新西兰牡荆苷等4种碳苷黄酮的电喷雾质谱裂解规律研究

目的:利用电喷雾质谱技术对新西兰牡荆苷、木犀草素-6-C-葡萄糖-8-C-木糖苷、槲皮素-6-C-葡萄糖苷和二氢槲皮素-6-C-葡萄糖苷4种碳苷黄酮的质谱裂解规律进行研究.方法:用电喷雾多级质谱(ESI-MSn)对该类化合物进行研究,并分别在正离子和负离子扫描模式下对其主要特征碎片离子进行解析.结果:负离子扫描模式下,主要发生糖环裂解,六碳糖碳苷主要产生脱去m/z 120,90的碎片峰,五碳糖碳苷主要产生脱去m/z 90,60的碎片峰,双糖碳苷主要产生连续脱去m/z120,90,60的碎片峰；正离子扫描模式下,主要发生糖羟基连续脱水,六碳糖碳苷产生脱去m/z 120的碎片峰,五碳糖碳苷产生脱去m/z 60的碎片峰.碳苷黄酮的负离子扫描模式比正离子扫描模式的质谱特征更明显.结论:分析了这4种碳苷黄酮的电喷雾多级质谱裂解规律,探讨了碳苷黄酮,特别是双糖碳苷黄酮质谱裂解规律,为碳苷黄酮的快速鉴别提供了参考.

Study on the Four Flavone-C-glycosides by Electrospray Ionization Tandem Mass Spectrometry

Objective: To study on the four flavone-C-glycosides which were vicenin-2, luteolin-6-C-glucopyranosyl-8-C-xylopyranoside, quercetin-6-C-glucopyranoside and dihydroquercetin-6-C-glucopyranoside by electrospray ionization tandem mass spectrometry (ESI-MSⁿ). Method: The samples were analyzed by ESI-MSⁿ under positive and negative ion models. Result: Under negative ion model, flavone-C-glycosides which had pentose substituent take place sugar bond cleavage and generate fragment ions (m/z 90 and 60), these which had hexose substituent generate fragment ions (m/z 120 and 90) and these which had two sugar substituents successively generate fragment ions (m/z 120, 90 and 60). Under positive ion model, flavone-C-glycosides take place dehydration,and these flavones which had pentose substituent take place sugar bond cleavage and generate fragment ions (m/z 60), these which had hexose substituent generate fragment ions (m/z 120). Conclusion: The ESI-MSⁿ methods for the identification of flavone-C-glycosides, especially which had two sugar substituents, were established.