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The synthesis of a series of methyl 3-amino-4-aryl(or methyl)sulfonylthiophene-2-carboxylates by reaction of 3-alkoxy-2-aryI(or methyl)sulfonylacrylonitriles with methyl thioglycolate in the presence of triethylamine is described. Hydrolysis/decarboxylation of the ester at the 2-position and acylation of the resulting amine represents a convenient route to 4-arylsulfonyl-3-carboxamidothiophenes. Attempted acylation of a title aminothiophene under standard conditions was unsuccessful.

The title aminopyrroles and thiophene have been prepared by condensation of methyl (cyanomethyl-sulfonyl)acetate with various α-amino ketones or 2-mercaptoacetaldehyde, respectively. Subsequent cyclization of these compounds by reaction between the amine and activated methylene has led to various ester-substituted thiazine- and thiadiazine-based bicyclic derivatives. In addition, cyclization of the title compounds by intramolecular coupling of the amine and ester has led to the analogous bicyclic thiazin-3(2H)-ones. Attempted hydrolysis of the ester-substituted bicyclics to the corresponding carboxylic acids was unsuccessful.

The synthesis and selected reactions of 2-amino-3-(cyanomethylsulfonyl)thiophene is reported. In particular, cyclization reaction of the versatile aminothiophene yielded a number of novel thieno[3,2-b][1,4]-thiazine 1,1-dioxides, as well as the analogous thieno[2,3-e][1,3,4]thiadiazine 4,4-dioxide. Reaction of the thienothiazine system with hydrazine was subsequently explored, which resulted in either ring-opening of the thiazine and formation of an aminopyrazole or solely ring cleavage depending on the thiazine substituent. Additionally, the synthesis of bis(2-amino-3-thienyl)sulfone and the corresponding bis-acetamide is described.

The synthesis and selected reactions of the versatile heterocycle 2-amino-3-cyanomethylsulfonyl-4,5-dimethylfuran is reported. In particular, cyclization reaction of the aminofuran yielded a number of novel furo[3,2-b]thiazine 1,1-dioxides. Additionally, a novel tetracyclic system, namely a pyrrolo[2′,3′:5,6]-[1,4]thiazino[3,2-b]quinoline 4,4-dioxide, is prepared via an intramolecular triple-cyclization in which the furan ring is opened and reclosed as a pyrrole.

A series of indole, thiophene and pyrrole-fused 1,3-oxazine-2,4-diones, 2-methyl-1,3-oxazin-4-ones and 2-dimethylamino-1,3-oxazin-4-ones were synthesized and evaluated as antitumor agents.

A series of novel 5,6-dimethylpyrrolo[2,3-d]-1,3-oxazin-4-ones were synthesized from 2-amino-3-tert-butoxy-carbonyl-4,5-dimethylpyrroles. Two methods were used, cyclodehydration of 2-acylamino-3-carboxypyrroles with acetic anhydride and direct conversion of the 5,6-dimethylpyrrolo[2,3-d]-1,3-oxazin-2,4-diones to the title compounds with an anhydride directly providing the 2 substituent. Molecular modeling techniques revealed that these pyrrolo[2,3-d]oxazinones were rigid analogues of the allylamine antifungals. The compounds were tested for in vitro activity against Tricophyton and Scopulariopsis sp.

Reductive aromatization and demethylation of 1,3-disubstituted-2-amino-5-oxo-7a-methyl-5,7a-dihydroindoles with zinc, pyridine and a trace of water yields 1,3-disubstituted-2-amino-5-hydroxyindoles. Simple derivatives of the 5-hydroxy substituent are described.

Cycloaddition and addition reactions of ethyl propiolate with a series of 1,3,5-substituted-2-amino-4-methylpyrroles to form, 1,3-disubstituted-5-oxo-7a-methyl-5,7a-dihydroindoles are described. High resolution mass spectral and pmr data are presented.

A series of twelve newly synthesized derivations of 3-benzoyl-4,7-dihydro-7-oxopyrrolo[3,2-b]pyridine-6-carboxylic acid from 2-methyl-3-benzoyl-4-aminopyrrole is reported.

A series of substituted pyrrolo[2,3-e][1,3,4]thiadiazine 4,4-dioxides is synthesized from 1-substituted-2-amino-3-cyanomethylsulfonyl-4,5-dimethylpyrroles.

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.

Attempted hydrolysis of the ester of 3-methoxycarbonyl-1H-thieno[2,3-e][1,3,4]thiadiazine 4,4-dioxide (I) under acidic conditions gave the ring-contracted thieno[2,3-d][1,2,3]thiadiazole (V) instead of the expected carboxylic acid. In addition to a discussion of the reaction, a plausible mechanism is presented.

The preparation of a variety of 8-cyano-1,4-dihydro-7-phenyl-4-oxopyrrolo[1,2-a]pyrimidine-3-carboxylicacids and 8-cyano-1,4-dihydro-7-p-fluorophenyl-4-oxopyrrolo[1,2-a]pyrimidine-3-carboxylic acids is described.

The one-step synthesis of 8-t-butoxycarbonyl-6,7-dimethyl-2-oxo-1,2,3,4-tetrahydropyrrolo[1,2-a]pyrimidine from acetyl methyl carbinol, 3-aminopropionic acid, and t-butyl cyanoacetate is reported. Utilizing a similar technology under basic conditions, 7-substituted 5,6-dimethyl-2-oxo-2,3-dihydro-(1H)-pyrrolo[1,2-a]imidazole is synthesized from acetyl methyl carbinol, ethyl glycinate, and the appropriate acetonitrile.

A route for the synthesis of various derivatives of 1,4-dihydro-4-oxopyrrolo[3,4-b]pyridine-3-carboxylic acid from 2-phenyl-3-amino-4-t-butoxycarbonyl-5-methylpyrrole hydrochloride is reported.

A series of 3-substituted 2-amino-4,5-dimethylpyrrole-1-acetic acid derivatives were synthesized. The condensation of acetyl methyl carbinol, ethyl glycinate, and the appropriate acetonitrile yielded ethyl 3-substituted 2-amino-4,5-dimethylpyrrole-1-acetate, which was consequently hydrolyzed to produce the corresponding carboxylic acid. The acetamide and trifluoroacetamide series were synthesized by reacting the ethyl 2-aminopyrrole-1-acetates with acetyl chloride or trifluoroacetic anhydride respectively. The corresponding 2-acetamidopyrrole-1-acetic acids were formed by basic hydrolysis of the ethyl esters.

A facile route for the synthesis of substituted pyrrolo[2,3-d]pyrimidine-2,4-diones from substituted 2-amino-3-cyano-4-methylpyrroles is reported.

The synthesis of a new pyridoindolizine, in particular, pyrido[2,3-α]indolizine, was carried out using 2-methyl-3-t-butoxycarbonyl-4-aminopyrrole as the starting material.

A route for the synthesis of various derivatives of 7-oxopyrrolo[3,2-b]pyridine-6-carboxylic acid from 2-methyl-3-carbomethoxy-4-aminopyrrole is reported.

A facile route for the synthesis of pyrrolo[ 1,2-α]pyrimidine derivatives and data for structural assignment are reported.

A facile route for the synthesis of substituted 2-amino-3-cyano-4-methylpyrroles from N-acetyl-α-amino ketones and malononitrile is reported.

O-Ethyl-N-substituted pyrrolidonium fluoroborate salts were condensed under basic conditions with active methylene compounds to give vinylogous carbamates and cyanamides.

A general route for the synthesis of 2-amino-3-(alkyl or aryl)sulfonyl pyrroles is reported.