New 3-O-acyl betulinic acids from Strychnos vanprukii Craib
Quyet Chien Nguyen1, Van Hung Nguyen, Bernard D Santarsiero
1Institute of Chemistry, National Center for Science and Technology, Nghia Do, Tu Liem, Hanoi, Vietnam.
Abstract:
Three new betulinic acid derivatives, 3beta-O-trans-feruloylbetulinic acid (1), 3beta-O-cis-feruloylbetulinic acid (2), and 3beta-O-cis-coumaroylbetulinic acid (4), along with two known triterpenes, 3beta-O-trans-coumaroylbetulinic acid (3) and ursolic acid (6) were isolated from the leaves and twigs of Strychnos vanprukiiCraib. All isolates showed moderate anti-HIV activity with IC50 values ranging from 3 to 7 microg/mL (5 to 15 microM) in an indicator cell line for HIV infectivity. The structures of the new isolates were elucidated by spectroscopic techniques including 1D and 2D NMR spectroscopy. In addition, the structure of 1 was confirmed by X-ray crystallography.
