Utility of 3-(4-Methoxyphenyl) and/or (2-Thienyl)-2-Cyano-2- Propenoyl Chloride in Heterocyclic Synthesis.

Abstract

The benzothiazepinones 2 and 3 together with the open condensation product 4 were furnished from the title compound 1a through treatment with the ambident nucleophile 2-aminothiophenol. Treatment of 1a with benzoylhydrazine afforded the pyrazolone 5 whereas the hydrazide derivatives 6a-c were obtained from treatment of 1a with phenylhydrazine, thiosemicarbazide and p-toluenesulfone hydrazide respectively. Reaction of 2-aminopyridine with 1a gave a mixture of the condensation product 7 and pyridopyrimidine 8. Hydrazinolysis of 1a at 0°C afforded a mixture of the pyrazolone 9, the bis-hydrazine 10 and the anisylidene azine 11. New sulfa drugs 12a-c were synthesised through condensation of 1a with p-aminobenzenesulfonic acid, sulfamethoxazole and sulfamethazine respectively. Esterification of 1a with different alcohols proceeded smoothly to yield the corresponding esters 13a-d. Reaction of 1 with anthranilic acids afforded the benzamides 14 which cyclized to benzoxazinones 15. Aminolysis and ethanolysis of 15b afforded 16a and 16b respectively. The quinazolinones 17 and 21 were obtained via fusion of 15 with p-toluidine and/or ammonium acetate. Reaction of hydrazine hydrate with 15 in dioxane at 0°C gave the pyrazolopyrimidinone 18 while reaction in refluxing n-butanol yielded the pyrazolo [5,1-b] quinazolinones 19 and 20 as well as the azine 11. Chlorination of 21 yielded 4-chloroquinazoline 22 which was transformed into quinazolinthione 23 and hydrazinoquinazoline 24 via the reaction with thiourea and hydrazine hydrate respectively.