Differentiation of common diastereoisomeric ursane-type triterpenoids by high-performance liquid chromatography/tandem mass spectrometry
Article first published online: 18 APR 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 25, Issue 10, pages 1349–1355, 30 May 2011
How to Cite
Gao, J., Shi, J., Lu, X., Sun, C. and Pan, Y. (2011), Differentiation of common diastereoisomeric ursane-type triterpenoids by high-performance liquid chromatography/tandem mass spectrometry. Rapid Commun. Mass Spectrom., 25: 1349–1355. doi: 10.1002/rcm.4978
- Issue published online: 18 APR 2011
- Article first published online: 18 APR 2011
- Manuscript Accepted: 9 FEB 2011
- Manuscript Revised: 8 FEB 2011
- Manuscript Received: 8 DEC 2010
- National Natural Science Foundation of China. Grant Number: 20772109
A rapid and stable method consisting of high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry was established for the identification and differentiation of common diastereoisomeric ursane-type triterpenoids at the C-3 position. Two characteristic fragment ions, [M–H–H2O–CO2]– and [M–H–H2O–HCOOH]–, exhibited significant stereochemical effects and were utilized to distinguish 3-OH epimers. Based on reference standards, the abundance of the fragment ion [M–H–H2O–HCOOH]– in 3β-OH compounds in the MS3 experiment was dramatically higher compared to [M–H–H2O–CO2]–; however, for 3α-OH compounds, the product ion [M–H–H2O–CO2]– was noted to be higher than [M–H–H2O–HCOOH]–. Energy-resolved mass spectrometric experiments were carried out to support the differentiation of these diastereoisomeric triterpenoids at the C-3 position. Using this method, a total of nine ursane-type triterpenoids from a plant crude extract, including four pairs of epimers at the C-3 position, were identified and distinguished rapidly. Furthermore, offline Fourier transform ion cyclotron resonance tandem mass spectrometry was also performed to assign accurate elemental compositions. Copyright © 2011 John Wiley & Sons, Ltd.