Hydrogen Rearrangement Rules: Computational MS/MS Fragmentation and Structure Elucidation Using MS-FINDER Software

Compound identification from accurate mass MS/MS spectra is a bottleneck for untargeted metabolomics. In this study, we propose nine rules of hydrogen rearrangement (HR) during bond cleavages in low-energy collision-induced dissociation (CID). These rules are based on the classic even-electron rule and cover heteroatoms and multistage fragmentation. We evaluated our HR rules by the statistics of MassBank MS/MS spectra in addition to enthalpy calculations, yielding three levels of computational MS/MS annotation: "resolved" (regular HR behavior following HR rules), "semiresolved" (irregular HR behavior), and "formula-assigned" (lacking structure assignment). With this nomenclature, 78.4% of a total of 18506…

• AH
  American Heart Association

  Award: 15SDG25760020
• MO
  Ministry of Education, Culture, Sports, Science and Technology

  Award: 15K01812
• JS
  Japan Society for the Promotion of Science

  Award: 15H05897
• JS
  Japan Science and Technology Agency
• R
  RIKEN
• NH
  National Heart, Lung, and Blood Institute

  Award: 2R01HL091357-05
• DO
  Division of Chemical, Bioengineering, Environmental, and Transport Systems

  Award: CBET 1438211
• DO
  Division of Molecular and Cellular Biosciences

  Award: MCB 1139644
• CR
  Core Research for Evolutional Science and Technology
• NB
  National Bioscience Database Center