Studies on the synthesis of some styryl‐3‐cyano‐2(1 H )‐pyridinethiones and polyfunctionally substituted 3‐aminothieno[2,3‐ b ]‐pyridine derivatives

The 3‐cyano‐4,6‐dimethyl‐2(1 H )‐pyridinethione was condensed with benzaldehyde in basic solution leads to styryl‐3‐cyano‐2(1 H )‐pyridinethiones. Treatment of cinnamicaldehyde with cyanothioacetamide to give cinnamylidencyanothioacetamide, which can be cyclized with the appropriate ketones to afford the 3‐cyano‐5,6‐polymethylene‐4‐styryl‐2(1 H )‐pyridinethione derivatives. The polyfunctionally substituted 3‐aminothieno[2,3‐ b ]pyridine derivatives were obtained in good yield by cyclization of 3‐cyano‐2(1 H )‐pyridinethione derivatives with appropriate α‐halogeno carbonyl compounds and nitrile, respectively.