A new jujubogenin saponin was isolated from the stems of Colubrina retusa a
nd identified as jujubogenin 3-O-alpha-L-arabinofuranosyl (1-->2)-[3-O-(tra
ns)-p-coumaroyl-beta-D-glucopyranosyl (1-->3)]-alpha-L-arabinopyranoside (4
) on the basis of chemical and spectroscopic data. The antimycobacterial ac
tivity expressed as minimum inhibitory concentration (MIC) for compound 4 w
as 10 mu g/mL.