Two new pregnane glycoside diesters from Caralluma russeliana

Abstract

Two new pregnane glycoside diesters, 1 and 2, in addition to two triterpenoids, 3 and 4, and two sterols, 5 and 6 were isolated and identified from Caralluma russeliana (family Asclepiadaceae). The new pregnane glycosides, 14β-benzoyloxy-15β-isovaleroyloxy-16α-hydroxypregn-20-on-3-O-[β-D-3-O-methyl-6-deoxyoleandrosopyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside] (1) and 14β-isovaleroyloxy-15β-benzoyloxy-16α-hydroxypregn-20-on-3-O-[β-D-3-O-methyl-6-deoxyoleandrosopyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-β-D-cymaropyranoside] (2), are different from those isolated previously from the same species in the sugar moiety, in being diester, in being 20-one and in being 5,6 saturated by hydrogen. The isolated compounds were identified on the basis of spectral data.

Keywords:

• Caralluma russeliana
• pregnane glycoside esters
• 3-O-methyl-6-deoxyoleandrose
• cymarose

Acknowledgements

The authors are indebted to the Chemistry B.Sc. students Abdullah M. Eidan and Adnan W. Attayari, for helping in preparation of plant material, and to Prof. Dr. Abdulaziz Faied, Botany Department, Faculty of Science, King Abdulaziz University, for the botanical identification.