| Abstract
| - Quantum mechanics methods have been applied to investigate the effects of the selective orientation of theside chains on the conformational features of cyclopropane analogues of phenylalanine. For this purpose, theconformational preferences of the N-acetyl-N‘-methylamide derivative of 1-aminocyclopropanecarboxylic acid(Ac3c) have been compared to those of two stereoisomers of 1-amino-2-phenylcyclopropanecarboxylic acid: (2S,3S)c3Phe and (2S,3R)c3Phe. Geometry and vibration frequencies were calculated by the HF, B3LYP, orMP2 methods using the 6-31G(d) basis set, whereas the energy was further evaluated using, in some cases,more sophisticated methods and larger basis sets. Solvent effects were modeled by the self-consistentpolarization continuum model with the HF/6-311G(d,p) method. The stereochemistry of the phenyl side chainlargely influences the specific backbone...side chain interactions, which in turn affect the stability of thedifferent conformations. Furthermore, results have been compared with recently published experimental data.
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