An efficient conversion of maleimide derivatives to 2-thioxo imidazolidinones

Starting from maleimidederivatives, a series of 2-thioxoimidazolidinones was prepared through two different procedures. These syntheses have achieved in two steps via reaction between maleimide derivatives 1,semicarbazide hydrochloride 9 and isothiocyanates5,the best results being obtained under acid conditions (AcOH or heteropolyacid in ethanol or acétonitrile). The synthesized compounds 11a-f and substituted thiohydantoins 6a-h, 8a-h were screened for their in vitro anti-bacterial activity against four bacterial strains.