Abstract

Thiourea reacts with dialkyl acetylenedicarboxylates in solventless conditions to form 1: l adducts, which undergo a cyclization reaction to produce alkyl Z-2—(2-amino-4-oxo-1, 3- thiazol-5 (4H)-yliden) acetates under microwave irradiation and also under thermal conditions in solvent-less system in fairly good yields. Stereochem-istry of the ethyl Z—2-(2— amino-4-oxo—l, 3-thiazol-S (4H)-yliden)—acetate was established with using of X-ray single crystal structure analysis. The reaction is completely stereoselective.