bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of some isomeric 4‐ethoxycarbonyl‐3‐and 5‐(1‐ and 2‐hydroxyalkyl)‐1,3‐ and 1,5‐dimethylpyrazoles from 3‐(2H)furanones and 2,3‐dihydro‐4‐pyrones
Authors: Gelin Suzanne , Deshayes Christian , Chabannet Michel 
Published: April 2009

AbstractThe title compounds were prepared by reaction of 3‐(2H)furanones and 2,3‐dihydro‐4‐pyrones with methylhydrazine or alternatively by methylation of the corresponding N‐unsubstituted pyrazoles. 13C and 1H nmr were used to assign the isomeric 3‐methyl or 5‐methyl structures.
Synthesis of 3‐arylsulfonylmethyl‐1,2,4‐oxadiazole‐5‐carboxylic acid derivatives
Authors: Santilli Arthur A. , Morris Robert L. 
Published: April 2009

AbstractSeveral new 3‐arylsulfonylmethyl‐1,2,4‐oxadiazole‐5‐carboxylic acid derivatives have been synthesized. A typical example, 3‐[(4‐chlorophenylsulfonyl)methyl]‐1,2,4‐oxadiazole‐5‐carboxylic acid ethyl ester (2c), was prepared from the reaction of 2‐(4‐chlorophenylsulfonyl)acetamide oxime (1c) with ethyl oxalyl chloride. The hydrazide derivative (3f) showed antihypertensive activity in rats. Various structural modifications to improve activity are discussed.
Dérivés de l'imidazo[2,1–b] thiazole. IV. Réarrangements au cours de la condensation de β‐dicétones α‐bromées avec l'amino‐2 thiazole et la mercapto‐2 imidazoline
Authors: Robert Jean FranÇOis , Panouse Jacques J. 
Published: April 2009

AbstractAu cours de la condensation des β‐dicétones α‐bromées sur l'amino‐2 thiazole et la mercapto‐2 imidazoline, la formation d'acétyl (ou benzoyl) imino‐2 acétonyl (ou phénacyl)‐3 thiazolines et d'acétyl (ou benzoyl)‐1 acétonyl (ou phénacyl) thio‐2 imidazolines est observée. L'obtention de ces composés résulte d'un réarrangement après ouverture, par attaque nucléophile, d'une carbinolamine intermédiaire. Ce réarrangement est univoque dans le cas de β‐dicétone dis‐symétrique.
Triazino‐1,2,4‐[4,5‐a] indoles. V. Etude du dioxo‐1,4 tetrahydro‐1,2,3,4 triazino‐1,2,4‐[4,5‐a] indole
Authors: Maume Daniel , Lancelot Jean‐Charles , Robba Max 
Published: April 2009

AbstractLe dioxo‐1,4 tétrahydro‐1,2,3,4 triazino‐1,2,4‐[4,5‐a] indole (1) est synthétisé soit par cyclisation du N‐carbéthoxyhydrazide de l'acide indole carboxylique‐2 (4) soil par réarrangement en milieu alcalin de l'(indolyl‐2)‐2 oxadiazolone‐5 (6). Les réactions de méthylation du dérivé 1, effectuées au moyen du sulfate diméthylique el du diazométhane, ont conduit à des mélanges de dérivés O‐méthylés et N‐méthylés qui sont séparés et dont la structure est établie. Ils sont utilisés comme modèles pour l'étude de la tautoméric du dilactame 1 qui présente en solution une forme lactame‐lactime 1a.
Carbon‐13 and proton magnetic resonance spectra of 2,4‐disubstituted 3,3‐diphenyltetrahydrofurans derived from isomethadone and isomethadol
Authors: Williams David A. , Makriyannis Alexandros 
Published: April 2009

AbstractProton and carbon‐13 nmr spectra forcis‐andtrans‐2‐ethyl‐3,3‐diphenyl‐4‐methyltetrahydrofurans and 2‐ethylidene‐3,3‐diphenyl‐4‐methyltetrahydrofuran, derived from the pyrolysis of the quaternary ammonium salts of the diastereomeric isomethadols and isomethadone, respectively, are reported.1H and13C chemical shifts and1H‐1H coupling constants have been assigned in each case. The isomeric teterahydrofurans have been analyzed in terms of a half‐chair conformation, and an envelope conformation for the ethylidene derivative.
The synthesis of 6,9‐dioxo‐, 6,9‐ and 7,9‐dihydroxyehlorpromazines, possible metabolites of chlorpromazinem
Authors: Suzuki Joseph K. , Zirnis Aija , Manian Albert A. 
Published: April 2009

AbstractThe syntheses of dioxogenated chlorpromazines 1, 2, and 3 via the reductive ring closure of substituted nitrodiphenyl sulfides are described.
Synthesis of N‐ethoxycarbonyl‐7‐azabicyclo[4.2.1]nonane and N‐ethoxycarbonyl‐9‐azabicyclo[4.2.1]nonane
Authors: Loreto M. Antonietta , Pellacani Lucio , Tardella Paolo A. 
Published: April 2009

AbstractThe synthesis of N‐ethoxycarbonyl‐7‐azabicyclo[4.2.1]nonane and N‐ethoxycarbonyl‐9‐azabicyclo[4.2.1]nonane, starting from bicyclo[5.1.0]octan‐2‐one, is described. The key step is the cyclopropyl ring fission by pyridinium chloride.
Photolysis of 1‐o‐iodobenzoylbenzimidazoles
Authors: Nakano Tatsuhiko , Martin A. 
Published: April 2009

AbstractIrradiations of 1‐o‐iodobenzoyl‐2‐methylbenzimidazole, 1‐o‐iodobenzoylbenzimidazole, and 1‐o‐iodobenzoyl‐5,6‐dimethylbenzimidazole in benzene gave compounds 1, 2, and 3, respectively. The fragmentation patterns of these latter compounds upon electron impact are also reported with the aid of high resolution mass spectrometry.
Streptonigrin and related compounds IV. Precursors for the a‐ring
Authors: Rao Koppaka V. , Kuo Hsien‐Saw 
Published: April 2009

AbstractThe synthesis of streptonigrin or its tricyclic (ABC) analogues by the Friedlander condensation requires a 2‐nitrobenzaldehyde with all the necessary functionalities. A number of alternative syntheses are examined. It is shown that oxidation of 8‐amino‐5,6‐dimethoxy‐2,2‐pyridylquinoline leads to 8‐amino‐2,2‐pyridylqunoline‐5,6‐dione instead of 6‐methoxy‐2,2‐pyridylquinoline‐5,8‐dione. The synthesis of two useful precursors: 4‐bromo‐3‐hydroxy‐5,6‐dimethoxy‐2‐nitrobenzaldehyde and 4‐bromo‐3‐hydroxy‐5‐methoxy‐2‐nitrobenzaldehyde is described.
2,3,5,6‐Tetramethylmorpholine. IV. The observation of a new cyclization mechanism
Authors: Hernestam Sven 
Published: April 2009

AbstractA new type of cyclization, implying the simultaneous inversion of configuration at the reacting carbon atom and at the carbon atom bearing the nucleophilic group, is observed when two 3,3′‐iminobis‐2‐butanols are dehydrated by 70% sulfuric acid at 140–150°.
Ring‐chain tautomerism of acetone N‐methylated thiosemicarbazones
Authors: Uda Masayuki , Kubota Seiju 
Published: April 2009

AbstractRing‐chain tautomerism of acetone N‐methylated thiosemicarbazones was studied by nmr spectroscopy. Acetone thiosemicarbazone, acetone 2‐methylthiosemicarbazone, and acetone 4‐methylthiosemicarbazone exist as chain forms in DMSO‐d6 and ring forms in deuteriotrifluoroacetic acid. However, the compound obtained by reaction of acetone with 2,4‐dimethylthiosemicarbazide exists only as the ring form 3,5,5‐trimethyl‐1,3,4‐thiadiazolidine‐2‐methylimine both in DMSO‐d6 and in deuteriotrifluoroacetic acid, due to steric hindrance of the three methyl groups.
Synthesis of 1‐(2,4,6‐trichlorophenyl)‐3‐(3‐nitro‐ and 2‐chloro‐5‐nitroanilino)‐5‐pyrazolones
Authors: Tracy David J. 
Published: April 2009

AbstractA convenient one flask synthesis of 1‐aryl‐3‐nitroanilino‐5‐pyrazolones in yields of 60–65% is described. Synthesis involves initial reaction of ethyl 3‐ethoxy‐3‐iminopropionate hydrochloride and a nitroaniline in methanol producing an imidate ester. The imidate ester is then reacted with an arylhydrazine forming an amidine. The amidine is then cyclized with base.
Oxidation of pyridines with copper sulfate
Authors: Tomasik Piotr , Woszczyk Adam , Abramovitch Rudolph A. 
Published: April 2009

AbstractOxidation of pyridine, 3‐picoline, 3,5‐lutidine, quinoline, isoquinoline and acridine with hydrated copper sulfate at high temperatures gives the corresponding pyridones, possibly via the intramolecular reaction of a base ‐ Cu(II) complex. Overall conversions are rather poor. 2‐ And 4‐picolines and their methyl homologues undergo some demethylation under these conditions and some picolinic acid is isolated from 2‐picoline. 2‐ And 4‐ethylpyridines give both pyridine and 2‐ and 4‐picoline, respectively.
Catalytic effect of ammonium chloride on the synthesis of imidate esters
Authors: Tracy David J. 
Published: April 2009

AbstractPreparation of imidate esters by reaction arylamines containing electron withdrawing groups with ethyl 3‐ethoxy‐3‐imino‐propionate in methanol is described. Evidence is presented for an orthoester intermediate. The unusual catalytic effect of ammonium chloride is discussed.
Benzo[b]thiophene derivatives. XXV. Condensation and reductive alkylation of 3‐aminoalkylbenzo[b]thiophenes with formaldehyde
Authors: Campaigne E. , Homfeld E. 
Published: April 2009

AbstractThe reductive alkylation of 3‐aminomethylbenzo[b]thiophene by the Eschweiler‐Clarke (formaldehyde‐formic acid) method and of 3‐β‐aminoethylbenzo[b]thiophene by the Borch (formaldehyde‐cyanoborohydride) method proceeded in good yields. However, the Eschweiler‐Clarke reaction with 3‐β‐aminoethylbenzo[b]thiophene gave the Pictet‐Spengler cyclized product, N‐methyl‐1,2,3,4‐tetrahydrobenzo[b]thieno[2,3c]pyridine. Mechanistic aspects of the latter reaction were investigated.
Synthesis of 1,2,3,4,4a,5‐hexahydropyrido[1′,2′:4,5][1,4]oxazino[2,3‐b]quinoxaline derivatives
Authors: Wright William B. , Morton George O. , Tomcufcik Andrew S. 
Published: April 2009

AbstractReactions of 2,3‐dichloroquinoxalines with 2‐(hydroxymethyl)piperidine resulted in a series of 1,2,3,4,4a,5‐hexahydropyrido[1′,2′:4,5][1,4]oxazino[2,3‐b]quinoxaline derivatives. The structures of the products were confirmed by nmr and x‐ray crystallography.
Oxidation of bis‐arylacetylhydrazones of α‐dicarbonyl compounds
Authors: Stephanidou‐Stephanatou J. , Varella E. , Micromastoras E. D. , Alexandrou N. E. 
Published: April 2009

AbstractOxidation of the title compounds (IV) with lead tetraacetate gives, instead of the expected 1‐(α‐arylacetyloxyarylethyleneamino)‐1,2,3‐triazoles, the amides (V), 1‐(N‐arylacetylamino)‐1,2,3‐triazoles, as the main products in moderate yields. The reaction mechanism is discussed.
Selenium heterocycles. XXIV (1). 4‐Substituted vinyl and 4‐phenyl‐1,3‐butadienyl‐1,2,3‐selenadiazoles and related compounds
Authors: Lalezari Iraj , Shafiee Abbas , Sadeghi‐Milani Shahnaz 
Published: April 2009

AbstractA series of 4‐aryl (or heteroeyclic)‐3‐buten‐2‐one semicarbazones as well as 6‐phenyl‐3,5‐hexadien‐2‐one semicarbazone were reacted with selenium dioxide to give the corresponding 4‐substituted vinyl and 4‐phenyl‐1,2‐butadienyl‐1,2,3‐selenadiazoles. The selenadiazoles were converted to the corresponding 1,4‐diselenafulvenes. Pyrolysis of 4‐styryl‐1,2,3‐selenadiazole gave 2,5‐distyrylselenophene.
Studies on furan derivatives. V. A novel ethoxycarbonylmethylation of the 5‐nitro‐2‐furan ring in the reaction of α‐(2‐furyl)‐β‐(5‐nitro‐2‐furyl)ethynyl with N‐ethoxycarbonylmethylpyridinium ylide
Authors: Tanaka Akira , Usui Toshinao 
Published: April 2009

AbstractAn unexpected product, 1‐(4‐ethoxycarbonylmethyl‐5‐nitro‐2‐furyl)‐2‐(2‐furyl)‐3‐ethoxycarbonyl‐indolizine was obtained by the reaction of α‐(2‐furyl)‐β‐(5‐nitro‐2‐furyl)ethynyl with N‐ethoxy‐carbonylmethylpyridinium ylide in N,N‐dimethylformamide, together with 1‐(5‐nitro‐2‐furyl)‐2‐(2‐furyl)‐3‐ethoxycarbonylindolizine.
5‐Oxo‐1H‐4,5‐dihydro‐1,2,4‐benzotriazepines. Chemical behavior towards alkylating, acidic and alkaline agents
Authors: Bianchi Mario , Häusermann Enrico , Rossi Silvano 
Published: April 2009

AbstractThe chemical behavior of 4‐methyl and 4‐phenyl‐5‐oxo‐1H‐4,5‐dihydro‐1,2,4‐benzotriazepines towards methylating and acidic agents has been investigated. The 4‐methyl derivative, when treated with methyl fluorosulfonate furnished, after crystallization from water, a quaternary salt (2,4‐dimethyl‐5‐oxo‐1H‐4,5‐dihydro‐1,2,4‐benzotriazepinium fluorosulfonate), whereas from the 4‐phenyl derivative, a complex mixture was obtained, which, after boiling with water, afforded 2‐methylindazolone, aniline fluorosulfonate and formic acid. In acidic medium the 4‐methyl derivative underwent an isomerization reaction yielding 1‐imino‐3‐methylquinazolin‐4‐one, but the 4‐phenyl derivative exclusively yielded products resulting from ring opening. In alkaline medium, both compounds gave hydrolytic cleavage products.
The cyelodesulfurization of thio‐compounds. Part XVII. Synthesis of some novel 2‐substituted amino‐3,4‐dihydro‐5H‐1,3,4‐benzotriazepin‐5‐ones by cyelodesulfurization of thiosemicarbazides with dicyclohexylearbodiimide (DCCD)
Authors: Omar A.‐Mohsen M. E. , Ashour F. A. , Bourdais Jacques 
Published: April 2009

AbstractA simple method for the synthesis of a novel series of 2‐substituted amino‐3,4‐dihydro‐5H‐1,3,4‐benzotriazepin‐5‐ones (11–16) has been established through two routes. The first involving the cyelodesulfurization of the thiosemicarbazides (3–8) with DCCD and the second reacting mixtures of the acid hydrazide 1 with a variety of the isothiocyanates 2 and DCCD. The structure of the cyclized products was confirmed by nmr and mass spectra.
Studies on the synthesis of heterocyclic compounds. V. Preparation of 1,3,2‐benzoxathiaphosphole, arsole and stibole derivatives by exchange methods
Authors: Anchisi Carlo , Corda Luciana , Maccioni Antonio , Podda Gianni , Secci Mario 
Published: April 2009

AbstractA new convenient method for synthesis of heterocyclic compounds of five‐membered rings containing an O‐M‐S (M = P, As, Sb) linkage is described. The compounds IIIa‐c, IVa‐b, Va‐b, Viand VII were prepared starting from 2,2‐dimethyl‐1,3,2‐benzoxathiastannole (II) and derivatives of phosphorus, arsenic and antimony. The structures of newly prepared compounds was determined by elemental analysis, spectroscopic methods (ir, nmr and ms) and comparison with authentic samples obtained via a different manner.
Research on nitrogen heterocyclic compounds. XII. Synthesis of 5H‐pyrrolo[1,2‐b][2]benzazepine derivatives
Authors: Stefancich Giorgio , Artico Marino , Massa Silvio , Vomero Salvatore 
Published: April 2009

AbstractSeveral routes to the synthesis of the unknown 5H‐pyrrolo[1,2‐b][2]benzazepine ring system have been explored. 1‐(2‐Cyanobenzyl)pyrrole was useful as starting material to obtain 1‐(2‐earboxymelhylbenzyl)pyrrole and 1‐(2‐chloromethylbenzyl)‐2‐pyrrolecarboxaldehyde. Poly‐phosphoric acid catalyzed intramolecular cyclization of the former substance and treatment of the latter compound with potassium cyanide led to 11‐oxo‐10,11‐dihydro‐5H‐pyrrolo[1,2‐b]‐[2]benzazepine and to 10‐cyano‐5H‐pyrrolo[1,2‐b][2]benzazepine, respectively. Starting from these materials the synthesis of the parent nucleus 5H‐pyrrole[1,2‐b][2]benzazepine and its 10,11‐dihydro‐ and 1,2,3,10,11,11a‐hexahydroderivatives has been realized.
The nature of the fragmentation step for decarboxylation in heterocyclic carboxylic acids
Authors: Salmón M. , Villarino O. , Jiménez A. , Cortés E. , Damian C. 
Published: April 2009

AbstractA mechanism of fragmentation for five membered heterocyclic‐substituted acids is proposed. The suggested four centered transition state for the CO2 elimination is based on the resulting deuterium‐labelled ions.
Ipso nitration. Nitrodeformylation reactions in nitrothiophenealdehydes
Authors: Cogolli Pietro , Maiolo Filippo , Testaferri Lorenzo , Tiecco Marcello , Tingoli Marco 
Published: April 2009

AbstractNitration of 4‐nitro‐2‐thiophenealdehyde afforded 2,4‐dinitrothiophene and small quantities of 4,5‐dinitro‐2‐thiophenealdehyde; 5‐nitro‐2‐thiophenealdehyde gave instead 3,5‐dinitro‐2‐thiophenealdehyde as the main product and some 2,5‐dinitrothiophene. The two dinitrothiophenes form through a nitrodeformylation reaction which represents an interesting example of the nitration at an ipso position in a strongly deactivated substrate.
Proximate functionality induced restricted rotation of a carbamate: 2,6‐Dicarbethoxy‐7‐methoxy‐5,6‐dihydropyrrolo[1,2‐c]quinazoline
Authors: Cotter Mary Lou , Bandurco Victor , Wong Elizabeth 
Published: April 2009

AbstractThe 6‐carbethoxy group of 2,6‐dicarbethoxy‐7‐methoxy‐5,6‐dihydropyrrolo[1,2‐c]quinazoline (4) is observed by nmr to experience an unusual steric barrier to free rotation about the N‐CO bond which arises from the proximate 7‐methoxy group.
Novel nitroimidazo[2,1‐b]oxazole formation from reaction of 2,4(5)‐dinitroimidazole with oxiranes
Authors: Sehgal Raj K. , Agrawal Krishna C. 
Published: April 2009

AbstractA novel reaction for the synthesis of 2,3‐dihydroimidazo[2,1‐b]oxazoles has been described by condensation of 2,4(5)‐dinitroimidazole with a series of oxiranes.
The chemistry of 2H‐3,1‐benzoxazine‐2,4(1H)dione (isatoic anhydride). 6. Synthesis of spiro[indoline‐2,2′(1′H)quinazolines]
Authors: Coppola Gary M. , Damon Robert E. 
Published: April 2009

AbstractThe reaction of isatoic anhydrides with potassium cyanide is described. The stoichiometry of the reactants and reaction times dictate the formation of either 2‐imino‐3‐indolinones or spiro[indoline‐2,2′(1′H)quinazolines]. Some spectral data is also discussed.
(E) and (Z)‐α‐hydroxy and α‐methoxyimino‐4‐nitro‐1H‐imidazole‐1‐acetic acids and esters. Spectral properties, conformations and photoisomerization of the new compounds
Authors: Elitropi Guglielmo , Pantò Ezio , Tricerri Silvia 
Published: April 2009

AbstractDetailed experimental procedures are given for the preparation of the stereoisomeric (E)‐ and (Z)‐methyl‐α‐hydroxy and α‐methoxyimino‐4‐nitro‐1H‐imidazole‐1‐acetates and of the related acids. (Z)‐Isomers have been prepared by synthesis. (E)‐Isomers have been obtained only by photoisomerization. Decarboxylation of the acids left the corresponding aldehydes which are ideal compounds for structural studies and configurational assignments.
Condensed pyridazines. Part IV. Reductive cyclization of (Z)‐methyl 3‐(6‐azido‐3‐chloro‐1‐methyl‐4‐oxo‐1,4‐dihydropyridazin‐5‐yl)‐2‐rnethylacrylatc (I) to pyrido[2,3‐c] pyridazines and the acid‐catalysed cyclization of I to a pyrano[2,3‐d] pyridazine
Authors: Maeba Isamu , Mori Kazumi , Castle Raymond N. 
Published: April 2009

AbstractReduction followed by cyclization of (Z)‐methyl 3‐(6‐azido‐3‐chloro‐1‐methyl‐4‐oxo‐1,4‐dihydropyridazin‐5‐yl)‐2‐methylacrylate (I) to pyrido[2,3‐c]pyridazines by treatment with triethyl phosphite or hydrazine hydrate as the reducing agents is described. Compound I was also reductively cyclized with sodium borohydride. Treatment of I with concentrated sulfuric acid gave 8‐chloro‐3,6‐dimethyl‐2,5‐dioxo‐5,6‐dihydro‐2H‐pyrano[2,3‐d] pyridazine (VII) which also could be synthesized by another independent route. A mechanism for the cyclization is proposed.
2‐(Methylpyridyl or quinolyl)benz‐X‐azoles, salts and polymethine dyes
Authors: Barni Ermanno , Savarino Piero 
Published: April 2009

Abstract2‐(Methylpyridyl or quinolyl)benz‐X‐azoles were synthesized by the general reaction between carboxylic acids and o‐bifunctional compounds. By reaction of the bases with methyl iodide, a series of salts were recovered which were identified and when possible transformed into the corresponding polymethine dyes. The main spectroscopic features of these compounds are briefly discussed.
Quaternary salts from 2‐(methylpyridyl or quinolyl)benzimidazoles and related polymethine dyes
Authors: Barni Ermanno , Savarino Piero 
Published: April 2009

AbstractThe quaternisation of 2‐(methylpyridyl or quinolyl)benzimidazoles with methyl iodide leads to a variety of salts depending on the relative position of the nuclei and on the experimental conditions: N‐methylpyridinium, N‐methylquinolinium, methyl and 1,3‐dimethylbenzimidazolium iodides, and hydroiodides were isolated. Cyanine dyes were prepared from N‐methylpyridinium and N‐methylquinolinium methiodides. The main spectrospcopic features of these compounds are briefly discussed.
Synthesis of peptides containing 1,2,3,4‐tetrahydroquinoline‐2‐carboxylic acid. Part 3. Cyclization of dipeptides and amides with acetic anhydride
Authors: Zecchini Giampiero Pagani , Paradisi Mario Paglialunga 
Published: April 2009

AbstractTreatment of protected dipeptides containing 1,2,3,4‐tetrahydroquinoline‐2‐carboxylic acid with acetic anhydride affords only 1H,3H,5H‐oxazolo[3,4‐a]quinolin‐3‐one derivatives. The formation of a‐acylaminomethylketones, arising from the competitive Dakin‐West reaction, was generally observed when the cyclization procedure was extended to some amides of the cyclic imino acid. The preferential stabilization of one of two probable mesoionic intermediates seems to determine the preferred pathway.
Synthesis of schiff bases derived from 2,4,6‐trimethoxypyrimidine‐5‐carboxaldehyde
Authors: Delia Thomas J. , Wilcox Thomas M. , Otteman Ronald R. 
Published: April 2009

AbstractSchiff bases have been formed with methyl‐, methoxy‐, nitro‐ and unsubstituted anilines and 2,4,6‐trimethoxypyrimidine‐5‐earboxaldehyde.
A new synthesis of dibenzo[b,g][1,5]naphthyridine‐6,12(5H,1H)dione (epindolidione)
Authors: Kim C. K. , Maggiulli C. A. 
Published: April 2009

AbstractA new convenient synthesis of dibenzo[b,g][1,5]naphthyridine‐6,12(5H,11H)dione starting from N‐phenylglycine ethyl ester is described. Ester condensation of N‐phenylglycine ethyl ester with diethyl oxalate followed by reaction with aniline under acid catalysis gave a mixture of diethyl dianilinomaleate and diethyl dianilinofumarate in 54% yield. Upon heating this mixture in a high‐boiling inert solvent, 3‐anilino‐2‐ethoxycarbonyl‐4‐quinolone was obtained in 72% yield. Final ring closure of the quinolone derivative using polyphosphoric acid gave the epindolidione.
The dehydrogenation of the alleged hexahydro‐1,2,4‐triazine‐3,6‐dione
Authors: Schwan Thomas J. , Sanford Timothy J. 
Published: April 2009

AbstractThe dehydrogenation of the alleged hexahydro‐1,2,4‐triazine‐3,6‐dione, recently reassigned the 3‐amino‐2,4‐imidazolidinedione structure, gives upon reaction with bromine water or sodium hypobromite bis[3‐(2,4‐dioxoimidazolidinyl)]diazene instead of tetrahydro‐1,2,4‐triazine‐3,6‐dione as reported previously in the literature.
Acyclopyrimidine C‐nucleosides. Synthesis of acyclopseudoisocytidine and its derivatives
Authors: Chu Chung K. 
Published: April 2009

AbstractAcyclopseudouridine (IV), acyclopseudoisocytidine (VII), and their 1‐methyl derivatives (V and VIII) were synthesized from 5‐hydroxymethyluracil (I). Acyclopseudouridine (IV) was conveniently prepared from the condensation of 5‐hydroxymethyluracil (I) with ethylene glycol under acidic condition. Compound IV also could be prepared from 5‐chloromethyluracil, however, this procedure was found to be inferior to the direct condensation method. Methylation of IV with dimethylformamide dimethyl acetal gave 1,3‐dimethylacyclopseudouridine (VI) which was subsequently converted to acyclopseudoisocytidine (VII). 1‐Methyl derivatives V and VIII were obtained from the selective methylation of IV and VII, respectively. 5‐Hydroxymethyluracil also reacted with 2‐mercaptoethanol to give the sulfide derivative (IX).
Synthèse d'arylhydroxyspirocétals. Influence du groupe aryle sur la photocyclisation d'arylcétoacétals en série hétérocyclique et osidique
Authors: Bron Pascale , Cottier Louis , Descotes Gérard 
Published: April 2009

AbstractLa photocyclisation d'arylcétoacétals tétrahydropyranniques conduit selon une réaction de type Norrish II à des composés spiranniques. En série acétalique dihydropyrannique, cette réaction entre en compétition avec la réaction de Paterno‐Buchi. En série osidique, la réaction n'est plus stéréosélective comme dans le cas de dérivés méthylés précédemment étudiés; cependant, l'abaissement de la température ralentit Pinterconversion du radical cétalique et conduit principalement aux produits d'hétérocyclisation avec rétention de configuration. Par ailleurs, l'épimérisation acide des spiro C‐1 sucres donne les dérivés trans α ou β.
The stereochemistry of 4‐methyl‐6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,2,6‐dioxathiazocine 2‐oxides using NMR
Authors: Nishiyama Tomihiro , Kushiyama Masataka , Ikemoto Etsuo , Yamada Fukiko 
Published: April 2009

AbstractTwo isomeric 4‐methyl‐6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,2,6‐dioxathiazocine 2‐oxides were prepared, and their pmr and cmr spectra were examined. From the aromatic solvent shielding values and the magnitudes of the γ shifts, the title compounds are found to exist in the trans and cis forms in solution.
bis‐alkylsulfonylpyridines
Authors: Woods S. G. , Matyas B. T. , Vinogradoff A. P. , Tong Y. C. 
Published: April 2009

AbstractDihalogenated pyridines, some activated with carboxylic, ester or cyano group, were allowed to react with sodium alkylmercaptides. After hydrolysis of the ester or cyano group followed by decarboxylation, bis‐alkylthiopyridines with substituents at 2,3‐, 2,4‐, 2,5‐, 2,6‐ and 3,5‐positions were prepared. These compounds were oxidized to bis‐alkylsulfonylpyridines.