Conformational Analysis of Tripeptide Models: The Influence of alpha,alpha-disubstitnted alpha-Amino Acids on the Secondary Structure. NMR and CD Investigations
The conformational properties of alpha,alpha-disubstituted alpha-amino acids are discussed on the basis of NMR, CD, X-ray, and molecular-mechanics studies on tripeptide models 1. It is shown that different disubstituted amino acids do not exert the same influence on secondary-structure formation. Thus, the choice of substituents allows the construction and stabilisation of different conformations of oligopeptide chains.