Synthesis of Novel Quinolone and Coumarin Based 1,3,4-Thiadiazolyl and 1,3,4-Oxadiazolyl N-Mannich Bases as Potential Antimicrobials

Two series of 1,3,4-thiadiazole and 1,3,4-oxadiazole derivatives have been synthesized and characterized by elemental and spectral (IR, 1H-NMR) data. The hydrazide derivatives of 4-hydroxy quinolone and coumarin moiety were refluxed in carbon disulfide in ethanolic potassium hydroxide to obtain the corresponding hydrazinecarbodithioate salts which were then treated in two ways with (i) sulfuric acid and (ii) hydrochloric acid at cooled...