Anticancer Activity of 4-Aryl-1,4-Dihydropyridines

We have synthesized 22 symmetric and asymmetric 4-aryl-1,4-dihydropyridines (1,4-DHPs) by a "green" microwave-assisted one-pot multicomponent Hantzsch reaction and evaluated their cytotoxicity to three human cancer cell lines regarding U-251MG (human glioblastoma), HeLa 229 (human cervical adenocarcinoma), and MCF-7 (human breast carcinoma). None of the 1,4-DHPs were cytotoxic to U-251MG cells. Most of the 1,4-DHPs did not affect HeLa 229 or MCF-7 cell viability. On the other hand, symmetric 1,4-DHPs 18 (diethyl 4-(4-benzyloxyphenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate), 19 (diethyl 4-(4-bromophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate), and 20 (diethyl 4-(3-fluorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate) reduced the HeLa (IC50 = 3.6, 2.3, and 4.1 mu M, respectively) and MCF-7 (IC50 = 5.2, 5.7, and 11.9 mu M, respectively) cell viability. These 1,4-DHPs were more cytotoxic to the HeLa and MCF-7 cells than to the GM07492 (normal human fibroblast) cells, as evidenced by their selectivity indexes. Therefore,1,4-DHPs 18, 19, and 20 may serve as novel lead compounds to discover other 1,4-DHP derivatives with improved anticancer potency and selectivity.