13- PHYTOCHEMICAL STUDY OF FLOWERS AND LATEX OF CRYPTOSTEGIA GRANDIFLORA R.BR. CULTIVATED

IN EGYPT

 

S. M. El Zalabani, E. A. Abdel Sattar, F. I. Fathy and N. G. Shehab

Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt

Received:19-5-2004

Accepted:14-7-2004

 

Abstract:

From the flowers of Cryptostegia grandiflora R.Br. two cardenolides oleandrigenin (1) and gitoxigenin (2), as well as, two flavonoid glycosides hyperoside (5) and astragalin (6), and their aglycones quercetin (4) and kaempferol (3) were isolated. While, b-amyrin (7), lupeol (8), a-amyrin (9), b-sitosterol (10) and b-sitosterol–3-O-b-D-glucoside (11), in addition to a phenolic glucoside 2,4,6-trihydroxy benzophenone-2-O-b-D-glucopyranoside (12) were isolated from the latex of fresh unripe fruits. Characterization of the isolated compounds was achieved through physical, chemical, chromatographic and spectral analyses, as well as, by comparison with available authentic samples. All the aforementioned compounds except 1, 2 and 12 were, for the first time, isolated from the titled plant. The total flavonoid content of the flowers was colorimetrically determined and amounted to 3.25 %. In addition, the lipoidal composition of the flowers and latex was qualitatively and quantitatively investigated using different chromatographic techniques (TLC and GLC).