苦参中黄酮类化合物的电喷雾质谱研究

采用电喷雾多级串联质谱对苦参中黄酮类化合物二氢黄酮及二氢黄酮醇类化合物的特征质谱行为进行了研究.实验结果表明,两类化合物在电喷雾多级串联质谱条件下均可以在C环发生开环断裂,但断裂的位点不同;两类化合物生成的碎片离子也有很大差异,提出了由二氢黄酮醇类化合物C环上3位连接的-OH所诱发的不同反应过程的质谱碎裂机理.

Studies on Flavonoids from Sophora Flavescens Ait Using ESI-MSn

Two kinds of flavonoids from Sophora Flavecens Aits, dihydroflavonoids and dihydroflavonols, were studied by using electrospray ionization tandem mass spectrometry(ESI-MSn). M-H]- of these two kinds of flavonoids were observed in the negative ion mode under ESI conditions, which provided us the molecular weights of them. Cross-ring reactions, arisen from MS2 spectra of both dihydroflavonoids and dihydroflavonols, gave the fragment ions by the loss of neutral species. The differences of their cleavage positions were then proposed, dihydroflavonoids cleave at C2—O bond and C4—C10 bond, but dihydroflavonols cleave at C2—O bond and C3—C4 bond. The loss of neutral species from dihydroflavonoids and dihydroflavonols were also discussed, the former were several relative big neutral species, while the latter were some small species, such as CO, CO2, H2O and B-ring. The differences between dihydroflavonoids and dihydroflavonols were mainly arisen by hydroxy group at C-3 of the C-ring, which were the characteristic for dihydroflavonoids and dihydroflavonols under the ESI-MS n conditions.