An exhaustive conformational analysis of N-formyl-l-tyrosinamide using a genetic algorithm for multimodal search

Abstract

This work reports a detailed conformational study on N-formyl-L-tyrosinamide diamide system through genetic algorithm based on multiniche crowding technique. We tried to evaluate the effect of the OH hydroxyl substitution of the benzene ring on the adopted folds by comparing them with those found previously for the N-formyl-L-phenylalaninamide. Among the 26 and 28 conformations detected for both systems N-formyl-Ltyrosinamide and N-formyl-L-phenylalaninamide successively, 19 conformations have similar geometrical structures (identical backbones and side-chain orientations). The comparison of 19 common conformation geometries of both systems revealed nearly perfect linear adjustments with R 2 values of 0.9997, 0.9996, 0.9998, and 0.9996 for the dihedral angles 4, j, c 1 , and c 2 successively. This work also includes a comparison between theoretical calculations and experimental results of X-ray crystallography and nuclear magnetic resonance spectroscopy extracted from protein data bank.