3,9-DIAZABICYCLO (3.3.1) NONAN-7-YL DERIVATIVES, PROCESS AND INTERMEDIATES FOR THEIR PREPARATION AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM

Abstract: Compounds of formula (I) wherein X is a phenyl group or a monocyclic 5 or 6 membered heteroaryl group, either of which group is optionally fused to a saturated or unsaturated 5-7 membered carbocyclic or heterocyclic ring; A is linking moiety; Z is C1-6 alkyl, C3-8 cycloalkyl, C3-8 cycloalkyl C1-4 alkyl, phenyl, naphthyl, phenyl C1-4 alkyl or naphthyl C1-4 alkyl wherein a phenyl or naphthyl moiety is optionally substituted by one or more of halo, C1-6 alkoxy or C1-6 alkyl; R is hydrogen or methyl having 5-HT3 receptor antagonist activity.

Description: ,9-D1azab1cyclo (3.3.1) nonan-7-yl derivatives, process and intermediates for their preparation and pharmaceutical compositions containing them. This invention relates to novel compounds having pharmacological activity, to a process and intermediates for their preparation, and to their use as pharmaceuticals. EP-A-158265, EP-A-200444, EP-A-247266, EP-A-235878, EP-A-254584, EP-A-255297, EP-A-289170, EP-A-315390 and PCT/GB91/00636 (Beecham Group p.1.c. ) , EP-A-158532 (A.H. Robins Company, Inc.), EP-A-67770 (Merrell Toraude et Compagnie) , GB 2125398A and GB 2145416A (Sandoz Limited) , EP-A-322016 and EP-A-436245 (Duphar international Research B.V.), EP-A-307172 (Eli Lilly and Company), EP-A-323077, EP-A-306148, GB 2208385A and O91/05738 (John yeth and Brother Limited), EP-A-234872 (Adria Laboratories Inc.), EP-A-294292 (Adir et Compagnie), EP-A-339950 (Rorer International (overseas), Inc.), EP-A-309423 (Instituto de Angeli S.p.A.), EP-A-313393 and EP-A-407137 (Yoshitomi Pharmaceutical industries Limited) , EP-A-328200 and EP-A-337547 (Merck Sharp and Dohme Limited) , EP-A-329932 (Merrell Dow Pharmaceuticals Inc.), WO 90/06039 and WO 91/04738 (Rorer International (Overseas), Inc.), EP-A-378111 (Zambon Group S.p.A.), EP-A-430190 (Syntex (U.S .A. ) - Inc. ) and USA Patents 4920219 and 4920227 (Rorer Pharmaceutical Corp.) disclose classes of compounds which have a saturated azabicyclic moiety, such as tropanyl, granatyl or quinuclidinyl, and are 5-HT3 receptor antagonists. A class of novel compounds has now been discovered in which the saturated azabicyclic moiety is endo-3, 9- diazabicyclo[3.3.1]nonan-7-yl. These compounds have 5-HT 3 receptor antagonist activity. Accordingly, the present invention provides a compound of formula (I) , or a pharmaceutically acceptable salt thereof: wherein X is a phenyl group or a monocyclic 5 or 6 membered heteroaryl group, either of which group is optionally fused to a saturated or unsaturated 5-7 membered carbocyclic or heterocyclic ring; A is a linking moiety; Z is C^_g alkyl, C3_g cycloalkyl, C3_g cycloalkyl C^_ 4 alkyl, phenyl, naphthyl, phenyl C 1-4 alkyl or naphthyl alkyl wherein a phenyl or naphthyl moiety is optionally substituted by one or more of halo, C^_ alkoxy or C-^_ alkyl; R is hydrogen or methyl; having 5-HT receptor antagonist activity. X may be unsubstituted or substituted, usually by one or more substituents selected from halogen, C^_ alkoxy, C*__ Q alkylthio, C- j ^g alkyl, hydroxy, amino, C- j ^g alkylamino, C-^_η alkanoylamino, or two substituents on X (when fused) , may be linked to form a saturated or unsaturated optionally substituted carbocyclic ring. Heteroatoms for heteroaryl and heterocyclic groups within X are selected from oxygen, nitrogen and sulphur. Halo includes bromo, chloro and fluoro. X may be joined to A by an aromatic carbon atom, or (when X is fused) , by a carbocyclic ring carbon atom, or by a heterocyclic ring carbon or nitrogen atom. When X is fused, and A is attached at an aromatic carbon atom, it is preferably attached at the aromatic carbon adjacent -a ' fused' carbon atom, which is attached to the heteroatom of a heterocyclic ring in formula (I) . The azagranatane side chain may be attached to A in a 'spiro' configuration. X may also be further joined to A as defined in formula (IA) hereinafter, when Y-R^ Q is N-B=N. Suitable examples of X are as described in the aforementioned patent publications relating to 5-HT3 receptor antagonists, the subject matter of which is incorporated herein by reference. Suitable examples of A include CONH (amide) , COO (ester) , NHCONH (ureide) , CONHCONH (extended ureide) , or a group of structure (j) : ( j ) wherein the dotted circle represents two double bonds in any position in the 5 membered ring; two of G, H and I are selected from oxygen, sulphur, nitrogen and carbon and the other is oxygen, sulphur or nitrogen; and E is a bond or C^_c alkylene optionally substituted by phenyl or hydroxy; or E is absent and the heterocycle in structure (j) is joined to the azagranatane, in a 'spiro' configuration, when G is nitrogen, H is methylene and I is oxygen or sulphur. For the avoidance of doubt, the suitable X values in formula (I) which are described in the referenced patent publications, are that part of the structure remaining when the saturated azabicyclic moiety and A (where A is one of the suitable examples listed above) , are disregarded. Z is often benzyl, n- or iso-butyl, n- or iso-propyl- ethyl or methyl, preferably isopropyl or ethyl. R is preferably methyl. There is a group of compounds within formula (I) wherein Z is C 1 _ alkyl, phenyl or phenyl C 1-4 alkyl optionally substituted as defined in formula (I) . In a particular aspect, the present invention provides a compound of formula (IA) , or a pharmaceutically acceptable salt thereof: (IA) wherein Y is NH or 0 (or is joined to R^ as defined below) ; X-L is a group of formula (a) , (b) , (c) , (d) , (e) , (f) , or (g) or (h) : (a) (b) 10 15 (C) 25 wherein R a to R e and R q to R^ are selected from hydrogen, halogen or hydroxy; R-L is hydrogen and R 2 is hydrogen or C^_^ alkyl; or R-L and R 2 together are a bond; R3 to Rη are independently hydrogen or C-^. alkyl; and R 4 together with R 2 may be C 2 __- polymethylene or C _g polymethylene interrupted by an -0- linkage when R-, is hydrogen; Ro and R q are independently selected from hydrogen or C--_g alkyl or Rg and Rg together are C 2 _g polymethylene or C 2 _5 polymethylene interrupted by an -0- linkage; either R 1Q is hydrogen, C 1 _ alkoxy, C _g cycloalkyloxy or c 3-8 cycloalkyl C 1-4 alkyloxy; or R-^ Q is joined to Y so that Y-Rχo is N-B=N where B is N or CH; and R -- is hydrogen, halo, C--_g alkoxy or C-^g alkyl; or R-i Q and R-ι are joined to form -E- wherein E is (CH 2^n or NR i7 c ° (CH 2^ m w he re _- n n is 1 or 2 and m is 0 or 1 and R15, R j and R 17 are independently selected from hydrogen or C^_g alkyl; R 12 is hydrogen, C-^. alkoxy or; amino optionally substituted by a C^_g alkyl group, or R^ 2 is alkanoylamino; and R 13 is halo, C-__g alkyl, C-^. alkoxy or ^_g alkylthio; alkyl; in formula (h) : CO-Y- is in the 1-position and either R^ is in the 3-position and is hydrogen, C 1 _ alkyl or C^_g alkoxy, or is in the 4-position and is hydrogen, halogen, CF3, C-L_g alkyl, C 1-7 acyl, C 1-7 acylamino, phenyl optionally substituted by one or two C-^. alkyl, C^ alkoxy or halogen groups, or amino, aminocarbonyl or aminosulphonyl, optionally substituted by one or two C^_g alkyl or C3_g cycloalkyl groups or by C 4 _c- polymethylene or by phenyl, C^.g alkylsulphonyl, C _ alkylsulphinyl, C-^. alkoxy, C-^. alkylthio, hydroxy or nitro; or CO-Y- is in the 3-position and either R-^ is in the 1-position and is hydrogen, C-^. alkyl or C^_g alkoxy, or alkoxy; L is CH or N; and Z and R are as defined in formula (I) . Examples of moieties in alkyl or alkyl containing groups in Z or in R-_ to R 15 include methyl, ethyl, n- and iso-propyl, n-, iso-, sec- and tert-butyl, preferably methyl. Cycloalkyl moieties include C3, C 4 , C5, Cg, C 7 and Cg cycloalkyl. Halo moieties include fluoro, chloro, bromo and iodo. Suitable examples of R 2 and R 4 or Rg and Rg when joined include C 2 , C3, C 4 , C5 or Cg polymethylene, preferably C 2 , C3, C 4 or C5 polymethylene. R a to R e and R_ to R^ are preferably selected from hydrogen, fluoro, chloro and hydroxy, most preferably hydrogen. R^ may be 5-, 6- or 7-chloro or fluoro. When X is of sub-formula (a) , one of R- j _ and R3 is preferably hydrogen and one or both of R 2 and R 4 (most preferably both) are alkyl groups, such as methyl, or are joined to form C 2 _7 polymethylene; or when one of R 2 and R^ is hydrogen, the other is preferably ethyl or n- or iso- propyl. When X is of sub-formula (b) , Re is preferably hydrogen or a methyl or ' ethyl group. When X is of sub-formula (c) , one of CO-Y and Rg is attached at the 1-position and the other is attached at the 3-position as depicted in sub-formula (c) , and Rg is preferably methyl or ethyl. When X is of sub-formula (d) , R7 is preferably methyl. When X is of sub-formula (e) , Rg and Rg are preferably both methyl groups. When X is of sub-formula (f) , and R 1Q is C--_g alkoxy or is joined to Y, R 12 s preferably amino and R-^ is preferably chloro or bromo, most preferably chloro. R- ^Q is preferably methoxy when C---5 alkoxy. When X is of sub-formula (f) , and R 10 is hydrogen, Rg and R- are preferably chloro or methyl and R-<_Q is preferably hydrogen. Other values of X within sub-formula (f) of interest are those described in EP-A-307172 (Eli Lilly and Company) and EP-A-313393 (Yoshitomi Pharmaceutical Industries Limited) . When X is of sub-formula (g) , R-- 4 is preferably hydrogen or methyl. When X is of sub-formula (h) , and CO-Y- is in the 1-ρosition suitable examples of R-_^ when in the 4-position, include the following: hydrogen, chloro, bromo, methyl, ethyl, amino, methylamino, dimethylamino, phenyl, alkanoylamino such as formylamino, acetyla ino, propionylamino, n_- and iso-butyrylamino, aminosulphonyl, and amino and aminosulphonyl optionally substituted by one or two-methyl, ethyl, n- or iso-propyl, n-, sec-, iso- or tert-butyl or phenyl groups; nitro, n- and iso-propoxy, methylthio, ethylthio, n- and iso-propylthio, hydroxy, methylsulphonyl and ethylsulphonyl or when R- j ^ is in the 3-position suitable examples, include the following groups, hydrogen, methyl, ethyl, n- or iso-propyl, methoxy, and ethoxy. When X is at sub-formula (h) , and the CO-Y- is in the 3-position, suitable examples of R--^ when in the 1-position, include hydrogen, methyl, ethyl, n- or iso- propyl, or when is in the 4-position, suitable examples include the following: hydrogen, methoxy and ethoxy. Preferred groups, in any of the positions specified above, include hydrogen, methyl and methoxy. CO-Y- is preferably in the 1-position. Y is preferably NH. The pharmaceutically acceptable salts of the compounds of the formula (I) include acid addition salts with conventional acids such as hydrochloric, hydrobromic, boric, phosphoric, sulphuric acids and pharmaceutically acceptable organic acids such as acetic, tartaric, maleic, citric, succinic, benzoic, ascorbic, methanesulphonic, α-keto glutaric, α-glycerophosphoric, and glucose-1-phosphoric acids. The pharmaceutically acceptable salts of the compounds of the formula (I) are usually acid addition salts with acids such as hydrochloric, hydrobromic, phosphoric, sulphuric, citric, tartaric, lactic and acetic acid. Preferably the acid addition salt is the hydrochloride salt. Examples of pharmaceutically acceptable salts include quaternary derivatives of the compounds of formula (I) such as the compounds quaternised by compounds R χ -T wherein R χ is c l-6 a-lkyi- P her -yl~Cχ_g alkyl or C _ 7 cycloalkyl, and T is a radical corresponding to an anion of an acid. Suitable examples of R χ include methyl, ethyl and n- and iso-propyl; and benzyl and phenethyl. Suitable examples of T include halide such as chloride, bromide and iodide. Examples of pharmaceutically acceptable salts also include internal salts such as N-oxides. -li¬ lt will be appreciated that mono- or di- salts may be formed owing to the presence of two salifiable nitrogens in the azagranatane side chain. The compounds of the formula (I) , their pharmaceutically acceptable salts, (including quaternary derivatives and N-oxides) may also form pharmaceutically acceptable solvates, such as hydrates, which are included wherever a compound of formula (I) or a salt thereof is herein referred to. It will of course be realised that some of the compounds of the formula (I) have chiral or prochiral centres and thus are capable of existing in a number of stereoisomeric forms including enantiomers. The invention extends to each of these stereoisomeric forms (including enantiomers) , and to mixtures thereof (including racemates) . The different stereoisomeric forms may be separated one from the other by the usual methods. The invention also provides a process for the preparation of a compound of formula (I) which process comprises reacting a compound X'-A-- with a compound of formula (II) : (ID wherein A- j _ and A 2 are moieties which react together, usually by an amide or ester coupling, or by condensation to form a heterocycle (j) as hereinbefore defined, to form A as defined; X' is X or a group convertible thereto and R' and Z' are R and Z as defined or a hydrogenolysable protecting group; and thereafter as desired or necessary, converting X' to X, converting R'/Z', when other than R/Z, to R/Z,. and optionally forming a pharmaceutically acceptable salt of the compound of formula (I) . Suitable values of A-^ and A 2 are as described in the aforementioned patent publications. Intermediates of the formula X' -A^ are generally known from the aforementioned patent publications/references, or are prepared by analogous methods to those used for structurally related known compounds. Intermediates of the formula (II) are generally prepared from the compound of formula (III) : (III) which is prepared by the condensation/cyclisation of as appropriate 2, 6-disubstituted piperazine derivative, as described in the descriptions hereinafter. In a particular aspect, the invention also provides a process for the preparation of a compound of formula (IA) , or a pharmaceutically acceptable salt thereof, which process comprises reacting a compound of formula (IV) : X 1 ' -C0Q 1 (IV) with a compound of formula (V) : or a reactive derivative thereof, when Y is 0; wherein X--' is X-^ or a group convertible thereto; Q^ is a leaving group; R' is R as defined, or a hydrogenolysable protecting group; and the remaining variables are as hereinbefore defined; and thereafter optionally converting X-_' to X-., including any R a , R b , R c , R d , R e , R g , R h or R 1Q , R l l ' R 12' R 13' R 14 or R 15 9 rou P to another such group, converting R'/Z', when other than R/Z, to R/Z; and optionally forming a pharmaceutically acceptable salt of the resultant compound of formula (IA) . Examples of leaving groups Q-^, displaceable by a nucleophile, include halogen such as chloro and bromo, ^_^ alkoxy, such as CH3O and C2H5O-, PhO-, or activated hydrocarbyloxy, such as Cl^CgO- or CI3CO- If a group Q- j _ is a halide, then the reaction is preferably carried out at non-extreme temperatures in an inert non-hydroxylic solvent, such as benzene, dichloromethane, toluene, diethyl ether, tetrahydrofuran (THF) or dimethylformamide (DMF) . It is also preferably carried out in the presence of an acid acceptor, such as an organic base, in particular a tertiary amine, such as triethylamine, trimethylamine, pyridine or picoline, some of which can also function as the solvent. Alternatively, the acid acceptor can be inorganic, such as calcium carbonate, sodium carbonate or potassium carbonate. Temperatures of 0°-100°C, in particular 10-80°C are suitable. If a group Q^ is C 1-4 alkoxy, phenoxy or activated hydrocarbyloxy then the reaction is preferably carried out in an inert polar solvent, such as toluene ordimethylformamide. It is also preferred that the group Q-^ is CI3CO- and that the reaction is carried out in toluene at reflux temperature. When Y is 0 the compound of formula (V) may be in the form of a reactive derivative thereof, which is often a salt, such as the lithium, sodium or potassium salt. Usually, X-^' will be X-^, but when R-^ is joined to Y, in formula (IA) , X-^' is of sub-formula (f) wherein R-_Q is nitro or amino, which may be subsequently be linked to Y as described in EP-A-315390. It will be apparent that compounds of the formula (IA) containing an R a to R e , R-, R^ or R 1( - to R-^ group which is convertible to another such group are useful novel intermediates. i.e. a hydrogen substituent is convertible to a halogen substituent by halogenation using conventional halogenating agents; or a C 1-7 alkanoylamino substituent is convertible to amino by conventional hydrolysis. R'/Z' when other than R/Z may be a hydrogenolysable protecting group which is benzyl optionally substituted by one or two groups selected from halo, -__ 4 alkoxy and ^_ 4 alkyl. Such benzyl groups may, for example, be removed, when R a to R e , R g , R h , R^ to R 15 is not halogen, by conventional transition metal catalysed hydrogenolysis to give the corresponding compound wherein R'/Z' is hydrogen. A further process for the preparation of a compound of the formula (I) or a pharmaceutically acceptable salt thereof, therefore comprises N-alkylating a compound of formula (I) , wherein R/Z is hydrogen and optionally forming a pharmaceutically acceptable salt of the resulting compound of the formula (I) . In this further process of the invention 'N-alkylation' comprises the substitution of the azabicyclic N-atoms by a group R/Z as hereinbefore defined. This may be achieved by reaction with a compound RQ or ZQ3 wherein R and Z are as hereinbefore defined and Q3 is a leaving group. Suitable values for Q include groups displaced by nucleophiles such as Cl, Br, I, OSO2CH or OS0 2 CgH 4 pCH 3 . Favoured values for Q 3 include Cl, Br and I. The reaction may be carried out under conventional alkylation conditions for example in an inert solvent such as dimethylformamide in the presence of an acid acceptor such as potassium carbonate. Generally the reaction is carried out at non-extreme temperature such as at ambient or slightly above. Alternatively, 'N-alkylation' may be effected under conventional reductive alkylation conditions. Interconverting R or Z in the compound of the formula (V) before coupling with the compound of the formula (IV) is also possible. Such interconversions are effected conveniently under the above conditions. It is desirable to protect any amine function with a group readily removable by acidolysis such as a C 2 _ 7 alkanoyl group, before R/Z interconversion. It is often convenient in the preparation of such a compound of formula (V) to prepare the corresponding compound wherein the ethylene group is replaced by -CO-, or for R or Z is methyl, where the methyl group is replaced by alkoxycarbonyl. Such compounds may then be reduced using a strong reductant such as lithium aluminium hydride to the corresponding compound of formula (IV) . The compounds of formula (IV) are known or are preparable analogously to, or routinely from, known compounds. Compounds of the formula (V) wherein R' is R and Z' is Z as defined, are novel and form an aspect of the invention. Compounds of the formula (I) may also be prepared by the processes analogous to those described in the aforementioned European Patent Publications. It will be realised that in the compound of the formula (I) the -A- linkage has an endo orientation with respect to the ring of the bicyclic moiety to which it is attached. A mixture of endo and exo isomers of the compound of the formula (I) may be synthesised non-stereospecifically and the desired isomer separated conventionally therefrom e.g. by chromatography; or alternatively the endo isomer-may if desired by synthesised from the corresponding endo form of the compound of the formula (II) . Pharmaceutically acceptable salts of the compounds of this invention may be formed conventionally. The salts may be formed for example by reaction of the base compound of formula (I) with a pharmaceutically acceptable organic or inorganic acid. The compounds of the present invention are 5-HT3 receptor antagonists and it is thus believed may generally be used in the ' treatment or prophylaxis of pain, emesis, CNS disorders and gastrointestinal disorders. Pain includes migraine, cluster headache, trigeminal neuralgia and visceral pain; emesis includes, in particular, that of preventing vomiting and nausea associated with cancer therapy, post-operative emesis, and nausea associated with migraine. Examples of such cancer therapy include that using cytotoxic agents, such as platinum complexes including cisplatin, and also doxorubicin and cyclophosphamide, particularly cisplatin; and also radiation treatment. CNS disorders include anxiety, psychosis, cognitive disorders such as senile dementia and age associated memory impairment (AAMI) , and drug dependence. Gastrointestinal disorders include irritable bowel syndrome and diarrohea. 5-HT3 receptor antagonists may also be of potential use in the treatment of obesity and/or arrhythmia. Some of the compounds of the invention may also have gastric prokinetic activity, useful in the treatment of gastrointestinal disorders, for example when R--4 is C^_g alkyl. The invention also provides a pharmaceutical composition comprising a compound of formula (I) , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier. Such compositions are prepared by admixture and are usually adapted for oral or parenteral administration, and as such may be in the form of tablets, capsules, oral liquid preparations, powders, granules, lozenges, reconstitutable powders, injectable and infusable solutions or suspensions or suppositories. Orally administrable compositions are preferred, since they are more convenient for general use. Tablets and capsules for oral administration are usually presented in a unit dose, and contain conventional excipients such as binding agents, fillers, diluents, tabletting agents, lubricants, disintegrants, colourants, flavourings, and wetting agents. The tablets may be coated according to well known methods in the art, for example with an enteric coating. Suitable fillers for use include cellulose, mannitol, lactose and other similar agents. Suitable disintegrants include starch, polyvinylpolypyrrolidone and starch derivatives such as sodium starch glycollate. Suitable lubricants include, for example, magnesium stearate. Suitable pharmaceutically acceptable wetting agents include sodium lauryl sulphate. Oral liquid preparations may be in the form of, for example, aqueous or oily suspensions, solutions, emulsions, syrups, or elixirs, or may be presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, for example sorbitol, syrup, methyl cellulose, gelatin, hydroxyethylcellulose, carboxymethylcellulose, aluminium stearate gel or hydrogenated edible fats, emulsifying agents, for example lecithin, sorbitan monooleate, or acacia; non-aqueous vehicles (which may include edible oils) , for example, almond oil, fractionated coconut oil, oily esters such as esters of glycerine, propylene glycol, or ethyl alcohol; preservatives, for example methyl or propyl p-hydroxybenzoate or sorbic acid, and if desired conventional flavouring or colouring agents. Oral liquid preparations are usually in the form of aqueous or oily suspensions, solutions, emulsions, syrups, or elixirs or are presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, emulsifying agents, non-aqueous vehicles (which may include edible oils) , preservatives, and flavouring or colouring agents. The oral compositions may be prepared by conventional methods of blending, filling or tabletting. Repeated blending operations may be used to distribute the active agent throughout those compositions employing large quantities of fillers. Such operations are, of course, conventional in the art. For parenteral administration, fluid unit dose forms are prepared containing a compound of the present invention and a sterile vehicle. The compound, depending on the vehicle and the concentration, can be either suspended or dissolved. Parenteral solutions are normally prepared by dissolving the compound in a vehicle and filter sterilising before filling into a suitable vial or ampoule and sealing. Advantageously, adjuvants such as a local anaesthetic, preservatives and buffering agents are also dissolved in the vehicle. To enhance the stability, the composition can be frozen after filling into the vial and the water removed under vacuum. Parenteral suspensions are prepared in substantially the same manner except that the compound is suspended in the vehicle instead of being dissolved a d sterilised by exposure of ethylene oxide before suspending in the sterile vehicle. Advantageously, a surfactant or wetting agent is included in the composition to facilitate uniform distribution of the compound of the invention. The invention further provides a method of treatment or prophylaxis of pain, emesis, CNS disorders and/or gastrointestinal disorders in mammals, such as humans, which comprises the administration of an effective amount of a compound of the formula (I) or a pharmaceutically acceptable salt thereof. 5 An amount effective to treat the disorders hereinbefore described depends on the relative efficacies of the compounds of the invention, the nature and severity of the disorder being treated and the weight of the mammal. However, a unit dose for a 70kg adult will normally contain 10 0.05 to lOOOmg for example 0.5 to 500mg, of the compound of the invention. Unit doses may be administered once or more than once a day, for example, 2, 3 or 4 times a day, more usually 1 to 3 times a day, that is in the range of approximately 0.0001 to 50mg/kg/day, more usually 0.0002 to 15 25 mg/kg/day. No adverse toxicological effects are indicated at any of the aforementioned dosage ranges. 20 The invention also provides a pharmaceutical composition for use in the treatment and/or prophylaxis of pain, emesis, CNS disorders and/or gastrointestinal disorders which composition comprises an effect non-toxic amount of- a compound of formula (I) or a pharmaceutically acceptable 25 salt thereof and pharmaceutically acceptable carrier. The invention also provides a compound of formula (I) or a pharmaceutically acceptable salt thereof for use as an active therapeutic substance, in particular for use in the 30 treatment of pain, emesis, CNS disorders and/or gastrointestinal disorders. The following Examples illustrate the preparation of compounds of formula (I) ; the following descriptions 35 illustrate the preparation of intermediates. Intermediates of formulae (III) ' and (V) ' Dlc/d* CH 2 Ph D2c/d CH 2 Ph D3c/d Lp r D5c/d ^ • Bu D6c/d n Bu D7c/d Ph D8c/d Nm D9c/d Me DIOc/d Et Dllc/d Pe D12c/d Cm Nm = 1-naphthylmethyl; Cm = cyclohexylmethyl; Pe = phenethyl * mixture of endo and exo isomers Description 1 3-Benzyl-9-methyl-3, 9-diazabicyclo 13.3.11nonan-7-amine a) Ethyl 4-bromocrotonate (25g) in Et 2 0 (200 ml) -was stirred, cooled to 0°C and benzylamine (12.6ml) in Et2θ (50ml) was added dropwise. The reaction was stirred at room temperature for 2 days, filtered and the filtrate washed with H 2 0, dried (Na 2 S0 4 ) and concentrated. Column chromatography of the residue on silica, eluting with 1:3 Et 2 0:petrol gave diethyl-4, 4- L -benzylimino di-trans-2- butenoate (15g) . b) The above diester (29g) dissolved in MeOH (300ml) at 0°C was treated with solution of 33% MeNH 2 in IMS (5.7ml) . The reaction mixture was stirred at room temperature overnight, the solvent removed and the residue filtered through silica, eluting with 1:1 Et2θ:petrol to give dimethyl-4-benzyl-l-methyl-piperazinyl-2, 6-diacetate (Dlb) (13.9g) . c) The diester (13.9g) in toluene (150 ml) was added dropwise during lh to a stirred suspension of Bu OK- (12.9g) in toluene (600ml) being heated to reflux. After heating for a further 30 min., no starting material remained as determined by TLC. On cooling, the intermediate β-keto ester was extracted into 5N HCl (200ml) and the acidic extract heated to vigorous reflux for 5h. The reaction mixture was concentrated and the residue neutralised, then saturated with 2CO3 and the product extracted into CHCI3. The concentrated organic extracts were purified by column chromatography on silica, eluting with 5% MeOH/CHCl to give 3-benzyl-9-methyl-3, 9-diazabicyclo [3.3.1]nonan-7-one (Die) (3.7g) . d) The ketone (Die) (2g) in EtOH (50ml) was heated to reflux with H2 OH.HCI (0.65g) for lh. The reaction mixture was cooled, concentrated to approx. l/3rd volume, treated with a little ether and the hydrochloride salt of the oxime collected and dried (1.7g). The oxime hydrochloride (0.9g) was reduced with sodium (1.2g) in amyl alcohol (50ml) at reflux. After all the sodium had dissolved, the mixture was cooled to 90°C, water (4ml) was carefully added, then allowed to re-cool to room temperature. The aqueous layer was separated and the amyl alcohol extracted with an excess of 5N HCl. Concentration of the acidic extract, neutralisation then saturation with K2CO3 and extraction of the product into CHCI3 gave, on concentration, the title compounds (Did) (0.64g) as a crude mixture of endo and exo isomers. Description 2 endo-3-Benzyl-9-methyl-3, 9-diazabicycloT3.3.llnonan-7-amine a) To methyl-4-bromocrotonate (50g) in diethyl ether (500ml) was added, dropwise benzylamine (22ml) in diethyl ether (20ml) at 0°C. The reaction mixture was stirred at room temperature for 72h. The precipitate was removed by filtration and the filtrate washed with water (75 ml) . The organic phase was dried (MgS0 4 ) , the solvent evaporated under reduced pressure and the residue purified using flash chromatography on silica eluting with light petrol and diethyl ether to afford dimethyl-4,4 1 -benzyliminodi-trans-2- butenoate (17.lg). b) To dimethyl-4,4 1 -benzyliminodi—trans-2-butenoate (17.lg) in methanol (250 ml) was added dropwise methylamine (7.5 ml, 33% w/w in IMS) at 0°C. The reaction mixture was stirred overnight at room temperature. The solvent was evaporated under reduced pressure and the residue chromatographed on silica using light petrol and diethyl ether as the eluant to afford dimethyl-l-benzyl-4-methyl piperazinyl-3,5-diacetate as a mixture of cis and trans isomers (9.29g) . c) To potassium tert-butoxide (9.67g) in toluene (350 ml) was added dimethyl-4-benzyl-l-methyl piperazinyl-2, 6- diacetate (9.2βg) in toluene (150 ml) at room temperature under a nitrogen atmosphere. The reaction mixture was heated to reflux for 3h. The reaction mixture was cooled and washed with 5N HCl (4x75ml) . The combined aqueous extracts were heated to reflux for 13h. The reaction mixture was cooled, the solvent concentrated under reduced pressure and the residue saturated with solid potassium carbonate. The product was extracted into chloroform (4x75ml) , the organic phase dried (MgS0 4 ) and the solvent evaporated under reduced pressure. Flash chromatography on silica using chloroform with increasing volumes of ethanol (up to 10%) eluant gave 3-benzyl-9-methyl-3,9- diazabicyclo[3.3.1]nonan-7-one (D2c) (1.8g). d) To a stirred solution of the above ketone (1.80g) in ethanol (50ml) was added hydroxylamine hydrochloride (0.54g) . The reaction mixture was then heated to reflux for 2h. The reaction mixture was cooled and the solvent evaporated under reduced pressure. The residue was triturated with diethyl ether to give 3-benzyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-one oxime hydrochloride (1.87g). To a stirred solution of alane [generated by the action of cone. H2SO4 (0.93ml) on lithium aluminium hydride (0.88g) in dry THF (30ml)] was added 3-benzyl-9-methyl-3, 9- diazabicyclo[3.3.l]nonan-7-one oxime [generated by the treatment of 3-benzyl-9-methyl-3,9-diazabicyclo[3.3.1]nonan- 7-one oxime hydrochloride with potassium carbonate) . The reaction mixture was then heated to reflux overnight under a nitrogen atmosphere. The reaction mixture was cooled and 40% aqueous NaOH solution (2ml) and water (1ml) were added dropwise. Diethyl ether (5ml) was added and the mixture stirred for lh. The resultant precipitate was removed by filtration through keiselguhr and the filtrate concentrated under reduced pressure to afford the crude title compound (D2d) (0.90g) . Following the procedures outlined in Descriptions 1 and 2, parts a) to c) the following intermediates were obtained: 3-isopropyl-9-methyl-3, 9-diazabicyclo [3.3.1]nonan-7-one (D3c) ; 3-n-propyl-9-methyl-3, 9-diazabicyclo[3.3.1]nonan-7-one (D4c) ; 3-isobutyl-9-methyl-3, 9-diazabicyclo [3.3.1]nonan-7-one (D5c) ; 3- n butyl-9-methyl-3, 9-diazabicyclo[3.3.l]nonan-7-one (D6c) ; 9-methyl-3-phenyl-3, 9-diazabicyclo[3.3.1]nonan-7-one (D7c) ; 9-methyl-3- (1-naρhthylmethyl) -3, 9-diazabicyclo [3.3.l]nonan- 7-one (D8c) ; 3, 9-dimethyl-3, 9-diazabicyclo[3.3. l]nonan-7-one (D9c) ; 3-ethyl-9-methyl-3, 9-diazabicyclo [3.3.l]nonan-7-one (DIOc) ; 9-methyl-3- (2-phenethyl) -3, 9-diazabicyclo[3.3.1]nonan-7-one (Dllc); 3-cyclohexylmethyl-9-methyl-3, 9-diazabicyclo[3.3. l]nonan-7- one (D12c) . Following the procedures outlined in descriptions Id) and 2d) the following intermediates were obtained: endo-3-isopropyl-9-methyl-3, 9-diazabicyclo [3.3.l]nonan-7- amine (D3d) ; endo-3- n propyl-9-methyl-3, 9-diazabicyclo[3.3.1]nonan-7-amine (D4d) ; endo-3-isobutyl-9-methyl-3, 9-diazabicyclo[3.3.l]nonan-7- amine (D5d) ; endo-3- n butyl-9-methyl-3, 9-diazabicyclo [3.3.1]nonan-7-amine (D6d) ; endo-9-methyl-3-phenyl-3, 9-diazabicyclo[3.3.1]nonan-7-amine (D7d) ; endo-9-methy1-3- (1-naphthylmethyl) -3, 9-diazabicyclo[3.3.1]- nonan-7-amine (D8d) ; exo/endo-3, 9-dimethyl-3, 9-diazabicyclo[3.3.1]nonan-7-amine (D9d) ; endo-3-ethyl- -methy1-3, 9-diazabicyclo[3.3.l]nonan-7-amine (DIOd) ; endo-9-methyl-3- (2-phenethyl) -3, 9-diazabicyclo[3.3.1]- nonan-7-amine (Dlld) ; endo-3-cyclohexylmethyl-9-methyl-3, 9-diazabicyclo [3.3.1]- nonan-7-amine (D12d) ; Examples Ela/ CH 2 Ph Elb E2 Me E3 CH 2 Ph E4 ' • Pr E6 L Bu E8 Ph x l E9 (as E3) Nm E10 (as E3) Et Ell (as E3) Pe E12 (as E3) Cm E13 X χ = (a) CH 2 Ph R-_ = H, R 2 = Me, R 3 = H, R 4 = Me, R a = H. E14 (as E13) Lp r E15 (as E13) Me E16 (as E13) Et E19 (as E13) L Bu E20 (as E13) Cm E21 (as E13) H Example 1 endo-4-Acetylamino-5-chloro-2-methoxy-N- (3-benzyl-9-methyl- 3, -diazabicyclo [3.3.11nonan-7-yl)benzamide (Ela) A solution of the crude amine (Did) (0.64g) and Et (0.4ml) in CH 2 C1 2 (20ml) was added to a stirred solution of 4- acetylamino-5-chloro-2-methoxybenzoyl chloride (0.75g) in CH 2 C1 (50ml) at 0°C. After stirring overnight the reaction mixture was washed with aqueous aHCU3, dried, filtered and concentrated. The residue was purified by column chromatography on alumina, eluting with 1:1 CHCl :petrol to give three fractions; Fraction 1; 0.24g exo isomer Fraction 2; 0.46g mixture of endo/exo isomers Fraction 3; 0.23g endo isomer (mainly) compound El. endo-4-Amino-5-chloro-2-methoxy-N- (3-benzyl-9-methyl-3, 9- diazabicyclo T3.3.1]nonan-7-yl)benzamide (Elb) The mainly endo isomer (Ela), (fraction 3) (0.23g) was hydrolysed with 10% NaOH solution (1.0ml) in EtOH (20ml) and H 2 0 (5ml) heated for 2 hours. The solvent was removed and the residue extracted into CHCI . The organic extract was dried and concentrated. The residue was filtered through alumina, eluting with CHCI3 to give the desired product E2 (0.12g) mp 145-162°C which contained ca. 20% of the exo isomer. MS M + 428, 430 1 H NMR (CDCI3); δ: 9.8 (brd IH) , 8.15 (s, 0.2H), 7.7 (s, 0.8H), 7. 5-6.8 (m, 5H) , 6.29 (s, 0.2H), 6.21 (s, 0.8H) , 5.7-5.5 (m, 0.2H), 4.65-4.5 (m, 0.8H),4.35 (brs, 0.4H), 4.24 (brs, 1.6H), .86 (s, 0.6H), 3.78 (s 2.4H), 3.5 (s, 2H) , 3.0- 2.3 (m 9H including 2.5, s, 3H) , 1.42 (3, 1.6H) . Example 2 endo-4-Amino-5-chloro-2-methoxy-N- (3, 9-dimethyl-3, 9- diazabicyclo- [3.3.1]nonan-7-yl)benzamide (E2) The title compound was prepared in a similar manner to that described in Example 1, from 3, -dimethyl-3, 9- diazabicyclo [3.3.1]nonan-7-amine (D9d) . Example 3 endo-N-l-Methyl-3-indazolyl- (3-benzyl-9-methyl-3, 9- diazabicyclo [3.3.l]nonan-7-yl) carboxamide (E3) To a stirred suspension of l-methyl-lH-indazole-3-carboxylic acid (0.50g) in CH 2 C1 2 (40ml) was added oxalyl chloride (0.25ml) and 3 drops of DMF. The reaction mixture was stirred at room temperature for 2h. The solvent was evaporated under reduced pressure to afford crude 1-methyl- lH-indazole-3-carbonyl chloride. To a solution of l-methyl-lH-indazole-3-carbonyl chloride (127 mg) in CH2CI2 (20ml) was added a solution of endo-3- benzyl-9-methyl-3, 9-diazabicyclo [3.3.1]nonan-7-amine (D2d) (160 mg) and triethylamine (90μl) in CH 2 C1 2 (5ml) . The reaction mixture was stirred overnight at room temperature. The resulting solution was washed with saturated aHC03 solution, dried (MgS0 4 ) and the solvent removed under reduced pressure to afford crude product. Flash chromatography on silica using chloroform and ethanol as the eluant gave the title compound (E3) (33mg) mp 173-176°. λ E NMR (CD3OD) 400 MHz; δ: 1.51 (d, 2H) , 2.48 (s, 3H) , 2.51- 2.60 (m, 2H) , 2.63 (dd, 2H) , 2.80 (d, 2H) , 2.87-2.92 (m. 2H) , 3.92 (s, 5H) , 4.50-4.59 (m, IH) , 7.09-7.18 (m, 3H) , 7.29 (t, IH) , 7.35 (d, 2H) , 7.47 (t, IH) , 7.57 (d, 2H) , 8.22 (d, IH) . 5 M + 403 Examples 4-12 10 Following the general procedure outlined in Example 3, the following compounds were obtained: endo-N-l-Methyl-3-indazolyl- (3-isopropyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-yl)carboxamide (E4) 15 mp 180-184°C X H NMR (CDCI3) 250 MHz; δ: 1.27 (d, 6H) , 1.49 (d, 2H) , 2.45- 2.59 (m, 5H) , 2.65-2.81 (m, 3H) , 2.85 (d, 2H) , 4.08 (s, 3H) , 204.63-4.77 (m, IH) , 7.22-7.30 (m, IH) , 7.36-7.47 (m, 2H) , 8.42 (d, IH) , 10.62 (d, IH) . M + 355 5 endo-N-l-Methyl-3-indazolyl- (9-methyl-3- n propyl-3, 9- diazabicyclo[3.3.llnonan-7-yl) carboxamide (E5) mp 147-149°C 0 1 H NMR (CDCI3) 250MHz; δ: 0.97 (t, 3H) , 1.50 (d, 2H) , 1.70- 1.88 (m, 2H) , 2.43-2.63 ( , 2H) , 2.81-2.96 (m, 4H) , 4.07 (s, 3H) , 4.63-4.77 (m, IH) , 7.23-7.31 (m, IH) , 7.35-7.48 (m, 2H) , 8.41 (d, IH) , 10.70 (d, IH) . 5 W 355 endo-N-l-Methyl-3-indazolyl- (3-isobutyl-9-methyl-3 , 9- diazabicyclo [3.3.1] nonan-7-yl) carboxamide (E6) mp 107-109°C 1 H NMR (CDC1 3 ) 250 MHz; δ:0.89 (d, 6H) - 1.58 (d, 2H) , 1.95- 2.10 (m, IH) , 2.40-2.74 (m, 9H) , 2.87 (d, 2H) , 2.92-3.05 (m, 2H) , 4.09 (s, 3H) , 4.68-4.81 (m, IH) , 7.23-7.31 (m, IH) , 7.38-7.48 (m, 2H) , 8.34 (d, IH) , 10.25 (d, IH) . MH + 370 endo-N-l-Methyl-3-indazolyl- (3- n butyl-9-methyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide (E7) mp 91-93°C 1 H NMR (CDCI3) 250 MHz; δ: 0.93 (t, 3H) , 1.30-1.44 (m, 2H) , 1.52 (d, 2H) , 1.62-1.78 (m, 2H) , 2.47-2.68 (m, 9H) , 2.88 (d, 2H) , 2.91-2.99 (m, 2H) , 4.06 (s, 3H) , 4.65-4.78 (m, IH) , 7.22-7.30 (m, IH) , 35-7.47 (m, 2H) , 8.41 (d, IH) , 10.67 (d, IH) . MH + 370 endo-N-l-Methyl-3-indazolyl-(9-methyl-3-phenyl-3, 9- diazabicyclo [3.3.11nonan-7-yl) carboxamide (E8) mp 131-134°C λ R NMR (CDCI3) 250Hz; δ: 1.69 (d, 2H) , 2.61 (s, 3H) , 3.11- 3.21 (m, 2H) , 3.23-3.34 (m, 2H) , 3.39 (s, 3H) , 3.43-3.60 (m, 4H) , 4.69-4.72 (m, IH) , 6.98 (t, IH) , 7.08 (d, 2H) , 7.15- 7.41 (m, 5H) , 8.31 (d, IH) , 9.45 (d, IH) . M + 389 endo-N-l-Methyl-3-indazolyl- (3- (1-naphthylmethyl) -9-methyl- 3, 9-diazabicyclo f3.3.11nonan-7-yl) carboxamide (E9) MP 89-92°C X H NMR (CDCI3) 250 MHz; δ: 1.55 (d, 2H) , 2.44-2.61 (m, 5H) , 2.71-2.82 (m, 2H) , 2.83-3.00 (m, 4H) , 3.68 (s, 3H) , 4.45 (s, 2H) , 4.68-4.79 (m, IH) , 7.17 (t, IH) , 7.24-7.53 (m, 5H) , 7.64 (d, IH) , 7.71 (d, IH) , 7.82-7.91 (m, IH) , 8.20-8.28 (m, IH) , 8.43 (d, IH) , 10.87 (d, IH) . MH " * " 454 endo-N-l-Methyl-3-indazolyl- (3-ethyl-9-methyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide (E10) mp 140-143°C 1 H NMR (CDCI3) 250 MHz; δ: 1.30 (t, 3H) , 1.52 (d, 2H) , 2.45- 2.70 (m, 9H) , 2.85 (d, 2H) , 2.95 (brs, 2H) , 4.08 (s, 3H) , 4.60-4.75 (m, H) , 7.20-7.30 (m, H) , 7.35-7.46 (m, 2H) , 8.42 (d, H) , 10.85 (d, H) . MS M + = 341 endo-N-l-Methyl-3-indazolyl- (9-methyl-3-phenethyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide (Ell) mp 129-131° 1 H NMR (CDCI3) 250 MHz; δ: 1.57 (d, 2H) , 2.50-2.68 (m, 5H) , 2.70-2.84 (m, 2H) , 2.85-3.05 (m, 6H) , 3.06-3.18 (m, 2H) , 3.80 (s, 3H) , 4.68-4.80 (m, H) , 7.15-7.48 (m, 8H) , 8.40 (d, H) , 10.56 (d, H) . MS M + = 417 endo-N-1-Methyl-3-indazolyl- (3-cyclohexylmethyl-9-methyl- 3- 9-diazabicyclo 3.3.11nonan-7-y1) carboxamide (E12) mp 82-85°C λ H NMR (CDC1 3 ) 250 MHz; δ: 0.75-1.15 (m, 4H) , 1.40-1.72 (m, 8H) , 2.45 (d, 2H) , 2.48-2.72 (m, 7H) , 2.80 (d, 2H) , 2.94 (brs, 2H) , 4.10 (s, 3H) , 4.62-4.79 (m, H) , 7.20-7.32 (m, 2H) , 7.35-7.48 (m, 2H) , 8.32 (d, H) , 10.21 (d, H) . MS (El) M + = 409 Example 13 endo-N-3, 3-Dimethylindolin-l-yl (3-benzyl-9-methyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide (E13) A solution of 3, 3-dimethylindoline (1.5g) and triethylamine (1.42ml) in CH 2 C1 2 (15ml) was added dropwise to a cooled stirred solution of phosgene (9ml, 12.5% w/w in toluene) in CH2CI2 (15ml) . The reaction mixture was stirred for lh at 0°C and then poured into pentane (100ml) , washed with 5N sulphuric acid (5ml) and brine (5ml) . The organic phase was dried (MgS0 4 ) and the solvent evaporated under reduced pressure to give crude 1- (2, 3-dihydro-3, 3- dimethyl) indolylcarbonyl chloride (1.7g) . To a stirred solution of 1- (2, 3-dihydro-3, 3- dimethyl) indolylcarbonyl chloride (771mg) in CH 2 C1 2 (15ml) at ambient temperature was added endo-3-benzyl-9-methyl-3,9- diazabicyclo[3.3. l]nonan-7-amine (D2d) (902mg) and triethylamine (512μl) in CH 2 C1 2 (15ml) . The reaction mixture was stirred at room temperature overnight. The resulting solution was washed with aqueous aHC03 solution, dried (MgS0 4 ) and the solvent removed by rotary evaporation. Flash chromatography on silica using chloroform and ethanol as the eluant gave the title compound (E13) (360mg) mp 188- 191°C. ! H NMR (CDC1 3 ) 250MHz; δ: 1.29 (s, 6H) , 1.48 (d, 2H) , 2.40- 2.57 (m, 5H) , 2.62-2.78 (m, 4H) , 2.83-2.90 (m, 2H) , 3.53 (s, 2H) , 3.70 (s, 2H) , 4.39-4.42 (m, IH) , 6.90 (t, IH) , 7.05- 7.46 ( , 8H) , 7.81 (d, IH) , 8.78 (d, IH) . Examples 14-20 Following the general procedure outlined in Example 13, the following compounds were obtained; in the case of hydrochloride salts, by treatment of the free base with ethereal HCl. endo-N-3, 3-Dimethylindolin-l-yl (3-isopropyl-9-methyl-3, 9- diazabicyclo [3.3. l]nonan-7-yl) carboxamide (E14) mp 109-111°C 1 H NMR (CDC1 3 ) 250MHz; δ: 1.05 (d, 6H) , 1.33 (s, 6H) , 1.47 (d, 2H) , 2.41-2.75 (m, 10H) , 2.88-2.96 (m, 2H) , 3.65 (s, 2H) , 4.24-4.38 (m, IH) , 6.90 (t, IH) , 7.06-7.19 (m, 2H) , 7.80 (d, IH) , 8.58 (d, IH) . MH + 371 endo-N-3, 3-Dimethylindolin-l-yl (3, 9-dimethyl-3, 9-diaza- bicvclo [3.3.1]nonan-7-yl) carboxamide (E15) mp 173-175° 1 H NMR (CDCI3) 400 MHz; δ: 1.34 (s, 6H) , 1.45 (d, 2H) , 2.31 (s, 3H) , 2.40-2.50 (m, 2H) , 2.52 (s, 3H) , 2.55-2.65 (m, 2H) , 2.69 (d, 2H) , 2.88 (brs, 2H) , 3.54 (s, 2H) , 4.25-4.36 (m. H) , 6.90 (t, H) , 7.07 (d, H) , 7.15 (t, H) , 7.93 (d, H) , 9.15 (d, H) . MS M + =342 endo-N-3, 3-Dimethylindolin-l-yl (3-ethyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-yl) carboxamide (E16) mp 150° 1 R NMR (CDC1 3 ) 250 MHz; δ: 1.05 (t, 3H) , 1.35 (s, 6H) , 1.46 (d, 2H) , 2.40-2.60 (m, 9H) , 2.75 (d, 2H) , 2.90 (brs, 2H) , 3.60 (s, 2H) , 4.25-4.40 (m, H) , 6.90 (t, H) , 7.05-7.20 (m, 2H) , 7.85 (d, H) , 8.95 (d, H) . MS MH + = 357 endo-N-3, 3-Dimethylindolin-l-yl (3- n propyl-9-methyl-3- 9- diazabicyclo[3.3.1]nonan-7-yl)carboxamide hydrochloride (E17) mp 139-142°C ^-HNMR (CDCI3) 250 MHz - Free base; δ: 0.80 (t, 3H) , 1.32 (s, 6H) , 1.45 (d, 2H) , 1.62-1.79 ( , 2H) , 2.26-2.46 (m, 2H) , 2.47-2.57 (m, 7H) , 2.74 (d, 2H) , 2.82-2.89 (m, 2H) , 3.58 (s, 2H) , 4.21-4.33 (m, IH) , 6.89 (t, IH) , 7.01-7.19 (m, 2H) , 7.89 (d, IH) , 9.02 (d, IH) . MH+ 371 (Free base) endo-N-3, 3-Dimethylindolin-l-yl (3- n butyl-9-methyl-3, 9- diazabicyclo [3.3.11nonan-7-yl) carboxamide hydrochloride (E18) mp 135-138°C 1 H NMR (CDC1 3 ) 250 MHz - Free base; δ: 0.85 (t, 3H) , 1.15- 1.52 (m, 12H) , 2.30-2.56 (m, 9H) , 2.76 (d, 2H) , 2.83-2.92 (m, 2H) , 3.59 (s, 2H) , 4.23-4.37 (m, IH) , 6.60 (t, IH) , 7.06-7.20 (m, 2H) , 7.80 (d, IH) , 9.00 (d, IH) . MH + 385 (Free base) endo-N-3, 3-Dimethylindolin-l-yl (3-isobutyl-9-methyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide hydrochloride (E19) mp 141-144°C 1 H NMR (CDCI3) 250MHz (Free base); δ: 0.69 (d, 6H) , 1.30 (s, 6H) , 1.49 (d, 2H) , 2.17 (d, 2H) , 2.39-2.55 (m, 8H) , 2.65- 2.78 (m, 2H) , 2.81-2.90 (m, 2H) , 3.64 (s, 2H) , 4.25-4.37 (m, IH) , 6.88 (t, IH) , 6.98-7.15 (d, IH) , 7.51 (d, lH),- 8.69 (d, IH) . MH + 385 (Free base) endo-N-3 , 3-Dimethylindolin-l-yl (3-cyclohexylmethyl-9-methyl- 3 , 9-diazabicyclo [ 3 . 3 . l ] nonan-7-yl carboxamide hydrochloride (E20 ) mp 130°C X H NMR (CDCI3) 250 MHz; δ: 0.55-0.80 (m, 2H) , 0.85-1.38 ( , 8H, including 1.33 (s, 6H) . 1.40-1.90 (m, 10H) , 2.22 (d, 2H) , 2.40-2.59 (m, 7H including 2.50 (s, 3H) ) , 2.74 (d, 2H) , 2.85 ' (brs, 2H) , 3.65 (s, 2H) , 4.29-4.43 (m, H) , 6.90 (t, H) , 7.05-7.19 (m, 2H) , 7.62 (d, H) . MS M + = 425 Example 21 endo-N-3, 3-Dimethylindolin-l-yl- (9-methyl-3, 9- diazabicyclo [3.3.1]nonan-7-yl) carboxamide (E21) endo-N-3, 3-Dimethylindolin-l-yl (3-benzyl-9-methyl-3, 9- diazabicyclo[3.3.l]nonan-7-yl) carboxamide (E13) (350 mg) was hydrogenated at atmospheric pressure in methanol (50ml) over 5% Pd/C catalyst for 4h. The catalyst was removed by filtration and the filtrate evaporated to give the title compound (E21) (149mg) . mp 248-251°C 1 H NMR (CDC1 3 ) 250 MHz; δ: 1.35 (s, 6H) , 1.68 (d, 2H) , 2.50- 2.67 (m, 3H) , 2.75 (s, 3H) , 2.99 (d, 2H) , 3.17-3.26 (m, 2H) , 3.58 (s, 2H) , 3.61-3.71 (m, 2H) , 4.37-4.49 (m, IH) , 6.89- 6.97 (m, IH) , 7.06-7.20 (m, 2H) , 7.88 (m, IH) . M + 329 5-HT3 Receptor Antagonist Activity Compounds are evaluated for antagonism of the von Bezold-Jarisch reflex evoked by 5-HT in the anaesthetised rat according to the following method: Male rats 250-350g, are anaesthetised with urethane (1.25g/kg mtraperitoneally) and blood pressure and heart rate are recorded as described by Fozard J.R. et al., J. Cardiovasc. Pharmacol. 2, 229-245 (1980). A submaximal dose of 5-HT (usually 6μg/kg) is given repeatedly by the intravenous route and changes in heart rate quantified. Compounds are given intravenously and the concentration required to reduce the 5-HT-evoked response to 50% of the control response (ED^ Q ) is then determined.

Claims: Claims 1. A compound of formula (I) or a pharmaceutically acceptable salt thereof: (I) wherein X is a phenyl group or a monocyclic 5 or 6 membered heteroaryl group, either of which group is optionally fused to a saturated or unsaturated 5-7 membered carbocyclic or heterocyclic ring; A is a linking moiety; Z is C-L_g alkyl, C3_g cycloalkyl, C3_ cycloalkyl C^_^ alkyl, phenyl, naphthyl, phenyl C- ]L _ 4 alkyl or naphthyl C 1-4 alkyl wherein a phenyl or naphthyl moiety is optionally substituted by one or more of halo, Cι_g alkoxy or C-^_ alkyl; R is hydrogen or methyl; having 5-HT3 receptor antagonist activity. 2. A compound according to claim 1 wherein A is CONH, NHCONH, CONHCONH or a group of structure (j) : wherein the dotted circle represents two double bonds in any position in the 5 membered ring; two of G, H and I are selected from oxygen, sulphur, nitrogen and carbon and the other is oxygen, sulphur or nitrogen; and E is a bond or C--_5 alkylene optionally substituted by phenyl or hydroxy. 3. A compound according to claim 1, of formula (IA) , or a pharmaceutically acceptable salt thereof: (IA) wherein Y is NH or 0 (or is joined to R-^Q as defined below) ; X-L is a group of formula (a) , (b) , (c) , (d) , (e) , (f) , or (g) or (h) : 10 25 (e) wherein R a to R e and R Q . to R h are selected from hydrogen, halogen or hydroxy; R^ is hydrogen and R2 is hydrogen or C^_ 4 alkyl; or R-- and R2 together are a bond; R3 to R 7 are independently hydrogen or C-^ alkyl; and R 4 together with R2 may be C2_7 polymethylene or C2_g polymethylene interrupted by an -0- linkage when R-^ is hydrogen; Rg and Rg are independently selected from hydrogen or C- j __ alkyl or Rg and Rg together are C 2 _g polymethylene or C 2 _^ polymethylene interrupted by an -0- linkage; either R-^Q is hydrogen, C-^g alkoxy, C3_ cycloalkyloxy or c 3-8 cycloalkyl c ι-4 alkyloxy; or R 1Q is joined to Y so that Y _ Rχo ^ s N~B=N where B is N or CH; and - l is hydrogen, halo, C-^.g alkoxy or C-^.g alkyl; or R-- Q and -E- wherein E is (CH 2 ) n or NR 17 CO(CH 2 )m wherein n is 1 or 2 and m is 0 or 1 and Rικ, R^g and R 17 are independently selected from hydrogen or C--_g alkyl; R 12 is hydrogen, C^_g alkoxy or; amino optionally substituted by a C-^_g alkyl group, or R 12 is alkanoylamino; and alkylthio; R 14 is hydrogen or C-^.g alkyl; in formula (h) : CO-Y- is in the 1-position and either R 15 is in the 3-position and is hydrogen, C^_g alkyl or C-^_g alkoxy, or is in the 4-position and is hydrogen, halogen, CF3, C-L_g alkyl, C-^_η acyl, C-^_η acylamino, phenyl optionally substituted by one or two C-^g alkyl, C ] __g alkoxy or halogen groups, or amino, aminocarbonyl or aminosulphonyl, optionally substituted by one or two c l-6 alk yi or c 3-8 cycloalkyl groups or by C 4 _c- polymethylene or by phenyl, C-^g alkylsulphonyl, C-^. alkylsulphinyl, C-^.g alkoxy, C-^_g alkylthio, hydroxy or nitro; or CO-Y- is in the 3-ρosition and either R-^c- is in the 1-position and is hydrogen, C-^ alkyl or C^_ alkoxy, or is in the 4-position and is hydrogen or C η _ alkoxy; L is CH or N; and Z and R are as defined in claim 1. 4. A compound according to claim 3 wherein X is of sub-formula (a) , one of R-_ and R3 is hydrogen and R 2 and R 4 are both C-^- alkyl groups or are joined to form C 2 _ 7 polymethylene. 5. A compound according to claim 3 wherein X is of 5 sub-formula (b) , and Re- is hydrogen or a methyl or ethyl group. 6. A compound according to claim 3 wherein X is of sub-formula (d) and R 7 is methyl. 10 7. A compound according to claim 3 wherein X is of sub-formula (f) wherein R-^ Q is methoxy, R-^ s amino and R-^ is chloro or bromo. 15 8. A compound according to any one of claims 1 to 7, wherein Z is benzyl, n- or iso-butyl, n- or iso-propyl, ethyl or methyl. 9. endo-4-Amino-5-chloro-2-methoxy-N- (3-benzyl-9-methy1- 20 3, 9-diazabicyclo[3.3.1]nonan-7-yl)benzamide. 10. endo-4-Amino-5-chloro-2-methoxy-N- (3, 9-dimethyl-3, 9- diazabicyclo-[3.3.l]nonan-7-yl)benzamide. 25 11. endo-N-l-Methyl-3-indazolyl-(3-benzyl-9-methyl-3, 9- diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 12. endo-N-l-Methyl-3-indazolyl-(3-isopropyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 30 13. endo-N-l-Methyl-3-indazolyl- (9-methyl-3- n propyl-3, 9- diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 14. endo-N-l-Methyl-3-indazolyl- (3-isobutyl-9-methyl-3, 9- 5 diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 15. endo-N-l-Methyl-3-indazolyl- (3- n butyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 16. endo-N-l-Methyl-3-indazolyl-(3- (1-naρhthylmethyl)-9- 5 methyl-3, 9-diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 17. endo-N-l-Methyl-3-indazolyl- (3-ethyl-9-methyl-3, 9- diazabicyclo[3.3.1]nonan-7-yl) carboxamide. 10 18. endo-N-l-Methyl-3-indazolyl- (9-methyl-3-phenethyl- 3, 9-diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 19. endo-N-l-Methyl-3-indazolyl- (3-cyclohexylmethyl-9- methyl-3, 9-diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 15 20. endo-N-3, 3-Dimethylindolin-l-yl- (3-benzyl-9-methyl- 3, 9-diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 21. endo-N-3,3-Dimethylindolin-l-yl-(3-isopropyl-9- 20 methyl-3, 9-diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 22. endo-N-3, 3-Dimethylindolin-l-yl- (3, 9-dimethyl-3, 9- diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 2523. endo-N-3,3-Dimethylindolin-l-yl-(3-ethyl-9-methyl- 3, 9-diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 24. endo-N-3,3-Dimethylindolin-l-yl- (3- n propyl-9-methyl- 3, 9-diazabicyclo[3.3.l]nonan-7-yl)carboxamide. 30 25. endo-N-3,3-Dimethylindolin-l-yl- (3- n butyl-9-methy1- 3, 9-diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 26. endo-N-3, 3-Dimethylindolin-l-yl- (3-isobutyl-9-methyl- 3, 9-diazabicyclo[3.3.l]nonan-7-yl) carboxamide. 527. endo-N-3, 3-Dimethylindolin-l-yl- (3-cyclohexylmethyl-9- methyl-3, 9-diazabicyclo[3.3.1]nonan-7-yl carboxamide hydrochloride. 28. endo-N-3, 3-Dimethylindolin-l-yl- (9-methyl-3, 9- 10 diazabicyclo[3.3.1]nonan-7-yl)carboxamide. 29. A pharmaceutically acceptable salt of a compound according to any one of claims 9 to 28. 1530. A compound according to claim 1, substantially as described herein with reference to any one of the Examples. 31. A process for the preparation of a compound according to claim 1 which process comprises reacting a compound X'-A-^ 0 with a compound of formula (II) : (ID wherein -^ and 2 are moieties which react together, usually 0 by an amide or ester coupling, or by condensation to form a heterocycle (j) as defined in claim 2, to form A as defined in claim 1; X' is X or a group convertible thereto and R' and Z' are R and Z as defined in claim 1 or a hydrogenolysable protecting group; and thereafter as desired or necessary, converting X' to X, converting R'/Z', when other than R/Z, to R/Z, and optionally forming a 5 pharmaceutically acceptable salt of the compound of-formula (I) • 32. A process for the preparation of a compound according to claim 3, which process comprises reacting a compound of 10 formula (IV) : (IV) 15 with a compound of formula (V) : or a reactive derivative thereof, when Y is 0; 25 wherein X-- is X-^ or a group convertible thereto; Q-, is a leaving group; R' is R as defined, or a hydrogenolysable protecting group; and the remaining variables are as hereinbefore defined; and thereafter optionally converting X χ ' to X χ , including any R a , R b , R c , R d , R e , R g , R h or R 1Q , 30 Rχι, Rχ2- R 13' R 14 ° r R 15 g rou P to another such group, converting R' /Z' , when other than R/Z, to R/Z; and optionally forming a pharmaceutically acceptable salt of the resultant compound of formula (IA) . 3533. An intermediate of formula (V) wherein R' is R and Z' is Z, as defined in claim 32. 34. endo-3-Benzyl-9-methyl-3, 9-diazabicyclo[3.3.l]nonan-7- amine. 35. endo-3-Isopropyl-9-methyl-3, -diazabicyclo[3.3.1]- 5 nonan-7-amine. 36. endo-3- n Propyl-9-methyl-3, 9-diazabicyclo[3.3.1]- nonan-7-amine. 1037. endo-3-Isobutyl-9-methyl-3, 9-diazabicyclo[3.3.1]- nonan-7-amine. 38. endo-3- n Butyl-9-methy1-3, 9-diazabicyclo[3.3.1]nonan-7- amine. 15 39. endo-9-Methyl-3-phenyl-3, 9-diazabicyclo[3.3.1]nonan-7- amine. 40. endo-9-Methyl-3- (1-naphthylmethyl)-3,9-diaza- 20 bicyclo[3.3.1]nonan-7-amine. 41. exo/endo-3, 9-Dimethyl-3, 9-diazabicyclo[3.3.1]nonan-7- amine. 2542. endo-3-Ethyl-9-methy1-3, 9-diazabicyclo[3.3.1]nonan-7- amine. 43. endo-9-Methy1-3- (2-phenethyl)-3, 9-diazabicyclo- [3.3.1] onan-7-amine. 0 44. endo-3-Cyclohexylmethyl-9-methyl-3, 9-diazabicyclo- [3.3.1]nonan-7-amine. 45. A compound of formula (III)' (III)' wherein Z and R are as defined in claim 1. 46. 3-Benzyl-9-methyl-3, 9-diazabicyclo [3.3. l] nonan-7-one . 47. 3-Isopropyl-9-methyl-3, 9-diazabicyclo [3.3.1] nonan-7- one . 48. 3-n-Propyl-9-methy1-3, 9-diazabicyclo[3.3.l]nonan-7- one. 49. 3-Isobutyl-9-methyl-3, 9-diazabicyclo[3.3.1]nonan-7- one. 50. 3- n Butyl-9-methy1-3, 9-diazabicyclo[3.3.1]nonan-7-one. 51. 9-Methyl-3-phenyl-3, 9-diazabicyclo[3.3.1]nonan-7-one. 52. 9-Methyl-3- (1-naphthylmethyl)-3, 9-diazabicyclo- [3.3.1]nonan-7-one. 53. 3, 9-Dimethyl-3, 9-diazabicyclo[3.3.1]nonan-7-one. 54. 3-Ethyl-9-methyl-3, 9-diazabicyclo[3.3.1]nonan-7-one. 55. 9-Methyl-3-(2-phenethyl)-3, 9-diazabicyclo[3.3.1]- nonan-7-one. 56. 3-Cyclohexylmethyl-9-methyl-3, 9-diazabicyclo- [ 3.3.1 ] nonan-7-one . 57. A pharmaceutical composition comprising a compound according to any one of claims 1 to 30, and a pharmaceutically acceptable carrier. 558. A pharmaceutical composition for use in the treatment of pain, emesis, CNS disorders or gastrointestinal disorders comprising an effective amount of a compound according to claim 1, and a pharmaceutically acceptable carrier. 1059. A compound according to any one of claims 1 to 30, for use as an active therapeutic substance. 60. A compound according to any one of claims 1 to 30, for use in the treatment of pain, emesis, CNS disorders or 5 gastrointestinal disorders. 61. Use of a compound according to any one of claims 1 to 30, in the manufacture of a medicament for the treatment of pain, emesis, CNS disorders or gastrointestinal disorders. 0 62. A method of treatment of pain, emesis, CNS disorders or gastrointestinal disorders in mammals, which comprises the administration of an effective amount of a compound according to claim 1. 5

Inventors: GREGORY JULIAN ANTHONY, KING FRANCIS DAVID, GREGORY, JULIAN, ANTHONY, KING, FRANCIS, DAVID
Applicants: BEECHAM GROUP PLC
Application year: 1991
Main classification: A61K31
IPC codes: A61K31, A61P1, A61P25, A61P43, C07D471, C07D519