Synthesis of novel thiazoles bearing hydrazine,thiosemicarbazide, thiazole,and thiazolidinone moieties

Thiazolecarboxylate esters (I) and (II) react with hydrazine hydrate to give the acid hydrazides (III) and (IV), which then react with KSCN and PhNCS to give high yields of the thiosemicarbazides (V)-(VIII). Cyclocondensation of the thiosemicarbazide (V) with 3-phenyl-3-chloro-2-oxopropionic acid derivatives gives compounds with two thiazole moieties (IX)-(XIV). The reaction of the phenylthiosemicarbazides (VII) and (VIII) with chloroacetyl chloride and (or) chloroacetic acid affords the thiazolidinonethiazoles (XV) and (XVI).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2832–2836, December, 1991.