12-O-acetylphorbol-13-decanoate potently inhibits cytopathic effects of human immunodeficiency virus type 1 (HIV-1), without activation of protein kinase C

Through bioactivity-guided fractionation, eight phorbol di-eaters, includin g five new ones (1-5), were isolated from the seeds of Croton tiglium colle cted in Egypt, 12-O-Acetylphorbol-13-decanoate (6) and 12-O-decanoylphorbol -13-(2-methylbutyrate) (4) potently inhibited the HIV-l-induced cytopathic effect on MT-4 cells (IC100 values of 7.6 ng/ml and 7.81 mu g/ml, and CC0 v alues of 62.5 mu g/ml and 31.3 mu g/ml, respectively) without activating pr otein kinase C.