bluuebunny/crossref_metadata_2025_split huggingface dataset:
Psilocin analogs II. Synthesis of 3‐[2‐(dialkylamino)ethyl]‐, 3‐[2‐(N‐methyl‐N‐alkylamino)ethyl]‐, and 3‐[2‐(cycloalkylamino)ethyl]indol‐4‐ols
Authors: Repke David B. , Ferguson Wilfred J. , Bates Dallas K. 
Published: March 2009

AbstractStructural alteration of theNb‐substituents of psilocin (3‐[2‐dimethylamino)ethyl]indol‐4‐ol) (12a) has led to a number of compounds containing known pharmacophoric groups. Further, it is hoped that the subtle changes in the nature of these substituents may lead to a clearer understanding of the structure‐activity relationships of the 4‐hydroxytryptamine hallucinogens.
A practical synthesis of pyoluteorin
Authors: Cue Berkeley W. , Dirlam John P. , Czuba Leonard J. , Windisch Wendell W. 
Published: March 2009

AbstractA convenient, large‐scale synthesis of the antibiotic pyoluteorin, 2,3‐dichloro‐5‐(2′,6′‐dihydroxybenzoyl)‐pyrrole (1), is described. A key step in the synthesis involved a Friedel‐Crafts aroylation of pyrrole with 2,6‐dimethoxybenzoyl chloride (3) in methylene chloride. The desired intermediate, 2‐(2′,6′‐dimethoxybenzoyl)pyrrole (4), was obtained as the major product, along with a product of beta substitution (6). Compound 4 was converted to pyoluteroin (1) in four steps in an overall yield of 51%.
The preparation of some 1‐(2‐furyl)‐2‐arylethylenes
Authors: Karminski‐Zamola G. , Jakopčić K. 
Published: March 2009

AbstractSome 1‐(2‐furyl)‐2‐arylethylenes, where the furan nucleus is substituted in position 5 with a methyl or p‐chlorophenyl group and where the aryl group is phenyl, p‐nitrophenyl, α‐naphthyl or β‐naphthyl, have been prepared by the Perkin reaction and subsequent decarboxylation of the acid. The compounds 1‐12 were prepared lor of photochemistry and photoelectron spectroscopy studies. Their geometrical configurations has been established by 1H nmr and ir spectra.
Phase‐transfer catalysis in the N‐benzylation of adenine
Authors: Shinkai I. , Vander Zwan M. C. , Hartner F. W. , Reamer R. A. , Tull R. J. , Weinstock L. M. 
Published: March 2009

AbstractA convenient phase‐transfer catalysis in the N‐benzylation of adenine is described. The benzylation of adenine with benzyl halides in a two‐phase system containing phase‐transfer catalyst gave 9‐benzylated adenines as a major product accompanied with 3‐benzylated adenines.
Oxidative ring‐expansion of benzothiazolines into 1,4‐benzothiazines
Authors: Liso Gaetano , Trapani Giuseppe , Latrofa Andrea , Marchini Paolo 
Published: March 2009

AbstractBy treatment in boiling DMSO, benzothiazolines 1 yield 1,4‐benzothiazines 4 in some cases together with benzothiazoles. Two competing pathways, namely oxidative ring‐expansion and decomposition of benzothiazoline accounting for the formation of 4 and benzothiazoles, respectively, are suggested.
The chemistry of carbazole. VI. On the formation of N‐ethylcarbazoles in the cadogan reaction
Authors: Tsunashima Yutaka , Kuroki Masatane 
Published: March 2009

AbstractReaction of 2′,6‐dimethyl‐2‐nitrobiphenyl with triethyl phosphite gave 4,5‐dimethyl‐9‐ethylcarbazole besides 4,5‐dimethylcarbazole. In this reaction, 4,5‐dimethylcarbazole was ethylated by triethyl N‐(2′,6‐dimethybiphenyl‐2‐yl)phosphorimidate and diethyl N‐(2′,6‐dimethylbiphenyl‐2‐yl)phosphoramidate, which arose from a nitrene‐intermediate and triethyl phosphite. Analogous ethylations of carbazole with other phosphorimidate and phosphoramidates were investigated.
Displacement‐cyclization reactions of mono‐substituted hydrazines with chloronitrobenzenes and chloronitropyrimidines. New routes to 8‐azapurine and benzopyrazole derivatives
Authors: Defusco A. A. , Strauss M. J. 
Published: March 2009

AbstractReactions of different chloronitrobenzenes and chloronitropyrimidines with monosubstituted hydrazines, R‐NHNH2, where R is methyl, carbomethoxy and phenyl, are described. The reactivity of these hydrazines in displacement‐ortho substituent cyclizations varies substantially, depending on the nature of the aromatic substrate and the hydrazine R group. New routes to 8‐azapurine and benzopyrazole derivatives are decribed.
Structural effects on the acidity of E‐α‐phenyl‐β‐arylacrylic acids
Authors: Maccarone Emanuele , Mamo Antonino , Perrini Giancarlo , Torre Michele 
Published: March 2009

AbstractThe dissociation equilibrium constants of some is‐α‐phenyl‐β‐arylacrylic acids (Ar = 2‐pyridyl, 3‐pyridyl, 4‐pyridyl, 1‐naphthyl, 2‐naphthyl, anthracen‐9‐yl) have been measured in 80% aqueous 2‐methoxyethanol at 25°. The pKa values of these acids, together with those of p‐substituted phenyl, 2‐furyl, 2‐thienyl and selenophen‐2‐yl derivatives, have been rationalized by an equation involving separate contributions of polar, conjugative and steric effects of heterocycles. The pKa values of some E‐α‐phenyl‐β‐alkylacrylic acids (alk = methyl; ethyl; n‐propyl; i‐propyl; n‐butyl; i‐butyl) are also reported.
Stereospecific synthesis of 2,3‐disubstituted 1,4‐benzodioxans
Authors: Proietti Gabriele , Corsano Stefano , Castagnino Enzo 
Published: March 2009

AbstractThe synthesis of cis‐ and trans‐2‐methyl‐3‐phenyl‐1,4‐benzodioxans 4 and 5, from 1‐phenyl‐2‐[2‐(hydroxy)‐phenoxy]propanols threo 2 and erythro 3 are described.
Cyclisation des amides d'acides phénylthio‐1 glyoxaliques avec les dérives carbonylés
Authors: Girault Pierre , Perronnet Jacques 
Published: March 2009

AbstractLes dérivés carbonylés reagissent sur les amides d'acides phénylthio‐1 glyoxaliques (3) en présence d'iodure de méthyle et provoquent leur cyclisation en dihydro‐2,5 méthylthio‐4 phényl‐5 oxazolols‐5 (4). L'hydroxyle hémiacétalique de ces composés peut ětre méthylé. Si un atome d'hydrogène existe en position 2 (cyclisation effectuée avec un aldéhyde) son élimination conduit à un oxazole, 7.
Coupling to the pyrimido[4,5‐b][1,4]oxazine ring system: Synthesis of potential antifolates
Authors: Winchester Merritt J. , Zappone Lawrence J. , Skinner Charles G. 
Published: March 2009

AbstractThe ability of 2‐amino‐4‐hydroxy‐7H‐pyrimido[4,5‐b][1,4]oxazine derivatives to inhibit dihydrofolate reductase led to a search for means of synthesizing new side chain substituted analogs of this marginally stable pyrimidooxazine system. A study of the synthesis and use of 6‐functionalized pyrimido[4,5‐b][1,4]oxazines for coupling side chains was begun and has now revealed methods for coupling p‐aminobenzoic acid with 2‐amino‐4‐hydroxy‐6‐carboxy‐7H‐pyrimido[4,5‐b][1,4]oxazine and hydrolyzed 2‐amino‐4‐hydroxy‐6‐carbe‐thoxymethylene‐6,7‐dihdyro‐5H‐pyrimido[4,5‐b][1,4]oxazine. The products are of interest for evaluation as potential antifolates.
Regioselective N‐alkylation of 1,2,6‐thiadiazine 1,1‐dioxide derivatives
Authors: Goya P. , Martínez P. , Ochoa C. , Stud M. 
Published: March 2009

AbstractReactivity towards alkylating agents in relation to the capacity to bind sodium ions of 1,2,6‐thiadiazine 1,1‐dioxide derivatives is described. The compounds studied are: 1, 4‐nitro‐, 2, 4‐cyano‐, 3,4‐ethoxycarbonyl‐2H,6H‐1,2,6‐thiadiazin‐3‐one 1,1‐dioxide and 4, 3‐amino‐4‐cyano‐6H‐1,2,6‐thiadiazine 1,1‐dioxide. Methylation with dimethyl sulfate of 4‐nitro‐ and 4‐cyanothiadiazines 1 and 2, which show the capacity to bind sodium ions, takes place regioselectively at position 2, whilst the thiadiazines which lack this feature (3 and 4) are methylated at 2 and 6, and 6 respectively. On using diazomethane, in the absence of alkaline ions, no selectivity was observed. Glycosidation reactions of 1, 3 and 4 have also been carried out. The structure of the newly synthesized compounds are discussed on the basis of their analytical and spectroscopic data.
Investigation of intramolecular sulfur‐nitro interactions in 2‐(2′‐pyridylthio)‐3‐nitropyridine by 13C‐NMR spectroscopy and x‐ray crystallography
Authors: Kimura Michio , Simonsen Stanley H. , Caldwell Steven R. , Martin Gary E. 
Published: March 2009

AbstractThe single crystal X‐ray diffraction structure of 2‐(2′‐pyridylthio)‐3‐nitropyridine is reported. A non‐bonded interaction was observed between the sulfur atom and one of the oxygen atoms of the nitro group with an interatomic distance of 2.678 A. Examination of the molecule's behavior in solution by 13C‐nmr spin‐lattice (T1) relaxation measurements showed the non‐nitro bearing pyridyl ring to reorient anisotropically about the C2′‐C5′ bond axis. In contrast, the nitro substituted pyridine ring did not appear to exhibit anisotropic reorientation about the corresponding C2‐C5 bond axis. Rather, approximately equivalent relaxation times were noted for all protonated ring carbons, indicating that the relaxations of this portion of the molecule were governed by the overall isotropic reorientation of the system. Based on these observations, it was concluded that the intramolecular sulfur‐nitro interaction also operates in the solution state and is sufficiently strong to prevent free rotation of the substituted portion of the molecule about the C2‐S bond axis.
A novel synthesis of 4,6‐dimethyl‐ and diphenyl‐2,5‐dihydro‐1,3,5,2‐triazaphosphorines
Authors: Li Ven‐Shun , Cates Lindley A. 
Published: March 2009

AbstractThe synthesis of 2,5‐dihydro‐1,3,5,2‐triazaphosphorines via the intramolecular cyclization of N,N'‐phos‐phinylacetamidines or benzamidines is described. These derivatives represent the sole examples of 4,6‐dialkyl or diaryl substitutions of this ring system.
Structure et synthèses nouvelles dans la série des amino‐4 dihydro‐5,6 méthyl‐6 pyrones‐2
Authors: Nedjar‐Kolli Bellara , Hamdi Maamar , Périé Jacques , Hérault Valentin 
Published: March 2009

AbstractL'étude de l'action des amines primaires et secondaires sur les dihydro‐5,6, hydroxy‐4 pyrones‐2 a tout d'abord permis de corriger un résultat antérieur: l'attaque du nucléophile a lieu sur l'atome de carbone en 4, et non sur celui en position 2, trop peu électrophile. Une nouvelle famille de composés dont certains ont des propriétés pharmacologiques intéressantes est ainsi développée. Par ailleurs les réactivités des dihydro‐5,6 pyrones et celles des pyrones parentes sont comparées.
Syntheses of some 2‐hydroxypyrazine 1‐oxides
Authors: Ohta Akihiro , Masano Sawako , Tsutsui Mayumi , Yamamoto Fusako , Suzuki Sumie , Makita Hiromi , Tamamura Hideo , Akita Yasuo 
Published: March 2009

AbstractA series of 2‐hydroxypyrazine 1‐oxides were prepared from the corresponding chloropyrazines by two methods, including oxidation processes in satisfactory yields. The treatment of 2,3‐diphenylpyrazine 1,4‐dioxide (6) led to 2,3‐dichloro‐5,6‐diphenylpyrazine (7) and 2‐chloro‐5,6‐diphenylpyrazine 1‐oxide (8), and the latter was converted to 5,6‐diphenyl‐2‐hydroxypyrazine 1‐oxide (9) by an alkaline hydrolysis.
Synthesis of methylpyridine derivatives. XXXV. Reaction of acetylpyridine with phosphoryl chloride to give alkynylpyridine
Authors: Kato Tetsuzo , Sato Masayuki , Wagai Akihiro 
Published: March 2009

AbstractReaction of 3‐acetyl‐4,6‐dimethyl‐2‐(1H)pyridone (9a) with phosphoryl chloride gives 2‐chloro‐3‐ethynyl‐4,6‐dimethylpyridine (10a). 3‐Acetyl‐4‐hydroxy‐6‐methyl‐2(1H)pyridone (14a) and 3‐acetyl‐2,6‐dimethyl‐4‐(1H)‐pyridone (21) undergoes similar reaction to give the corresponding ethynyl (16 and 23) and chlorovinyl (15 and 22) pyridines, respectively. The chlorination of 3‐acetylpyridine and pyrimidine derivatives is further described.
Mannich reaction on 2‐(2‐benzofuranyl)‐1H‐indole. Determination of structure by NMR spectroscopic techniques
Authors: Badger E. , Dicataldo S. , Kahle A. D. , Nadelson J. , Shapiro M. J. 
Published: March 2009

AbstractAnalysis of the product from the Mannich reaction of 2‐(2‐benzofuranyl)‐1H‐indole via 1H and 13C nmr spectroscopy was performed. The studies included use of Pr(Fod)3 shift reagent, proton‐coupled 13C spectra, deuterium isotope induced shifts and protonation studies. It was found that the reaction occurred on the indole moiety at C‐3.
1,2,4‐triazines. 1. A convenient synthesis of 4,5‐dihydro‐1,2,4‐triazin‐3‐(2H)one and its 6‐substituted derivatives
Authors: Nakayama Yoshinori , Sanemitsu Yuzuru , Mizutani Masato , Yoshioka Hirosuke 
Published: March 2009

AbstractA facile synthesis of 4,5‐dihydro‐1,2,4‐triazin‐3‐(2H)one (2a) from 5‐methylthio‐1,2,4‐triazin‐3‐(2H)one (1a) with sodium borohydride is described. The reaction provides a convenient method for its 6‐substituted derivatives (2b‐h).
Synthesis of 2,3‐disubstituted‐4‐oxothiazolidine 1‐oxides
Authors: Omar M. T. , El‐Khamry A. E. , Sherif F. A. 
Published: March 2009

AbstractThe reaction of chloramine‐T with 2,3‐disubstituted‐4‐oxothiazolidines 1a‐c give the corresponding sulfoxides 2a‐c, whose structures were based on analytical and spectral data.
The photochemical synthesis of 4‐acyl‐1,2‐dimethyl‐3H‐phenothiazin‐3‐ones
Authors: Ueno Yoshio , Takeuchi Yutaka , Koshitani Jinya , Yoshida Takatoshi 
Published: March 2009

Abstract4‐Acyl‐1,2‐dimethyl‐3H‐phenothiazin‐3‐ones were prepared by the photochemical reaction of 1,2‐dimethyl‐3H‐phenothiazin‐3‐one with aldehydes. The structures of the newly prepared compounds were determined by elemental analysis, spectroscopic methods (ir, nmr and ms) and comparison with a sample prepared by an alternate route.
Preparation of 2,4‐diarylquinolines and substituted dihydrobenz‐[c]acridines by the condensation of certain c(α),o‐dilithiooximes with 2‐aminobenzophenones
Authors: Park Dorothy J. , Fulmer Tammy D. , Beam Charles F. 
Published: March 2009

AbstractC(α),O‐Dilithiooximes were prepared in an excess of lithium diisopropylamide and condensed with several 2‐aminobenzophenones, followed by acid hydrolysis of the oximes to the ketones, which then underwent cyclodehydration and linear dehydration to give substituted quinolines or dihydrobenz[c]acridines.
The synthesis of proximal‐benzolumazine, proxirnal‐benzoxanthine, proximal‐benzotheophylline and proximal‐benzocaffeine
Authors: Schneller Stewart W. , Christ William J. 
Published: March 2009

AbstractThe synthesis of pyrazino[2,3‐f]quinazolin‐8,10‐(7H,9H)dione(proximal‐benzolumazine, 1), imidazo[4,5‐f]‐quinazolin‐7,9‐(6H,8H)‐dione (proximal‐benzoxanthine, 2), 6,8‐dimethylimidazo[4,5‐f]‐quinazolin‐7,9‐(6H,8H) dione (proximal‐benzotheophylline, 3), and 1,6,8‐trimethylimidazo[4,5‐f]quinazolin‐7,9‐(6H,8H)dione (proximal‐benzocaffeine, 4) is reported by commencing with 2‐amino‐6‐chlorobenzamide and proceeding via a variety of 5,6‐disubstituted‐2,4‐(1H,3H)quinazolinediones. Methylation of 3 is shown to yield 3,6,8‐trimethylimidazo[4,5‐f]quinazolin‐7,9‐(6H,8H)dione (15) and 4 in a ratio of 4:1.
Imidazo[1,2‐α]pyridine anthelmintics. Synthesis of 6‐phenylaminoimidazo[1,2‐α]pyridine‐2‐carbamate and 5‐acylaminopyridines by a chapman rearrangement
Authors: Peterson L. H. , Douglas A. W. , Tolman R. L. 
Published: March 2009

AbstractThe title compound, a potential anthelmintic agent, was prepared in seven steps from 5‐hydroxy‐2‐picoline. The intermediate 5‐(N,‐phenylbenzamido)‐2‐picoline was prepared by a facile Chapman rearrangement of the corresponding benzimidoyl ester. Oxidation and Curtius rearrangement of the substituted picoline gave 5‐(N‐phenylbenzamido)‐2‐aminopyridine which underwent ring closure and debenzoylation to furnish methyl 6‐phenylaminoimidazo[1,2‐α]pyridine‐2‐carbamate. Fries rearrangement of the penultimate N‐benzoyl derivative gave a 6‐(p‐benzoylphenylamino)imidazo[1,2‐α]pyridine derivative, whose structure was confirmed by cmr study. The title compound lacked significant anthelmintic activity.
Pyoluteorin derivatives. II. Synthetic approaches to pyrrole ring substituted pyoluteorins
Authors: Cue Berkeley W. , Chamberlain Nancy 
Published: March 2009

AbstractA method for the regiospecific synthesis of 3‐substituted 2‐aroylpyrroles is described. These pyrroles, which are structurally related to the naturally occurring antibiotic pyoluteorin, are prepared by a Friedel‐Crafts aroylation of 4‐substituted pyrrole‐3‐carboxylic acid esters with 2,6‐dimethoxybenzoyl chloride. The carboalkoxy group is then removed by hydrolysis and decarboxylation to produce isomerically pure 3‐substituted‐2‐(2′,6′‐dimethoxybenzoyl)pyrroles (5 and 13). Conversion of these pyrroles into pyoluteorin‐like compounds led to some unexpected products which arise from facile cleavage of the dihydroxybenzoyl portion of the molecules during chlorination.
The thiomethylation of substituted glutarimides
Authors: Seitz David E. , Needham Fang‐Ling 
Published: March 2009

AbstractConditions for the mono‐ and di(thiomethylation) of N‐methyl‐3‐ethyl‐3‐phenylpiperidine‐2,6‐dione and the monothiomethylation of N‐methyl‐3‐(4‐aminophenyl)‐3‐ethylpiperidine‐2,6‐dione, potential inhibitors of estrogen synthetase, are described and contrasted with a closely related lactam, N‐methylpiperidone. The influence of solvent, base and electrophile on product distribution is explored.
Synthesis of 4,10‐dihydro‐4,10‐dioxo‐1H‐[1]‐benzopyrano[3,2‐b]pyridine, 4,5‐Dihydro‐4,5‐dioxo‐1H‐[1]‐benzopyrano[2,3–6]pyridine and 1,5‐Dihydro‐1,5‐dioxo‐4H‐[1]‐benzopyrano[3,4‐b]pyridine derivatives from aminobenzopyrones
Authors: Connor David T. , Young Patricia A. , Von Strandtmann Maximilian 
Published: March 2009

Abstract3‐Aminochromone and 3‐aminocoumarin were condensed with diethyl ethoxymethylenemalonate and with dimethyl acetylenedicarboxylate to give intermediates, which were thermally cyclized to give 4,10‐dihydro‐4,10‐dioxo‐lH‐[1]‐benzopyrano[3,2‐b]pyridinecarboxylates and 1,5‐dihydro‐1,5‐dioxo‐4H‐[1]‐benzopyrano‐[3,4‐b]pyridinecarboxylates. 2‐Aminochromone was converted to 4,5‐dihydro‐4,5‐dioxo‐1H‐[1]‐benzopyrano‐[2,3‐b]pyridinecarboxylate via an intermediate condensation product with diethyl ethoxymethylenemalonate. These esters were hydrolyzed to the corresponding carboxylic acids (21, 30, 36, 50, and 60). Attempts to prepare 4,5‐dihydro‐4,5‐dioxo‐1H‐[1]‐benzopyrano[4,3‐b]pyridinecarboxylates from 4‐aminocoumarin were unsuccessful.
Nouvelles voies d'accès à des aryl‐4 thiéno[2,3‐c]pyridines et à des aryl‐7 thiéno[3,2‐c]pyridines
Authors: Maffrand Jean‐Pierre , Boigegrain Robert , Courregelongue Jean , Ferrand Gerard , Frehel Daniel 
Published: March 2009

AbstractDes aryl‐4 thiéno[2,3‐c]pyridines et des aryl‐7 thiéno[3,2‐c]pyridines ont été respectivement obtenues par chauffage dans l'acide polyphosphorique de [thényl‐2 amino]‐2 aryl‐1 éthanols ou propanols et de [thényl‐3 amino]‐2 aryl‐1 éthanols ou propanols. La transposition de Beckmann d'oximes d'aryl‐4 dihydro‐4,5 6H‐cyclopenta[b]thiophènone‐6, conduit à des aryl‐4 dihydro‐4,5 6H‐thiéno[2,3‐c]pyridones‐7.
Pyrrolo[1,2‐a]thieno[3,2‐e]pyrazines
Authors: Rault Sylvain , De Sévricourt Michel Cugnon , Dung Nguyen‐Huy , Robba Max 
Published: March 2009

AbstractLa dihydro‐4,5 oxo‐5 pyrrolo[1,2‐a]thiéno[3,2]pyrazine 6 et ses dérivés sont accessibles par cyclisation intramoléculaire de l'azoture de (pyrrolyl‐1)‐2 thénoyle‐3 2. La synthèse de la pyrrolo[1,2‐a]thiéno[3,2‐e]pyrazine 10 est réalisable soit par déshydrazination du dérivé 14 soit à partir de la (pyrrolyl‐1)‐2 thiénylamine‐3 4. Les spectres de rmn sont étudiés.
Reissert compound studies. XLI. Synthesis and reactions of the pyrrolo[1,2‐α]quinoxaline reissert compound and its analogs
Authors: Veeraraghavan S. , Popp F. D. 
Published: March 2009

AbstractReaction of pyrrolo[1,2‐α]quinoxaline, either by the phase‐transfer catalyst method or by the trimethylsilyl cyanide method, yielded the Reissert compound, 5‐benzoyl‐4‐cyano‐4,5‐dihydropyrrolo[1,2‐α]quinoxaline. This Reissert compound rearranged to 4‐benzoylpyrrolo[1,2‐α]quinoxaline upon sodium hydride treatment. It also underwent methylation with methyl iodide and sodium hydride. A few Reissert analogs of the pyrroloquinoxaline were also prepared and their reactions studied.
Synthesis of 5H‐benzothiazolo[3,2‐a]quinazolin‐5‐ones
Authors: Kim Dong Han 
Published: March 2009

Abstract5H‐Benzothiazolo[3,2‐a]quinazolin‐5‐ones (Va‐d) were synthesized by thermal cyclization of N‐(2‐benzothiazolyl)‐2‐fluorobenzamides (IVa‐d) which were obtained by allowing 2‐fluorobenzoyl chloride to react with 2‐aminobenzothiazoles.
Synthesis of some imidazole‐ and pyrazole‐ derived chelating agents
Authors: Addison Anthony W. , Burke Philip J. 
Published: March 2009

AbstractProcedures involving condensation of o‐phenylenediamines with carboxylic acids, and reaction of bifunctional alkyl halides with bifunctional nucleophiles are described. Syntheses are reported of 2,6‐bis‐(2‐benzimidazyl)‐pyridine, 1,3‐bis(2‐benzimidazyl)‐2‐thiapropane, 1,7‐bis(2‐benzimidazyl)‐2,6‐dithiaheptane, 2‐hydroxymethyl‐5,6‐dimethylbenzimidazole, 2‐chloromethyl‐5,6‐dimethylbenzimidazole hydrochloride, 1,7‐bis(5,6‐dimethyl‐2‐benzimidazyl)‐2,6‐dithiaheptane, 3,6‐bis(1‐pyrazolyl)pyridazine, 2‐(2‐hydroxy‐3‐methyl–phenyl)benzimidazole, 2‐(2‐hydroxyphenyl)benzimidazole, 5‐(2‐hydroxphenyl)‐3‐methyl‐1‐phenylpyrazole, 3(5)‐(2‐hydroxyphenyl)‐5(3)‐methylpyrazole, 3(5)‐(2‐hydroxyphenyl)‐5(3)‐phenylpyrazole, and 1,3‐bis((5‐methylpyridyl)imino)isoindoline.
Novel tetracyclic spiropiperidines. II. Synthesis of 2‐aryl‐2,3‐dihydrospiro[benzofuran‐3,4′‐piperidines]
Authors: Ong Helen H. , Agnew Marc N. 
Published: March 2009

AbstractA series of 2‐aryl‐2,3‐dihydropsiro[benzofuran‐3,4′‐piperidines] has been synthesized as potential psychotropic agentsviaan efficient intramolecular fluorine displacement reaction. Treatment of a key intermediate, 4‐cyano‐4‐(2‐fluorophenyl)‐1‐methylpiperidine (2), with a large excess of phenylmagnesium bromide in refluxing tetrahydrofuran led to some 2‐arylspiro[3H‐indole‐3,4′‐piperidine] derivatives,10and11, whose structures are elucidated on the basis of chemical and spectral evidence.
The synthesis of 1‐haloalkyl‐1,3,4,5‐tetrahydro‐2‐benzoxepins
Authors: Tenbrink Ruth E. , Mccall John M. 
Published: March 2009

AbstractShort, efficient routes to several 7,8‐dimethoxy‐1‐haloalkyl‐1,3,4,5‐tetrahydro‐2‐benzoxepins were developed. These benzoxepins were prepared by the Lewis acid catalyzed condensation of the acetals of chloropropionaldehyde or bromoacetaldehyde with 3‐(3,4‐dimethoxyphenyl)‐1‐propanol. This condensation was facilitated by methyl substitution on the propanol. In an alternate route, ethyl 3‐(3,4‐dimethoxyphenyl)propanoate was acylated with 3‐chloropropionyl chloride. The adduct was reduced with lithium aluminum hydride. The resultant 3‐[2‐(3‐chloro‐1‐hydroxypropyl)‐4,5‐dimethoxyphenyl]propanol was dehydrated to the corresponding tetrahydrobenzoxepin. By these two general routes, 7,8‐dimethoxy‐1,3,4,5‐tetrahydro‐2‐benzoxepins were produced which were substituted by hydrogen or methyl at benzoxepin C‐4 and chloroethyl or bromomethyl at benzoxepin C‐1.
Synthesis of 4‐acyl‐2,3‐dihydro‐4H‐1,4‐oxazines
Authors: Nicola Massimo , Gaviraghi Giovanni , Pinza Mario , Pifferi Giorgio 
Published: March 2009

AbstractThe synthesis of 4‐acyl‐2,3‐dihydro‐4H‐1,4‐oxazines (6a‐h) via acid dehydration of 4‐acyl 2‐ and 3‐morpholinols is described. During dehydration of 2‐morpholinols 3d,e, N‐alkylisoquinolones 7a‐e were also isolated.
An improvement in the synthesis of ethyl pyrimidinecarbamates
Authors: Auzou Gilles , Rips Richard 
Published: March 2009

AbstractIt is demonstrated that N‐(ethoxycarbony])pyridinium chloride (3) is the reactive agent in the synthesis of 4‐ethoxycarbonylamino‐2,6‐dimethylpyrimidine (1). A good yield (80%) of 1 may be obtained by the condensation of 3 with excess 4‐amino‐2,6‐dimethylpyrimidine using pyridine or dimethylformamide as the solvent. A method allowing for the preparation of 4‐ethoxycarbonylamino‐x‐hydroxypyrimidines via the same process is offered.
Anti‐configuration of the N = N bond in azobilirubin pigments
Authors: Salmón Manuel , Rubio Manuel , Cetina Raul 
Published: March 2009

AbstractThe conformational and internal energy barriers for rotation of the phenylazo group in azobilirubin pigments were determined by the PCILO method. The calculations showed a restricted rotation of the azo group at 180–300° dihedral angle.
Cyanogen bromide as a reagent for lactone formation. Preparation of dibenz[b,e][1,4]oxazepin‐11‐(5H)ones
Authors: Kim Dong Han 
Published: March 2009

AbstractThe treatment of N‐(2‐hydroxyphenyl)anthranilic acids with cyanogen bromide in the presence of triethylamine gave dibenz[b,e][1,4]oxazepin‐11‐(5H)ones in good yields.