Antileukemic activity of substituted ureidothiazoles, ureidothiadiazoles, and related compounds

Abstract
A number of ureidothiazole and ureidothiadiazole derivatives related to ethyl 4-[[(2-thiazolylamino)carbonyl]-amino]benzoate were prepared and evaluated against the leukemia P-388 tumor system in mice. Preliminary structure-activity relationship study revealed that, among other considerations, active compounds of this series contain either an isothioureido [> N-C(S-).dbd.N-] or an isothiosemicarbazono [> N-C(S-).dbd.N-N.dbd.] structural unit.