Saponin and Sapogenol. XXXV. Chemical Constituents of Astragali Radix, the Root of Astragalus membranaceus BUNGE. (2). Astragalosides I, II and IV, Acetylastragaloside I and Isoastragalosides I and II
Twelve triterpene-oligoglycosides were isolated from the glycosidic constituents of Astragali Radix, the root of Korean Astragalus membranaceus BUNGE. (Leguminosae). They were acetylastragaloside I (3), isoastragalosides I (5) and II (7), astragalosides I (4,major), II (6), III, IV (8), V, VI and VII, which contain a 9,19-cyclolanostane cycloastragenol (1) as the aglycone, and astragaloside VIII and soyasaponin I (9), which possess an oleanene-type aglycone, soyasapogenol B. By means of chemical degradations, which included a selective cleavage method for the glucuronide linkage, and ^<13>C-NMR examinations, the structure of astragaloside IV was elucidated as 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol (8). In addition, the structures of five acetyl derivatives of 8 : acetylastragaloside I, astragaloside I, isoastragaloside I, astragaloside II and isoastragaloside II, were elucidated as 3-O-β-(2', 3', 4'-tri-O-acetyl)-D-xylopyranosyl- (3), 3-O-β-(2', 3'-di-O-acetyl)-D-xylopyranosyl- (4), 3-O-β-(2', 4'-di-O-acetyl)-D-xylopyranosyl- (5), 3-O-β-(2'-O-acetyl)-D-xylopyranosyl- (6) and 3-O-β-(3'-O-acetyl)-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol (7), respectively.
- Chem. Pharm. Bull.
Chem. Pharm. Bull. 31, 698-708, 1983