Cytotoxic pregnane glycosides from (Forssk.).

(Forssk.) is a medicinal succulent plant belonging to the family Apocynaceae. The phytochemical examination of methanolic extract resulted in isolation of three unique new pregnane glycosides, quadrangulosides G-I (), their structures were elucidated utilising 1D, 2D NMR and ESI MS spectral studies.

Quadrangulosides A-F: new pregnane glycosides from .

The phytochemical investigation of aerial parts yielded six new pregnane glycosides, quadrangulosides A-F (1-6), in addition to nine known pregnane glycosides and three known flavone glycosides. Structures of isolated phyto-constituents were elucidated spectroscopic 1D-, 2D-NMR and spectrometric ESI-MS spectra.