Steroid glycosides ofNicotiana tabacum seeds I. The structures of nicotianosides A, B, and E

Two steroid glycosides of the spirostan series — nicotianosides A and B — and one glycoside of the furostan series — nicotianoside E — have been isolated from the seeds ofNicotiana tabacum L. Nicotianoside A is (25S)-5-spirostan-3-ol 3-O--D-glucopyranoside, nicotianoside B is (25S)-5-spirostan-3-ol 3-O-O--L-rhamnopyranosyl-(12)-gb-D-glucopyranoside], and nicotianoside E is (25S)-5-furostan-3,22,26-triol 26-O--glucopyranoside 3-O-O--L-rhamnopyranosyl-(12)--D-glucopyranoside].Institute of Genetics, Academy of Sciences of the Republic of Moldava, Kishinev, ul. Lesnaya, 20. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 737–742, November–December, 1994.