Reactions of 4<i>H</i>-Pyran-4-thiones with Ammonia, Hydrazine, and Guanidine

Abstract

Abstract The reaction of 4H-pyran-4-thiones with ammonia gave 4(1H)-pyridinethiones or bis(4-pyridyl) disulfide, while that of 3-methoxy-2-methyl-4H-pyran-4-thione with guanidine gave the 1,3-thiazine derivative. 4H-Pyran-4-thiones reacted with hydrazine to afford pyridazines, pyrazoles, and 1-amino-4(1H)-pyridinethiones. 4H-Pyran-4-thiones having the hydroxyl group in the β-position gave the pyridazine derivatives.