Glyoxyl analogs of indole phytoalexins: Synthesis and anticancer activity

Abstract

Glyoxyl analogs of indole phytoalexins brassinin, 1-methoxybrassinin, brassitin, 1-methoxybrassitin and 1-methoxybrassenin B were prepared, using (1H-indol-3-yl)-, (1-methoxyindol-3-yl)- and [1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)indol-3-yl]glyoxyl chlorides as starting compounds. Synthesized products were examined for their antiproliferative activity against human cancer cell lines Jurkat (T-cell acute lymphoblastic leukemia), MCF-7 (breast adenocarcinoma, estrogen receptor-positive), MDA-MB-231 (breast adenocarcinoma, estrogen receptor-negative), HeLa (cervical adenocarcinoma), CCRF-CEM cell line (T-cell acute lymphoblastic leukemia) and A-549 cell line (lung adenocarcinoma), and their activity compared with natural phytoalexins and corresponding (1H-indol-3-yl)acetic acid derivatives. The highest potency with IC50 3.3–66.1 μmol l–1 was found for glyoxyl analogs of 1-methoxybrassenin B.