Cyanothioacetamide in Heterocyclic Synthesis: A New Approach for the Synthesis of 2-Pyridothione and 2-Pyridazinothione Derivatives

Cyanothioacetamide (1) undergoes self condensation to give 4,6-diamino-3-cyano-2-pyrido-thione (2). The latter was utilised in synthesis of pyrido[2,3-c]pyrazole, pyrido[2,3-d]pyrim idine, bis-(pyridothione derivatives) through reaction with hydrazine hydrate, ethoxycarbonyl isothio-cyanate and cinnamonitrile derivatives. Also 1 undergoes self dimerisation to give 13, the latter form the pyridazine derivative on coupling with benzenediazonium chloride.