Synthesis, study of the structure, and modification of the products of the reaction of 4-aryl-4-oxobut-2-enoic acids with thiourea

A number of previously undescribed derivatives of 2-amino-5-(2-aryl-2-oxoethyl)thiazol-4(5 H )-one containing electron-donating substituents in the aromatic ring were synthesized by the reaction of ( E )-4-aryl-4-oxobut-2-enoic acids with thiourea. Reduction of the reaction products with NaBH 4 yielded diastereomeric alcohols, whereas bromination in AcOH was accompanied by elimination of HBr and the formation of ( Z )-2-amino-5-(2-aryl-2-oxoethylidene)thiazol-4(5 H )-ones.