Etude de nouveaux systemes aromatiques possédant des propriétes diéniques: [2]benzothiéno[5,6-g] phtalazines,thiéno[3,4-g]phtalazines et leurs analogues furanniques

Derivatives of new polydienic systems have been isolated. Two [2]benzothienophthalazines, nitrogenous analogues of unknown anthra[2,3-c]thiophens are described. A furo[3,4-g]-phtalazine and a thieno[3,4-g]phthalazine are isolated. These different compounds react with philodienes. The first tetraza-2,3,8,9-naphthacenes have been synthesized. Structures of these compounds are proved by chemical and spectrographical methods.     

New polyazaheterocycles. 9-Methyl-di-s-triazolo[4,3-a:4,3-c]pyrimidine and 9-methyl-s-triazolo[4,3-c]tetrazolo[1,5-a]pyrimidine

9-Methyl-di-s-triazolo[4,3-a:4,3-c]pyrimidine and 9-methyl-s-triazolo[4,3-c]tetrazolo[1,5-a]pyrimidine have been synthetized from 4-hydrazino-7-methyl-s-triazolo[4,3-c]pyrimidine. Structural assignments based on nmr, ir and chemical manipulations are discussed.     

Action de réactifs nucléophiles sur les phényl-5 thiéno[3,2-b]pyrannone-7 et phényl-2 benzo[b]thiéno[3,2-b]pyrannone-4

Reactions of 5-phenylthieno[3,2-b]pyran-7-one, 2-phenylbenzo[b]-thieno[3,2-b]pyran-4-one and the corresponding thiones with sodium ethylate, guanidines, hydrazines and amines are described and compared to those observed with benzopyranones.     

The synthesis of [1]benzothieno[2,3-c]quinolines, [1]benzothieno[2,3-c][1,2,4]triazolo[4,3-a]quinoline,and [1]benzothieno[2,3-c]tetrazolo[1,5-a]quinoline

Photocyclization of 3-chloro-N-phenylbenzo[b]thiophene-2-carboxamide 10 afforded [1]benzothieno[2,3-c]-quinolin-6(5H)-one 11 which was chlorinated to 6-chloro[1]benzothieno[2,3-c]quinoline 12 followed by dechlorination to give [1]benzothieno[2,3-c]quinoline 5 . A series of 6-substituted alkoxy and thioalkoxy[1]benzothieno[2,3-c]quinoline derivatives were prepared along with the N-methyl quaternary salt 13 of 5 . 6-Chloro[1]-benzothieno[2,3-c]quinoline 12 was converted into 6-hydrazino[1]benzothieno[2,3-c]quinoline 23 which upon treatment with formic acid yielded [1]benzothieno[2,3-c][1,2,4]triazolo[4,3-a]quinoline 6 . Treatment of 23 with nitrous acid resulted in [1]benzothieno[2,3-c]tetrazolo[1,5-a]quinoline 7 . Compounds 6 and 7 are novel heterocyclic ring systems.     

The synthesis of imidazo[4,5-c] - and v-triazolo[4,5-c] pyridazines

The parent imidazo[4,5-c]pyridazine (IV) has been prepared for the first time by three different routes. 1-Methylimidazo[4,5-c]pyridazine (XX) and 3-methylimidazo[4,5-c]pyridazine (XXVII) have been prepared by unequivocal syntheses. The constitution of the methylation product of imidazo[4,5-c]pyridazine-2-thiol (VIII) has been shown to be 2-methylthioimidazo[4,5-c]-pyridazine (IX) by the unequivocal syntheses of 1-methylimidazo[4,5-c]pyridazine-2-thiol (XXIII) and 3-methylimidazo[4,5-c]pyridazine-2-thiol (XXXIII). Likewise, the structure of the methylation product (XIII) was shown to be S-methylation by the unequivocal syntheses of 1-methyl-2-methylthio-6-chloroimidazo[4,5-c]pyridazine (XXIV) and 3-methyl-2-methylthio-6-chloroimidazo[4,5-c]pyridazine (XXXI), respectively. Several 7-substituted amino-v-triazolo-[4,5-c]pyridazines (XXXVIII) have been prepared from 7-chloro-v-triazolo[4,5-c]pyridazine (XXXVII).     

Synthesis of thieno[3,4-c] and thieno[3,2-c][2,1]benzothiazepines

Starting from [4,3-c] and [3,2-c] methyl chlorosulfonylthiophenecarboxylates the synthesis of ketones 7 and 8 is described. These compounds are the first two representatives of the new thieno[3,4-c] and thieno-[3,2-c][2,1]benzothiazepine ring systems. The formation of methyl 3-chlorosulfonylthiophene-2-carboxy-late is also revised.     

Pyrrolothiénopyrazines: Etude chimique de la pyrrolo[1,2-a]thiéno[2,3-e]pyrazine

The reactivity of pyrrolo[1,2-a]thieno[2,3-e]pyrazine towards quaternisation, bromination, nitration, Friedel-Crafts, Vilsmeier-Haack and Reissert reactions was studied. Assignment of structures to the product is based upon ir, nmr and mass spectral studies.     

The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 9. Phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline,benzo[f]phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline,and benzo[h]-phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline

The synthesis of three novel polycyclic heterocyclic ring systems are reported via photocyclization. The specific final products in these ring systems are: phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 13 ), benzo[h]-phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 14 ), and benzo[f]phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 15 ).     

The synthesis of pyrimido[4,5-c]pyridazines and pyrimido[5,4-c]pyridazines

The Hofmann reaction on 6-methylpyridazine-3,4-dicarboxamide (1) gave a mixture of 3-methylpyrimido[4,5-c]pyridazine-5,7-dione (2), 3-methylpyrimido[5,4-c]pyridazine-6,8-dione (3) and an acid (4) of unknown structure. The Hofmann reaction on pyridazine-3,4-dicarboxamide (9) gave a mixture of pyrimido[4,5-c]pyridazine-5,7-dione ( 10 ) and an acid ( 11 ) of unknown structure. The reaction of 3-amino-6-methylpyridazine-4-carboxamide ( 18 ) with ethyl orthoformate gave 3-methylpyrimido[4,5-c]pyridazin-5-one ( 21 ). 4-Aminopyridazine-3-carboxamide ( 36 ) upon fusion with urea gave pyrimido[5,4-c]pyridazine-6,8-dione ( 37 ) while with ethyl orthoformate 36 gave pyrimido[5,4-c]pyridazin-8-one ( 38 ). Pyrimido[5,4-c]-pyridazine-8-thione ( 39 ) was obtained by the action of phosphorus pentasulfide on 38. 4-Amino-3-cyanopyridazine ( 16 ) when treated with formamide produced 8-aminopyrimido[5,4-c]-pyridazine ( 41 ). The synthesis of 4-aminopyridazine-3-carboxamide ( 36 ) and 4-amino-3-cyanopyridazine ( 16 ), both key intermediates in the synthesis of the novel pyrimido[5,4-c]pyridazine ring system was accomplished by the Reissert reaction of 4-aminopyridazine-2-oxides and subsequent conversion of the nitrile to the amide.     

New [g]-fused [1,2,4]triazolo[1,5-c]pyrimidines: Synthesis of pyrido[3,2-e] and [4,3-e][1,2,4]triazolo[1,5-c]pyrimidine,pyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidine and [1,2,4]triazolo[1,5-c]pteridine derivatives

A number of 2-aryl-substituted pyrido[3,2-e] and [4,3-e][1,2,4]triazolo[1,5-c]pyrimidines and [1,2,4]triazolo[1,5-c]pteridines 11,12a,b,e , their corresponding 5-carbonyl derivatives 7,8a,b,e and some pyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidin-5-ones 7,8c,d have been synthesized, according to different pathways. The new tricyclic heterocycles were prepared with the aim of studying their possible benzodiazepine receptors affinity.     

A novel preparation of thiazolo[5,4-c]pyridines and the synthesis of some imidazo[4,5-c]pyridines and oxazolo[4,5-c]pyridines

Diethoxymethyl acetate was used to cyclize o-disubstituted aminopyridines to oxazolo[4,5-c]pyridines and imidazo[4,5-c]pyridines. All the possible imidazole-methylated imidazo[4,5-c]pyridines were prepared. A novel synthesis of 2-substituted thiazolo[5,4-c]pyridines and 4-amino-3-pyridinethiol was discovered.     

1,2,4-Triazino[4,3-c]- and [2,3-c]quinazolines

This paper describes the reactions of 2-o-aminophenyl-1,4,5,6-tetrahydro-1-methyl-1,2,4-triazine with a variety of reagents to give substituted 1,2,4-triazino[4,3-c]quinazolines or 1,2,4-triazino[2,3-c]quinazolines. Certain representative compounds of these two new heterocyclic systems were characterized by the tlc, ir, nmr, mass spectra, and identified by unequivacol synthesis.     

The synthesis of monomethoxy[1]benzothieno[2,3-c]quinolines

A series of monomethoxy[1]benzothieno[2,3-c]quinolines 24-28 were prepared by photocylization of the appropriate 3-chloro-N-phenylbenzo[b]thiophene-2-carboxamides 9–13 to [1]benzothieno[2,3-c]quinolin-6(5H)-ones 14-18 followed by chlorination to 6-chloro[1]benzothieno[2,3-c]quinolines 19-23 then dechlorination resulting in the title compounds except for 25 which was achieved by direct reduction of 15 . Reaction of 24-28 with methyl iodide provided the corresponding N-methyl quaternary salts 29-33 . Also, conversion of 4-meth-oxy[1]benzothieno[2,3-c]quinolin-6(5H)-one 16 to 4-methoxy-6-methylthio[1]benzothieno[2,3-c]quinoline 35 and 4,6-dimethoxy[1]benzothieno[2,3-c]quinoline 36 is described.     

Synthesis of novel imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines and pyrimido[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines

Several 1 1-amino-5H-pyrrolo[2,1-c][1,4]benzodiazepines have been used as starting material to prepare a number of derivatives of 9H-imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines and 10H-pyrimido[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines. The imidazole nucleus was built by reaction of amidines with ethyl bromopyruvate or aminoacetaldehyde dimethylacetal. Several derivatives of imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine have been prepared by formylation of the pyrrole ring followed by formation of thioamides. Condensation of 11-amino-5H-pyrrolo[2,1-c][1,4]benzodiazepines with diethyl ethoxymethylenemalonate afforded intermediate diesters which were transformed into the corresponding 10H-pyrimido[1,2-a]pyrrolo[2,1-c]-benzodiazepines.     

Synthesis of substituted furo[3,2-e][1,2,4]triazolo[4,3-c]pyrimidines and furo[3,2-e]tetrazolo[1,5-c]pyrimidines

A series of substituted furo[3,2-e][1,2,4]triazolo[4,3-c]pyrimidines and furo[3,2-e]tetrazolo[1,5-c]pyrimidines were obtained from reactions of substituted 2-dimemylamino-4-hydrazmofuro[2,3-d]pyrimidines with orthoesters or sodium nitrite in acetic acid, respectively.     

Synthesis and Structure of Di-N-arylpyrrolo[1,2-c;5,6-c]cyclooctanes

Di-N-arylpyrrolo[1,2-c;5,6-c]cyclooctanes were synthesized for the first time by the cyclization of N,N-dipropynylarylamines in a superbasic medium.     

Thiénopyrimidines VIII. Etude des thiéno[2,3-d] pyrimidinethiones

Substitution and addition reactions of thieno[2,3-d] pyrimidine-thiones have been studied. These reactions led to S- and N- substituted derivatives whose structure was established by the synthetic routes as well as by the ir and pmr spectra.     

Furannes et pyrroles disubstitués en 2,3. XVI synthèse de furo[3,2-c]pyranones-4 et nouvelle voie d'accès aux furo[3,2-c]pyridines

Treatment of 4-hydroxy-6-methylpyran-2-one with chloracetalhyde in basic aqueous medium gave 6-methylfuro[3,2-c]pyran-4-one. This compound reacted with ammonium hydroxide and some primary amines to form the corresponding N-substituted furo[3,2-c]pyrid-4-ones which may also be obtained from 4-hydroxy-α-pyridones. Furo[3,2-c]pyran-4-one was acylated at the 2 position and 4-chloro-6-methylfuro[3,2-c]pyridine easily gave 4-substituted derivatives by displacement of the halogen atom.     

Proton magnetic resonance studies of compounds with bridgehead nitrogen: XXVIII—Stereochemical studies with perhydropyrido[1,2-c] [1,6,3]dioxazocines and 2-alkylperhydropyrido[1,2-c] [1,3,6]oxdiazocines

A series of perhydropyrido[1,2-c][1,6,3]dioxazocines and 2-alkylperhydropyrido[1,2-c][1,3,6]oxdiazocines have been prepared. 6-p-Nitrophenyl-3,4-dimethylperhydropyrido[1,2-c][1,6,3]-dioxazodioxazocine is shown to adopt the cis fused ring conformation in solution with the nitrogen lone pair axial with respect to the piperidine ring. The 2-alkylperhydropyrido[1,2-c][1,3,6]oxdiazocines adopt a similar cis fused ring conformation and with increasing steric requirement of the 2-alkyl substituent the 8-membered ring increasingly favours the chair-chair conformation, rather than the chair–boat conformation favoured by the 2-methyl substituted compound.     

Electrophilic substitution of furo[3,2-c] pyridine

Furo[3,2-c] pyridine (I) was nitrated to give 2-nitrofuro[3,2-c]pyridine (II). Bromination and chlorination of I gave, respectively, 2,3-dibromo-2,3-dihydrofuro[3,2-c]pyridine (III) and 2,3-dichloro-2,3-dihydrofuro[3,2-c]pyridine (IV). Oxidation of I with hydrogen peroxide afforded furo[3,2-c]pyridine 5-oxide (V) which was converted to I by phosphorus trichloride and to 4-chlorofuro[3,2-c]pyridine (VI) by phosphorus oxychloride.