Mulroney B, Barrie Peel J, Traeger J C
Department of Chemistry, La Trobe University, Bundoora, Victoria 3083, Australia.
J Mass Spectrom. 1999 Aug;34(8):856-71. doi: 10.1002/(SICI)1096-9888(199908)34:8<856::AID-JMS841>3.0.CO;2-8.
Molecular orbital calculations were used to investigate the fragmentation of deprotonated glucopyranosyl disaccharides. Based on data from collisional activation and isotopic labeling experiments, fragmentation mechanisms are proposed, with calculated transition states being used to study the energetics of fragmentation. The calculations suggest that deprotonation at the C(2) hydroxyl of the non-reducing ring, following ring opening, may be important for disaccharide fragmentation. It is also shown that the stereochemistry at the 2-position of the non-reducing ring may have a significant effect on disaccharide fragmentation, particularly with regard to determination of the anomeric configuration.
利用分子轨道计算来研究去质子化吡喃葡萄糖基二糖的碎片化过程。基于碰撞活化和同位素标记实验的数据，提出了碎片化机制，并使用计算得到的过渡态来研究碎片化的能量学。计算结果表明，在开环后，非还原环的C(2)羟基去质子化可能对二糖碎片化很重要。还表明，非还原环2位的立体化学可能对二糖碎片化有显著影响，特别是在确定异头构型方面。
