrum (API+): Found 360 (MH+). C20H26FN3O2 requires 359.
Description 63 5-(4Fluoro-phenyl)-2-(RS)-1-piperidine-2-ylmethyl-1H-imidazole hydrochloride
The title compound (0.65 g) was prepared from the compound of description 62 (0.70 g) according to the method of description 60.
Mass Spectrum (API+): Found 346 (MH+). C15H17FN3 requires 345.
Description 64 (RS)-(1-{1-[5(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(2-bromophenyl)-2-oxo-ethyl ester
The title compound (0.51 g) was prepared from the acid of description 35 (0.60 g) and 2-bromo-2′-bromoacetophenone (0.51 g) according to the method of description 36.
Mass Spectrum (API+): Found 559, 561 (MH+). C26H24BrF2N2O4S requires 558, 560
Description 65 (RS)-2-[2-(4-Fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (3.70 g) was prepared from (RS)2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.50 g) according to the method of example 36
Mass Spectrum (API+): Found 380 (MH+). C20H26FNO5 requires 379
Description 66 (RS)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (1.71 g) was prepared from the compound of description 65 (370 g) according to the method of description 59.
Mass Spectrum (API+): Found 366 (MH+). C20H26FN3O2 requires 365
Description 67 (RS)-2-[4Bromo-5-(4-fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The compound of description 66 (0.62 g) was dissolved in DMF (2 ml) containing potassium bicarbonate (0.29 g) and the mixture cooled (ice/salt bath). Bromine (0.15 ml) was added, the mixture stirred for 15 min, poured onto crushed ice and 20% ammonia added to destroy excess bromine. The mixture was extracted with diethyl ether (×3), the combined organic phase washed with water (×3, dried (MgSO4) and solvent removed at reduced pressure to give after chromatography (silica gel, 0→20% ethyl acetate/pentane eluant), the title compound as a gum (0.25 g)
Mass Spectrum (API+): Found 438, 440 (MH+). C20H25BrFN3O2 requires 437, 439
Description 68 (RS)-2-[4-Bromo-5-(4-fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidine hydrochloride
The title compound (0.27 g) was prepared from the compound of description 67 (0.25 g) according to the procedure of description 60.
Mass Spectrum (API+): Found 338, 340 (MH+). C15H17BrFN3 requires 337, 339
Description 69 (RS)-(1-{1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(4-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.74 g) was prepared from piperidin-2-yl-acetic acid methyl ester (0.36 g) and {1-[4-(4-fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]carboxylic acid (0.5 g) according to the method of descriptions 34, 35 and 36.
Description 70 (RS)(1-{1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(4-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.51 g) was prepared from piperidin-2-yl-acetic acid methyl ester (0.38 g) and {1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]carboxylic acid (0.5 g) according to the method of descriptions 34, 35 and 36.
Description 71 (RS)-[1-Quinolin-2-yl-methanoyl)-piperidin-2-yl]-acetic acid 2-(4-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.48 g) was prepared from piperidin-2-yl-acetic acid methyl ester (0.38 g) and quinoline-2-carboxylic acid (0.5 g) according to the method of descriptions 34, 35 and 36.
Description 72 (RS)-2-[2-phenyl-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (7.07 g) was prepared from (RS)-2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (5.0 g) and 2-bromoacetophenone (4.18 g) according to the method of description 36.
Mass Spectrum (API+): Found 262 (MH+-C5H9O2). C20H27NO5 requires 361.
Description 73 (RS)-2-[5-Phenyl-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (3.78 g) was prepared from the compound of description 72 (7.07 g) according to the method of example 59.
Mass Spectrum (API+): Found 242 (MH+-C5H9O2) C20H27N3O2 requires 341.
Description 74 5-Phenyl-2-(RS)-1-piperidine-2-ylmethyl-1H-imidazole
The title compound (0.65 g) was prepared from the compound of description 73 (0.70 g) according to the method of description 60. The hydrochloride salt generated during the reaction was neutralised by dissolving the product in water, neutralising with solid potassium carbonate, extracting with dichloromethane, drying the organic phase (Na2SO4) and removing the solvent at reduced pressure.
Mass Spectrum (API+): Found 242 (MH+). C15H18N3 requires 241.
Description 75 (RS)-2-(2-Oxo-2-phenyl-ethoxycarbonylmethyl)piperidine-1-carboxylic acid benzyl ester
The title compound (4.0 g) was prepared from 2-bromoacetophenone (2.20 g) and 2-carboxymethyl-piperidine-1-carboxylic acid benzyl ester according to the method of description 36
Mass Spectrum (API+): Found 396 (MH+). C23H25NO5 requires 395.
Description 76 (RS)-2-(4-Phenyl-oxazol-2-ylmethyl)-piperidine-1-carboxylic acid benzyl ester
The title compound (0.95 g) was prepared from the compound of description 75 (3.0 g) according to the method of Example 54.
Mass Spectrum (API+): Found 377 (MH+). C23H24N2O3 requires 376.
Description 77 (RS)-2-(4-Phenyl-oxazol-2-ylmethyl)-piperidine
The compound of description 76 (0.097 g) and 10% palladium/charcoal (0.05 g) in ethanol (5 ml) containing cyclohexene (0.5 ml) was heated at 75° C. for 1.5 h, cooled, filtered (kieselguhr) and solvent removed at reduced pressure to give the title compound (0.06 g).
Mass Spectrum (API+): Found 243 (MH+). C15H18N2O requires 242.
Description 78 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid hydrazide
The ester of description 34 (1.06 g) in ethanol (25 ml) was treated with hydrazine hydrate (5 ml) and the mixture boiled for 24 h. Solvent was removed at reduced pressure and the residue column chromatographed (silica gel; 0→10% methanol/dichloromethane). The appropriate fractions were combined and solvent removed at reduced pressure to give the title compound (0.62 g).
Mass Spectrum (API+): Found 377 (MH+). C18H21N4O2S requires 376.
Description 79 (RS)-2-Hydrazinocarbonylmethyl-piperidine-1-carboxylic acid tert butyl ester
The title compound (2.98 g) was prepared from 2-methoxycarbonylmethyl-piperidine-1-carboxylic acid tert butyl ester (3.08 g) according to the method of description 78.
Mass Spectrum (API+): Found 258 (MH+). C12H23N3O3 requires 257.
Description 80 (RS)-2-[5-(4-Fluoro-phenyl)-4H-[1,2,4]triazol-3-ylmethyl]-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.32 g) was prepared from the compound of description 79 (1.49 g) according to the method of example 105.
Mass Spectrum (API+): Found 361 (MH+). C19H25FN4O2 requires 360.
Description 81 (RS)-2-[5 (4-Fluoro-phenyl)-4H-[1,2,4]triazol-3-ylmethyl]-piperidine
The title compound (0.31 g) was prepared from the compound of description 80 (0.32 g) according to the method of description 2.
Mass Spectrum (API+): Found 261 (MH+). C14H17FN4 requires 260.
Description 82 (RS)-2-[2-(3-Methoxy-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (3.06 g) was prepared from (RS)-2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.0 g) and 2-bromo-3′-methoxyacetophenone (1.88 g) according to the method of description 36.
Mass Spectrum (API+): Found 292 (MH+-C5H8O2). C21H29NO6 requires 391.
Description 83 (RS)-2-[5-(3-Methoxy-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (3.78 g) was prepared from the compound of description 82 (3.0 g) according to the method of description 59.
Mass Spectrum (API+): Found 272 (MH+-C5H9O2) C21H29N3O3 requires 371.
Description 84 5-(3-Methoxy-phenyl)-2-(RS)-1-piperidine-2-ylmethyl-1H-imidazole
The title compound (1.06 g) was prepared from the compound of description 83 (1.33 g) according to the method of description 2.
Mass Spectrum (API+): Found 242 (MH+). C15H18N3 requires 241.
Description 85 (RS)-2-[2-(3-Chloro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (2.65 g) was prepared from (RS)-2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.0 g) and 2-bromo-3′-chloroacetophenone (1.92 g) according to the method of description 36.
Mass Spectrum (API+): Found 396, 398 (MH+). C20H26NO5Cl requires 395, 397.
Description 86 (RS)-2-[5-(3-Chloro-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (1.61 g) was prepared from the compound of description 85 (2.65 g) according to the method of description 59.
Mass Spectrum (API+): Found 375, 377 (MH+) C20H25ClN3O2 requires 374, 376.
Description 87 5-(3-Chloro-phenyl)-2-(RS)-1-piperidine-2-ylmethyl-1H-imidazole
The title compound (0.85 g) was prepared from the compound of description 86 (1.05 g) according to the method of description 2.
Mass Spectrum (API+): Found 275, 277 (MH+). C15H17ClN3 requires 274, 276.
Description 88 (RS)-2-[2-(3-Cyano-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (1.51 g) was prepared from (RS)-2-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (1.15 g) and 2-bromo-3′-cyanoacetophenone (1.06 g) according to the method of description 36.
Mass Spectrum (API+): Found 387 (MH+). C21H26N2O5 requires 386.
Description 89 (RS)-2-[5-(3-Cyano-phenyl)-1H-imidazol-2-ylmethyl]-piperidine-1-carboxylic tert butyl ester
The title compound (1.25 g) was prepared from the compound of description 88 (1.50 g) according to the method of description 59.
Mass Spectrum (API+): Found 366 (MH+) C21H25N4O2 requires 365.
Description 90 5-(3-Cyano-phenyl)-2-(RS)-1-piperidine-2-ylmethyl-1H-imidazole
The title compound (0.85 g) was prepared from the compound of description 89 (1.25 g) according to the method of description 2.
Mass Spectrum (API+): Found 266 (MH+). C16H17N4 requires 265.
Description 91 (RS)-1-Benzyl-2-[5-(4fluoro-phenyl)tetrazol-2-ylmethyl]-piperidine
N-Benzyl-2-bromomethylpiperidine (2.1 g), 5-(4-fluoro-phenyl)-2H-tetrazole (1.28 g) and potassium carbonate (6 g) were combined in xylene (100 ml) containing diisopropylethylamine (7 ml) and boiled for 16 h. The reaction mixture was cooled to room temperature, filtered, solvent removed at reduced pressure and the residue column chromatographed (silica gel; diethyl ether/petroleum ether 40:60 eluant) to give after combining appropriate fractions and removing solvent at reduced pressure the title compound 1.44 g.
Mass Spectrum (API+): Found 340 (MH+). C19H22N5F requires 339.
Description 92 (RS)-2-[5-(Fluoro-phenyl)-tetrazol-2ylmethyl]-piperidine
The compound of description 91 (1.4 g) was dissolved in ethanol (100 ml), palladium hydroxide (0.40 g) added and the mixture hydrogenated at 50 psi and 50° C. for 3 h. The mixture was filtered through kieselguhr and solvent removed at reduced pressure and the residue triturated with diethyl ether/petroleum ether to give the title compound as a solid.
Mass Spectrum (API+): Found 250 (MH+). C12H16N5F requires 249.
Description 93 (RS)-1-Benzyl-2-(4-phenyl-imidazol-1-ylmethyl)-piperidine
4-Phenylimidazole (1.3 g) was treated with sodium hydride (0.6 g 50% in oil) in dry tetrahydrofuran (80 ml). When gas evolution had ceased, 2-bromomethyl-N-benzylpiperidine (2.5 g) in tetrahydrofuran (30 ml) was added. The mixture was stirred for 16 h, solvent removed at reduced pressure and treated with ice/water (1:1, 100 ml). The mixture was extracted with dichloromethane (2×), the combined organic phase washed with water, solvent removed at reduced pressure and the residue column chromatographed (silica gel, 0.5→9.5% dichloromethane/methanol). Appropriate fractions were combined to give the title compound 0.72 g.
Mass Spectrum (API+): Found 332 (MH+). C22H25N3 requires 331.
Description 94 (RS)-2-(4-Phenyl-imidazol-1-ylmethyl)-piperidine
The title compound (0.50 g) was prepared from the compound of description 93 (0.70 g) according to the method of description 92.
Mass Spectrum (API+): Found 241 (MH+). C15H19N3 requires 241.
Description 95 (RS)-1-Benzyl-2-[3-(4-fluoro-phenyl)-pyrazol-1-ylmethyl-piperidine
The title compound (0.8 g) was prepared from 2-bromomethyl-N-benzylpiperidine (2.68 g) and 3-(4-fluoro-phenyl)-1H-pyrazole (1.62 g) according to the method of example 93.
Mass Spectrum (API+): Found 350 (MH+). C22H24FN3 requires 349.
Description 96 (RS)-2-[3-(4-Fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidine
The title compound (0.5 g) Was prepared form the compound of description 95 (0.8 g) according to the method of description 94.
Mass Spectrum (API+): Found 260 (MH+). C15H18FN3 requires 259.
Description 97 (RS)-2 Carbamoylmethyl-piperidine-1-carboxylic acid tert butyl ester
The title compound (0.92 g) wvas prepared from 2-(RS)-carboxymethyl-piperidine-1-carboxylic acid tert butyl ester (2.0 g) and ammonium chloride (0.86 g) according to the method of Example 97.
Mass Spectrum (API+): Found 143 (MH+-C5H8O2). C12H22N2O3 requires 242.
Description 98 (RS)-2-Thiocarbamoylmethyl-piperidine-1-carboxylic acid tert butyl ester
The compound of description 97 (0.90 g) and Lawesson's reagent (0.90 g) were combined in dry toluene (30 ml) and heated at 100° C. (oil bath temperature) for 6 h. Solvent was removed at reduced pressure and the residue column chromatographed (silica gel; dichloromethane eluant) to give after combining appropriate fractions the title compound (0.82 g) after tbiturationi with petroleum ether/diethyl ether.
Mass Spectrum (API+): Found 159 (MH+-C5H8O2). C12H22N2O2S requires 258.
Description 99 (RS)-2-(4-Phenyl-thiazol-2-ylmethyl)-piperidine
The compound of description 98 (0.67 g) and 2-bromoacetophenone (0.52 g) were combined in ethanol (20 ml), stirred at room temperature for 8 h and then boiled for 48 h. Solvent was removed at reduced pressure and the residue column chromatographed (silica gel; ethyl acetate/n-pentane→1% ammonia/methanol/dichloromethane) to give the title compound (0.21 g)
Mass Spectrum (API+): Found 259 (MH+). C15H18N2S requires 258.
Description 100 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid hydrazide
The title compound (0.24 g) was prepared from (1-{1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid methyl ester (0.25 g) according to the method of description 17.
Mass Spectrum (API+): Found 377 (MH+). C18H21N4O2FS requires 376.
Description 101 (RS-2,5-Dimethyl-2H-pyrazole-3-carboxylic acid N′-[2-(1-{1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-ethanoyl]-hydrazide
The title compound (0.36 g) was prepared from the compound of description 100 (0.23 g) and 1,3-dimethylpyrazole-5-carboxylic acid according to the method of description 20.
Mass Spectrum (API+): Found 497 (MH+). C24H27N6O3FS requires 498.
Description 102 (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-oxo-1,2-diphenyl-ethyl
The title compound (0.54 g) was prepared from the compound of description 35 (0.40 g) and desyl bromide (0.30 g) according to the method of example 36
Mass Spectrum (API+): Found 557 (MH+). C32H29FN2O4S requires 556.
Description 103 (RS)-2-{2-[N′-(1-Benzofuran-2-yl-methanoyl)-hydrazinol-2-oxo-ethyl}-piperidine-1-carboxylic acid tert butyl ester
The title compound (2.4 g) was prepared from the compound of description 17 and benzofuran-2-carboxylic acid according to the method of description 20.
Mass Spectrum (API+): Found 402 (MH+). C21H27N3O5 requires 401.
Description 104 (RS)-2-(5-Benzofuran-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidine
The title compound (0.77 g) was prepared from the compound of description. 103 according to the method of description 19.
Mass Spectrum (API+): Found 284 (MH+). C16H17N3O2 requires 283.
Description 105 (RS)-2-{1-[5-(4 Fluoro-phenyl)-2-methyl-thiazol4-yl]-methanoyl}-piperidin-2-yl)-acetamide
The compound of description 34 (0.87 g) and formamide (0.3 ml) were combined in tetrahydrofuran and boiled while adding 3 portions of sodium methoxide (0.12 ml each addition, 20% in methanol) over 20 min. After the final addition the reaction was heated for a further 6 h at reflux. The reaction was cooled to room temperature diluted with dichloromethane and water and the aqueous phase separated. The organic phase was washed with water dried (MgSO4) and solvent removed at reduced pressure to give the title compound (1.40 g)
Mass Spectrum (API+): Found 362 (MH+). C18H20FN3O2S requires 361.
Description 106 (RS)-(1-{1-[5-(3,4-Difluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(4fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.435 g) was prepared from the compound of description 35 (0.40 g) and 2-bromo-3′,4′-difluoroacetophenone (0.26 g) according to the method of description 36.
Mass Spectrum (API+): Found 517 (MH+). C24H23F3N2O4S requires 516.
Description 107 (RS)-(1-{[5-(3-Fluoro-pbenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(4-fluoro-phenyl)-2-oxo-ethyl ester
The title compound (0.430 g) was prepared from the compound of description 35 (0.40 g) and 2-bromo-3′-fluoroacetophenone (0.240 g) according to the method of description 36
Mass Spectrum (API+): Found 499 (MH+). C24H24F2N2O4S requires 498.
Description 108. (RS)1-(4-Fluorophenyl)-4-(1-{1-[5-(4 fluorophenyl)-2-methylthiazol-4-yl]methanoyl}-piperidin-2-yl)-butane-1,3-dione


    A. (1-{1-[5(4-fluorophenyl)-2-methylthiazol4-yl]-methanoyl}-piperidin-2-yl)-acetic acid (0.500 g) was dissolved in dry tetrahydrofuran (15 ml) and cooled to −20° C. under an atmosphere of argon. Triethylamine (0.231 ml) and isobutylchloroformate (0.215 ml) were added and the solution was stirred at −20° C. for 1 hour. The solution was then cooled to −78° C.
    B. A solution of 4′-fluoroacetophenone (0.229 g) in THF (15 ml) was cooled to −20° C. under an atmosphere of argon. A solution of lithium diisopropylamide (0.830 ml; 2M solution in THF) was added and stirring continued at −20° C. for 30 minutes. The solution was then cooled to −78° C.
    C. The solution from part B was added to the stirred solution of part A by way of a cannula. Stirring was continued at −78° C. under an atmosphere of argon for 2 hours before being quenched by the addition of saturated ammonium chloride solution. After reaching room temperature, the reaction solution was partitioned between ethyl acetate and water. The organic solution was washed with brine dried (MgSO4) and evaporated. The residue was chromatographed over silica gel, eluting with a gradient of 10 to 75% ethyl acetate in hexane. The title compound was obtained as a colourless oil (0.560 g) mass spectrum (API+) 483 [MH+], (API−) 481 [(M−H)−] C26H24F2N2O3S requires 482.


Description 109. (RS)-2-Carboxymethylpiperazine-1,4-dicarboxylic acid 4-tert-butyl ester 1-(9H-fluoren-9-ylmethyl) ester
3-Methoxycarbonylmethylpiperazine-1-carboxylic acid tert-butyl ester (6.0 g) was dissolved in TBF (60 ml) and 1N sodium hydroxide solution (60 ml) and stirred at room temperature for 6 hours. The solution was then cooled to 5° C. and adjusted to pH 9-10 by the addition of 10% hydrochloric acid. Nα(9-Fluorenylmethoxycarbonyl chloride (6.05 g) was then added portionwise, maintaining the pH at 9-10 by the addition of 1N NaOH solution. The reaction mixture was stirred at 5° C. for 16 hours. The solution was then adjusted to pH 1 by the addition of 10% hydrochloric acid. The solution was extracted with ethyl acetate (×2), dried (MgSO4) and evaporated. The title compound was obtained as a white foam (9.96 g), mass spectrum (API+) 411 [(M-C4H8)H+], C26H30N2O6 requires 466.
Description 110 (RS)-3-[2-(4-Fluorophenyl)-2-oxo-ethoxycarbonylmethyl]piperazine-1-carboxylic acid tert-butyl ester
(RS)-2-Carboxymethylpiperazine-1,4-dicarboxylic acid 4-tert-butyl ester 1-(9H-fluoren-9-ylmethyl) ester from description 109 (2.0 g) was dissolved in DMF (25 ml) and stirred at room temperature under argon for 3 days in the presence of potassium carbonate (0.697 g) and 2-bromo-4′-fluoroacetophenone (0.930 g). The reaction solution was then partitioned between ethyl acetate and water the organic solution was washed with brine, dried (MgSO4) and evaporated. The crude product was chromatographed over silica gel, eluting with 25 to 100% ethyl acetate in hexane, followed by 10% ethanol in ethyl acetate. The title compound was obtained as a pale yellow solid (0.887 g), mass spectrum (API+) 381 [MH+], C19H25FN2O5 requires 380.
Description 111. (RS)-4-{1-[5-(4-Fluorophenyl)-2-methylthiazol-4-yl]-methanoyl}-3-[2-(4-fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperazine-1-carboxylic acid tert-butyl ester
(RS)-3-[2-(4-Fluorophenyl)-2-oxo-ethoxycarbonylmethyl]-piperazine-1-carboxylic acid tert-butyl ester description 110 (0.887 g) was reacted with HATU (0.932 g), diisopropylethylamine (1.30 ml) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.707 g) in dry DMF (8 ml) according to the method of description 20. Silica gel column chromatography, eluting with ethyl acetate-hexane mixtures provided the title compound as a white foam (1.168 g), mass spectrum (API+) 600 [MH+], C30H31F2N3O6S requires 599.
Description 112. (RS)-3-[4-(4-Fluorophenyl-1H-imidazol-2-ylmethyl]-4-{1-[5-(4-fluorophenyl)-2-methylthiazol-4-yl]-methanoyl}-piperazine-1-carboxylic acid tert-butyl ester
(RS)-4-{1-[5-(4-Fluorophenyl)-2-methylthiazol-4-yl]-methanoyl}-3-[2-(4-fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperazine-1-carboxylic acid tert-butyl ester from description 111 (0.360 g) and anhydrous ammonium acetate were heated to 140° C. under argon for 1.5 hours with stirring. After cooling, the reaction mixture was partitioned between dichloromethane and saturated potassium carbonate solution. The organic solution was washed with brine, dried (MgSO4) and evaporated. The residue was chromatographed over silica gel, eluting with 0 to 10% ethanol in ethyl acetate. The title compound was obtained as a white foam (0.125 g), mass spectrum (API+) 580 [MH+], C30H31F2N5O3S requires 579.
Description 113. (RS)-4-{1-[5-(4-Fluorophenyl)-2-methylthiazol-4-yl]-methanoyl}-3-[4-(4-fluoro-phenyl)-oxazol-2-ylmethyl]-piperazine-1-carboxylic acid tert-butyl ester
(RS)-4-{1-[5(4-Fluorophenyl)-2-methylthiazol4-yl]-methanoyl}-3-[2-(4-fluoro-phenyl)-2-oxo-ethoxycarbonylmethyl]-piperazine-1-carboxylic acid tert-butyl ester, description 111 (0.385 g), tert-butyl carbamate (0.376 g) and boron trifluoride etherate (4 drops) were dissolved in xylene (5 ml) and heated to 140° C., under argon and with stirring for 48 hours. After cooling, the reaction mixture was partitioned between ethyl acetate and saturated sodium hydrogen carbonate solution. The organic layer was dried (MgSO4), evaporated and the residue chromatographed over silica gel. Elution with a gradient of 25 to 100% ethyl acetate in hexane provided the title compound as a pale yellow oil (0.130 g), mass spectrum (API+) 581 [MH+], C30H30F2N4O4S requires 580.
Description 114. (S)-2-Methoxycarbonylmethyl-pyrrolidine-1-carboxylic acid tert-butyl ester
A solution of (S)-2-carboxymethyl-pyrrolidine-1-carboxylic acid tert-butyl ester (2.00 g) in methanol (1.32 ml)/acetonitrile (40 ml) was treated with N,N-diisopropylethylamine (1.78 ml). Trimethylsilyldiazomethane, (2M, 8.73 ml) was added dropwise and the resulting mixture was stirred at room temperature, under argon for 24 h. The mixture was diluted with ethyl acetate, washed with 2M HCl, saturated aqueous sodium hydrodgen carbonate, brine then dried (magnesium sulfate). The solvent was removed under reduced pressure to afford the title compound (2.10 g)
Mass Spectrum (API+): 144 (MH+-tBOC). C12H21NO4 requires 243.
Description 115. (S)-2-Hydrazinocarbonylmethyl-pyrrolidine-1-carboxylic acid tert-butyl ester
The ester of description 114 (2.10 g) was treated with hydrazine hydrate (16.3 ml) as described in description 78 to afford the title compound (1.60 g).
Mass Spectrum (API+): 144 (MH+-tBOC). C11H21N3O3 requires 243.
Description 116. (S)-2-(5-Phenyl-4H-[1,2,4]triazol-3-ylmethyl)-pyrrolidine-1-carboxylic acid tert-butyl ester
Benzamidine.hydrochloride (0.84 g) in ethanol (20 ml) was treated with 25% sodium methoxide solution in methanol (2.44 ml) and stirred for 45 min. at room temperature under argon. The hydrazide of description 115 (1.3 g) was added and the mixture was heated at reflux for 24 h. After cooling the solvent was removed under reduced pressure then the residue was partitioned between dichloromethane and water. The organic phase was dried (MgSO4) and the solvent removed under reduced pressure. The residue was column chromatographed (silica gel; 0→50% ethyl acetate-pentane) to afford the title compound (0.26 g).
Mass Spectrum (API+): 329 (MH+). C18H24N4O2 requires 328.
Description 117.3-Phenyl-5-(S)-1-pyrrolidin-2-ylmethyl-4H-[1,2,4]triazole
The compound of description 116 (0.13 g) was treated with trifluoroacetic acid (2.5 ml) according to a method similar to that of description 2 to afford the title compound (0.09 g).
Mass Spectrum (API+): 229 (MH+). C13H16N4 requires 228.
Description 118. (S)-2-(2-Oxo-2-phenyl-ethoxycarbonylmethyl)-pyrrolidine-1-carboxylic acid benzyl ester
The title compound (0.700 g) was prepared from (S)-2-carboxymethyl-pyrrolidine-1-carboxylic acid benzyl ester (1.00 g, Aoyama et al, Chem. Pharm. Bull., 3249, 29,11,1981) and 2-bromoacetophenone (0.760 g) according to the method of description 36.
Mass Spectrum (API+): 382 (MH+). C22H23NO5 requires 381.
Description 119. (S)-2(4-Phenyl-oxazol-2-ylmethyl)-pyrrolidine-1-carboxylic acid benzyl ester
The title compound (0.290 g) was prepared from the compound of description 118 (0.700 g) according to the method of example 54 using xylene as solvent.
Mass Spectrum (API+): 363 (MH+). C22H22N2O3 requires 362.
Description 120. 4-Phenyl-2-(S)-1-pyrrolidin-2-ylmethyl-oxazole
The title compound (0.065 g) was prepared by treating the compound of description 119 (0.280 g) with 10% palladium/charcoal (0.150 g, 50% paste) according to the method of description 77. The product was purified by column chromatography (silica gel, 0→4% (10% 0.880 ammonia-methanol)-dichloromethane).
Mass Spectrum (API+): 229 (MH+). C14H16N2O requires 228.
Description 121. (RS)-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-yl)-acetic acid 2-(2-bromo-phenyl)-2-oxo-ethyl ester
The title compound (3.0 g) was prepared as a brown oil from the acid of description 35 (2.5 g) and (2-bromo-phenyl)-acetyl bromide (1.92 g) according to the method of description 36.
Mass Spectrum (API+): Found 559,561 (MH+). C26H24BrFN2O4S requires 558,560.
Description 122. (RS)-2-[4-(2-Fluoro-phenyl)-thiazol-2-ylmethyl]-piperidine
The title compound (0.335 g) was prepared as an oil from the compound of description 98 (0.750 g) and 2-bromo-1-(2-fluoro-phenyl)ethanone (0.631 g) according to the method of description 99.
Mass Spectrum (API+): Found 277. (MH+). C15H17FN2S requires 276.
Description 123. (RS)-2-[4-(3-Fluoro-phenyl)-thiazol-2-ylmethyl]-piperidine
The title compound (0.310 g) was prepared as an oil from the compound of description 98 (0.750 g) and 2-bromo-1-(3-fluoro-phenyl)-ethanone (0.631 g) according to the method of description 99.
Mass Spectrun (API+): Found 277. (MH+). C15H17FN2S requires 276.


EXAMPLE 1
(RS)-1-[5-(4 Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylwethyl)-piperidin-1-yl]-methanone
2-Methyl-5-(4-fluorophenyl)-thiazole-4-carboxylic acid (0.07 g), [O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate] (0.12 g) and diisopropylaethylamine (0.17 ml) in dimethylformamide (5 ml) was stirred for 15 min. The amine of D2 (0.075 g) was added and the mixture stirred for 16 h. Solvent was removed at reduced pressure, the residue dissolved in ethyl acetate and washed with water. The organic phase was separated dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica get, 0-100% ethyl acetate/pentane) to give the title compound (0.095 g).
Mass Spectrum (API+): Found 463 (MH+). C25H23FN4O2S requires 462.
EXAMPLE 2
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone
A mixture of 5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazole-4-carbonyl chloride (0.11 5 g) and the amine D2 were combined in dichloromethane (10 ml) containing triethyl amine (0.2 ml). The mixture was stirred for 16 h, washed with water, the organic phase dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica get, 40-60% ethyl acetate/pentane eluant) to give the title compound (0.154 g).
Mass Spectrum (API+): Found 447 (MH+). C24H23FN6O2 requires 446.
The compounds of the examples of Table 1 were prepared by analogous procedures to those used to prepare the compounds of Example 1 and Example 2 from the corresponding amine and carboxylic acid (Method 1) or from the corresponding amine and acid chloride Method 2).







TABLE 1







5-Aryl-[1,3,4]oxadiazol-2-ylpiperidines








 



















Mass Spectrum


Example
Amine
Method
Ar2
R2
yield %
(Electrospray LC/MS)
















3
D2
1








56
Found 430(MH+).C24H23N5O3.requires 429


 


4
D2
2








86
Found 398(MH+).C25H23N3O2.requires 397


 


5
D2
2








79
Found 446(MH+).C25H24FN5O2.requires 445


 


6
D2
2








64
Found 446(MH+).C25H24FN5O2.requires 445


 


7
D2
2








42
Found 446(MH+).C25H24FN5O2.requires 445


 


8
D2
2








53
Found 432(MH+).C24H22FN5O2.requires 431


 


9
D4
1








56
Found 448(MH+).C24H22FN5O2.requires 447


 


10
D4
1








77
Found 481(MH+).C25H22F2N4O2S.requires 480


 


11
D6
1








54
Found 497, 499(MH+).C25H22ClFN4O2S.requires 496, 498


 


12
D6
1








57
Found 464, 466(MH+).C24H22ClN5O3.requires 463, 465


 


13
D8
1








59
Found 464(MH+).C24H22FN5O2S.requires 463


 


14
D10
1








64
Found 481(MH+).C25H22F2N4O2S.requires 480


 


15
D12
1








71
Found 497, 499(MH+).C25H22ClFN4O2S.requires 496, 498


 


16
D14
2








79
Found 497, 499(MH+).C25H22ClFN4O2S.requires 496, 498


 


17
D14
2








7
Found 464, 466(MH+).C24H22ClN5O3.requires 463, 465


 


18
D16
2








62
Found 532, 534,466(MH+).C25H21Cl2FN4O2S.requires 531, 533


 


19
D19
1








63
Found 481(MH+).C25H22F2N4O2S.requires 480


 


20
D21
1








6
Found 503(MH+).C27H23FN4O3S.requires 502


 


21
D19
1








52
Found 464(MH+).C25H23F2N5O2.requires 463


 


22
D19
1








44
Found 465(MH+).C24H22F2N6O2.requires 464


 


23
D19
1








50
Found 416(MH+).C25H22FN3O2.requires 415


 


24
D23
1








69
Found 499(MH+).C25H21F3N4O2S.requires 498


 


25
D2
1








54
Found 446(MH+).C25H24FN5O2.requires 445


 


26
D25
1








56
Found 499(MH+).C25H21F3N4O2S.requires 498


 


27
D25
1








50
Found 468(MH+).C24H20F3N5O2.requires 467


 


28
D25
1








44
Found 482(MH+).C25H22F3N5O2.requires 481


 


29
D27
1








69
Found 499(MH+).C25H21F3N4O2S.requires 498


 


30
D27
1








65
Found 485(MH+).C24H19F3N4O2S.requires 484


 


31
D27
1








56
Found 468(MH+).C24H20F3N5O2.requires 467


 


32
D27
1








44
Found 482(MH+).C25H22F3N5O2.requires 481


 


33
D29
2








44
Found 478(MH+).C25H24FN5O2S.requires 477


 


34
D29
2








23
Found 447(MH+).C24H23FN6O2.requires 446


 


35
D29
2








29
Found 461(MH+).C25H25FN6O2.requires 460


 


36
D4
2








77
Found 467(MH+).C24H20F2N4O2S.requires 466


 


37
D31
2








40
Found 453(MH+).C23H21FN4O3S.requires 452


 


38
D31
2








45
Found 422(MH+).C22H20FN5O3.requires 421


 


39
D31
2








50
Found 436(MH+).C23H22FN5O3.requires 435


 


40
D31
2








53
Found 437(MH+).C22H21FN6O3.requires 436


 


41
D4
2








77
Found 467(MH+).C24H20F2N4O2S.requires 466


 


42
D4
1








69
Found 481(MH+).C25H22F2N4O2S.requires 480


 


43
D4
2








85
Found 481(MH+).C25H22F2N4O2S.requires 480


 


44
D2
2








76
Found 449(MH+).C24H21FN4O2S.requires 448


 


45
D2
1








69
Found 463(MH+).C25H23FN4O2S.requires 462


 


46
D2
2








80
Found 463(MH+).C25H23FN4O2S.requires 462


 


47
D29
1








27
Found 478(MH+).C25H24FN5O2S.requires 477


 


48
D29
2








80
Found 478(MH+).C25H24FN5O2S.requires 477


 


49
D23
1








69
Found 468(MH+).C24H20F3N5O2.requires 467


 


50
D23
1








72
Found 482(MH+).C25H22F3N5O2.requires 481


 


181
D23
1








64
Found 483(MH+).C24H21F3N6O2.requires 482


 


125
D4
1









Found 448(MH+).C25H22FN3O2S.requires 447


 


126
D4
1









Found 448(MH+).C25H22FN3O2S.requires 447


 


127
D4
1









Found 432(MH+).C24H22FN5O2.requires 431


 


128
D4
1









Found 467(MH+).C28H23FN4O2.requires 466


 


129
D4
1









Found 472(MH+).C28H26FN3O3.requires 471


 


130
D4
1









Found 431(MH+).C25H23FN4O2.requires 430


 


131
D4
1









Found 456(MH+).C27H22FN3O3.requires 455


 


132
D4
1









Found 410(MH+).C23H24FN3O3.requires 409


 


133
D4
1









Found 424(MH+).C24H26FN3O3.requires 423


 


134
D4
1









Found 465(MH+).C22H20Cl2FN3O3.requires 464


 


135
D4
1









Found 446(MH+).C26H24FN3O3.requires 445


 


136
D4
1









Found 463(MH+).C26H27FN4O3.requires 462


 


137
D4
1









Found449(MH+).C25H25FN4O3.requires 448


 


138
D4
1









Found517(MH+).C28H25FN4O5.requires 516


 


139
D4
1









Found 501(MH+).C28H25FN4O4.requires 500


 


140
D4
1









Found 487(MH+).C27H23FN4O4.requires 486


 


141
D4
1









Found 406(MH+).C23H20FN3O3.requires 405


 


142
D4
1









Found 502, 504(MH+).C24H25BrFN3O3.requires 501,503


 


143
D2
1








85%
Found 460(MH+).C26H26FN5O2.requires 459









EXAMPLE 51
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-pyrrolidin-1-yl]-methanone
The title compound (0.01 g) was prepared from the amine of description 33 (0.069 g) and 2-methyl-5-(4-fluorophenyl)-thiazole-4-carboxylic acid (0.07 g) according to the method of example 1.
Mass Spectrum (API+):.
The compounds of the examples of Table 2 were prepared by analogous procedures to those used to prepare the compounds of example 51







TABLE 2







Pyrrolidine Aryl oxadiazoles








 

















Mass


Ex-




Spectrum


am-
A-


yield
(Electrospray


ple
mine
Ar2
R2
%
LC/MS)





52
D33








46
Found449(MH+).C24H21FN4O2Srequires 448


 


53
D33








24
Found449(MH1).C24H21FN4O2Srequires 448









EXAMPLE 54
(RS)-R-[5-(4 Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(4-fluoro-phenyl)-oxazol -2-ylmethyl]-piperidin-1-yl}-methanone
Boron trifluoride diethyl etherate (4 drops) was added to a mixture of the ester of description 36 (0.264 g) and acetamide (0.156 g) in diethyl ether (2 ml). Xylene (1 ml) was added and the mixture heated to 140° C. for 22 h. The reaction mixture was cooled to room temperature, diluted with ethyl acetate and washed with water and brine. The organic phase was dried (MgSO4) and solvent removed at reduced pressure the residue was column chromatographed (silica gel, 0→60% ethyl acetate/pentane eluant) to give the title compound (0.145 g)
Mass Spectrum (API+): Found 480 (MH+). C26H23F2N3O2S requires 479
The compounds of the examples of Table 3 were prepared by analogous procedures to those used to prepare the compound of example 54







TABLE 3







Piperidine 2-(4-aryloxazoles)








 

















Mass Spectrum







(Electrospray


Example
Ester
Ar2
R2
yield %
LC/MS)















55
D37








67
Found 492(MH+).C27H26FN3O3Srequires 491


 


56
D38








15
Found 480(MH+).C26H23F2N3O2Srequires 479


 


57
D39








46
Found 480(MH+).C26H23F2N3O2Srequires 479


 


60
D46








43
Found 445(MH+).C26H25FN4O2requires 444


 


61
D47








16
Found 446(MH+).C25H24FN5O2requires 445


 


62
D48








22
Found 397(MH+).C26H24N2O2requires 396


 


63
D49








39
Found 455, 457(MH+).C23H23BrN2O3requires 454, 456


 


70
D50








85
Found 462(MH+).C26H24FN3O2Srequires 461


 


99
D69








46
Found 463(MH+).C26H24F2N4O2requires 462


 


100
D70








30
Found 416(MH+).C25H22F2N4O2requires 415


 


101
D71








30
Found 416(MH+).C25H22FN3O2requires 415









EXAMPLE 58
(RS)-1-[5(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-methyl-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.28 g) was prepared from the ester of description 40 (0.30 g) according to the method of example 54.
Mass Spectrum (API+): Found 476 (MH+). C27H26FN3O2S requires 475
EXAMPLE 59
(RS)-2-(5-(4-Fluorophenyl)-furan-2-ylmethyl)-1-((5-(4-fluorophenyl)-2-methyl-thiazol-4-yl)carbonyl-piperidine
5-(4-Fluorophenyl)-2-methyl-thiazole-4-carbonyl chloride (115 mg, 0.425 mmol) in dichloromethane (1 ml) was added to a solution of (RS)-2-(5-(4-fluorophenyl)-furan-2-ylmethyl)-piperidine (100 mg, 0.386 mmol) and triethylamine (0.16 ml, 1.16 mmol) in dichloromethane (4 ml) and the mixture shaken at ambient temperature for 30 min. The reaction mixture was then washed with saturated aqueous sodium hydrogen carbonate (8 ml) and the organic layer applied directly onto a pre-packed silica gel column and chromatographed eluting with an ethyl acetate-hexane gradient to give the title compound as a yellow solid (78.0 mg, 42%).
Mass spectrum (API+): 479 (MH+): C27H24F2N2O2S requires 478.
EXAMPLE 64
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-1H-imidazol-2-ylmethyl)-piperidin-1-yl]-methanone
The compound of description 50 (0.30 g), ammonium acetate (0.38 g) and n-butanol (5 ml) were combined and boiled for 1 h. Solvent was removed at reduced pressure and the residue column chromatographed (silica gel, ethyl acetate then 3% methanol/ethyl acetate) to give the title compound (0.13 g).
Mass Spectrum (API+): Found 461 (MH+). C26H25FN4OS requires 460.
EXAMPLE 65
(RS)-1-[5-(4-Fluoro-phenyl)-2methyl-thiazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-[1,2,4]oxadiazol-5-ylmethyl]-piperidin-1-yl}-methanone
The acid of description 35 (0.14 g) was dissolved in dichloromethane (10 mi) containing dimethylformamide (1 drop). Oxalyl chloride (0.04 g) was added and the mixture stirred for 3 h. Solvent was removed at reduced pressure, the residue redissolved in dichloromethane (10 mI) and added to a solution of 4-fluorobenzanidoximo (0.06 g) in pyridine (0.3 ml). The mixture was stirred at room temperature for 10 min and boiled for 5 h. Solvent was removed at reduced pressure and the residue column chromatographied (silica gel, 20% ether in pentane→dichloromethane eluant) to give the title compound (0.03 g).
Mass Spectrum (API+): Found 481 (MH+). C25H22F2N4O2S requires 480.
EXAMPLE 66
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-morpholin-4-yl]-methanone
The title compound (0.29 g) was prepared from the compound of description 52 and 5-phenyltetrazole (0.10 g) according to the method of description 1.
Mass Spectrum (API+): Found 465 (MH+). C24H21FN4O3S requires 464.
EXAMPLE 67
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-methanone
The title compound (0.131 g) was prepared from the compound of description 53 (0.2 g) according to the method of example 54.
Mass Spectrum (API+): Found 464 (MH+). C25H22FN3O3S requires 463.
EXAMPLE 68
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-1H-imidazol -2-ylmethyl)-morpholin-4yl]-methanone
The title compound (0.09 g) was prepared from the compound of description 53 (0.20 g) according to the method of example 64.
Mass Spectrum (API+): Found 463 (MH+). C25H23FN4O2S requires 462.
EXAMPLE 69
1-[5-(4-Fluoro-plenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl) -oxazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.11 g) was prepared from the amine of description 55 (0.08 g) and 2-methyl-5-(4-fluorophenyl)-thiazole-4-carboxylic acid (0.07 g) according to the method of description 20.
Mass Spectrum (API+): Found 480 (MH+). C26H23F2N3O2S requires 479.
The compounds of the examples of Table 4 were prepared by analogous procedures to those used to prepare the compound of example 69.







TABLE 4







Piperidine 2-(5-aryloxazoles)








 

















Mass Spectrum


Example
Amine
Ar2
R2
yield %
(Electrospray LC/MS)





71
D55








62
Found 415(MH+).C26H23FN2O2requires 414


 


72
D55








58
Found 425(MH+).C24H25FN2O4requires 424


 


73
D55








60
Found 463(MH+).C26H24F2N4O2requires 462


 


74
D55








58
Found 462(MH+).C25H23F2N5O2requires 461


 


75
D55








63
Found 463(MH+).C26H24F2N4O2requires 462


 


77
D57








56
Found 462(MH+).C26H24FN3O2Srequires 461


 


78
D57








44
Found 429(MH+).C25H24N4O3requires 428


 


79
D57








42
Found 473(MH+).C22H21IN2O2requires 472









EXAMPLE 76
(RS)-1-{2-[5-(4-Fluoro-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-thiazol-4-yl]-methanone
The title compound was prepared from the compound of description 55 (0.07 g) and 5-(4-fluorophenyl)-thiazole-4-carboxylic acid chloride (0.06 g) according to the method of example 2.
Found 466 (MH+). C25H21F2N3O2S requires 465.
EXAMPLE 80
1-{(S)-2-[5-(4-Fluoro-phenyl)-1H-imidazol-2-ylmethyl]-pyrrolidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The title compound (0.09 g)-was prepared from the amine of description 60 (0.092 g) (0.08 g) and 2-methyl-5-(4-fluorophenyl)-thiazole-4-carboxylic acid (0.07 g) according to the method of description 20.
Mass Spectrum (API+): Found 465 (MH+). C25H22F2N4OS requires 464.
The compounds of the examples of Table 5 were prepared by analogous procedures to those used to prepare the compound of example 80.







TABLE 5







Piperidine and pyrrolidine 2-(4-arylimidazoles)








 



















Mass Spectrum


Example
Amine
n
Ar2
R2
yield %
(Electrospray LC/MS) API+





81(S)*
60
bond








72
Found 448(MH+).C25H23F2N5OS requires 447


 


82(S)*
60
bond








75
Found 434(MH+).C24H21F2N5OS requires 433


 


83
63
1








42
Found 479(MH+).C26H24F2N4OS requires 478


 


84
63
1








59
Found 462(MH+).C26H25F2N5Orequires 461


 


85
63
1








45
Found 448(MH+).C25H23F2N5Orequires 447


 


86
63
1








72
Found 395(MH+).C22H23FN4O2requires 394


 


87
63
1








28
Found 415(MH+).C25H23FN4Orequires 414


 


88
63
1








24
Found 416(MH+).C24H22FN5Orequires 415


 


89
63
1









Found 519(MH+).C29H32F2N6Orequires 518


 


90
63
1









Found 495(MH+).C26H24F2N4O2S requires 494


 


91
63
1









Found 463(MH+).C25H24F2N6Orequires 462


 


92
63
1









Found 446(MH+).C25H24FN5O2requires 445


 


104
74
1








18
Found 477(MH+).C26H25FN4O2S requires 476


 


108
84
1








53
Found 491(MH+).C27H27FN4O2S requires490.Isolated as theHCl salt


 


109
84
1








35
Found 474(MH+).C27H28FN5O2requires473 Isolated asthe HCl salt


 


110
87
1








60
Found496(MH+).C26H2437ClFN4OSrequires495Isolatedas the HClsalt


 


111
87
1








55
Found 480(MH+).C26H2537ClFN5O requires479 Isolatedas the HClsalt


 


112
90
1








25
Found 486(MH+).C27H24FN5OSrequires 485Isolated as theHCl salt


 


113
90
1








25
Found 469(MH+).C27H25FN6Orequires 468Isolated as theHCl salt


 


114
74
1









MassSpectrumFound 461(MH+).C26H25FN4OSrequires 460.


 


115
74
1









MassSpectrumFound 461(MH+).C26H25FN4OSrequires 460.


 


116
74
1









MassSpectrumFound 433(MH+).C26H26N4OSrequires 432.


 


117
74
1









MassSpectrumFound 544(MH+).C31H37N5O2Srequires 543.


 


118
74
1









MassSpectrumFound 558(MH+).C32H39N5O2Srequires 557.


 


119
74
1









MassSpectrumFound 530(MH+).C30H35N5O2Srequires 529.


 


159
106
1








34%
MassSpectrumFound 497(MH+).C26H23F3N4OSrequires496.


 


160
107
1








34%
MassSpectrumFound 479(MH+).C26H24F2N4OSrequires478.





(S)* against the Example number indicates that the Example was prepared as the (S) enantiomer.






EXAMPLE 93
(RS)-1-[5-(4Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-methoxyphenyl) -1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.17 g) was prepared from the compound of description 37 (0.50 g) according to the method of description 59.
Found 491 (MH+). C27H27FN4O2S requires 490.
EXAMPLE 94
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-fluorophenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.035 g) was prepared from the compound of description 39 (0.21 g) according to the method of description 59.
Found 479 (MH+). C26H24F2N4OS requires 478.
EXAMPLE 95
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(2-bromophenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.18 g) was prepared from the compound of description 64 (0.50 g) according to the method of description 59.
Found 539, 541 (MH+) C26H24BrFN4OS requires 538, 540
EXAMPLE 96
(RS)-2-[2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-ylmethyl)-3H-imidazol-4-yl]-benzonitrile
The compound of example 95 (0.11 g) and copper(I) cyanide (0.03 g) were combined in N-methylpyrrolidinone (5 ml) and the mixture boiled for 6 h. After cooling to room temperature the reaction mixture was stood overnight, diluted with ethyl acetate, passed through silica gel eluting with ethyl acetate/water. The organic phase was separated washed with water dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 20→100% ethyl acetate/pentane), the appropriate fractions combined and solvent removed at reduced pressure to give the title compound (0.03 g) as a gum
Found 485 (MH+) C27H24FN5OS requires 486.
EXAMPLE 97
(RS)-1-{2-[4-Bromo-5(4-fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol4-yl]-methanone
The title compound (0.17 g) was prepared by treating the compound of description 68 (0.27 g), 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.19 g), 1-hydroxybenzotriazole (0.05 g) and diisopropylethylamine ((0.35 ml) in dimethylformamide (5 ml) with EDC.HCl. The mixture was stirred for 20 h, diluted with diethyl ether and washed with sodium carbonate and water (×3), dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 0→2% methanol/dichloromethane), the appropriate fractions combined and solvent removed at reduced pressure to give the title compound (0.17 g) as a gum
Found 557, 559 (MH+) C26H23 BrF2N4OS requires 556, 558.
EXAMPLE 98
(RS)-5-(4-Fluoro-phenyl)-2-(1-{1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-ylmethyl)-3H-imidazol-4-carbonitrile
The title compound (0.038 g) was prepared from the compound of example 97 (0.22 g) according to the method of example 96.
Found 504 (MH+) C27H23F2N5OS requires 503.
EXAMPLE 102
(RS)-1-(2-Ethoxy-phenyl)-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.065 g) was prepared from the compound of description 77 (0.060 g) and 2-ethoxybenzoic acid (0.042 g) according to the method of example 1
Found 391 (MH+) C24H26N2O3 requires 390.
EXAMPLE 103
(RS)-1-[5-(4-Fluoro-phenyl)-2-hydroxymethyl-thiazol-4-yl]-1-[2-(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.055 g) was prepared from the compound of description 77 (0.15 g) and 5-(4-fluoro-phenyl)-2-hydroxymethyl-thiazole4-carboxylic acid (0.042 g) according to the method of example 97
Found 478 (MH+) C26H24FN3O3S requires 477.
EXAMPLE 105
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-4H-[1,2,4]triazol-3-ylmethyl]-piperidin-1-yl}-methanone
A solution of the compound of description 78 (0.20 g) and 4-fluorobenzamidine (0.11 g) in ethanol (5 ml) was treated with a 25% sodium methoxide in methanol solution (0.24 ml) and the mixture refluxed for 60 h. Solvent was removed at reduced pressure, the residue partitioned between dichloromethane/water, the organic phase separaeted, dried (MgSO4) and solvent removed at reduced pressure to give the title compound (0.04 g)
Found 480 (MH+) C25H23F2N5OS requires 479.
EXAMPLE 106
(RS)-1-{2-[5(4-Fluoro-phenyl)-4H-[1,2,4]triazol-3-ylmethyl]-piperidin-1-yl}-1-isoquinolin-3-yl-methanone
The title compound (0.006 g) was prepared from the compound of description 81 (0.08 g) and isoquinoline-3-carboxylic acid (0.06 g) according to the method of description 20.
Found 416 (MH+) C24H22FN5O requires 415.
EXAMPLE 107
(RS)-1-{2-[3(3-Dimethylamino-propoxy)-phenyl]-thiophen-3-yl}-1-{2-[4-(4-fluoro-phenyl)-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.006 g) was prepared from the compound of description 63 (0.071 g) and 2-[3-(3-Dimethylamino-propoxy)-phenyl]-thiophene-3-carbonyl chloride
Found 547 (MH+) C31H35FN4O2S requires 546.
EXAMPLE 120
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[5-(4-fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.14 g) was prepared from the compound of description 92 (0.09 g) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.08 g) according to the method of Description 20.
Found 481(MH+) C24H22F2N6OS requires 480.
EXAMPLE 121
(RS)-1-{2-[5-(4-Fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-thiazol-4-yl]-methanone
The title compound (0.13 g) was prepared from the compound of description 92 (0.09 g) and 5-(4-fluoro-phenyl)-thiazole-4-carboxylic acid (0.074 g) according to the method of Description 20.
Found 467(MH+) C23H20F2N6OS requires 466.
EXAMPLE 122
(RS)-1-[4-(4-Fluoro-phenyl)-1H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.10 g) was prepared from the compound of description 92 (0.09 g) and 4-(4-Fluoro-phenyl)-1H-pyrazole-3-carboxylic acid (0.070 g) according to the method of Description 20.
Found 450 (MH+) C23H21F2N7O requires 449.
EXAMPLE 123
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.13 g) was prepared from the compound of description 92 (0.09 g) and 4-(4-Fluoro-phenyl-1-methyl-1H-pyrazole-3-carboxylic acid (0.070 g) according to the method of Description 20.
Found 464(MH+) C24H23F2N7O requires 463.
EXAMPLE 124
(RS)-1-[4-(4-Fluoro-phenyl)-2-methyl-2H-pyrazol-3-yl]-1-{2-[5-(4-fluoro-phenyl)-tetrazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.03 g) was prepared from the compound of description 92 (0.09 g) and 4-(4-fluoro-phenyl)-2-methyl-2H-pyrazole-3-carboxylic acid (0.070 g) according to the method of Description 20.
Found 464 (MH+) C24H23F2N7O requires 463.
EXAMPLE 144
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-imidazol-1-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.065 g) was prepared from the compound of description 94 (0.07 g) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.069 g) according to the method of Description 20.
Found 461 (MH+) C26H25FN4OS requires 460.
EXAMPLE 145
(RS)-1-[5-(4-Fluoro-phenyl)-thiazol-4-yl]-1-[2-(4-phenyl-imidazol-1-ylmethyl)-piperidin-1-yl]-methanone
The title compound (010 g) was prepared from the compound of description 94 (0.07 g) and 5-(4-Fluoro-phenyl)-thiazole-4-carboxylic acid (0.065 g) according to the method of Description 20.
Found 447(MH+) C25H23FN4OS requires 446.
EXAMPLE 146
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1]-pyrazol-3-yl]-1-[2-(4-phenyl-imidazol -1-ylmethyl)-piperidin-1-yl]methanone
The title compound (0.135 g) was prepared from the compound of description 94 (0.07 g) and 4-(4-fluoro-phenyl)-1-methyl-1H-pyrazole-3-carboxylic acid (0.064 g) according to the method of Description 20.
Found 444 (MH+) C26H26FN5O requires 443.
EXAMPLE 147
(RS)-1-[5-(4-Fluoro-phenyl-2-methyl-thiazol-4-yl]-1-{2-[3-(4-fluoro-phenyl) -pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.10 g) was prepared from the compound of description 96 (0.086 g) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.075 g) according to the method of Description 20.
Found 479 (MH+) C26H24F2N4OS requires 478.
EXAMPLE 148
(RS)-1-(5-Bromo-2-methoxy-phenyl)-1-{2-[3-(4-fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.125 g) was prepared from the compound of description 96 (0.086 g) and 5-bromo-2-methoxybenzoic acid (0.08 g) according to the method of Description 20.
EXAMPLE 149
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.09 g) was prepared from the compound of description 96 (0.086 g) and 5-(4-fluoro-phenyl)-2-methyl-2H-[1,2,3]triazole-4-carboxylic acid (0.078 g) according to the method of Description 20.
Found (MH+) 463 C25H24F2N6O requires 462.
EXAMPLE 150
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-oxazol-4-yl]-1-{2-[3-(4-fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.11 g) was prepared from the compound of description 96 (0.086 g) and 5-(4-fluoro-phenyl)-2-methyl-oxazole-4-carboxylic acid (0.078 g) according to the method of Description 20.
Found 463 (MH+) C26H24F2N4O2 requires 462.
EXAMPLE 151
1-{2-[3-(4-Fluoro-phenyl)-pyrazol-1-ylmethyl]-piperidin-1-yl}-1-[2-(3-methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone
The title compound (0.05 g) was prepared from the compound of description 96 (0.086 g) and 2-(3-Methyl-[1,2,4]oxadiazol-5-yl)-benzoic acid (0.070 g) according to the method of Description 20.
Found 446 (MH+) C25H24FN5O2 requires 445.
EXAMPLE 152
(RS)-1-[5-(4-luoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-phenyl-thiazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.133 g) was prepared from the compound of description 99 (0.184 g) according to the method of description 20.
Found 478 (MH+) C26H24FN3OS2 requires 477.
EXAMPLE 153
(R)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-methanone and (S)-(R)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[3-(4-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-methanone
The title compounds were isolated by chiral HPLC on a Chiralcel OD; 250 mm×19 mm i.d.; 10 micron particle size column, with a mobile phase of n-Hexane, Ethanol (80:20 v/v) with a flow rate of 17 ml/min-1, a runtime of 20 min with detection by UV absorbance at 215 nM. The racemic compound of example 67 was injected in ethanol (2 ml) at 4 mg/ml. The two enantiomers were isolated as the faster and slower running components with ee's of 99.4% and 96.6%.
Faster running component Mass Spectrum (API+): Found 464 (MH+). C25H22FN3O3S requires 463.
Slower running component Mass Spectrum (API+): Found 464 (MH+). C25H22FN3O3S requires 463.
EXAMPLE 154
(RS)-1-{2-[5-(2,5-Dimethyl-2H-pyrazol-3-yl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4 yl]-methanone
The compound of description 101 (0.35 g) and polyphosphoric acid (0.70 g) were combined and warmed at 140° C. for 4 h. The reaction was cooled to room temperature, potassium carbonate and iced water added the basic solution was extracted with dichloromethane (×2), the combined organic phase washed with water, dried and solvent removed at reduced pressure. The residue was column chromatographed (silica gel; 20% ethyl acetate in pentane eluant) to give the title compound (0.073 g)
Mass Spectrum (API+): Found 481 (MH+). C24H25FN6O2S requires 480.
EXAMPLE 155
(RS)-1-[2-(4,5-Dipheny)-1H-imidazol-2-ylmethyl)-piperidia-1-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The title compound (0.34 g) was prepared from the compound of description 102 (0.53 g) according to the method of example 64.
Mass Spectrum (API+): Found 537 (MH+). C32H29FN4OS requires 536.
EXAMPLE 156
(RS)-1-{2-[4(4-Fluoro-phenyl)-1-methyl-1H-imidazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4 fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The compound of example 83 (0.25 g) was added to sodium hydride (60% in oil, 0.042 g) in dimethylformaide (5 ml) and stirred until gas evolution had ceased. Iodomethane 0.163 g) was added, stirring continued for 16 h, diluted carefully with water and extracted with ethyl acetate (×4). The combined organic phase was washed with water and brine, dried (MgSO4) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 50% ethyl acetate:pentane eluant) to give after combining appropriate fractions the title compound (0.06 g).
Mass Spectrum (API+): Found 493 (MH+). C27H26F2N4OS requires 492.
EXAMPLE 157
(RS)-1-[2-(5-Benzofuran-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(3-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The title compound (0.038 g) was prepared from the compound of description 104 and 5-(3-Fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.068 g) according to the method of description 20.
Mass Spectrum (API+): Found 503 (MH+). C27H23FN4O3S requires 502.
EXAMPLE 158
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(4-pyridin-2-yl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The compound of description 105 (0.56 g) and 2-bromo-1-pyridin-2-yl-ethanone (0.44 g) were combined in dichloromethane (2 ml). The mixture was heated to 100° C. until the dichloromethane had evaporated and then heating continued at 140° C. for 6 h. The reaction was cooled to room temperature, and the residue dissolved in sodium hydroxide/dichloromethane, the organic phase separated, dried, solvent removed at reduced pressure and the residue column chromatographed (silica gel; 0→8% methanol/dichloromethane) to give after combining the appropriate fractions the title compound (0.05 g)
Mass Spectrum (API+): Found 463 (MH+). C25H23FN4O2S requires 462.
EXAMPLE 161
(RS)-1-[5-(4-Fluorophenyl)-2-methylthiazol-4-yl]-1-{2-[5-(4-fluorophenyl)-1H]-pyrazol-3-ylmethyl]-piperidin-1-yl}-methanone
The compound of description 108 (0.430 g) was dissolved in ethanol (20 ml) and stirred at room temperature for 16 hours with hydrazine hydrate (0.087 ml). The solution was then evaporated at reduced pressure and chromatographed over silica gel, eluting with a gradient of 0 to 10% [9:1 methanol/conc. ammonia solution] in dichloromethane. The title compound was obtained as a white foam (0.034 g), mass spectrum (API+) 479 [MH+], (API−) 477 [(M-H)−] C26H24F2N4OS requires 478
EXAMPLE 162
(RS)-1-{2-[4(4-Fluorophenyl)-1H-imidazol-2-ylmethyl]-piperazin-1-yl}-[5-(4-fluorophenyl)-2-methylthiazol-4-yl]-methanone
3-[4-4-Fluorophenyl)-1H-imidazol-2-ylmethyl]-4-{-[5-(4-fluorophenyl)-2-methylthiazol-4-yl]-methanoyl}-piperazine-1-carboxylic acid tert-butyl ester description 112 (0.130 g) was dissolved in TFA and stirred under argon at room temperature for 3 hours. The TFA was evaporated and the residue chromatographed over silica gel, eluting with a gradient of 0 to 10% [9:1 methanol/conc. ammonia solution] in dichloromethane. The title compound was obtained as a white foam (0.095 g),
mass spectrum (API+) 480 [MH+], C25H23F2N5OS requires 479.
EXAMPLE 163
1-[5-(4-Fluorophenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(4-fluorophenyl)-oxazol -2-ylmethyl]-piperazin-1-yl}-methanone
4-{1-[5-(4-Fluorophenyl)-2-methyl-tliiazol-4-yl]-methanoyl}-3-[4-(4-fluoro-pbenyl)-oxazol-2-ylmethyl]-piperazine-1-carboxylic acid tert-butyl ester (0.130 g) was dissolved in trifluoroacetic acid (10 ml) and stirred at rdom temperature for 2 hours. The reaction mixture was then evaporated to dryness at reduced pressure and the residue was chromatographed over silica gel. Elution with a gradient of 0 to 10% [9:1 methanol/conc. ammonia solution] in dichloromethane provided the title compound as a pale yellow gum (0.013 g), mass spectrum (API+) 481 [MH+], C25H22F2N4O2S requires 480.
EXAMPLE 164
(RS)-1-[3-(5-bromo-4-phenyl-oxazol-2-ylmethyl)-morpholin-4-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The compound of example 67 (0.152 g) was dissolved in carbon tetrachloride (10 ml) and was then treated with N-bromosuccinimide (0.058 g) and stirred under argon at room temperature for 24 h. A further quantity of N-bromosuccinimide (0.006 g) was added and the mixture stirred for a further 1 h. The mixture was filtered through a cotton wool plug and the filtrate was evaporated to dryness under reduced pressure. The residue was column chromatographed (silica gel, 0→40% ethyl acetate-pentane) to give the title compound (0.117 g).
Mass Spectrum (API+ LC/MS): Found 542, 544. C25H21BrFN3O3S requires 541,543.
EXAMPLE 165
(RS)-1-[2-(5-Chloro-4-phenyl-oxazol-2-ylmiethyl)piperidin-1-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The oxazole of example 70 (0.06 g) in carbon tetrachloride (10 ml) was treated with N-chlorosuccinimide (0.018 g) and stirred at room temperature, under argon, for 6 h. A further quantity of N-chlorosuccinimide (0.009 g) was added and the mixture heated at 80° C., under argon for 16 h. The solvent was removed under reduced pressure. The residue was partitioned between ethyl acetate and water. The organic layer was dried (magnesium sulfate) and the solvent removed under reduced pressure. The residue was column chromatographed (silica gel; 0→40% ethyl acetate-pentane) to afford the title compound (0.024 g).
Mass Spectrum (Electrospray LC/MS); 496,498 (MH+). C26H23ClFN3O2S requires 495,497.
EXAMPLE 166
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(5-phenyl-4H-[1,2,4]triazol-3-ylmethyl)-pyrrolidin-1-yl]-methanone
The title compound (0.077 g) was prepared from the amine of description 117 (0.072 g) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.075 g) according to the method of example 1.
Mass Spectrum (API+ LC/MS): 448 (MH+). C24H22FN5OS requires 447.
EXAMPLE 167
(RS)-1-[2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The title compound (0.412 g) was prepared by treating the compound of example 70 with N-bromosuccinimide (0.190 g) according to the method of example 164.
Mass Spectrum (Electrospray LC/MS): 540, 542 (MH+). C26H23BrFN3O2S requires 539, 541.
EXAMPLE 168
(RS)-1-(2-Methyl-5-phenyl-thiazol-4-yl)-1-[2-(4-phenyl-oxazol-2-ylmethyl) -piperidin-1-yl]-methanone
The title compound (0.165 g) was prepared from the amine of description 77 (0.116 g) and 2-Methyl-5-phenyl-thiazole-4-carboxylic acid (0.105 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): 444 (MH+). C26H25N3O2S requires 443.
EXAMPLE 169
(RS)-1-[1-(2-Dimethylamino-ethyl)-4(4 fluoro-phenyl)-1H-pyrazol-3-yl]-1-[2(4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.169 g) was prepared from the amine of description 77 (0.116 g) and 1-(2-Dimethylamino-ethyl)-4-(4-fluoro-phenyl)-1H-pyrazole-3-carboxylic acid (0.132 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): 502 (MH+). C29H32FN5O2 requires 501.
EXAMPLE 170
(RS)-2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-ylmethyl)-4-phenyl-oxazole-5-carbonitrile
The title compound (50 mg) was prepared by treating the compound of example 167 (0.410 g) with copper(I)cyanide (0.103 g) according to the method of example 96. Following column chromatography, further purification by HPLC was required (Supercosil ABZ+, 5-95% acetonitrile containing 0.1% trifluoroacetic acid-water containing 0.1% trifluoroacetic acid).
Mass Spectrum (Electrospray LC/MS): 487 (MH+). C27H23FN4O2S requires 486.
EXAMPLE 171
(RS)-1-[2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-1-(2-methyl-5-phenyl-thiazol-4-yl)-methanone
The title compound (0.075 g) was prepared by treating the compound of example 168 (0.093 g) with N-bromosuccinimide (0.037 g) according to the method of example 164.
Mass Spectrum (Electrospray LC/MS): 522,524 (MH+). C26H24BrFN3O2S requires 521,523.
EXAMPLE 172
1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[(S)-2-(4-phenyl-oxazol-2-ylmethyl)-pyrrolidin-1-yl]-methanone
The title compound (0.103 g) was prepared from the amine of description 120 (0.061 g) and 5-(4-fluoro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.064 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): 448 (MH+). C25H22FN3O2S requires 447.
EXAMPLE 173
1-[(S)-2-(5-Bromo-4-phenyl-oxazol-2-ylmethyl)-pyrrolidin-1-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone
The title compound (0.066 g) was prepared by treating the compound of example 172 (0.075 g) with N-bromosuccinimide (0.030 g) according to the method of example 164.
Mass Spectrum (Electrospray LC/MS): 526,528 (MH+). C25H21BrFN3O2S requires 525,527.
EXAMPLE 174
(RS)-1-[5-(4-Chloro-phenyl)-2-methyl-thiazol-4-yl]-[2-(4-pbenyl-oxazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.106 g) was prepared from the amine of description 77 (0.072 g) and 5-(4-chloro-phenyl)-2-methyl-thiazole-4-carboxylic acid (0.076 g) according to the method of example 1.
Mass Spectrum (API+ LC/MS): 478,480 (MH+). C26H24ClN3O2S requires 477, 479.
EXAMPLE 175
(RS)-1-[4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazol-3-yl]-1-[2-(4-phenyl-thiazol-2-ylmethyl)-piperidin-1-yl]-methanone
The title compound (0.022 g) was prepared from the compound of description 99 (0.060 g) and 4-(4-Fluoro-phenyl)-1-methyl-1H-pyrazole-3-carboxylic acid (0.044 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): Found 461 (MH+). C26H25FN4OS requires 460.
EXAMPLE 176
(RS)-1-{2-[4(2-Bromo-phenyl)-oxazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4yl]-methanone
The title compound (0.50 g) was prepared from the compound of description 121 (2.00 g), acetamide (1.05 g) and boron trifluoride.diethyl etherate (0.7 ml) in xylene according to the method of example 54.
Mass Spectrum (Electrospray LC/MS): Found 540,542 (MH+). C26H23BrFN3O2S requires 539,541.
EXAMPLE 177
(RS)-2-[2-(1-{1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanoyl}-piperidin-2-ylmethyl)-oxazol-4-yl]-benzonitrile
A mixture of the bromide (0.240 g) of example 176, Cu(I)CN (0.060 g) and N-Methyl pyrrolidinone (5 ml) was heated at 180° C. for 16 h. The cooled reaction mixture was diluted with ethyl acetate and passed through kiesselguhr, washing with ethyl acetate. The filtrate was washed with water, dried (sodium sulfate) and solvent removed at reduced pressure. The residue was column chromatographed (silica gel, 20-50% ethyl acetate-pentane) to give the title compound as a pale yellow gum (0.101 g
Mass Spectrum (API+ LC/MS): Found 487 (MH+). C27H23FN4O2S requires 486.
EXAMPLE 178
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(2-fluoro-phenyl) -thiazol-2-ylmethyl]-piperidin-1-yl}-methanone
The title compound (0.235 g) was prepared as a solid from the amine of description 122 (0.330 g) and 2-methyl-5-(4-fluoro-phenyl)-thiazole-4-carboxylic acid (0.283 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): Found 496 (MH+). C26H23F2N3OS2 requires 495.
EXAMPLE 179
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-{2-[4-(3-fluoro-phenyl) -thiazol-2-ylmethyl]-pipendin-1-yl}-methanone
The title compound (0.047 g) was prepared as a solid from the amine of description 123 (0.100 g) and 2-methyl-5-(4-fluoro-phenyl)-thiazole-4-carboxylic acid (0.086 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): Found 496 (MH+). C26H23F2N3OS2 requires 495.
EXAMPLE 180
(RS)-1-{2-[4-(3-Fluoro-phenyl)-thiazol-2-ylmethyl]-piperidin-1-yl}-1-(2-methyl-5-phenyl-thiazol-4-yl)-methanone
The title compound (0.031 g) was prepared as a solid from the amine of description 123 (0.100 g) and 2-methyl-5-phenyl-thiazole-4-carboxylic acid (0.079 g) according to the method of example 1.
Mass Spectrum (Electrospray LC/MS): Found 478 (MH+). C26H24FN3OS2 requires 477.
It is understood that the present invention covers all combinations of particular and preferred groups described herein above.
Determination of Orexin-1 Receptor Antagonist Activity
The orexin-1 receptor antagonist activity of the compounds of formula (I) was determined in accordance with the following experimental method.
Experimental Method
CHO-DG44 cells expressing the human orexin-1 receptor were grown in cell medium (MEM medium with Earl's salts) containing 2 mM L-Glutamine, 0.4 mg/mL G418 Sulphate from GIBCO− BRL and 10% heat inactivated fetal calf serum from Gibco BRL. The cells were seeded at 20,000 cells/100 μl/well into 96-well black clear bottom sterile plates from Costar which had been pre-coated with 10 μg/well of poly-L-lysine from SIGMA. The seeded plates were incubated overnight at 37 C in 5% CO2.
Agonists were prepared as 1 mM stocks in water:DMSO (1:1). EC50 values (the concentration required to produce 50% maximal response) were estimated using 11× half log unit dilutions (Biomek 2000, Beckman) in Tyrode's buffer containing probenecid (10 mM HEPES with 145 mM NaCl, 10 mM glucose, 2.5 mM KCl, 1.5 mM CaCl2, 1.2 mM MgCl2 and 2.5 mM probenecid; pH7.4). Antagonists were prepared as 10 mM stocks in DMSO (100%). Antagonist IC50 values (the concentration of compound needed to inhibit 50% of the agonist response) were determined against 3.0 nM human orexin-A using 11× half log unit dilutions in Tyrode's buffer containing 10% DMSO and probenecid.
On the day of assay 50 μl of cell medium containing probenecid (Sigma) and Fluo3AM (Texas Fluorescence Laboratories) was added (Quadra, Tomtec) to each well to give final concentrations of 2.5 mM and 4 μM, respectively. The 96-well plates were incubated for 60 min at 37 C in 5% CO2. The loading solution containing dye was then aspirated and cells were washed with 4×150 μl Tyrode's buffer containing probenecid and 0.1% gelatin (Denley Cell Wash). The volume of buffer left in each well was 125 μl. Antagonist or buffer (25 μl) was added (Quadra) the cell plates gently shaken and incubated at 37 C in 5% CO2 for 30 minutes. Cell plates were then transferred to the Fluorescent Imaging Plate Reader (FLIPR, Molecular Devices) instrument. Prior to drug addition a single image of the cell plate was taken (signal test), to evaluate dye loading consistency. The run protocol used 60 images taken at 1 second intervals followed by a further 24 images at 5 second intervals. Agonists were added (by the FLIPR) after 20 seconds (during continuous reading). From each well, peak fluorescence was determined over the whole assay period and the mean of readings 1-19 inclusive was subtracted from this figure. The peak increase in fluorescence was plotted against compound concentration and iteratively curve fitted using a four parameter logistic fit (as described by Bowen and Jerman, TiPS, 1995, 16, 413-417) to generate a concentration effect value. Antagonist Kb values were calculated using the equation:

Kb=IC50/(1+([3/EC50])

where EC50 was the potency of human orexin-A determined in the assay (in nM terms) and IC50 is expressed in molar terms.
Compounds of Examples tested according to this method had pKb values in the range 6.7-9.5 at the human cloned orexin-1 receptor.
The orexin-2 receptor antagonist activity of the compounds of formula (I) was determined in accordance with the following experimental method.
Experimental Method
CHO-DG44 cells expressing the human orexin-2 receptor were grown in cell medium (MEM medium with Earl's salts) containing 2 mM L-Glutamine, 0.4 mg/mL G418 Sulphate from GIBCO BRL and 10% heat inactivated fetal calf serum from Gibco BRL. The cells were seeded at 20,000 cells/100 μl/well into 96-well black clear bottom sterile plates from Costar which had been pre-coated with 10 μg/well of poly-L-lysine from SIGMA. The seeded plates were incubated overnight at 37 C in 5% CO2.
Agonists were prepared as 1 mM stocks in water:DMSO (1:1). EC50 values (the concentration required to produce 50% maximal response) were estimated using 11× half log unit dilutions (Biomek 2000, Beckman) in Tyrode's buffer containing probenecid (10 mM HEPES with 145 mM NaCl, 10 mM glucose, 2.5 mM KCl, 1.5 mM CaCl2, 1.2 mM MgCl2 and 2.5 mM probenecid; pH7.4). Antagonists were prepared as 10 mM stocks in DMSO (100%). Antagonist IC50 values (the concentration of compound needed to inhibit 50% of the agonist response) were determined against 10.0 nM human orexin-A using 11× half log unit dilutions in Tyrode's buffer containing 10% DMSO and probenecid.
On the day of assay 50 μl of cell medium containing probenecid (Sigma) and Fluo3AM (Texas Fluorescence Laboratories) was added (Quadra, Tomtec) to each well to give final concentrations of 2.5 mM and 4 μM, respectively. The 96-well plates were incubated for 60 min at 37 C in 5% CO2. The loading solution containing dye was then aspirated and cells were washed with 4×150 μl Tyrode's buffer containing probenecid and 0.1% gelatin (Denley Cell Wash). The volume of buffer left in each well was 125 μl. Antagonist or buffer (25 μl) was added (Quadra) the cell plates gently shaken and incubated at 37 C in 5% CO2 for 30 minutes. Cell plates were then transferred to the Fluorescent Imaging Plate Reader (FLIPR, Molecular Devices) instrument. Prior to drug addition a single image of the cell plate was taken (signal test), to evaluate dye loading consistency. The run protocol used 60 images taken at 1 second intervals followed by a further 24 images at 5 second intervals. Agonists were added (by the FLIPR) after 20 seconds (during continuous reading). From each well, peak fluorescence was determined over the whole assay period and the mean of readings 1-19 inclusive was subtracted from this figure. The peak increase in fluorescence was plotted against compound concentration and iteratively curve fitted using a four parameter logistic fit (as described by Bowen and Jerman, TiPS, 1995, 16, 413-417) to generate a concentration effect value. Antagonist Kb values were calculated using the equation:

Kb=IC50/(1+([3/EC50])

where EC50 was the potency of human orexin-A determined in the assay (in nM terms) and IC50 is expressed in molar terms.
Compounds of Examples tested according to this method had pKb values in the range <6.3-8.2 at the human cloned orexin-2 receptor.
The application or which this description and claims forms part may be used as a basis for priority in respect of any subsequent application. The claims of such subsequent application may be directed to any feature or combination of features described herein. They may take the form of product, composition, process, or use claims and may include, by way of example and without limitation the following claims:

## Claims

1. A compound of formula (I):




wherein:
X is (CH2),
Y is CH2, CHOH, or —CH2CH(OH)—;
Het is an optionally substituted 1,3,4-oxadiazolyl substituted by R2, wherein R2 is an optionally substituted aryl;
Ar2 is an optionally substituted thiazolyl, pyrazolyl, thienyl, benzofuranyl, or triazolyl, wherein said thiazolyl, pyrazolyl, thienyl, benzofuranyl, or triazolyl is substituted by R1 and is further optionally substituted;
R1 is hydrogen, an optionally substituted (C1-4)alkoxy, halo, cyano, optionally substituted(C1-6)alkyl, or optionally substituted phenyl;
wherein said optionally substituted oxadiazolyl, aryl, thiazolyl, pyrazolyl, thienyl, benzofuranyl, triazolyl, (C1-4)alkoxy, (C1-6)alkyl, or phenyl is optionally substituted by halogen, hydroxy, oxo, cyano, nitro, (C1-4)alkyl, (C1-4)alkoxy, hydroxy(C1-4)alkyl, hydroxy(C1-4)alkoxy, halo(C1-4)alkyl, halo(C1-4)alkoxy, aryl(C1-4)alkoxy, (C1-4)alkylthio, hydroxy(C1-4)alkyl, (C1-4)alkoxy(C1-4)alkyl, (C3-6)cycloalkyl(C1-4)alkoxy, (C1-4)alkanoyl, (C1-4)alkoxycarbonyl, (C1-4)alkylsulfonyl, (C1-4)alkylsulfonyloxy, (C1-4)alkylsulfonyl(C1-4)alkyl, arylsulfonyl, arylsulfonyloxy, arylsulfonyl(C1-4)alkyl, (C1-4)alkylsulfonamido, (C1-4)alkylamido, (C1-4)alkylsulfonamido(C1-4)alkyl, (C1-4)alkylamido(C14)alkyl, arylsulfonamido, arylcarboxamido, arylsulfonamido(C1-4)alkyl, arylcarboxamido(C1-4)alkyl, aroyl, aroyl(C1-4)alkyl, aryl(C1-4)alkanoyl, (C1-4) acyl, aryl, aryl(C1-4)alkyl, (C1-4)alkylamino(C1-4)alkyl, RaRbN—, RaOCO(CH2)r, RaCON(Ra)(CH2)r, RaRbNCO(CH2)r, RaRbNSO2(CH2)r or RaSO2NRb(CH2)r, wherein r represents zero or an integer from 1 to 4, or RaRbN(CH2)n- or RaRbN(CH2)nO—, wherein n represents an integer from 1 to 4, wherein each of Ra and Rb independently represents a hydrogen atom or a (C1-4)alkyl group;
or a pharmaceutically acceptable salt thereof.

2. A compound according to claim 1 wherein R1 represents an optionally substituted phenyl group.

3. A compound according to claim 1 wherein Y is CH2.

4. A compound according to claim 1 wherein optional substituents for said optionally substituted (C1-4)alkoxy, (C1-6)alkyl or phenyl of R1 are halogen, (C1-4)alkoxy(C1-4)alkyl, RaRbN, RaRbN(CH2)n, RaRbN(CH2)nO, (C1-4)alkoxy, (C1-4)alkanoyl and (C1-4)alkyl.

5. A compound of formula (I) according to claim 1 selected from:
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-thiazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone;
(RS)-1-[5-(4-Fluoro-phenyl)-2-methyl-2H-[1,2,3]triazol-4-yl]-1-[2-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-methanone;
(RS)-1-{2-[5-(2,5-Dimethyl-2H-pyrazol-3-yl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone;
(RS)-1-[2-(5-Benzofuran-2-yl-[1,3,4]oxadiazol-2-ylmethyl)-piperidin-1-yl]-1-[5-(3-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone;
and a pharmaceutically acceptable salt thereof.

6. A compound according to claim 1, having the formula:




wherein Ar2 and R2 are selected from:














Ar2
R2




















 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 














 





















and a pharmaceutically acceptable salt thereof.

7. A pharmaceutical composition comprising the compound of formula (I), or the pharmaceutically acceptable salt thereof, according to claim 1, and a pharmaceutically acceptable carrier.

8. A compound which is (RS)-1-Dibenzofuran-4-yl-1-{2-[5-(3-fluoro-phenyl)-[1,3,4]oxadiazol-2-ylmethyl]-piperidin-1-yl}-methanone or a pharmaceutically acceptable salt thereof.

9. A pharmaceutical composition comprising the compound or the pharmaceutically acceptable salt thereof according to claim 8, and a pharmaceutically acceptable carrier.

10. A method of treating a disease or disorder where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of the compound, or the pharmaceutically acceptable salt thereof, according to claim 1, wherein said disease or disorder is selected from insomnia, parasomnia and jet-lag syndrome.

11. A method of treating a disease or disorder where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of the compound, or the pharmaceutically acceptable salt thereof, according to claim 8, wherein said disease or disorder is selected from insomnia, parasomnia and jet-lag syndrome.

12. A method according to claim 10, wherein said disease or disorder is insomnia.

13. A method according to claim 11, wherein said disease or disorder is insomnia.

14. A method of treating a disease or disorder where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of the compound, or the pharmaceutically acceptable salt thereof, according to claim 1, wherein said disease or disorder is selected from obesity and obesity associated with Type II diabetes.

15. A method of treating a disease or disorder where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of the compound, or the pharmaceutically acceptable salt thereof, according to claim 8, wherein said disease or disorder is selected from obesity and obesity associated with Type II diabetes.