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

Abstract Aim To synthesize novel 14- O -derivatives of natural oridonin and evaluate their anti-tumor activity. Methods Different 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 . Results Ten novel compounds were synthesized and their structures were identified by IR, MS and 1 H 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. Conclusion As 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.