NMR and UPLC-qTOF-MS/MS characterisation of novel phenylethanol derivatives of phenylpropanoid glucosides from the leaves of strawberry (Fragaria x ananassa cv. Jonsok)

Phytochem Anal. 2009 Sep-Oct;20(5):353-64. doi: 10.1002/pca.1133.


Introduction: Strawberry (Fragaria x ananassa) is rich in polyphenols, particularly anthocyanins, flavonols, condensed tannins and ellagic tannins. In addition to the fruits, the leaves of strawberry also contain a wide range of phenolic compound classes, but have not been investigated to the same extent as the fruit.

Objective: To characterise a metabolite group present in the leaves of strawberry, that was not amenable for identification based on earlier information available in the literature.

Methodology: Methanolic extracts of strawberry leaves were analysed by UPLC-qTOF-MS/MS and iterative quantum mechanical NMR spectral analysis.

Results: The structures of phenylethanol derivatives of phenylpropanoid glucosides Eutigoside A ( F4) and its two isomeric forms 2-(4-hydroxyphenyl)ethyl-[6-O-(Z)-coumaroyl]-beta-D-glucopyranoside (F6) and 4-(2-hydroxyethyl)phenyl-[6-O-(E)-coumaroyl]-beta-D-glucopyranoside (F1) were resolved by NMR and UPLC-qTOF-MS/MS. In addition, two other derivatives of phenylpropanoid glucosides similar to Eutigoside A but possessing different phenolic acid moieties, namely Grayanoside A ( F5) and 2-(4-hydroxyphenyl)ethyl-[6-O-(E)-caffeoyl]-beta-D-glucopyranoside (F14), were similarly identified. Also, accurate characteristic coupling constants for the subunits are reported and their usefulness in structural analysis is highlighted.

Conclusion: Chemical analysis of the leaves of strawberry (Fragaria x ananassa cv. Jonsok) resulted in the identification of a compound class, phenylethanol derivatives of phenylpropanoid glycosides, not previously found in strawberry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caffeic Acids / chemistry*
  • Chromatography, High Pressure Liquid / methods
  • Coumarins / analysis*
  • Coumarins / chemistry*
  • Fragaria / chemistry*
  • Glucosides / analysis*
  • Glucosides / chemistry
  • Magnetic Resonance Spectroscopy / methods*
  • Methanol / chemistry
  • Phenols / chemistry
  • Phenylethyl Alcohol / analysis*
  • Phenylethyl Alcohol / chemistry
  • Plant Extracts / analysis
  • Plant Extracts / chemistry
  • Plant Leaves / chemistry*
  • Propanols / chemistry
  • Spectrometry, Mass, Electrospray Ionization / methods*


  • 2-(4-hydroxypheny)ethyl-(-O-(E)-caffeoryl)-b-D-glucopyranoside
  • Caffeic Acids
  • Coumarins
  • Glucosides
  • Phenols
  • Plant Extracts
  • Propanols
  • eutigoside A
  • Phenylethyl Alcohol
  • Methanol