Tirucallane triterpenoids from the stem bark of Araliopsis synopsis

Happi EN, Tcho AT, Sirri JC, et al. Tirucallane triterpenoids from the stem bark of Araliopsis synopsis. Phytochemistry Letters. 2012;5(3):423-426.Two new tirucallane triterpenoids, 21-methoxy-21,23-epoxy-tirucalla-7,24-dien-3 alpha-ol (1) and 21-methoxy-21,23-epoxy-tirucalla-7,24-diene-1 alpha,3 alpha-diol (2), together with thirteen known compounds were isolated from the CH2Cl2 extract of the stem bark of Araliopsis synopsis. The structures of the compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral (EI and ESI) data and comparison with previously known analogs. Compounds 1-10 were tested against bacteria, fungi and plant pathogen oomycetes by the paper disk agar diffusion assay resulting in missing to low activities corresponding with MICs > 1 mg/mL. However, compounds 5-10 exhibited high cytotoxic activity against the human Caucasian prostate adenocarcinoma cell PC-3 line, with IC50 8.5-12.5 mu M compared to the standard Doxorubicin with IC50 = 0.9 mu M, while compounds 1, 3 and 4 showed low activity. (C) 2012 Published by Elsevier B.V. on behalf of Phytochemical Society of Europe