Mechanism of gas-phase aldose-ketose isomerization: A study using tandem mass spectrometry and theoretical calculations.
Fast-atom bombardment tandem mass spectrometry and the semiempirical molecular orbital method were used to investigate the mechanism of gas-phase aldose-ketose isomerization process in lithiated 1,3 linked disaccharide isomers. Both the 1,3 hydrogen shift and hydride transfer mechanisms were investigated. Our experimental and theoretical calculations support the latter. The hydride transfer mechanism in these lithium-coordrnated systems is similar to the xylose isomerase catalyzed aldose-ketose isomerization.
Department of Chemistry, University of California, 94720, Berkeley, CA, USA.
Y J
YJ
Zheng
A
A
Staempfli
J A
JA
Leary