Antiproliferative activity of the diterpenes jatrophone and jatropholone and their derivatives.

The antiproliferative activity of the diterpenes jatropholone A and B, 16 semi-synthetic derivatives thereof, and that of jatrophone and its three derivatives was assessed on human cell cultures. The cells used comprised normal lung fibroblasts (MRC-5), gastric adenocarcinoma (AGS), leukemia (HL-60), lung cancer (SK-MES-1), and bladder carcinoma (J82). Jatropholone A ( 1) was inactive against all the tumor cell lines; however, its acetylation rendered a compound with antiproliferative activity. The epimeric jatropholone B ( 8) was active against all the cancer cell lines, and its derivatives presented different effects on the selected cell lines. While jatrophone ( 19) showed strong anticancer activity, its derivatives 9beta,13alpha-dihydroxyisabellione and 13alpha-hydroxy-9 beta-acetoxyisabellione were less active.