A chemical study on the steroidal glycosides from Atropa belladonna L. seeds

Eight steroidal glycosides of the spirostane type tentatively named atroposides A, B, C, D, E, F, G, and H (according to their increase in polarity) have been isolated from the methanolic extract of Atropa belladonna L. seeds by Sephadex gel filtration and column chromatography on silica gel impregnated with AgNO3. The structure of atroposides A, C, E, G has been elucidated as 3-O-alpha-D-galactopyranoside; 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside; 3-O-beta-D-glucopyranosyl (1-->2) -beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside; and 3-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside, each of (25R)-5 alpha-spirostane-3 beta-ol, respectively. The structure of atroposides B, D, F, and H has been elucidated as 3-O-beta-D-galactopyranoside; 3-O-beta-D-glucopyranosyl (1-->4)beta-D-galactopyranoside; 3-O-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside; 3-O-alpha-L-rhamnopyranosyl (1-->4)-B-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside, each of (25R)-spirost-5-en-3-b-0l, respectively.