Synthesis of Dihydropyridine, Alkylthiopyridine, Thienopyridine and Pyridothienopyrimidine Derivatives

Abstract

The reaction of arylidene cyanothioacetamide (1a,b) with acetylacetone (2) gave dihydropyridine derivatives (3a,b). Compounds (3a,b) on reaction with some halogenated derivatives (5A-C) to afford 2-alkylthiopyridine derivatives (6-8). The compounds (3a,b) reacted with (5A-G) to give thieno[2,3-b]pyridine derivatives (9-13). The compounds (9, 10) reacted with formic acid, (9) with formamide, and (10) with acetic anhydride to give (14-16), respectively.