pentacyclic triterpenes in euphorbia microsciadia with their t-cell proliferation activity

the ethyl acetate partition of dried methanolic extract of aerial parts of euphorbia microsciadia (euphorbiaceae) afforded three pentacyclic triterpenes, betulinic acid (1) from lupane type, oleanolic acid (2) from oleane type and ursolic acid (3) from ursane type triterpenes that are reported for the first time in this plant. these three compounds were structurally compared through their mass fragmentation pattern, nuclear magnetic resonance (nmr) data and their biologic immunomodulatory effects. the structures of the isolated compounds were elucidated by 13c- and 1h-nmr as well as 2d-nmr, ir and by the aid of mass fragmentation pattern and comparing with the literature. after running t-cell proliferation assay, oleanolic acid stimulated proliferation of t-cells at lower concentration 0.5 µg/ml, while betulinic acid and ursolic acid showed inhibitory activity against t-cell proliferation with ic50- value > 50 µg/ml and 3.01 ± 0.47 µg/ml, respectively.