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A set of two diastereomers of cyanogenic glycosides from Passiflora quadrangularis
Daisuke Saeki1, Takeshi Yamada, Tetsuya Kajimoto
1Osaka University of Pharmaceutical Sciences, 4-20-1, Nasahara, Takatsuki, Osaka 569-1094, Japan.
Abstract:
A set of two diastereomers of phenylcyano glycosides, (7S)- and (7R)-phenylcyanomethyl 1'-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (1, 2), were isolated from the methanol extract of dried vines of P. quadrangularis. The absolute configurations of the benzylic methine centers were determined mainly by the comparison of 13C NMR spectra of these compounds, prunasin (3) and sambunigrin (4), of which the last two cyanoglycosides are known to have (R)- and (S)-configurations, respectively.
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