Transformation of naturally-occurring 1,9-trans-9,5-cis sweroside to all trans sweroside during acetylation of sweroside aglycone

M M Horn; S E Drewes; N J Brown; O Q Munro; J J Meyer; A D Mathekga

doi:10.1016/s0031-9422(00)00460-x

Transformation of naturally-occurring 1,9-trans-9,5-cis sweroside to all trans sweroside during acetylation of sweroside aglycone

Phytochemistry. 2001 May;57(1):51-6. doi: 10.1016/s0031-9422(00)00460-x.

Authors

M M Horn¹, S E Drewes, N J Brown, O Q Munro, J J Meyer, A D Mathekga

Affiliation

¹ School of Chemical and Physical Sciences, University of Natal, Scottsville, South Africa.

PMID: 11336260
DOI: 10.1016/s0031-9422(00)00460-x

Abstract

From the rootstock of Scabiosa columbria L. loganin and sweroside were isolated. Sweroside showed moderate antibacterial activity. Pure sweroside was converted to the sweroside aglycone 1-acetoxy derivative (DABCO/Ac2O) after hydrolysis of the glucose unit. X-ray crystallography of the monoacetate showed unambiguously that it had been transformed to a new seco-iridoid having the novel trans diaxial configuration for the protons on C-1, C-9 and C-5. The mechanism for the rearrangement is discussed.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acetylation
Biotransformation
Crystallography, X-Ray
Glucosides / biosynthesis*
Glucosides / chemistry
Iridoid Glucosides
Iridoids*
Magnetic Resonance Spectroscopy
Pyrans / chemistry
Spectrometry, Mass, Electrospray Ionization

Substances

Glucosides
Iridoid Glucosides
Iridoids
Pyrans
sweroside