Identification and characterisation of the phenolics of Ilex glabra L. Gray (Aquifoliaceae) leaves by liquid chromatography tandem mass spectrometry.

The phenolics of the leaves of Ilex glabra L. Gray (Aquifoliaceae) were investigated qualitatively by LC-MS(n). Thirty-two phenolics were detected and characterised on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra. All of them were extracted for the first time from this source and fifteen of them were not reported previously in nature. For the positive identification of phenolic glucosides by LC-MS(n) a series of authentic standards and experiments were carried out. This is the first report of a full characterisation of 3,4-dihydroxybenzoyl glucosides, 3,4-dihydroxybenzyl glucosides, 4-hydroxybenzoyl glucosides, chlorogenic acid glucosides and vanillic acid glucosides by LC-MS(2-4).