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Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations
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Molecular mechanics (MM4) study of amines

Kuo-Hsiang Chen1, Jenn-Huei Lii, Yi Fan

  • 1Department of Chemistry, Center for Computational Chemistry, Chemistry Annex, University of Georgia, Athens, Georgia 30605-2526, USA.

Journal of Computational Chemistry
|May 9, 2007
PubMed
Summary

The MM4 force field now accurately models aliphatic amines, providing reliable molecular mechanics parameters. This extension improves predictions for vibrational spectra, moments of inertia, and heats of formation for amine compounds.

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In mass spectroscopy, amines undergo fragmentation to give parent ions with odd molecule weights. This observed mass spectrum follows the nitrogen rule; a molecule with an odd number of nitrogen atoms produces a molecular ion with an odd molecular weight. Amines undergo fragmentation through α cleavage, producing nitrogen-containing cations—iminium ions—and alkyl radicals. Mass spectra of aromatic and cyclic aliphatic amines exhibit strong molecular ion peaks, but acyclic aliphatic amines show...
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