Publication Date:
2011-01-22
Description:
Two new C 22 -steroidal lactone glycosides, ypsilactosides A ( 1 ) and B ( 2 ), were isolated from the EtOH extract of the whole plant of Ypsilandra thibetica. Their structures were established as (3 β ,5 α ,16 β ,20 S )-3,16-dihydroxy-6-oxopregnane-20-carboxylic acid γ -lactone 3-( β - D -glucopyranoside) ( 1 ) and (3 β ,16 β )-3,16-dihydroxypregna-5,20-diene-20-carboxylic acid γ -lactone 3-{ O - α - L -rhamnopyranosyl-(1→4)- O - α - L -rhamnopyranosyl-(1→4)- O -[ α - L -rhamnopyranosyl-(1→2)]- β - D -glucopyranoside} ( 2 ) on the basis of extensive spectroscopic analyses and chemical degradations.
Print ISSN:
0018-019X
Electronic ISSN:
1522-2675
Topics:
Chemistry and Pharmacology