new tigliane-type diterpenoids from euphorbia aellenii rech. f. with immunomodulatory activity

the cytotoxic chloroform fraction of euphorbia aellenii rech. f. (euphorbiaceae) afforded two new phorbol diterpenoids: 4-deoxy-4α-phorbol-12-(2,3-dimethyl) butyrate-13-isobutyrate and 17-hydroxy-4-deoxy-4α-phorbol-12-(2,3-dimethyl) butyrate-13-isobutyrate. their structures were elucidated by nmr and other spectroscopic methods. the immunomodulating potentials of the isolated compounds were tested using standard proliferation and chemiluminescence assays. compound 2 showed moderate inhibitory activity against both t-cell proliferation and reactive oxygen species (ros) production in whole blood with ic50 of 14.0 ± 0.57 and 44.1 ± 3.8 μg/ml, respectively, while compound 1 was relatively inactive with ic50 >50 μg/ml for t-cell proliferation, and >100 μg/ml for ros.