1-(2-Mercaptobenzenesulfonyl)-3-hydroxyguanidines--novel potent antiproliferatives, synthesis and in vitro biological activity.

Twenty four 1-[2-alkylthio-5-(azol-2 or 5-yl)-4-chlorobenzenesulfonyl]-3-hydroxyguanidines 6a-x have been synthesized in order to evaluate their biological activity. Compounds 6a, 6c, 6d, 6f, 6g, 6i-p, 6r-t, and 6v-x were tested for their in vitro anticancer activity at the US National Cancer Institute. The highest in vitro anticancer activity was found for compounds 6d, 6g and 6k with GI(50) average value in the range 1.62-1.86 μM, and TGI mean values 3.72-4.47 μM, whereas the remaining compounds showed broad spectrum of anticancer activity at low micromolar GI(50) level against all tested cancer cell lines. These results were subjected to CoMSIA analysis to establish quantitative structure-activity relationships. The results evidence that potency of these compounds correlates mainly with hydrophobic and polar surface properties of substituents located both at 2 and 5 positions of 1-(4-chlorobenzenesulfonyl) moiety of investigated 3-hydroxyguanidine series.