Major saponins from the starfish asterias forbesi complete structures by nmr methods
Findlay, J.A.; Jaseja, M.; Burnell, D.J.; Brisson J R.
Canadian Journal of Chemistry 65(6): 1384-1391
1987
ISSN/ISBN: 0008-4042 Accession: 005845745
The structures of the two major saponins isolated from the starfish Asterias forbesi have been deduced totally by nuclear magnetic resonance methods applied to the undegraded molecules. The structure of forbeside, A, 6.alpha.-O-{.beta.-D-galactopyranosyl-(1.fwdarw.3)-.beta.-D-fucopyranosyl-(1.fwdarw.2)-.beta.-D-galactopyranosyl-(1.fwdarw.4)-[.beta.-D-quinovopyranosyl-(1.fwdarw.2)]-.beta.-D-xylopyranosyl-(1.fwdarw.3)-.beta.-D-quinovopyranosyl}-20-hydroxy-23-oxo-5.alpha.-cholest-9(11)-en-3.beta.-yl sodium sulfate, was deduced principally from 1H 2D-COSY, J-resolved, nuclear Overhauser enhancement and selected decoupling experiments. The structure of forbeside B,6.alpha.-O-{.beta.-D-quinovopyranosyl-(1.fwdarw.2)-.beta.-D-galactopyranosyl-(1.fwdarw.4)-[.beta.-D-quinovopyranosyl-(1.fwdarw.2)]-.beta.-D-xylopyranosyl-(1.fwdarw.3)-.beta.-D-quinovopyranosyl}-20-hydroxy-23-oxo-5.alpha.-cholest-9(11)-en-3.beta.-yl sodium sulfate, was deduced principally from 2D-COSY, HCORR, RECSY, and NOESY experiments.