Synthesis and structure–activity relationships of N-aryl(indol-3-yl)glyoxamides as antitumor agents

The synthesis and study of the structure-activity relationships of cytotoxic compounds based on N-pyridinyl or N-aryl-2-(1-benzylindol-3-yl)glyoxamide skeleton, represented by the lead structures D-24241 and D-24851, are described. The presence of N-(pyridin-4-yl) moiety was crucial for activity and 2-[1-(4-chloro-3-nitrobenzyl)-1H-indol-3-yl]-2-oxo-N-(pyridin-4-yl)acetamide (55), the most potent derivative, showed IC(50)=39 nM, 51 nM and 11 nM against HeLa/KB (human cervix carcinoma), L1210 (murine leukemia) and SKOV3 (human ovarian carcinoma) cell lines proliferation assay, respectively, as active as the lead compounds.