Abstract We have synthesized 3-(2-R-thiazol-4-yl) coumarins (R= H, CH 3, CH 2 CN, Ar) by condensation of 3-(α-bromoacetyl) coumarins with thioamides. We obtained 3-(4-R-thiazol-2- yl) coumarins (R= H, Ar) by several methods. By reaction of 2-cyanomethyl-4-phenylthiazole with 2-hydroxybenzaldehydes, we synthesized 2-imino-3-(4-phenylthiazol-2-yl) coumarins, which were converted to the corresponding coumarins by acid hydrolysis. For 3-(2-R- ...