New phenylethanoid glycosides from Veronica pectinata var. glandulosa and their free radical scavenging activities


Saracoglu I., HARPUT U., INOUE M., OGIHARA Y.

CHEMICAL & PHARMACEUTICAL BULLETIN, vol.50, no.5, pp.665-668, 2002 (Peer-Reviewed Journal) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 50 Issue: 5
  • Publication Date: 2002
  • Doi Number: 10.1248/cpb.50.665
  • Journal Name: CHEMICAL & PHARMACEUTICAL BULLETIN
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.665-668
  • Keywords: Veronica pectinata var. glandulosa, Scrophulariaceae, phenylethanoid glycoside, antioxidant, DPPH, IRIDOID GLUCOSIDES, ANAGALLIS-AQUATICA, PLANTS

Abstract

A known phenylethanoid glycoside, ehrenoside (1), was isolated together with three new phenylethanoid glycosides, verpectoside A (2), B (3) and C (4) from the aerial parts of Veronica pectinata var. glandulosa. On the basis of spectral analysis (UV, FAB-MS, H-1-, C-13- and 2D-NMR), compounds 2-4 were determined to be 2-(3,4-dihydroxyphenyl)ethyl-O-alpha-L-arabinopyranosyl-(1 -->2)-[alpha-L-rhamnopyranosyl-(1-->3)]-(4-O-trans-feruloyl)-beta-D-glucopyranoside, 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-glucopyranosyl-(1-->2)- [alpha-L-rhamnopyranosyl-(1-->3)] (4-O-trans-caffeoyl)-beta-D-glucopyranoside and 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-glucopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->3)](4-O-trans-feruloyl)-beta-D-glucopyranoside, respectively. Isolated phenylethanoid glycosides exhibited potent radical scavenging activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical.