Lopes Norberto P, Stark Christian B W, Hong Hui, Gates Paul J, Staunton James
University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge CB2 1EW, UK.
Rapid Commun Mass Spectrom. 2002;16(5):414-20. doi: 10.1002/rcm.592.
Monensin A and B were studied by electrospray ionisation tandem mass spectrometry (ESI-MS/MS) and the fragment ions were confirmed by accurate-mass measurements. Analyses were performed on both a quadrupole time-of-flight (QTOF) and a Fourier-transform ion cyclotron resonance (FTICR) mass spectrometer. The analysis revealed that fragment ions were produced by Grob-Wharton fragmentations and pericyclic rearrangements in addition to various simple neutral losses. A study of the protonated and sodiated sodium salt revealed different fragmentation pathways for these species, thus complementary structural information could be gained. A complete fragmentation pathway of monensin A and B protonated sodium salt [(M-H+Na)+H])+) and sodiated sodium salt (M-H+Na)+Na is proposed. MS(3) analysis confirmed the separate fragmentation pathways.
通过电喷雾电离串联质谱法（ESI-MS/MS）对莫能菌素A和B进行了研究，并通过精确质量测量对碎片离子进行了确认。在四极杆飞行时间（QTOF）质谱仪和傅里叶变换离子回旋共振（FTICR）质谱仪上均进行了分析。分析表明，除了各种简单的中性损失外，碎片离子是由格罗布-沃顿裂解和周环重排产生的。对质子化和钠化钠盐的研究揭示了这些物种不同的裂解途径，因此可以获得互补的结构信息。提出了莫能菌素A和B质子化钠盐[（M-H+Na）+H])+)和钠化钠盐（M-H+Na）+Na的完整裂解途径。MS(3)分析证实了不同的裂解途径。
