antiproliferative activity for N'-(4-(4-chlorophenyl)-6-(trifluoromethyl)pyrimidin-2-yl)-5-ethyl-2,4-dihydroxybenzothiohydrazide (5b) was found. The antiproliferative potency of some compounds was similar to that of cisplatin. Analogs with the Et substituent on benzenediol moiety displayed higher potency than with the unsubstituted one. The influence of N'-substitution on antiproliferative activity of compounds