Aminothiazole derivatives. II. A facile synthesis of condensed 4-aminothiazole derivatives using α-bromolactams and thioamides

The reaction of an α-bromolactam with a thioamide was found to give a cyclic 4-aminothiazole derivative. Novel heterocyclic compounds such as 4,5,6,7-tetrahydrothiazolo[4,5-b]pyridines 10 , 5,6,7,8-tetrahydro-4H-thiazolo[4,5-b]azepines 11 , 4,5,6,7,8,9-hexahydrothiazolo[4,5-b]azocine 12 and 9,10-dihydro-4H-thiazolo[4,5-b][1]benzazepines 18 were thus prepared and the utility of this method in the construction of 4-aminothiazole-containing compounds was suggested.