RESUMO
Chloroform-acetone extract of the aerial parts of Euphorbia aellenii Rech. f. (Euphorbiaceae) was investigated for its diterpenoidal constituents. This led to the isolation of two new and one known cyclomyrsinol-type diterpenes 1-3. The structures were elucidated on the basis of 1D and 2D (1)H and (13)C NMR techniques, and in vitro immunomodulatory activity was evaluated by standard proliferation of human peripheral blood lymphocytes. Results showed that all the three compounds were found to inhibit lymphocyte proliferation significantly (p < 0.05) at 50 µg/ml concentration. Among them, compound 2 showed more activity against phytohemagglutinin-activated T-cell proliferation with an IC(50) of 40.4 ± 9.35 µg/ml.
Assuntos
Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Euphorbia/química , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Diterpenos/sangue , Diterpenos/química , Humanos , Fatores Imunológicos/sangue , Fatores Imunológicos/química , Irã (Geográfico) , Linfócitos/efeitos dos fármacos , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
The cytotoxic chloroform fraction of Euphorbia aellenii afforded two cycloartane type triterpenes-cycloart-25-en-3ß,24-diol (1) and 24-methylene-cycloartan-3ß-ol (2)-for the first time from this plant. Preparation of cycloartane derivatives, 3ß, 24-O-diacetyl-cycloart-25-en as compound 3 and 3ß-O-acetyl-24-methylene-cycloartan (4) were conducted by acetylating of 1 and 2, respectively. The structures of the isolated compounds were elucidated by spectroscopic methods and their activities evaluated by proliferation assay on human peripheral blood lymphocytes (PBLs). Comparing the results suggested that anti-proliferation effect of these compounds on PBLs might be due to the presence of free 3-OH group while masking the free OH groups by acetylation, could induce proliferation activity.
