bluuebunny/crossref_metadata_2025_split huggingface dataset:
Convenient synthesis of fused heterocycles from α‐ketohydroximoyl chlorides and heterocyclic amines
Authors: PÁrkÁnyi Cyril , Abdelhamid Abdou O. , Cheng John C. S. , Shawali Ahmad S. 
Published: April 2009

AbstractNitroso derivatives of imidazo[1,2‐a]pyridine (11, 13, 14), imidazo[1,2‐a]pyrimidine (15), imidazo[1,2‐a]pyrazine (16), imidazo[1,2‐b]pyrazole (17), and imidazo[1,2‐b]‐1,2,4‐triazole (19) were obtained in good yields from α‐ketohydroximoyl chlorides3and 2‐aminopyridines (4–6), 2‐aminopyrimidine (7), 2‐aminopyrazine (8), 5‐amino‐3‐phenylpyrazole (9), and 3‐amino‐2H‐1,2,4‐triazole (10), respectively. Under different conditions, the reaction of3with 3‐amino‐2H‐1,2,4‐triazole (10) and 2‐aminopyrazine (8) afforded the noncyclized substitution products18and22, respectively. The structures of the products were assigned and confirmed on the basis of their elemental analyses, spectral data, and alternate synthesis wherever possible.
Analogues du nor‐B benzomorphane. I. Synthese des méthano‐3,5 tétrahydro‐2,3,4,5 1H‐benzazépines et dérivés
Authors: Escale Roger , El Khayat Ammar , Vidal Jean‐Pierre , Girard Jean‐Pierre , Rossi Jean‐Claude 
Published: April 2009

AbstractDe nouveaux édifices homologues du nor‐B benzomorphane, les méthano‐3,5 tétrahydro‐2,3,4,5 1H‐benzazépines‐1 et 2 sont synthétisés en vue de leur étude au niveau du système nerveux central. Les dérivés nitrés et aminés correspondant aux positions 7 et 8 sont obtenus par nitration et réduction sélective.
The crystal structure of 1‐(Piperidin‐1‐yl)‐4‐t‐butyl‐7‐thiabicyclo[4.2.0]‐octane 7,7‐Dioxide [1α,4α,6α]
Authors: BrÚckner S. , Ganazzoli F. , Fatutta S. , Pitacco G. , Valentin E. 
Published: April 2009

AbstractThe crystal structure of the title compound is described.
Synthesis of novel imidazo[1,2‐a][3,1]benzothiazines 4, imidazo[1,2‐a]‐[1,2,4]benzotriazines 5, and 4H‐imidazo[2,3‐c]pyrido[2,3‐e][1,4]oxazines 6
Authors: Gauthier Jean , Duceppe Jean Simon 
Published: April 2009

AbstractStarting from the readily available 2‐aminobenzhydrols (7), 3‐amino‐1,2,4‐benzotriazine (11) and 2‐amino‐3‐pyridinol (12), novel derivatives of 5‐phenyl‐5H‐imidazo[1,2‐a][3,1]benzothiazine‐2‐carboxylic acid, ethyl ester (4), imidazo[2,1‐c][1,2,4]benzotriazine‐2‐carboxylic acid, ethyl ester (5) and 4H‐imidazo[2,3‐c]pyrido‐[2,3‐e][1,4]oxazine (6) were prepared.
The mass spectra of some bis[5‐(2‐mercapto‐1,3,4‐thiadiazolyl)]methyl and aryl derivatives
Authors: Pappalardo Sebastiano , Bottino Francesco , Di Grazia Michele 
Published: April 2009

AbstractThe general fragmentation patterns of five selected title compounds are described. The most significant mass spectral features arise from the interaction of aryl substituents with the adjacent heterocyclic ring. The decomposition of the compounds bearing an ortho nitro group in the S‐aryl moieties is strongly affected by a prominent “ortho effect”.
N‐acylation of 1,3‐dimethyl‐6‐aminouracils. A reversal in the regiospecificity of an electrophilic substitution induced by an intramolecular proton‐transfer
Authors: Bernier Jean‐Luc , HÉnichart Jean‐Pierre , Warin Vincent 
Published: April 2009

AbstractElectrophilic reactions of 1,3‐dimethyl‐6‐aminouracil lead to 5‐substituted derivatives. The introduction of a dialkylaminoalkylamino chain in the 6‐position of 1,3‐dimethyluracil modifies the regiospecificity of the acylation reaction to give N‐6 acylated compounds. This reversal in acylation is induced by an intramolecular proton‐transfer which introduces a change in the electron density of the enamine system. The cyclic transition state and the spatial conformation of the final products substantiate the proposed mechanism, on the basis of X‐ray and 1H nmr data.
N‐quaternary compounds. Part LIX. Facile synthesis of 3‐vinyl‐4(3H)‐pyrimidinethiones
Authors: Pedersen Ansgar Heim , Undheim Kjell 
Published: April 2009

Abstract3‐Vinyl derivatives of 4(3H)‐pyrimidinethiones have been prepared from 2,3‐dihydrothiazolo[3,2‐c]pyrimidinium derivatives through ring‐opening by a strong base such as potassium t‐butoxide in DMF. The pyrimidinium derivative is initially prepared from 4(3H)‐pyrimidinethiones. 3‐Vinyl‐4(3H)‐pyrimidinethiones are also formed by the ready decarboxylation of 2,3‐dihydrothiazolo[3,2‐c]pyrimidinium‐3‐carboxylates. In the mass spectrometer the nature of the volatile species was elucidated by means of appearance potentials and fragmentation patterns.
The synthesis of 1‐substituted 6‐amino‐1H‐pyrrolo‐[3,2‐c]pyridin‐4(5H)‐ones
Authors: Schneller Stewart W. , Luo Jiann‐Kuan , Hosmane Ramachandra S. , DÚrrfeld Rainer H. 
Published: April 2009

AbstractThe synthesis of 1‐methyl‐ (1a) and 1‐benzyl‐6‐amino‐1H‐pyrrolo[3,2‐c]pyridin‐4(5H)‐one (1b) from the appropriate N‐alkylaminoacetaldehyde is described. These provide examples of a synthetic procedure that can be used to prepare 1‐substituted 6‐amino‐1H‐pyrrolo[3,2‐c]pyridin‐4(5H)‐ones wherein the N‐1 substituent is regiospecifically placed.
Synthesis of 5‐amino‐1,3‐dimethylpyrazol‐4‐yl aryl ketones
Authors: Dewald H. A. 
Published: April 2009

AbstractA convenient preparation of 5‐amino‐1,3‐dialkylpyrazol‐4‐yl heterocyclic ketones is reported. They are prepared from the reaction of heterocyclic esters with the di‐lithio derivative from N‐(4‐bromo‐1,3‐dimethyl‐1H‐pyrazol‐5‐yl)benzamide (1).
Reaction of glyceraldehyde with aryl and alkyl chloroformates
Authors: Podraza Kenneth F. 
Published: April 2009

AbstractA number of 2,5‐bis(aryl‐ and alkyloxycarbonyloxymethylene)‐3,6‐bis(aryl‐ and alkoxycarbonyloxy)‐1,4‐dioxanes 5a‐d have been prepared by the reaction of glyceraldehyde with aryl and alkyl chloroformates. Bis aryl carbonates were also formed under certain conditions in this reaction. Nuclear magnetic resonance analysis of 5c indicated that it existed in a chair conformation with all the substituents in an equatorial position.
A novel synthesis for quinoline derivatives
Authors: Fahmy A. M. , Badr M. Z. A. , Mohamed Y. S. , Abdel‐Latif F. F. 
Published: April 2009

AbstractCondensation of ethyl 2‐(2‐oxo‐2,3‐dihydro‐1H‐indolid‐3‐ene)cyanoacetate and/or 2‐(2‐oxo‐2,3‐dihydro‐1H‐indolid‐2‐ene)malononitrile with 3‐methylpyrazolin‐5‐one, 1‐phenyl‐3‐methyl‐pyrazolin‐5‐one, benzoyl acetonitrile or ethyl acetoacetate affords different substituted quinolines. The reaction is suggested to proceed through a nucleophilic addition followed by ring opening and recyclization steps.
Nucleophilic substitution of halopyridines by benzenethiolate anion via a radical chain mechanism
Authors: Kondo Shuji , Nakanishi Minoru , Tsuda Kazuichi 
Published: April 2009

Abstract2‐Halopyridines 1a‐d reacted with sodium thiophenoxide in DMF at 80° to afford the ipso‐substitution products. The following relative order of reactivity was observed: 2‐iodopyridine (1a) ∼ 2‐bromopyridine (1b) ≫ 2‐chloropyridine (1c) ∼ 2‐fluoropyridine (1d). The reaction of 1b is inhibited by the electron scavenger azobenzene and by the radical scavenger benzoqoquinone. Furthermore, results of the reaction of 3‐bromopyridine (2b) serve to rule out pyridyne mechanism. It is reasonable to suggest therefore that the reaction proceeds through the radical chain process containing one electron transfer, that is SRN1.
Activated nitriles in heterocyclic synthesis. The reaction of cinnamonitrile derivatives with active methylene reagents
Authors: Abed Nosrat Mustafa , Hafez Ebtisam Abdel Aziz , Elsakka Ibraheim , Elnagdi Mohamed Hilmy 
Published: April 2009

AbstractThe reaction of substituted cinnamonitrile derivatives with cyanoacetanilide and with ethyl acetoacetate produced several new polyfunctional pyridine and pyran derivatives. Evidence for assigned structure of the reaction products and the possible mechanisms of their formation is presented.
Eight‐membered organosulfur heterocycles. Synthesis of dibenzo[d,g][1,3,6,2]dioxathiaphosphocin and dibenzo[d,g][1,3,6,2]dioxathiasilocin ring systems
Authors: Pastor Stephen D. , Spivack John D. , Steinhuebel Leander P. 
Published: April 2009

AbstractThe reaction of 2,2′‐thiobisphenols with either phenylphosphonous dichloride or phosphorus trichloride followed by an alcohol gave derivatives of the dibenzo[d,g][1,3,6,2]dioxathiaphosphocin ring system. The analogous reaction of 2,2′‐thiobisphenols with alkyl and aryl dichlorosilanes gave the heretofore unreported dibenzo[d,g][1,3,6,2]dioxathiasilocin ring system. The analytical and spectral data are reported.
The insertion and extrusion of heterosulfur bridges. XII. Selectivity and side reactions in the bridging process
Authors: Klemm L. H. , Pou Sovitj , Detlefsen W. D. , Higgins Clay , Lawrence Ross F. 
Published: April 2009

Abstract1‐Phenylnaphthalene undergoes sulfur bridging at 500° in the presence of hydrogen sulfide and a heterogeneous catalyst to produce benzo[b]naphtho[1,2‐d]thiophene (13%). 3‐Methylphenanthrene and 9‐formylphenanthrene diethyl acetal (7b) give sulfur bridging to produce phenanthro[4,5‐bcd]thiophene, i.e. with loss of the ring substituent. Additionally, 7b hydrogenolyzes to 9‐methylphenanthrene. With decadeuteriobiphenyl as a substrate, the dibenzothiophene formed, as well as the biphenyl recovered, is largely devoid of deuterium label. Confirmation that benzene and toluene react under sulfur‐bridging conditions is presented.
The synthesis of 3‐aryl‐6‐alkylpyridazines
Authors: Liang Jason 
Published: April 2009

AbstractNine compounds of general structure R‐X‐Y‐R' where X is a para‐disubstituted phenyl ring and Y is a 3,6‐disubstituted‐pyridazine ring were synthesized. These can be used as liquid crystal dopents. A general procedure for their synthesis was developed. N‐Alkyl benzene and ethyl butyrylacetate were used as starting materials. The purification of reaction intermediates was not necessary if preparative hplc was used to purify the final products. Very pure materials were obtained with good yield. Their structure was confirmed by carbon 13 nmr.
Study of the azide ion reactivity towards heterocyclic cations. V. Syntheses, thermal and photochemical rearrangements of α,α'‐diphenylpyridylazidomethanes
Authors: Desbène P. L. , Jehanno N. 
Published: April 2009

AbstractThe syntheses of α,α'‐diphenylpyridylazidomethanes are reported and the thermal and photochemical rearrangements of these azides are studied. For the thermolysis and photolysis of these azides a step by step mechanism is proposed. The differences between thermolysis and photolysis should come from the nature of the nitrenoide state involved; the 1Δ electrophilic state in thermolysis and the less selective 1σ diradical state in photolysis.
Study of the azide ion reactivity towards heterocyclic cations. VII. Application of thermal and photochemical rearrangements of α,α'‐diphenylpyridylazidomethanes to the syntheses of 4‐pyridyldibenzoheteroazepines
Authors: Desbène P. L. , Jehanno N. 
Published: April 2009

AbstractThe application of thermal and photochemical rearrangements of α,α'‐diphenylpyridylazidomethanes to the synthesis of 4‐pyridyldibenzoheteroazepines is reported. This route provides easily the 11‐(4‐pyridyl)dibenzo[b,f][1,4]oxazepine and the 11‐(4‐pyridyl)dibenzo[b,f][1,4]thiazepine with good yields. In the case of the 11‐(4‐pyridyl)dibenzo[b,f][1,4]selenazepine this route is less interesting because of the instability of this compound. The previously proposed mechanisms for the thermal and photochemical rearrangements of α,α'‐diphenylazidomethanes can be applied to the azides examined.
Synthesis of the 5H‐pyrrolo[2,1‐a]isoindole ring with 1,3‐dipolar cycloaddition reactions
Authors: New J. S. , Yevich J. P. 
Published: April 2009

AbstractThe 1,3‐dipolar cycloaddition reaction between mesoionic oxazolines, formed from either 1,3‐dihydro‐2‐substituted‐2H‐isoindole‐1‐carboxylic acids or 1,3‐dihydro‐1‐oxo‐α‐substituted‐2H‐isoindole‐2‐acetic acids, and dimethylacetylene dicarboxylate has led to the synthesis of several 5H‐pyrrolo[2,1‐a]isoindole derivatives 9a‐d.
Thiazolopyridine analogs of nalidixic acid. 2. Thiazolo[4,5‐b]pyridines
Authors: Leysen D. C. , Haemers A. , Bollaert W. 
Published: April 2009

AbstractA series of 2‐substituted 4‐ethyl‐4,7‐dihydro‐7‐oxothiazolo[4,5‐b]pyridine‐6‐carboxylic acids were synthesized. Antibacterial activity was tested in vitro. None of the new compounds prepared showed any interesting antibacterial activity in vitro against the strains tested.
Reactions of alkali metal derivatives of some heterocyclic amines
Authors: Hough T. L. , Jones G. P. 
Published: April 2009

AbstractProcedures are described for converting 2‐amino‐1,3,4‐oxa‐ and thiadiazoles into various products in one‐pot syntheses. The preparative method employs alkali metal derivatives of the heterocyclic amines as the reactive species.
Etude dans la série des pyrrolidinones: Réaction de mannich du glutamate de diéthyle
Authors: Rigo B. , Fossaert E. , De Quilacq J. , Kolocouris N. 
Published: April 2009

AbstractLes esters N‐arylméthyl pyroglutamiques et leurs dérivés possèdent des propriétés pharmaceutiques intéressantes; leur formation par réaction de Mannich a été étudiée. Le réactif de départ de ces réactions doit ětre le glutamate de diéthyle car des dérivés cyclisés comme le pyroglutamate de méthyle ou le N‐méthylol pyroglutamate de méthyle ne semblent pas réagir.
1,3‐Dipolar cycloaddition reactions of 2‐phenyl‐4‐arylidene‐5(4H)‐oxazolones with nitrile oxides
Authors: Argyropoulos N. G. , Coutouli‐Argyropoulou E. 
Published: April 2009

AbstractStable nitrile oxides are added stereospecifically and regioselectively to the carboncarbon double bond of 2‐phenyl‐4‐arylidene‐5(4H)‐oxazolones resulting spiro‐derivatives 3, 5. The spectral properties of the reaction products are discussed. The cycloadducts give several substituted isoxazolines via an opening of the oxazolone ring with nucleophilic reagents.
The synthesis of 1H‐benzimidazole derivatives containing a 9H‐xanthene or 9H‐thioxanthene ring
Authors: Okabayashi Ichizo , Fujiwara Hidetoshi 
Published: April 2009

Abstract2‐(9H‐Xanthen‐9‐ylmethyl)‐1H‐benzimidazole (2a) was prepared by condensing 9H‐xanthene‐9‐acetic acid (1a) with 1,2‐benzenediamine. Similarly, 2‐(9H‐thioxanthen‐9‐ylmethyl)‐1H‐benzimidazole (2b) and its S,S‐dioxide (2d) were obtained. Compound 2d was also prepared by oxidizing 2b with hydrogen peroxide in acetic acid. Heating of 9H‐thioxanthene‐9‐acetic acid 10‐oxide (1c) with 1,2‐benzenediamine gave 9‐methylene‐9H‐thioxanthene (3). 2‐(9H‐Thioxanthen‐9‐ylmethyl)‐1H‐benzimidazole S‐oxide (2c) was obtained by oxidizing 2b with m‐chloroperbenzoic acid in acetone.
Reaction of 2‐dimethylaminomethylene‐1,3‐diones with Dinucleophiles. IV. Synthesis of 5,7‐dihydrothiopyrano[3,4‐c]pyrazol‐4(1H)‐ones, 5H‐Thiopyrano[4,3‐d]isoxazol‐4(7H)‐one and 6H‐Thiopyrano[3,4‐d]pyrimidin‐5(8H)‐ones
Authors: Menozzi Giulia , Mosti Luisa , Schenone Pietro 
Published: April 2009

AbstractThe reaction of 2H‐thiopyran‐3,5(4H,6H)‐dione with N,N‐dimethylformamide dimethyl acetal gave in good yield 4‐dimethylaminomethylene‐2H‐thiopyran‐3,5(4H,6H)dione (II), which afforded 1‐substituted 5,7‐dihydrothiopyrano[3,4‐c]pyrazol‐4(1H)‐ones with aliphatic and aromatic hydrazines, 5H‐thiopyrano[4,3‐d]isoxazol‐4(7H)‐one (IV) with hydroxylamine hydrochloride and 2‐substituted 6H‐thiopyrano[3,4‐d]pyrimidin‐5(8H)‐ones with amidines and guanidines, generally in satisfactory yields. 4‐(t‐Butylhydrazonoformyl)‐2H‐thiopyran‐3,5(4H,6H)‐dione was isolated as an intermediate in the reaction of II with t‐butylhydrazine, whereas formamidine gave with II 4‐iminoformyl‐2H‐thiopyran‐3,5(4H,6H)‐dione as the sole product. The isoxazole IV isomerized easily with sodium methoxide to 3,4,5,6‐tetrahydro‐5,5‐dihydroxy‐3‐oxo‐2H‐thiopyrano‐4‐carbonitrile.
Reaction of sulfene and dichloroketene with N,N‐disubstituted α‐aminomethyleneketones. Synthesis of 5H‐pyrano[3,4‐e]‐1,2‐oxathiin and 2H,5H‐Pyrano[4,3‐b]pyran derivatives
Authors: Menozzi Giulia , Mosti Luisa , Schenone Pietro 
Published: April 2009

AbstractThe polar 1,4‐cycloaddition of sulfene to N,N‐disubstituted (E)‐3‐aminomethylene‐2,3,5,6‐tetrahydro‐4H‐pyran‐4‐ones II, prepared from 2,3,5,6‐tetrahydro‐4H‐pyran‐4‐one via the 3‐hydroxymethylene derivative, occurred only in the case of aliphatic N‐substitution to give, generally in satisfactory yield, 4‐dialkylamino‐3,4,7,8‐tetrahydro‐5H‐pyrano[3,4‐e]‐1,2‐oxathiin 2,2‐dioxides, which are derivatives of the new heterocyclic system 5H‐pyrano[3,4‐e]‐1,2‐oxathiin. The cycloaddition of dichloroketene to II occurred only in two cases of aromatic N‐substitution to give 3,3‐dichloro‐3,4,7,8‐tetrahydro‐4‐(methylphenyl)(diphenyl)amino‐2H,5H‐pyrano[4,3‐b]pyran‐2‐ones IVi,l. Dehydrochlorination of IV with triethylamine was successful only in the case of IVl to give 3‐chloro‐7,8‐dihydro‐4‐diphenylamino‐2H,5H‐pyrano[4,3‐b]pyran‐2‐one in low yield.
The reactions of arylamines with chelidonic acid
Authors: Katritzky Alan R. , Murugan Ramiah , Sakizadeh Kumars 
Published: April 2009

AbstractDepending on the conditions, and the basicity of the amine, arylamines react with chelidonic acid to yield five different types of product: salts, N‐arylchelidamic acids, N‐aryl‐4‐pyridone‐2‐carboxylic acids, N‐aryl‐4‐pyridones, or chelidamic acid itself.
Zur elektrophilen Substitution des Xanthylium‐Ions an Indolen. Untersuchungen zur Positionsselektivität
Authors: Deschner R. , Pindur U. 
Published: April 2009

AbstractThe indoles 3, 5, 7, 9 and 11 yield xanthenylindoles in the reaction with the SN1‐active reagent xanthydrole (1) by acid catalysis. The regioselectivity of this electrophilic heteroaromatic substitution is predominantly controlled by the acid concentration, by the temperature and by the stoichiometric composition of the reactants. An order of positions which is supported by selectivity on the indole nucleus is presented in the experimental results of this model reaction.
2‐Phenylphthalimidine derivatives. A probable formation mechanism of adducts from 3‐benzylidenephthalide and aniline
Authors: Scartoni Valerio , Tognetti Tiziana 
Published: April 2009

Abstract3‐Benzyl‐3‐hydroxy‐2‐phenylphthalimidine (1) and 3‐anilino‐3‐benzyl‐2‐phenylphthalimidine (2), the unusual adduct, are obtained from the title compounds. 3‐Alkoxy‐3‐benzyl‐2‐phenylphthalimidines 3 are synthesized. The behaviour of 1, 3‐benzylidene‐2‐phenylphthalimidines (4 and 5), 3‐(α‐bromobenzylidene)‐2‐phenylphthalimidines (6 and 7) with respect to bases and the preparation of the open tautomer 13 of 1 and its hydrochloride are described. A hypothetical mechanism about the formation of 1 and 2 is suggested.
Synthesis and antimalarial properties of 2,4‐diamino‐6‐[(aryl)thio, sulfinyl, and sulfonyl]pyrido[3,2‐d]pyrimidines
Authors: Colbry Norman L. , Elslager Edward F. , Werbel Leslie M. 
Published: April 2009

AbstractThe synthesis and antimalarial activity of a series of 2,4‐diamino‐6‐[(aryl)thio, sulfinyl and sulfonyl]pyrido‐[3,2‐d]pyrimidines is described. Nitration of 2,6‐dichloropyridine provided the 3‐nitro derivative which was converted to 6‐chloro‐3‐nitro‐2‐pyridinecarbonitrile (V) with cuprous cyanide. Condensation of an aryl thiol with V gave the 6‐arylthiopyridines VI which were reduced with iron in hydrochloric acid and condensed with chloroformamidine to give the 6‐arylthiopyrido[3,2‐d]pyrimidin‐2,4‐diamines X. Alternatively V was reduced to the amine VIII condensed with chloroformamidine and the resulting 6‐chloropyrido[3,2‐d]pyrimidine (IX) was treated with an arylthiol. Oxidation of X provided sulfinyl and sulfonyl analogs.
Synthèse de benzopyrannopyridines et de dihydrobenzoquinoléines
Authors: Bellassoued‐Fargeau Marie‐Claude , Maitte Pierre 
Published: April 2009

AbstractLa cycloaddition thermique d'un système α‐énone avec l'oxyde de vinyle et d'éthyle conduit à un éthoxy‐2 dihydropyranne aisément transformé en pyridine par action du chlorhydrate d'hydroxylamine. Ce schéma réactionnel a permis de réaliser la synthèse de benzopyrannopyridines et de dihydrobenzoquinoléines.
2H‐1,2,4,6‐thiatriazin‐3(4H)‐one 1‐oxides and their regioselective N4‐methylation and ‐amination
Authors: Nakayama Yoshinori , Sanemitsu Yuzuru 
Published: April 2009

AbstractThe syntheses of 2H‐1,2,4,6‐thiatriazin‐3(4H)‐one 1‐oxides and 1,1‐dioxides is described. The reaction of 1‐carbamoyl‐2‐methylisothioureas 2 with thionyl chloride gave 2H‐1,2,4,6‐thiatriazin‐3(4H)‐one 1‐oxides 3 in high yields. The treatment of 3 with either diazomethane or O‐(2,4‐dinitrophenyl)hydroxylamine furnished regioselectively N4‐methylated and N4‐aminated 2H‐1,2,4,6‐thiatriazin‐3(4H)‐one 1‐oxides, respectively. Subsequent dimethylamination of 4 followed by oxidation with m‐chloroperoxybenzoic acid led to 2H‐1,2,4,6‐thiatriazin‐3(4H)‐one 1,1‐dioxides 6a‐c.
Synthesis of 2‐substituted naphtho[1′,2′:4,5]thiazolo[3,2‐b]‐1,2,4‐triazoles
Authors: Liu Kang‐Chien , Shih Bi‐Jane , Tao Tung‐Mei 
Published: April 2009

AbstractN‐Amination of 2‐aminonaphtho[1,2‐d]thiazole (1) with O‐mesitylenesulfonylhydroxylamine (2) afforded the corresponding 2,3‐diaminonaphthothiazolium salt 3a. Cyclocondensation of 3a or its free base 3b with appropriate carboxylic acid derivatives 4a‐f gave the title compounds 5a‐f in satisfactory yields (54–95%). Structures of the products were assigned on the bases of spectral and elemental analyses.
Syntheses of 11‐hydroxy and 11‐hydroxy‐11‐methyl‐14‐methoxy‐14‐azadispiro[5.1.5.2]pentadec‐9‐ene‐7,15‐diones
Authors: Neelima  , Bhaduri A. P. 
Published: April 2009

AbstractA facile synthesis, which permits regioselective incorporation of hydroxy and/or methyl substituents at position 11 of 14‐methoxy‐14‐azadispiro[5.1.5.2]pentadec‐9‐ene‐7,15‐dione, has been described.
The synthesis of thienocycloheptenoindoles
Authors: Abarca Belén , Ballesteros Rafael , Jones Gurnos 
Published: April 2009

AbstractA synthesis of the methylthieno[3,2‐c]cyclohepteno[b]indole 7 from 2‐methylthieno[3,2‐b]cycloheptanone3is described. Unsuccessful attempts to prepare the isomeric thienocycloheptenoindole system present in formula2, from the dihydrobenzothiophenone8, and from derivatives of 5‐(2‐thienyl)‐4‐oxopentanoic acid,17and18, and fromN‐benzylcycloheptindol‐1‐one22were unsuccessful. The preparation of 4,5‐dihydro‐2‐phenyl‐1‐thienylmethyl‐3H‐pyridazin‐3‐one20and of the 5‐aminopyrazole21are reported.
Heterocyclic studies. 2. 5‐Chloro‐1H‐1,2,3‐triazole‐4‐carboxaldehydes, preparation and rearrangement reactions
Authors: Olesen Preben H. , Nielsen Flemming E. , Pedersen Erik B. , Becher Jan 
Published: April 2009

AbstractA general procedure for synthesis of 5‐chloro‐1H‐1,2,3‐triazole‐4‐carboxaldehydes 4 and the rearrangement reaction of 4‐(N‐substituted)iminomethylene‐1H‐1,2,3‐triazol‐5‐ols 6 into N‐substituted‐1H‐1,2,3‐triazole‐4‐carboxamides 7 are described.
Composés sulfurés hétérocycliques. CII. Action de l'hydroxylamine sur les dihydro‐1,2 benzothiazine‐3,1 thiones‐4
Authors: Legrand Louis , Lozac'h Noël 
Published: April 2009

AbstractL'hydroxylamine réagit sur les alkyl‐1 dihydro‐1,2 benzothiazine‐3,1 thiones‐4 (1) en donnant des alkyl‐1 hydroxy‐3 dihydro‐2,3 1H‐quinazolinethiones‐4 (2). En milieu neutre, le même réactif transforme les aryl‐1 dihydro‐1,2 benzothiazine‐3,1 thiones‐4 (3) en aryl‐1 hydroxyimino‐4 dihydro‐1,4 2H‐benzothiazines‐3,1 (4). En milieu acide, les mêmes produits conduisent aux aryl‐1 hydroxy‐3 dihydro‐2,3 1H‐quinazolinethiones‐4 (5), généralement accompagnées de leurs isomères 4. Les thiones 2 et 5, ainsi que les oximes 4, chauffées à 200°, se décomposent en donnant, en proportions variables, des 1H‐quinazolinethiones‐4 (6) ou (7), des 1H‐quinazolinones‐4 (9) et des dihydro‐2,3 1H‐quinazolinethiones‐4 (11). Les 1H‐quinazolinethiones‐4 (7), par action de l'iodure de méthyle, donnent des iodures de méthylthio‐4 quinazolinium‐1 (12) hydrolysables en 1H‐quinazolinones‐4 (9) qui peuvent aussi être obtenues par action du N‐oxyde de benzonitrile sur les thiones correspondantes. Les aryl‐1 1H‐quinazolinethiones‐4 (7) réagissent aisément sur les nucléophiles XNH2 pour donner divers dérivés de l'imino‐4 dihydro‐1,4 quinazoline. Tandis que par action de l'iodure de méthyle les thiones 7 subissent une S‐méthylation, par action du même réactif, les aryl‐1 1H‐quinazolinones‐4 (9) donnent des iodures d'aryl‐1 méthyl‐3 oxo‐4 dihydro‐3,4 quinazolinium‐1 (18) par N‐méthylation. Les structures proposés ont été confirmées par spectrométries uv et ir, ainsi que par rmn.