Estimation on the intramolecular 10‐membered ring NH···OC hydrogen‐bonding energies in glycine and alanine peptides

摘要: Computation of accurate intramolecular hydrogen-bonding energies for peptides is great importance in understanding the conformational stabilities and developing a more force field proteins. We have proposed method to determine seven-membered ring N-H...O=C glycine alanine peptides. In this article, further applied evaluate 10-membered The optimal structures hydrogen bonds tripetide molecules are obtained at MP2 level with 6-31G(d), 6-31G(d,p), 6-31+G(d,p) basis sets. then evaluated based on our MP2/6-311++G(3df,2p) set superposition error correction. calculated be range -6.84 -7.66, -4.44 -4.98, -6.95 -7.88 kcal/mol. also estimate individual intermolecular dimers amino-acetaldehyde, 2-amino-acetamide, formamide, oxalamide, each dimer having two identical bonds. According method, four -1.77, -1.67, -6.35, -4.82 kcal/mol MP2/6-311++G(d,p) level, which good agreement values -1.84, -1.72, -6.23, -4.93 predicted by supermolecular method.