bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metalation of diazines. XI. Directed ortho‐lithiation of fluoropyrimidines and application to synthesis of an azacarboline
Authors: Plé N. , Turck A. , Heynderickx A. , Quéguiner G. 
Published: March 2009

AbstractFor the first time fluoropyrimidines were successfully lithiated. The resulting lithio derivatives were reacted with various electrophiles for the synthesis of new pyrimidines. The synthesis of an azacarboline derivative is reported.
Pyrimidine derivatives XII. A convenient preparation of 6‐formylpyrimidinedione and 2‐ and 3‐formylpyridine derivatives from corresponding nitrooxymethyl derivatives
Authors: Kinoshita Toshio , Ohishi Hiroshi 
Published: March 2009

AbstractThe convenient preparation of 6‐fomylpyrimidinedione derivatives and 2‐ and 3‐formylpyridine are described. Thus, 5‐bromo‐1,3‐dimethyl‐ (1a), 5‐bromo‐3‐methyl‐1‐(2‐nitrooxyethyl)‐ (1b), and 5‐bromo‐3‐methyl‐1‐(3‐nitrooxypropyl)‐2,4(1H,3H)‐pyrimidine‐dione (1c) were converted to the corresponding 6‐formyl compounds2a, 2b, and2c, respectively, in excellent yields by the reaction with triethylamine and 1,4‐diazabicyclo[2.2.2]octane. These 6‐formylpyrimidinedione derivatives are key intermediates for the preparation of 6‐carbon‐carbon substituted compounds, which are expected to be potential antitumor and antiviral agents. Similarly, 2‐(and 3‐)formylpyridine (9a(and9b)) were obtained by the reaction of 2‐(and 3)nitrooxymethylpyridine (8a(and8b)) with 1,4‐diazabicyclo[2.2.2]octane.
Reaction of azole condensed quinoxaline N‐oxides with acetic anhydride
Authors: Kurasawa Yoshihisa , Hosaka Tomoyoshi , Matsumoto Yuko , Ishikura Aiko , Ikeda Kazue , Takada Atsushi , Kim Ho Sik , Okamoto Yoshihisa 
Published: March 2009

AbstractThe reaction of 7‐chlorotetrazolo[1,5‐α]quinoxaline 5‐oxide 6a with acetic anhydride gave 7‐chloro‐5‐(7‐chlorotetrazolo[1,5‐α]quinoxalin‐4‐yl)‐4,5‐dihydro‐4‐oxotetrazolo[1,5‐α]quinoxaline 7a, while the reaction of 7‐chloro‐1,2,4‐triazolo[4,3‐α]quinoxaline 5‐oxide 6b with acetic anhydride afforded 7‐chloro‐5‐(7‐chloro‐1,2,4‐triazolo[4,3‐α]quinoxalin‐4‐yl)‐4,5‐dihydro‐4‐oxo‐1,2,4‐triazolo[4,3‐α]quinoxaline 7b and 7‐chloro‐4,5‐dihydro‐4‐oxo‐1,2,4‐triazolo[4,3‐α]quinoxaline 8b. The reaction of compound 6a or 6b with acetic anhydride/acetic acid provided 7‐chloro‐4,5‐dihydro‐4‐oxo‐tetrazolo[1,5‐α]quinoxaline 8a or compound 8b, respectively.
Formation of isoindoline derivatives from o‐bromoacetylbenzophenones
Authors: Nan'Ya Seiko , Ishida Hirofumi , Butsugan Yasuo 
Published: March 2009

Abstracto‐Dibromoacetylbenzophenone, 2 or o‐bromoacetylbenzophenone 3 reacted with aqueous ammonia to produce 3‐phenylisoindolin‐1‐one 5. The reaction of 3 with methylamine afforded 3‐hydroxy‐2‐methyl‐3‐phenyl‐isoindolin‐1‐one 4 and 2‐methyl‐3‐phenylisoindolin‐1‐one 5. Whereas from 2 with methylamine only 5 was obtained.
Syntheses and properties of selenium‐bridged bischromones
Authors: Löwe Wernexsr , Rütjes Thomas 
Published: March 2009

AbstractThe preparation of the new selenium‐bridged chromones 5a‐e is described. Compound 5c reacts with m‐CPBA under various conditions to give the corresponding selenoxide 7 and the Pummerer products 8 and 9. The selenides 5a‐c react with excess m‐CPBA to form the diselenides 13a‐c. Oxidation of 13c with hydrogen peroxide afforded the chromone‐3‐seleninic acid 22.
Preparation of 1,3‐disubstituted isoquinoline derivatives from N‐boc‐3‐substituted‐1,2‐dihydroisoquinolines
Authors: Clark Robin D. , Jahangir  
Published: March 2009

Abstract3‐Substituted N‐Boc‐1,2‐dihydroisoquinolines 2 can be functionalized at the 1‐position via lithiation and subsequent electrophilic trapping. The resulting products 3 can be deprotected and oxidized to afford the corresponding 1,3‐disubstituted isoquinolines 5. Deprotection of dihydroisoquinoline 3k followed by sodium borohydride reduction affords the cis‐1,3‐disubstituted tetrahydroisoquinoline 11. The 1,3‐disubstituted N‐Boc‐1,2‐dihydroisoquinoline 3g is efficiently alkylated at the 1‐position to give 1,1,3‐trisubstituted analogs 12.
A direct synthesis of α‐keto five‐ and six‐membered cyclic ethers
Authors: Enholm Eric J. , Schreier Jeffrey A. 
Published: March 2009

AbstractA simple synthesis of tetrahydro‐2H‐pyran‐2‐yl and tetrahydrofuran‐2‐yl ketones from their corresponding carboxylic acids was studied. A comparison was made of organolithium and Grignard alkylating reagents as a means of reducing the formation of byproducts and improving the yields.
Synthesis and properties of bilirubin analogs with one propionic acid group
Authors: Holmes Darren L. , Lightner David A. 
Published: March 2009

AbstractUnsymmetric bile pigment analogs of mesobilirubin‐XIIIα and mesobilirubin‐IVα were synthesized following oxidative coupling of dipyrrinones: methyl xanthobilirubinate with kryptopyrromethenone; methyl ψ‐xanthobilirubinate with kryptopyrromethenone.
Highly diastereoselective synthesis and NMR characterization of natural indolizidine alkaloids
Authors: Fleurant Anne , Saliou Chantal , Célérier Jean Pierre , Moc Thuy Vu , Lhommet Gérard , Platzer Nicole 
Published: March 2009

AbstractA diastereoselective, general and versatile access to disubstituted indolizidines is described. The nmr conformational analysis permits us to establish preferred conformations.
1,3‐Dipolar cycloaddition reactions of cyclooctyne with azomethine ylides
Authors: Matsumoto Kiyoshi , Ohta Ryuji , Uchida Takane , Nishioka Hiroyasu , Yoshida Maki , Kakehi Akikazu 
Published: March 2009

AbstractCyclooctyne smoothly underwent 1,3‐dipolar cycloaddition with aziridines and pyridinium ylides to afford the corresponding pyrroles and indolizines in moderate to good yields.
The synthesis of benzofuroquinolines. IX. A benzofuroisoquinolinone and a benzofuroisocoumarin
Authors: Yamaguchi Seiji , Uchiuzoh Yasuto , Sanada Kunio 
Published: March 2009

AbstractSome procedures for a benzofuroisoquinolinone 1 were studied. Its O‐analogous benzofuroisocoumarin 2 was synthesized from methyl salicylate with diethyl α‐bromohomophthalate (9). And, the benzofuroisoquinolinone 1 was obtained by treating 2 with ammonia gas in a sealed tube.
Palladium(0)‐catalyzed phenylation of imidazo[4,5‐b]pyridines
Authors: Grivas Spiros , Lindström Stefan 
Published: March 2009

AbstractThe tetrakis(triphenylphosphine)palladium(O)‐catalyzed coupling of benzeneboronic acid with 2‐chloro, 6‐bromo and 6‐bromo‐2‐chloro derivatives of 1‐ and 3‐methylimidazo[4,5‐b]pyridines to novel 2‐phenyl‐, 6‐phenyl‐ and 2,6‐diphenylimidazo[4,5‐b]pyridines is described. The phenylation of imidazo[4,5‐b]‐pyridines containing labile hydrogens was not successful.
Ring‐opening reactions of halogenated N‐aryl‐1,2,3,4‐tetrahydroisoquinoline and 2,3,4,5‐tetrahydro‐1H‐2‐benzazepine derivatives
Authors: Stanley Alan L. , Stanforth Stephen P. 
Published: March 2009

AbstractCompounds 4a‐4d, 4f and 10 were prepared and their ring‐opening reactions with N‐bromosuccinimide (NBS) investigated. Compounds 4a and 4b gave a mixture of products which did not contain any significant quantity of the corresponding aldehydes 5a and 5b whereas compounds 4c, 4d and 4f gave exclusively the aldehydes 5c, 5d and 5f respectively. Compound 10 similarly gave the aldehyde 11 when treated with NBS.
Synthesis of 5′‐halo‐2′,3′‐lyxo‐epoxy and 2′,3′‐unsaturated thieno[3,2‐d]pyrimidine nucleosides
Authors: Fossey Christine , Ladurée Daniel , Robba Max 
Published: March 2009

AbstractA series of thieno[3,2‐d]pyrimidine‐2,4‐dione nucleosides modified in the carbohydrate moiety has been synthesized. In the first part, synthetic routes are described for the replacement of 5′‐hydroxyl group in preformed 1‐(β‐D‐ribofuranosyl)thieno[3,2‐d]pyrimidine‐2,4‐dione I by fluoro, iodo or chloro atoms. Reduction of the 5′‐iodo substituent ofVIwas then carried out catalytically using palladium on carbon as catalyst to give the expected 5′‐deoxy derivativeVIII.Thelyxo‐epoxide derivativeXIIwas then synthesized by sequential treatment of the 5′‐deoxy‐5′‐chloro derivativeXwith methanesulfonyl chloride and with sodium hydroxide. In the second part, most of attention has been devoted to apply different methods reported in the literature that allow access to 2′,3′‐olefinic derivatives from the corresponding 2′,3′‐dihydroxy precursor. The 5′‐O‐silyl protected bisxanthateXIVeither on reduction with tri‐n‐butyltin hydride or by reductive elimination of the haloacetateXVIafforded the free 2′,3′‐olefin nucleoside after removal of the 5′‐protecting group. However none of the compounds in this series exhibited significant antiviral activity against HIV at the doses tested.
Synthesis of 1‐amino‐[1,2,3]oxadiazolo[4,3‐α]phthalazin‐4‐ium chloride and substituted dihydro derivatives. New annelated sydnonimines
Authors: Ruxer J. M. , Mauger J. , Bénard D. , Lachoux C. 
Published: March 2009

AbstractThe sydnonimine 5 has been prepared by an original one‐pot nitrosation and cyclisation procedure of the carbonyl chloride Reissert adduct 14 of phthalazine. This synthetic method could be extended to the preparation of dihydro derivatives 7a to 7f and represents a new access to annelated sydnonimines. The para anisoyl and ethoxycarbonyl derivatives of these sydnonimines were also prepared with analogy to molsidomine 1 or pirsidomine 2.
2,3,6,7,8,9‐hexahydro‐8,8‐dimethyl‐5‐phenyl‐1‐H1,4‐benzodiazepin‐6‐one
Authors: Egg Helmut , Knauseder Hubert , Mayr Sabine , Schöpf Daniela 
Published: March 2009

AbstractSeveral approaches for the synthesis of the title compound 1 were investigated. Treatment of the ethane‐1,2‐diamine derivative 2 with phosphoryl chloride afforded 3‐chloro‐5,5‐dimethylcyclohex‐2‐enone (3) and 1‐(5,5‐dimethyl‐3‐oxocyclohex‐1‐enyl)‐4,5‐dihydro‐2‐phenylimidazole (4), The reaction of 2‐benzoyl‐dimedone (5) with an equimolar amount of ethane‐1,2‐diamine led to the 2:1 adduct 6, whereas with an excess of ethane‐1,2‐diamine, 4,5‐dihydro‐2‐phenylimidazole (7) and dimedone were obtained. The synthesis of the title compound 1 was achieved by reacting 2‐benzoyl‐3‐chloro‐5,5‐dimethylcyclohex‐2‐enone (8) with ethane‐1,2‐diamine.
Reaction of 4‐chloropyrimidines with alkylisothioureas
Authors: Hurst Derek T. 
Published: March 2009

Abstract4,6‐Dichloro‐5‐nitropyrmidine reacts with S‐methylisothiouronium sulfate to give 1‐(4‐chloro‐5‐nitropyrimidin‐6‐yl)‐S‐methylisothiourea by an unusual nucleophilic attack involving an isothiouronium nitrogen atom.
Enzymatic resolution of trans‐2,3‐dihydro‐3‐hydroxy‐2‐phenyl‐4H‐1‐benzopyran‐4‐one (trans‐flavanon‐3‐ol) by lipase
Authors: Izumi Taeko , Murakami Satoshi 
Published: March 2009

Abstracttrans‐2,3‐Dihydro‐3‐hydroxy‐2‐phenyl‐4H‐l‐benzopyran‐4‐one (trans‐flavanon‐3‐ol) was resolved to acetate of (2S,3S)‐(‐)‐trans‐flavanon‐3‐ol and (2R,3R)‐(‐)‐trans‐flavanon‐3‐ol by an enzymatic transesterification with vinyl acetate in the presence of Pseudomonas cepacia lipase.
Synthesis of 2‐(3‐tropolonyl)‐1‐benzopyrylium perchlorates and related compounds
Authors: Wang Dao‐Lin , Lu Du‐Ren , Jin Zhong‐Tian , Imafuku Kimiaki 
Published: March 2009

Abstract3‐Acetyltropolone (1) reacted with 2‐hydroxybenzaldehyde (3a) in the presence of perchloric acid in ethyl orthoformate to afford 2‐(3‐tropolonyl)‐1‐benzopyrylium perchlorate (4a). The reactions with 2‐hydroxy‐5‐methylbenzaldehyde (3b), 5‐chloro‐2‐hydroxybenzaldehyde (3c), and 2‐hydroxy‐1‐naphthalde‐hyde (3d) gave respectively the corresponding products 4b‐d. The reactions of 2‐acetyl‐7‐methylamino‐tropone (2) with 3a‐d also gave the corresponding products 5a‐d, respectively.
Potential of alkyl orthoformates as alkylating agents of non‐electron rich nitrogen heterocycles
Authors: Guccione Salvatore , Russo Filippo , Raffaelli Andrea , Barretta Gloria Uccello , Pucci Sergio , Scolaro Luigi Monsu 
Published: March 2009

AbstractFindings and suggestions about the potential of the alkyl orthoformates as alkylating agents of non electron rich nitrogen heterocycles and unambiguous instrumental and chemical characterization of the alkylated compounds are reported.
Diheterocyclic compounds from dithiocarbamates and derivatives thereof. VII. 1‐(2‐benzazolylaminophenylsulphonyl)‐4‐[4‐oxo‐2‐thioxo(oxo)‐1,2,3,4‐tetrahydro‐3‐quinazolinyl]benzenes
Authors: Franco Santiago , Meléndez Enrique , Merchán Francisco L. 
Published: March 2009

AbstractBisheterocycles 8 with two different heterocyclic rings attached to the central benzene nucleus are readily synthesized from dithiocarbamic acid derivatives 4 or 5, using compound 1 as the starting material.
Synthesis of pyrimidine analogs of 2,6‐Di‐tert‐butylphenol antiinflammatory agents
Authors: Unangst Paul C. , Connor David T. , Kostlan Catherine R. , Shrum Gary P. , Miller Steven R. , Kanter Gerald 
Published: March 2009

AbstractThe preparation of pyrimidine analogs of the 2,6‐di‐tert‐butylphenol antiinflammatory agents Prifelone (R‐830), Tebufelone (NE‐11740) and Ym‐13,162 is described. Grignard addition to the N‐methoxy‐N‐methylamide derived from 4,6‐bis(1,1‐dimethylethyl)‐5‐hydroxy‐2‐pyrimidinecarboxylic acid yielded a series of 2‐pyrimidinyl ketones. Further elaboration of an ethyl ketone and cyclization with sodium cyanate gave a pyrimidinylimidazole.
An unusual structure of the hydrated sodium chloride complex of cryptand [2.2.2]
Authors: Dalley N. Kent , Bradshaw Jerald S. , Kou Xiaolan , Izatt Reed M. , Krakowiak Krzysztof E. 
Published: March 2009

AbstractThe solid state structure of the Na[2.2.2]C1·3H2O complex has the sodium ion displaced towards one of the cryptand nitrogens and the chloride and water molecules associated by hydrogen bonds to form a pseudo cube with two chloride ions at opposite corners of the cube and water oxygens at the other six corners.
Further evaluation of 5‐alkyl‐5‐deaza antifolates. 5‐propyl‐ and 5‐butyl‐5‐deaza analogues of aminopterin and methotrexate
Authors: Piper James R. , Ramamurthy Balakrishnan , Johnson Cheryl A. , Maddry Joseph A. , Otter Glenys M. , Sirotnak Francis M. 
Published: March 2009

Abstract5‐Propyl‐5‐deaza and 5‐butyl‐5‐deaza analogues of classical antifolates were synthesized by extensions of a previously reported general route which proceeds through 2,4‐diamino‐5‐alkylpyrido[2,3‐d]pyrimidine‐6‐carbonitrile intermediates followed by reductive condensation with diethyl N‐4‐(aminobenzoyl)‐L‐glutarnate to give diethyl esters of 5‐alkyl‐5‐deazaaminopterin types. N10‐Methyl derivatives, i.e., derivatives of 5‐alkyl‐5‐deazamethotrexate, were also prepared by reductive methylation of the N10‐H compounds. 5‐Ethyl‐5‐deazamethotrexate was prepared using an alternative route through 6‐(bromomethyl)‐2,4‐diamino‐5‐ethylpyrido[2,3‐d]pyrimidine. These antifolates were evaluated for inhibition of dihydrofolate reductase (DHFR) from L1210 cells, their effect on L1210 and S180 tumor cell growth in culture, and carrier‐mediated transport through L1210 cell membranes. Inhibitory effect on DHFR was lowered relative to methotrexate in 5‐propyl‐5‐deazaaminopterin and 5‐propyl‐5‐deazamethotrexate by 2‐ to 3‐fold (Ki = 9.3 and 11.7 pM, respectively, vs. 4.3 pM for methotrexate) and by 17‐ to 18‐fold in 5‐butyl‐5‐deaza‐aminopterin and 5‐butyl‐5‐deazamethotrexate (Ki = 74 and 78 pM, respectively). Molecular modeling using graphics derived from human DHFR show the propyl and butyl compounds interacting with the enzyme in conformations that account for these slight decreases in binding.
The synthesis of 2‐amino‐4‐aryl‐3‐ethoxycarbonyl‐4H‐naphtho[1,2‐b]pyrans revisited
Authors: Martín Nazario , Martínez‐Grau Angeles , Seoane Carlos , Marco José L. 
Published: March 2009

AbstractAn expeditious and unequivocal synthesis of some 2‐amino‐4‐aryl‐3‐ethoxycarbonyl‐4H‐naphtho‐[1,2‐b]pyrans 3 is reported. Previous papers describing the preparation of this type of compound have been amended and a convenient and direct procedure for its preparation is now presented.
Syntheses of substituted‐oxazolo‐1,3,4‐thiadiazoles, 1,3,4‐oxadiazoles, and 1,2,4‐triazoles
Authors: Shafiee A. , Naimi E. , Mansobi P. , Foroumadi A. , Shekari M. 
Published: March 2009

AbstractStarting from readily available methyl 5‐methyloxazole‐4‐carboxylate (1) and 4‐methyl‐5‐oxazolylcar‐boxylic acid hydrazide (11) the title compounds were prepared. The reaction of compound 1 with hydrazine hydrate afforded the corresponding hydrazide 2. The reaction of compound 2 with formic acid yielded 1‐formyl‐2‐(5‐methyloxazole‐4‐carboxyl)hydrazine (3). Refluxing of the latter with phosphorus pentasulfide in xylene gave compound 5 in 62% yield. The reaction of compound 3 with phosphorus pentoxide afforded compound 4. Starting from hydrazide 11, compounds 13 and 14 were prepared similarly. Reaction of compound 2 with substituted isothiocyanate yielded compound 9 which was cyclized in basic medium to 4‐alkyl‐5‐(5‐methyl‐4‐oxazolyl)‐2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thione (10). The isomer 19 was prepared similarly. Methylation and subsequent oxidation of compound 19 gave compound 21. Reaction of the acid 7 with thiosemicarbazide in the presence of phosphorus oxychloride gave 2‐amino‐5‐(5‐methyl‐4‐oxazolyl)1,3,4‐thiadiazole (8). 2‐Amino‐5‐(4‐methyl‐5‐oxazolyl)‐1,3,4‐thiadiazole (17) was prepared from acyl chloride 15 by the usual method.
Synthesis of N‐(3,5‐dichlorophenyl)‐2‐hydroxysuccinimide‐O‐sulfate: A potential metabolite of the nephrotoxicant N‐(3,5‐dichlorophenyl)succinimide
Authors: Hong Suk K. , Rankin Gary O. , Scott Kenneth R. 
Published: March 2009

AbstractThe sulfate conjugate 2 of N‐(3,5‐dichlorophenyl)‐2‐hydroxysuccinimide, a potential metabolite of the nephrotoxicant N‐(3,5‐dichlorophenyl)succinimide, is prepared from the 2‐hydroxysuccinimide (1) by the reaction with chlorosulfonic acid in chloroform and ether mixture at −78°.
Structure elucidation and spectral assignment of analogs of navelbine® (8′‐noranhydrovinblastine)
Authors: Spitzer Timothy D. , Reynolds Daniel W. , Crouch Ronald C. , Shockcor John P. , Johnson Robert L. , Morrison Robert W. , Martin Gary E. 
Published: March 2009

AbstractDuring the development of the bis‐indole alkaloid anticancer drug Navelbine® (vinorelbine), several chemical degradants of the drug were isolated and identified. These included 7′‐nor‐6′,9′‐secovinorelbine (7′,8′‐bisnor‐6′,9′‐secoanhydrovinblastine) and 4‐deacetyl‐8′‐vinorelbine (4‐deacetyl‐8′‐noranhydrovinblastine). The elucidation of the structure of 7′‐nor‐6′,9′‐secovinorelbine is described; the assignment of the proton and carbon spectra of both compounds is contrasted to the shift assignments of Navelbine.
A study of the mechanism of the oxidative cyclization of benzaldehyde semicarbazones induced by cupric perchlorate in acetonitrile
Authors: Noto Renato , Gruttadauria Michelangelo , Lo Meo Paolo , Frenna Vincenzo , Werber Giuseppe 
Published: March 2009

AbstractTreatment of benzaldehyde semicarbazones 1a‐i with cupric perchlorate in acetonitrile at 40 provided selectively the corresponding 1,2,4‐triazolin‐5‐ones 2a‐i. The relative rate constants for 2a‐i formation were determined by the competitive method. The results obtained showed that electron‐donating substituents (methyl and methoxy) increase the reaction rate, while the reverse was found for electron‐withdrawing substituents (chloro and nitro group). The reactivity data are discussed on the grounds of two possible mechanisms.
A practical synthesis of 5‐(chloromethyl)furo[2,3‐b]pyridine, a key intermediate for the HIV protease inhibitor, L‐754,394
Authors: Bhupathy M. , Conlon David A. , Wells Kenneth M. , Nelson John R. , Reider Paul J. , Rossen Kai , Sager Jess W. , Volante R. P. , Dorsey Bruce D. , Hoffman Jacob M. , Joseph Sally A. , Mcdaniel Stacey L. 
Published: March 2009

AbstractA practical synthesis of 5‐(chloromethyl)furo[2,3‐b]pyridine (10), the side chain used to incorporate a key pharmacophore of the HIV protease inhibitor, L‐754,394, is described. The synthesis was accomplished in ten steps and in 15% overall yield from commercially available methyl 2‐furoate.
A facile synthesis of 2‐acetylnaphtho[2,3‐b]furan‐4,9‐dione
Authors: Koyanagi Jyunichi , Yamamoto Katsumi , Nakayama Kouji , Tanaka Akira 
Published: March 2009

AbstractReaction of the parent naphtho[2,3‐b]furan‐4,9‐dione 2 with various electrophilic reagents was difficult, and only nitration of 2 gave small amounts of 2‐nitronaphtho[2,3‐b]furan‐4,9‐dione 4. Then 2‐acetylnaphtho[2,3‐b]furan‐4,9‐dione 1 was not obtained by the acetylation of 2. On the other hand, compound 1 that is isolated from Tabebuia Cassinoides and has cytotoxic activity, was obtained from 3‐lithiofuran in five steps.
Reactions of o‐bromoacetylacylphenones with several primary amines
Authors: Nan'ya Seiko , Ishida Hirofumi , Kanie Kiyoshi , Ito Noriyuki , Butsugan Yasuo 
Published: March 2009

Abstracto‐Monobromoacetylacylphenones, 3a and 3b reacted with hydroxylamine or hydrazine hydrate to produce heterocycles, 2,3‐benzoxazine or phthalazine derivatives. The reaction of bromoacetyl group of 3a and 3b with several thioamides afforded thiazole derivatives in high yields. Whereas o‐dibromoacetyl‐benzophenoe 2a reacted with aniline or cyclohexylamine to produce non‐heterocycles, 2‐substituted‐iminophenylindanones and the mechanism for the formation of these non‐heterocycles is proposed.
Synthesis and analysis of compounds having the skeleton of ergot alkaloids with the nitrogen atom in the D‐ring transposed
Authors: Stamos Ioannis K. , Kelly Elyse A. , Floss Heinz G. , Cassady John M. 
Published: March 2009

AbstractAlkylation‐amination of the enamine 2 in the presence of ethyl α,α‐bis(dibromomethyl)acetate, triethyl‐amine, and methylamine lead to the construction of the aza‐transposed ergoline 3. Sequential reduction, hydrolysis, reesterification, and indolization of 3, produced three diastereomers of 6. The structure of these three diastereomers was assigned on the basis of nmr and ir spectral analysis to be (α‐cis) syn, (β‐cis) anti, and (α‐trans) syn. The isomer (β‐cis) anti was reduced with lithium aluminum hydride to the corresponding alcohol.
Synthesis and reactivity of pyrrolo[1,2‐α]quinoxalines. Crystal structure and AM1 calculation
Authors: Blache Yves , Gueiffier Alain , Elhakmaoui Ahmed , Viols Henri , Chapat Jean‐Pierre , Chavignon Olivier , Teulade Jean‐Claude , Grassy Gérard , Dauphin Gérard , Carpy Alain 
Published: March 2009

Abstract2‐Methylquinoxaline reacts with ethyl bromopyruvate giving 2‐substituted pyrrolo[1,2‐α]quinoxalines. The yield of the condensation depends on the functionalization of starting materials, and optimization is obtained with 2‐dimethylamino‐3‐methylquinoxaline (1c). Reactivity of the resulting pyrrolo[1,2‐a]‐quinoxalines was investigated and supported by a theoretical approach (AM1 calculation performed with the MOPAC 6.0 software). X‐ray analysis of 5 which crystallizes in the monoclinic system, space group P21/n, with a = 9.095(1), b = 8.972(1), c = 17.749(3) A, β = 96.56(1)°, is also reported.
NMR spectroscopic investigations with ethyl 1‐(hetero)aryl‐5‐hydroxy‐1H‐pyrazole‐4‐carboxylates
Authors: Holzer Wolfgang , Schmid Eva 
Published: March 2009

AbstractThe synthesis of a series of ethyl N‐1‐(hetero)aryl‐5‐hydroxy‐1H‐pyrazole‐4‐carboxylates by reaction of diethyl ethoxymethylenemalonate with the appropriate hydrazines is described. According to nmr‐spectro‐scopic investigations (1H‐ and 13C‐nmr) the title compounds exist as 5‐hydroxy tautomers in deuteriochlo‐roform as well as in deuteriodimethyl sulfoxide solution.
N1‐substituted 3,5‐dimethoxy‐4‐halogeno‐1H‐pyrazoles: Synthesis and NMR study
Authors: Holzer Wolfgang , Gruber Heidi 
Published: March 2009

AbstractThe synthesis of 1‐methyl‐ and 1‐benzyl‐3,5‐dimethoxy‐4‐halogeno‐1H‐pyrazoles is described. Moreover, detailed nmr spectroscopic studies with the title compounds are presented. The highly shielded pyrazole C‐4 atom in the corresponding 4‐iodo congeners was found to have a 13C‐chemical shift of only −27 ppm.