Naslov
Dissociation energies of Cα–H bonds in amino acids – a re-examination

Autori
Hioe, Johnny ; Mosch, Marianne ; Smith, David M. ; Zipse, Hendrik

Izvornik
RSC Advances (2046-2069) 3 (2013); 12403-12408

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
C–H bond dissociation energies; amino acids; radical stability
(nd dissociation energies; amino acids; radical stability)

Sažetak
The Cα–H bond dissociation energies (BDE) in glycine and alanine peptide models have been assessed using selected theoretical methods from the G3 and, in part, G4 family. The BDE values (and thus the stability of the respective Cα peptide radicals) are shown to depend significantly on the level of theory, the size of the model system and the coverage of conformational space. For the largest dipeptide models chosen here, BDE(Cα–H) values of +363.8 kJ mol−1 (glycine) and +372.3 kJ mol−1 (alanine) have been obtained at G3B3 level. This reconfirms earlier findings that glycyl peptide radicals are more stable than radicals derived from alanine or any other amino acid carrying substituents at the Cα position.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA