Dammarane and Ceanothane Triterpenes from Zizyphus glabrata

From the leaves of Zizyphus glabrata, a new dammarane-type triterpene, pseudojujubogenin -3-O-β-D-glucopyranoside, along with the known ceanothane triterpenes, granulosic acid, ceanothic acid and daucosterol were isolated. The structures of the compounds were fully characterized by detailed NMR investigations including 1 H and 13 C NMR, HSQC, COSY, HMBC and NOESY experiments. In addition, the dammarane glycoside was tested for its potential to inhibit various bacteria and was found to possess significant bactericidal activity. The 1 H, 13 C and full 2D-NMR data on granulosic acid has also been presented. This is the first report on the chemical constituents of the leaves of Z. glabrata.