ABSTRACT
<p><b>OBJECTIVE</b>To study the immunosuppressive constituents from Tetraena mongolica.</p><p><b>METHOD</b>Chemical constituents were isolated and purified by repeated column chromatography( silica gel, Toyopearl HW40C and preparative HPLC). Their structures were elucidated on the basis of spectral data analysis. The MTT assay was applied to evaluate the isolated compounds on the inhibition effect of lymphocyte transformation.</p><p><b>RESULT</b>Six triterpenes were isolated and their structures were identified as follows: 3beta-hydroxy-11alpha, 12alpha:13beta,28-diepoxyoleanane(1), 3beta-(3, 4-dihydroxycinnamoyl)-erythrodi-ol(2), olean-28-al-3beta-yl-caffeate(3), erythrodiol (4), 12-oleanaen-3beta-caffeate(5), 3-O-(E) -coumaroylerythrodiol(6). Compound 24 exhibited the inhibition effects on lymphocyte transformation.</p><p><b>CONCLUSION</b>Compounds 1-6 were isolated from this plant for the first time, and compound 1 was a new nature product. Compound 2-4 showed significant immunosuppressive activity.</p>