Anti-HIV protease triterpenoids from the acid hydrolysate of Panax ginseng

Three artificial triterpenoids, (20R)-20,25-epoxy-dammaran-2-en-6 alpha,12 beta-diol (1), (2OR)-20,25-epoxy-3-methyl-28-nordammaran-2-en-6 alpha,12 beta-diol (2) and isodehydroprotopanaxatriol (3), were isolated from an acidic hydrolysate of Panax ginseng C.A. Meyer, along with three known triterpenes, (20R)-panaxadiol (4),(20R)-panaxatriol (5) and oleanolic acid (6). Compounds 1-3 and 6 showed inhibitory activity against HIV-1 protease with IC50 of 10.5, 10.3, 12.3 and 6.3 mu M, respectively. The results indicated that acid treatment of Ginseng extract could produce diverse structures with interesting bioactivity. (C) 2008 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.