山奈甲黄素-3,7-二-O-多取代黄酮苷的串联质谱研究

A Fragmentation Study of Kaempferide 3,7-Di-O-glycosides by Electrospray Ionization Tandem Mass Spectrometry

利用电喷雾串联质谱研究了几种从狗枣猕猴桃叶中提取得到的糖基取代山奈甲黄素的碎裂规律.结果表明,由于碎裂规律不同,3,7-二-O-取代山奈甲黄素能够和3-O或者7-O单取代山奈甲黄素区分:单取代山奈甲黄素主要失去取代糖基生成黄酮苷元的碎片,而3,7-二-O-取代黄酮主要失去某一处取代糖基生成相应的碎片离子([Y03]-和[Y07]-),而难观察到所有取代糖基都失去的黄酮苷元碎片离子.并且由于[Y03]-和[Y07]-离子的进一步碎裂方式不同,很容易将其区分开,从而确定不同糖基的取代位置.

A serious of new methoxylated flavonol including kaempferide mono-O-glycosides and kaempferide 3,7-di-O-glycosides from Actinidia kolomikta were studied by using electrospray ionization tandem mass spectrometry. The results indicated kaempferide mono-O and di-O have substantial difference in their fragmentation behaviors. Kaempferide mono-O-glycosides yielded abundant aglycone ion （[Y0]-） by loss of glycan residues,however,3,7-di-O-glycosides mostly generated [Y0 3]-and [Y0 7]-ions through removal of glycan residues substituted in C-7 and C-7 respectively,but little aglycone ion from loss of all substituted glycans. Furthermore,the glycosylation site could be easily determined because the [Y0 3]-and [Y0 7]-ions shown different fragmentation pathways.