table of contents
Four compounds ß-sitosterol, ß-sitosterol-3-O-ß-D-glucopyranoside, ursolic acid and 4',5,6-trihydroxy-3', 7…
Extraction and Isolation
The air-dried aerial parts of cultivated S. khuzistanica (1 kg) was crushed and extracted with CH2Cl2 (3 x 3 liters) at room temperature for 6 days. The CH2Cl2 extracts were combined and concentrated in vacuo to yield a gummy extract. This residue treated with MeOH to remove waxy compounds.
The MeOH soluble portion (33.2 g) was subjected to a silica gel column chromatography (70–230 mesh, 800 g) with a gradient of hexane–EtOAc and then EtOAc–MeOH as eluent. Eight fractions were collected according to TLC analysis. The fraction of hexane–EtOAc (75:25) was subjected to another column chromatography using hexane–EtOAc (10:1) as the eluent. After recrystallization from MeOH, we obtained 75 mg of compound (1). The fraction of hexane–EtOAc (70:30) was rechromatographed over silica gel and eluted with hexane–EtOAc (9:1) to give 150 mg of compound (2). The fraction of hexane–EtOAc (60:40) was separated on another column chromatography and eluted with hexane–EtOAc (9:1) to give 270 mg of compound (3). From the fraction of EtOAc–MeOH (20:1), crude crystals were obtained, which gave after recrystallization from pyridine/MeOH 40 mg of pure compound (4).
rating: 0.00 from 0 votes | updated on: 20 Dec 2007 | views: 6439 |