电喷雾质谱法研究4种青蒿素类药物的质谱裂解特征

采用电喷雾-飞行时间质谱法(ESI-TOF MS)在正离子检测方式下，以注射泵直接进样的方式对4种青蒿素类药物进行碰撞诱导解离(CID)研究，获得各化合物的质谱碎片信息。以准分子离子[M+Na]⁺作为内标物，对碎片离子进行准确质量测定，确认这些碎片离子的元素组成，探讨该类化合物的质谱裂解途径。通过比较各化合物结构和质谱裂解途径的异同点，发现青蒿素类药物主要通过O-O及C-O键发生裂解，生成脱H₂O、CO、HCOOH和CH₃COOH的碎片离子，其中m/z 261和m/z 163为青蒿素类衍生物特有的碎片离子，这些特征将有助于青蒿素类化合物的结构解析。

Study of Fragmentation Behavior for 4 Artemisinins by Electrospray Ionization Mass Spectrometry

To investigate the fragmentation behavior of artemisinins, 4 artemisinins were analyzed using electrospray ionization/time of flight mass spectrometry (ESI-TOF MS) by collision induced dissociation (CID). The samples were infused into the ion source with a syringe pump, and mass spectrometry was operated in the positive ion mode. The mass spectra was obtained mainly by analyzing the fragments of the four compounds. The quasi-molecular ion [M+Na]⁺ was selected as internal reference ion for collection．The accurate masses and elemental compositions of the fragment ions were determined．The proposed fragmentation patterns of the mass spectra were explained. The mass spectra and structures of 4 artemisinins were compared with each other, it was observed that artemisinins mainly fragmented on O-O and C-O, and gave characteristic fragment ions by the neutral loss of H₂O,CO,HCOOH and CH₃COOH. The common fragment ions of m/z 261 and m/z 163 were also found in artemisinin derivatives. These characteristics can be used for future structures elucidation in studies of artemisinins．