Daphnane diterpene esters from flower buds of Daphne genkwa and their cytotoxic effects on cancer cells

Objective To study daphnane diterpene esters from the flower buds of Daphne genkwa and to evaluate their cytotoxicity against tumor cells.Methods The compounds were isolated and purified by means of chromatographic techniques and their structures were identified on the basis of spectral features.Cytotoxic activity against NCI-H1975 lung cancer cells and SK-BR-3 breast cancer cells were assessed for all the compounds by MTT method.Results Six compounds were isolated and identified as isoyuanhuacin(1),yuanhuacin(2),yuanhuatin(3),yuanhuagin(4),isoyuanhuadin(5),and yuanhuadin(6).Conclusion Compound 1 is a new compound.Compounds 1—6 exhibit the strong cytotoxicity on SK-BR-3 human breast cancer cells with the IC50values of 217.1,172.6,170.2,809.4,83.7,and 61.6 nmol/L,respectively,but show no effect on NCI-H1975 human lung cancer cells.