Multicomponent one-pot synthesis of pyrido[3′,2′:4,5]thieno[3,2-b]pyridines as a novel approach to condensed pyridines

Multicomponent one-pot reactions of aromatic aldehydes, cyanothioacetamide, ethyl benzoylacetate, acetone and malononitrile in the presence of N-methylmorpholine or similar reactions of pyridinethiones or -thiolates with malononitrile and acetone afford the title compounds, which were unknown before.