Dammarane-type saponins from leaves of Ziziphus spina-christi.

Phytochemical profiling of Ziziphus spina-christi leaves led to the characterization of 10 dammarane-type saponins and 12 phenolic compounds. Isolation was achieved by gel chromatography on Sephadex LH20, open column chromatography on silica gel, and semi-preparative HPLC with PDA and ELSD detectors. Structural characterization was performed by extensive 1D and 2D NMR, mass spectrometry, and by GC-MS of sugar derivatives. A biosynthetic pathway leading to three previously undescribed sapogenins is proposed. The saponin profiles in Z. spina-christi leaves of four different origins were compared by means of HPLC-ESIMS.