Synthesis and Anti-tumor Activity of 14-O-Derivatives of Natural Oridonin

AimTo synthesize novel 14-O-derivatives of natural oridonin and evaluate their anti-tumor activity.MethodsDifferent anhydrides were conjugated with 14-hydroxyl and further reacted with amino acid esters via amidation. The cytotoxicity of derivatives against the human cancer cells BGC-7901, SW-480, HL-60, BEL-7402, A549 and B16 in vitro were evaluated by MTT assay. The anti-tumor activity of 2c and 2d in mice with H22 liver tumor was tested in vivo.ResultsTen novel compounds were synthesized and their structures were identified by IR, MS and 1H NMR. The biological study results showed that compounds 2c, 2d, and 3e have potent cytotoxicity against the six cancer cell lines. Compounds 2c and 2d have stronger anti-tumor activity than oridonin and cyclophosphamide.ConclusionAs a possible result of the present findings, the 14-O-derivatives 2c, 2d and 3e of oridonin as potential anticancer drug candidates may be worthy of further studies.