Abstract
4-Amino-8-methyl-2-oxo/thioxoquinoline and 4-hydrazino-8-methyl-2-oxo/thioxoquinoline have been synthesized and used as synthons for the preparation of some new 4-substituted quinolin-2-ones and quinolinethiones. Also, 4-chloro-2-(ethoxycarbonylmethylthio)-8-methylquinoline was synthesized and utilized as a precursor for some new triazoles, thiadiazoles, benzimidazoles, benzthiazoles, and oxadiazoles bearing the quinoline moiety at position 2.