Pregnane glycosides from Gymnema sylvestre

Abstract

Three pregnane glycosides, gymnepregoside F (1), 12-O-(E)-cinnamoylgymnepregoside F (2), and stephanoside I (3) were isolated from the leaves of Gymnema sylvestre (Retz.) R.Br. ex Schult. Their structures were identified on the basis of spectroscopic evidences and in comparison with those reported in the literature. All these compounds were reported from this genus Gymnema for the first time.

Five New Pregnane Glycosides from Gymnema sylvestre and Their α-Glucosidase and α-Amylase Inhibitory Activities

“…The 1 H and 13 C-NMR spectra of 2 exhibited a pregnane aglycone, one tigloyl unit, and three sugar units (Table 1). In addition, the NMR data of 2 were similar to those of gymsyloside A ( 1 The aglycone of 1 was supposed to have the same configurations as those of gymnepregoside F and 12-O-(E)-cinnamoylgymnepregoside F from G. sylvestre [12], biogenetic derivatives of 1 at C-3, C-8, C-12, C-14, C-17, and C-20. In addition, the alkaline hydrolysis of 1 gave sarcostin, ((20S)-3β,8β,12β,14β,17β,20-hexahydroxypregn-5-ene) [13].…”

Lignans from Gymnema Sylvestre

“…In previous papers [1][2][3][4] we have reported the isolation and structural elucidation of pregnane glycosides and oleanane saponins from Gymnema sylvestre. In continuation of our chemical investigation on G. sylvestre species, this paper describes the isolation and structural elucidation of seven known lignans, tortoside A of Ecology and Biological Resources, VAST.…”