bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 2‐carboxy‐4‐methylazetidine. A novel isomeric analog of dl‐proline
Authors: Soriano David S. , Podraza Kenneth F. , Cromwell Norman H. 
Published: March 2009

AbstractL‐Azetidine‐2‐carboxylic acid is a naturally occurring azetidine currently used in the synthesis of abnormally high molecular weight polypeptides. The synthesis of 2‐carboxy‐4‐methylazetidine is now reported which is a novel isomeric analog of dl‐proline. Reaction of α,β‐dibromo carbonyl ester with three molar equivalents of benzylamine yields 1‐benzyl‐2‐carbomethoxy‐4‐methyl‐azetidine. Hydrolysis of the latter compound with barium hydroxide yields 1‐benzyl‐2‐carboxyl‐4‐methylazetidine which, if subjected to catalytic hydrogenation., yields the title compound in practical yield. The cis configuration is tentatively assigned to the title compound on the basis of previously published arguments.
Pyrrolo[1,2‐d]triazines‐1,2,4. I. Dérivés pyrroliques
Authors: Lancelot Jean Charles , Maume Daniel , Robba Max 
Published: March 2009

AbstractLa synthèse d'hydrazides pyrroliques a été effectuée à partir de l'hydrazide de l'acide pyrrole‐carboxylique‐2 et celle d'hydrazones pyrroliques à partir du pyrrole‐carboxaldéhyde‐2. Les pyrrolyl‐2 oxadiazoles et thiadiazoles sont accessibles par cyclisation des hydrazides pyrroliques avec l'oxychlorure et le décasulfure de phosphore. Ces dérivés sont destinés à la synthèse de pyrrolo[1,2‐d]triazines‐1,2,4 par cyclisation ou par réarrangement.
Carbon‐13 nuclear magnetic resonance spectra of substituted‐s‐triazolyl tetrazoles
Authors: Kothari Paresh J. , Stenberg Virgil I. , Singh Shiva P. , Parmar Surendra S. , Zoellner Robert W. 
Published: March 2009

AbstractThe natural abundance carbon‐13 nuclear magnetic resonance spectra of various 5‐aryltetrazoles, 1‐(5‐aryltetrazol‐2‐ylacetyl)‐4‐phenyl thiosemicarbazides and 5‐(5‐aryltetrazol‐2‐ylmethyl)‐4‐phenyl‐s‐triazole‐3‐thiols were recorded using Fourier transform techniques. The chemical shifts of various carbon resonances have been assigned on the basis of chemical shift theory, the signal multiplicity observed in the single‐frequency off‐resonance decoupled (SFORD) spectra and comparison with the chemical shifts of the model compounds.
Oxidative cyclization of morusin
Authors: Nomura Taro , Fukai Toshio , Matsumoto Junko 
Published: March 2009

AbstractOxidative cyclization of morusin (I) by using one‐electron transfer oxidizing agents (manganese dioxide, silver oxide) afforded morusin hydroperoxide (II). A similar reaction was carried out in the presence of 2,4,6‐tri‐t‐butylphenol, a radical quencher, to give compounds (IV, V, VI and VII) coupled with the 2,4,6‐tri‐t‐butylphenoxy radical. On the basis of above results, the possible mechanism of this oxidative cyclization was discussed. In addition, morusin hydroperoxide (II) was also obtained by photo‐sensitized oxidation of morusin (I) in the presence of sensitizers (Rose Bengal, hematoporphyrin). To elucidate the reaction mechanism similar reactions were carried out in the presence of radical quencher (2,4,6‐tri‐t‐butylphenol) or singlet oxygen quencher (triethylenediamine). From these results, the possible mechanism of the formation of morusin hydroperoxide (II) from morusin (I) was discussed.
Heterocycles from substituted amides. VII Oxazoles from 2‐isocyanoacetamides
Authors: Chupp John P. , Leschinsky Kindrick L. 
Published: March 2009

AbstractCertain heretofore unknown tertiary α‐isocyanacetanilides 1 are reported for the first time, prepared by methods necessarily different from those employed to prepare the previously cited aliphatic α‐isocyano‐acetamides 2. Like 2, 1 has been shown to readily undergo dialkylation with alkyl halides. Moreover, 1 also gives rise to oxazole and oxazoline derivatives upon reaction with acyl halides and aldehydes, respectively, resembling the similarly activated α‐isocyano esters and sulfones. Further, in a demonstrable ring‐chain tautomeric equilibration, apparently restricted to tertiary amides, 1 readily cyclizes, providing the only known synthesis of 5‐amino‐2,4‐unsubstituted oxazoles 3. In other examples 4‐chloro and 4‐alkyl‐5‐amino‐oxazoles are produced. The materials and reactions are characterized, and compared with previous related studies.
Heterocycles from substituted amides. VIII Oxazole derivatives from reaction of isocyanates with 2‐isocyanoacetamides
Authors: Chupp John P. , Leschinsky Kindrick L. 
Published: March 2009

AbstractA facile reaction of 2‐isocyanoacetamides 1 with reactive aryl and sulfonyl isocyanates is shown to give 5‐amino‐2‐oxazolecarboxamides 3 in a reaction arising from electrophilic attack of isocyanate with the nucleophilic isocyanide carbon. This reaction, perhaps proceeding through an unstable nitrile ylid intermediate reminiscent of the Cornforth rearrangement, is a first example of ring closure via acylation, involving the activated methylene of an organic isocyanide, without recourse to added base. Isomeric 5‐amino‐4‐oxazolecarboxamides 4 are formed when 5‐aminooxazoles 2 react with isocyanates. Since 2 has previously been shown to easily form by thermal isomerization of 1, methods now exist for the preparation of both 5‐amino‐ 2‐ and 4‐oxazolecarboxamides from the single starting material 1. In contrast, 1 with acyl isocyanates is shown to give a variety of products, including iminooxazolinediones, 5‐amino‐2‐oxazolecarbox‐amide 3 and 2 (1) pyrazinones (tentatively identified), depending on the structure of the isocyanates.
Formation d'hydroxy‐5 méthyl‐5 isoxazolidinones‐3 par action du dicétène sur les hydroxylamines
Authors: Perronnet Jacques , Girault Pierre , Demoute Jean‐Pierre 
Published: March 2009

AbstractL'action du dicétëne sur les hydroxylamines monosubstituées à l'azote conduit à des dérivés cycliques de type hydroxy‐5 méthyl‐5 isoxazolidinone‐3.
Heteroacyl azides as acylating agents for aromatic or heteroaromatic amines
Authors: Stanovnik B. , Tišler M. , Golob V. , Hvala I. , Nikolić O. 
Published: March 2009

AbstractThe possibility of formation of substituted heterocyclic amides from heteroacyl azides and aromatic or heteroaromatic amines was investigated. Although acylation proceeded in some cases under mild reaction conditions, formation of N,N′‐disubstituted ureas was the main process at elevated temperatures.
Syntheses of covalently‐linked porphyrin‐quinone complexes
Authors: Kong Josephine L. Y. , Loach Paul A. 
Published: March 2009

AbstractA synthetic route for the preparation of covalently‐linked porphyrin‐quinone and metalloporphyrin‐quinone complexes as models for the phototrap in bacterial photosynthesis is described. 5‐(4‐Carboxyphenyl)‐10,15,20‐tritolylporphyrin, prepared by a mixed aldehyde approach, was attached to a benzoquinone center with a propanediol bridge by means of ester linkages. The starting point for the benzoquinone moiety was 2,5‐dihydroxyphenylacetic acid, whose hydroquinone function was first protected by preparing its dimethyl ether. The spacing between the two centers of the complex could be altered simply by varying the length of the bridging group (a diol) employed. Boron tribromide was used to unmask the quinol derivatives in the final coupled products. The zinc(II) derivative of porphyrin‐quinone complex was prepared by addition of a saturated solution of zinc acetate in methanol to a solution of the corresponding porphyrin‐hydroquinone complex in dichloromethane at room temperature. The structures of these complexes were confirmed by nmr spectroscopy, uv‐visible absorption, and mass spectroscopy. Oxidation of the quinol moiety in the covalently‐linked complex to its corresponding quinonoid derivative was accomplished by treating a solution of the complex in dichloromethane with a stoichiometric amount of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone, a high potential benzoquinone.
Benzomorphan related compounds. XII 2,5‐Methanothieno[3,2‐g]quinolines as rigid bridged thienomorphans
Authors: Bosch J. , Alvarez M. , Granados R. 
Published: March 2009

AbstractThe preparation of a 1,2,3,4,4a,5,9,9a‐octahydro‐2,5‐methanothieno[3,2‐g]quinoline, which can be considered as a rigid thieno[3,2‐f]morphan system due to an additional two‐atoms bridge between the 3 and 9 positions of the morphan nucleus, is described. The synthetic route involved the acidic cyclization of a 3‐(2‐thenyl)‐2‐azabicyclo[2.2.2]oct‐7‐ene, obtained by the Diels‐Alder reaction between 1,3,4‐trimethyl‐2‐(2‐thenyl)‐1,2‐dihydropyridine and ethyl acrylate.
New practical synthesis of prazosin
Authors: Honkanen Erkki , Pippuri Aino , Kairisalo Pekka , Thaler Heinrich , Koivisto Maija , Tuomi Sirpa 
Published: March 2009

AbstractA new four step synthesis of prazosin, 2‐[4‐(2‐furoyl)piperazin‐l‐yl]‐4‐amino‐6,7‐dimethoxyquinazoline, has been described. The method is also adaptable for the preparation of other substituted 4‐aminoquinazolines. The yields are good in every step and the reactions are performed with ease. Prazosin hydrochloride of high purity is obtained directly in the last step.
Studies on novel heterocyclic ring systems. Reaction of 4‐hydroxylcoumarin with o‐aminobenzaldehyde and 2‐mercaptoaniline
Authors: Tabaković K. , Tabaković I. , Trkovnik M. , Jurić A. , Trinajstić N. 
Published: March 2009

AbstractReactions of 4‐hydroxycoumarin (1) with o‐aminobenzaldehyde (2) and 2‐mercaptoaniline (5) have been investigated. The yet unreported 6,12‐dihydro‐l‐benzopyrano[3,4‐b][1,4]benzothiazin‐6‐one (6) system has been synthesized and characterized on the basis of spectral and analytical data. A novel synthetic route to 6H‐l‐benzopyrano[4,3‐b]quinolin‐6‐one (4) is reported. HMO calculations predict the most reactive sites on the molecules.
Rearrangement of a pyranone to a benzothiazole
Authors: White R. L. , Schwan Thomas J. , Alaimo R. J. 
Published: March 2009

AbstractThe conversion of 2‐chloromethyl‐5‐methoxy‐4H‐pyran‐4‐one to 2‐amino‐5‐hydroxy‐6‐methoxybenzothiazole hydrochloride under mild reaction conditions has been observed. The synthesis of the identical benzothiazole by an alternate unequivocal method is also reported.
3,3‐Dinitrobutyl‐1,2,4‐oxadiazoles
Authors: Bjorklund Mark D. , Coburn Michael D. 
Published: March 2009

AbstractThe syntheses of 3,5‐bis(3,3‐dinitrobutyl)‐1,2,4‐oxadiazole and a series of 3‐aryl‐5‐(3,3‐dinitrobutyl)‐1,2,4‐oxadiazoles were accomplished by treating 4,4‐dinitropentanoyl chloride with the appropriate amidoximes to yield the intermediate O‐(4,4‐dinitropentanoyl)amidoximes, which were dehydrated to the 1,2,4‐oxadiazoles.
Nouvelle synthése de dioxènes‐1,4
Authors: Bacquet Cathy , Einhorn Jacques , Lelandais Daniel 
Published: March 2009

AbstractNous décrivons la synthèse de quelques dioxénes‐1,4 connus ou nouveaux à partir des methoxy‐2 dioxannes‐1,4 correspondants obtenus par voie électrochimique.
5‐Amino‐4,5‐dihydroisoxazoles. Part II . Reactions of 5‐amino‐3‐aryl‐4‐methylene‐4,5‐dihydroisoxazoles with Nucleophiles
Authors: Pocar Donato , Rossi Luisa Maria , Scorca Franca , Trimarco Pasqualina 
Published: March 2009

AbstractSeveral 5‐amino‐3‐aryl‐4‐methylene‐4,5‐dihydroisoxazoles were reacted with methoxide, benzenethiolate, benzenethiol, carboxylic acids and secondary amines. Addition and/or addition‐elimination products were obtained. Reaction mechanisms are discussed.
An HMO study of the azo‐hydrazone tautomerism in diazonium coupling products of 5‐isoxazolones
Authors: Párkányi Cyril , Shawali Ahmad S. 
Published: March 2009

AbstractThe HMO method has been used to study tautomerism in 3‐substituted 4‐arylazo‐5‐isoxazolones (2), the possible tautomeric structures being 2a‐2d. Also the common anions of these tautomers, 6, have been theoretically studied. In addition to the free molecules, HMO calculations have been carried out for structures with hydrogen bonds to protic solvents, for tautomers with intramolecular hydrogen bonds, and for dimers formed via intermolecular hydrogen bonds. In all these situations, the hydrazone form 2a has been shown to be most stable. Also the inductive effect of electron‐donating and electron‐withdrawing substituents in the arylazo moiety upon the stability of various tautomers has been investigated. The results obtained on the basis of HMO calculations are in full agreement with the experimental data of Summers and co‐workers. Several m‐ and p‐substituted 4‐arylazo‐3‐methyl‐5‐isoxazolones have been synthesized and their spectral data and melting points reported.
[1]Benzothienopyrimidines. I. Etude de la 3H‐benzothieno[3,2‐d]pyrimidone‐4
Authors: Robba Max , Touzot Paulette , ‐El‐Kashef Hussein 
Published: March 2009

AbstractLa 3H‐benzothiéno[3,2‐d]pyrimidone‐4 (3) a été synthétisée par cyclisation bimoléculaire de l'amino‐3 carbéthoxy‐2 benzothiophéne (1) avec le formamide. Les réactions électrophiles effectuées sur la benzo‐thiénopyrimidone (3) conduisent à des dérivés de substitution sur l'azote lactamique dont la structure a été prouvée par 1H rmn et au moyen de synthèses univoques. La benzothiéno[3,2‐d]pyrimidone (3) permet d'accéder à la benzothiéno[3,2‐d]pyrimidine (7) soil par l'intermédiaire de la 3H‐benzothiéno[3,2‐d]‐pyrimidinethione‐4 (6), soit par l'intermédiaire de la chloro‐4 benzothiéno[3,2‐d]pyrimidine (4) et de l'hydrazino‐4 benzothiéno[3,2‐d]pyrimidine (5).
Benzomorphan related compounds. XIII. Syntheses of 2,6‐methanopyrrolo[1,2‐d] [1,4]diazocines
Authors: Bosch J. , Mauleón D. , Granados R. 
Published: March 2009

AbstractTwo alternative syntheses of 2,6‐methanopyrrolo[1,2‐d][1,4]diazocines (I) based in the acidic cyclization of 2‐(1‐pyrrolylmethyl)tetrahydropyridines are described. In the first synthetic route, lithium aluminum hydride reduction of 2‐cyano‐1,4‐dimethyl‐1,2,3,6‐tetrahydropyridine (IIa) followed by reaction of the resulting primary amine with 2,5‐diethoxytetrahydrofuran affords the requisite tetrahydropyridine IVa. An analogous sequence from 2‐cyano‐4,6‐di‐methylpyridine (V) leads to the corresponding 2‐(1‐pyrrolylmethyl)pyridine VII which by quaternization and borohydride reduction yields a mixture of isomeric tetrahydropyridines, precursors of the pyrrolodiazocine systems Ib and Ic. Structural and stereochemical assignment of the synthesized compounds are discussed.
New heterocyclic systems. Benzo[4,5]cyclohepta[1,2‐b]pyrrole and benzo[5,6]cyclohepta[1,2‐f]pyrrolizidine derivatives
Authors: Ackrell J. , Franco F. , Guzmàn R. Greenhouse A. , Muchowski J. M. 
Published: March 2009

AbstractThe synthesis of the polycyclic pyrrole acetic acids 9e, 13e and 13g by multistep processes from 1‐bromo‐4‐phenylbutan‐2‐one (6c) is reported. An instance of the use of the 2‐chloroethyl moiety as a pyrrole nitrogen protecting group is described. The α‐methylaminoketone (6e) was synthesised by a novel two step process from 6c and methyl N‐methylformimidate (12).
Diels‐alder reaction of 2‐chloro‐2‐nitrosopropane with 1,3‐cyclohexadiene
Authors: Kesler Ewa 
Published: March 2009

Abstract3‐(2‐Chloropropyl)‐2‐oxa‐3‐azabicyclo[2.2.2]oct‐5‐ene and 2‐oxa‐3‐azabicyclo[2.2.2]oct‐5‐ene hydrochloride have been prepared by cycloaddition of 2‐chloro‐2‐nitrosopropane to 1,3‐cyclohexadiene and their structure determined by nmr, using a 1H nmr shift reagent.
Reaction of N‐cyanoformimidates with some heterocyclic compounds. A new synthesis of 5‐azaadenine and related compounds
Authors: Lalezari I. , Nabahi S. 
Published: March 2009

Abstract3‐Amino‐1,2,4‐triazoles and 2‐aminobenzimidazole were reacted with N‐cyanoimidates to give 5‐amino‐1,2,4‐triazolo[2,3‐a]‐1,3,5‐triazines (5‐azaadenines) and 4‐aminobenzimidazo[1,2‐a]‐1,3,5‐triazines, respectively. The structures of the compounds obtained were confirmed through the comparison with some of the possible isomers prepared by independant methods.
Synthesis of a 4‐hydroxyisoquinolin‐1‐one and a related dibenzo[α,g]quinolizin‐8‐one
Authors: Coyle J. D. , Challiner J. F. , Haws E. J. , Newport G. L. 
Published: March 2009

AbstractAqueous acid converts the imidazo[4,3‐α]isoindol‐5‐one 2 to a 4‐hydroxyisoquinolin‐1‐one (3). A related imidazoisoindolone 6, obtained by photochemical cyclization of the Mannich base from 1,2,3,4‐tetrahydro‐isoquinoline, formaldehyde and phthalimide, gives a dibenzo[a,g]quinolizin‐8‐one (7) in a similar reaction.
Chemistry of the phenoxathiins and isosterically related heterocycles. XII. Synthesis of diazaphenoxathiin analogs: 1,9‐Diazaphenoxathiin and 1,7‐diazaphenoxathiin
Authors: Caldwell Steven R. , Turley James C. , Martin Gary E. 
Published: March 2009

AbstractThe synthesis of the first diazaphenoxathiins, 1,9‐diazaphenoxathiin and 1,7‐diazaphenoxathiin, are described. Complete assignments are made for the 13C‐nmr spectra of these compounds based on additivity correlation and 1H‐13C spin‐coupling constants. The isolation and confirmation of the structure of 2‐[2′(‐3′‐nitropyridylthio)]‐3‐[2″‐(3″‐nitropyridyloxy)] pyridine using 13C‐nmr and appropriate model compounds is also discussed. A preliminary evaluation of spontaneous motor depression in mice showed a substantial difference between the observed activities of the two diazaphenoxathiins reported. The possibility of the observed difference being associated with the relative positions of the annular aza‐substitutions is discussed.
Confirmation of the structure of the bicyclic oxidation product of dehydroascorbic acid bis‐phenylhydrazone
Authors: El Khadem Hassan S. , El Ashry El Sayed H. , Jaeger David L. , Kreishman George P. , Foltz Rodger L. 
Published: March 2009

AbstractThe structure of the bicyclic oxidation product of dehydro L‐ascorbic acid has been confirmed by detailed mass spectroscopy and 13C nmr spectroscopy as 3. This structure was put in doubt, when electron ionization mass spectroscopy detected a molecular peak two mass units higher than expected. Careful experiments at low temperature revealed that the molecular ion disproportionates when heated, giving ion 2 or one of its isomers.
Hydrazidoyl halides in synthesis of Δ2‐1,3,4‐selenadiazolin‐5‐ones
Authors: Hassaneen Hamdi M. , Shetta Abdelfattah , Shawali Ahmad S. 
Published: March 2009

AbstractReaction of hydrazidoyl halides 1‐5 with potassium selenocyanate in ethanol produces the corresponding 2,4‐disubstituted‐5‐iminoδ2‐1,3,4‐selenadiazolines, 9‐13 respectively. Nitrosation of the latter yields the N‐nitroso derivatives 14‐17, which decompose upon refluxing in xylene to give 2,4‐disubstituted Δ2‐1,3,4‐selenadiazolin‐5‐ones in good yield. Compounds 9‐13 give the respective N‐acetyl derivatives 22‐26 and N‐benzoyl derivatives 27‐31 with acetic anhydride and benzoyl chloride in pyridine.
Synthesis of 4‐amino[1] benzofuro[3,2‐g] cinnolines
Authors: Ladurée D. , Florentin D. , Robba M. 
Published: March 2009

AbstractThe synthesis of the new heterocycles, 4‐amino[1]benzofuro[3,2‐g]cinnolines, was accomplished by the intramolecular cyclization of the Z‐configuration of cyanoarylhydrazones. The latter compounds were obtained via interaction between the diazonium salt of 3‐amino‐dibenzofuran and various active methylene compounds via the Japp‐Klingemann reaction. The alkaline treatment of azo intermediates 4, which may be isolated in the course of condensation, gave the corresponding cyanoarylhydrazones 5. A study of the configuration and possible isomerisations is reported.
Reaction of sulfene and dichloroketene with open‐chain N,N‐disubstituted α‐aminomethyleneketones. Synthesis of N,N‐disubstituted 4‐amino‐3,4‐dihydro‐(5‐methyl‐6‐phenyl)(5,6‐diphenyl)‐1,2‐oxathiin 2,2‐dioxides and of 4‐amino‐3‐chloro‐5‐methyl‐6‐phenyl‐2H‐pyran‐2‐ones
Authors: Bargagna Alberto , Schenone Pietro , Bondavalli Francesco , Longobardi Mario 
Published: March 2009

AbstractCycloaddition of sulfene to N,N‐disubstituted 3‐amino‐2‐methyl‐1‐phenyl‐2‐propen‐1‐ones (I) and 3‐amino‐1,2‐diphenyl‐2‐propen‐1‐ones (II) occurred in good to moderate yield only in the case of aliphatic N‐substitution to give 4‐dialkylamino‐3,4‐dihydro‐(5‐methyl‐6‐phenyl)(5,6‐diphenyl)‐1,2‐oxathiin 2,2‐dioxides. Polar 1,4‐cycloaddition of dichloroketene to I and II occurred only in the former case, giving in good to moderate yield N,N‐disubstituted 4‐amino‐3,3‐dichloro‐3,4‐dihydro‐5‐methyl‐6‐phenyl‐2H‐pyran‐2‐ones which were dehydrochlorinated with DBN to N,N‐disubstituted 4‐amino‐3‐chloro‐5‐methyl‐6‐phenyl‐2H‐pyran‐2‐ones.In the reaction of 2‐methyl‐1‐phenyl‐3‐diphenylamino‐2‐propen‐1‐one with dichloroketene, a product was isolated which was proven by uv, ir, nmr and chemical evidence to be the dipolar ion VI, the supposed intermediate of the polar 1,4‐cycloaddition of dichloroketene to N,N‐disubstituted enaminones.
Reissert compound studies. XXXVII. Attempts to form reissert compounds from quinazoline and cinnoline
Authors: Bhattacharjee D. , Popp F. D. 
Published: March 2009

AbstractReaction of quinazoline with trimethylsilyl cyanide and benzoyl chloride gave 2,4‐dicyano‐1,3‐dibenzoyl‐1,2,3,4‐tetrahydroquinazoline as the major product. This compound undergoes monoalkylation with methyl iodide in the presence of sodium hydride. Reaction of cinnoline with trimethylsilyl cyanide and benzoyl chloride gave 1,2‐dibenzoyl‐4‐cyano‐1,2‐dihydrocinnoline.
Substituted thiosemicarbazido/semicarbazido quinolines as possible antimalarials
Authors: Mehrotra Suman , Barthwal Jayanti P. , Pandey Bhagwan R. , Bhargava Krishna P. , Parmar Surendra S. 
Published: March 2009

AbstractSeveral 2‐aryl substituted thiosemicarbazido‐4‐methyl‐6‐methoxyquinolines and 2‐aryl substituted semi‐carbazido 4‐methyl‐6‐methoxyquinolines were synthesized and evaluated for their antimalarial activity in mice infected withPlasmodium berghei. Two of these substituted quinolines were found to exhibit 50% clearance in a dose of 500 mg./kg. administered intraperitoneally for 5 days.
Reductive opening of the thiazolidine ring. Selective N‐methylation of cysteamines
Authors: Melchiorre Carlo , Giardinà Dario , Angeli Piero 
Published: March 2009

AbstractThe reaction of thiazolidines 2 and 7 with borane was investigated. It gave N‐methylcysteamines 3 and 8 through thiazolidine ring opening. Sodium borohydride and lithium aluminum hydride were ineffective.
Methylation of 4‐phenyl‐1,2,3‐thiadiazole. Reaction of nucleophiles with N‐methyl‐1,2,3‐thiadiazolium salts and the crystal structure of the products
Authors: Auricchio S. , Brückner S. , Giunchi L. Malpezzi , Kozinsky V. A. , Zelenskaja O. V. 
Published: March 2009

AbstractThe methylation of 4‐phenyl‐1,2,3‐thiadiazole yields both N‐methylated products. These react differently with nucleophiles. The structure of the product of the reaction with morpholine has been determined through X‐ray diffraction analysis.
Synthesis of some 3,7‐disubstituted quino[3,2‐c][1,8]naphthyridines
Authors: Da Settimo Antonio , Biagi Giuliana , Primofiore Giampaolo , Ferrarini Pier Luigi , Livi Oreste , Marini Anna Maria 
Published: March 2009

AbstractThe preparation of some 3,7‐disubstituted‐5,6‐dihydroquino[3,2‐c][1,8]naphthyridines (6) by the condensation of 7‐substituted‐2,3‐dihydro‐1,8‐naphthyridin‐4‐(1H)ones (5) with o‐aminoacetophenone or o‐aminobenzophenone is described. All the 5,6‐dihydroderivatives 6 were transformed into the fully aromatic compounds 7 by heating with nitrobenzene. Only a few quino[3,2‐c][1,8]naphthyridines were previously described.
Titanium(III) chloride and electrochemical reduction of pyrazine, quinoxaline and triazine derivatives and of their salts
Authors: Armand J. , Chekir K. , Pinson J. 
Published: March 2009

AbstractThe reduction of pyrazine, quinoxaline and triazine derivatives by titanium(III) chloride leads to di‐ or tetrahydrogenated compounds. High yields of tetrahydro compounds are also obtained through the reduction of quinoxalinium salts. These results are compared with those obtained by electrochemical reduction.
Reactions of 4‐chloroacetoacetic esters with thioureas
Authors: Campaigne E. , Selby T. P. 
Published: March 2009

AbstractSeveral heterocyclic acetic acids and esters were synthesized by allowing the appropriate thiourea, ethylenethiourea or trimethylenethiourea to react with 4‐chloroacetoacetic esters, followed by acid hydrolysis to the hydrochlorides of the free acids. Both esters and acids of 2‐aminothiazole‐4‐acetic acid, 5,6‐dihydro‐imidazo[2,1‐b]thiazole‐3‐acetic acid and 6,7‐dihydro‐5H‐thiazolo[3,2‐c]pyrimidine‐3‐acetic acid were obtained.