Click chemistry-based synthesis and anticancer activity evaluation of novel C-14 1,2,3-triazole dehydroabietic acid hybrids

A concise and efficient synthetic approach has been established to readily access a series of novel C-14 1,2,3-triazole-tethered dehydroabietic acid derivatives in moderate to high yields. In vitro antiproliferative activity evaluation indicated that most of the hybrids exhibited potent inhibitory activities in a variety of cancer cell lines with low micromolar to submicromolar IC50 values. Further studies demonstrated that some of these analogues such as 20, 21, and 24 were also effective against adriamycin-resistant MCF-7 clone at low concentrations in a dose-dependent manner. Notably, the most potent compound 24, which possesses a 3-(tert-butoxycarbonylamino)phenyl-substituted triazole moiety, not only exhibited obviously improved IC50 values ranging from 0.7 to 1.2 μM against a panel of tested cancer cells, but also showed very weak cytotoxicity on normal cells. Preliminary mechanism studies indicated that compound 24 could induce apoptosis in MDA-MB-231 cells and was worth developing into a novel natural product-like anticancer lead by proper structure modification.