Dammarane and Ceanothane Triterpenes from Zizyphus glabrata

Abstract

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 1H and 13C 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 1H, 13C 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.