Synthesis of some new thieno[2,3-b]pyridines, pyrimidino[4′,5′: 4,5]thieno[2,3-b]-pyridines, and 2,3-dihydro-1,3,4-thiadiazoles

Abstract

Thieno[2,3-b]pyridines were synthesized from 6-benzofuran-2-yl-4-phenyl-2- sulfanylpyridine-3-carbonitrile and each of chloro acetone, ethyl chloroacetate, -bromoacetophenone, and chloroacetonitrile. These compounds were conveniently converted into novel pyrido[4′,5′:4,5]thieno[3,2-d]pyrimidines. Also, 2,3-dihydro-1,3,4-thiadiazole was synthesized from hydrazonoyl halides and 2-benzofuran-2-yl-3-(phenylamino)-3-thioxopropanenitrile. The structures of the products have been elucidated by elemental analyses, spectral data studies, and alternative syntheses whenever possible. The newly synthesized compounds were tested towards microorganisms.