Naslov
GAS PHASE H/D EXCHANGE OF SODIATED AMINO ACIDS: WHY DO WE SEE ZWITTERIONS?

Autori
Rožman, Marko ; Bertoša, Branimir ; Klasinc, Leo ; Srzić, Dunja

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
The 2005 Younger European Chemists' Conference / - Brno : SET for Europe, 2005

Skup
The 2005 Younger European Chemists' Conference

Mjesto i datum
Brno, Češka Republika, 30.08.2005. - 04.09.2005

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
H/D exchange; sodiated amino acids; reaction mechanism

Sažetak
The gas phase interaction of sodiated amino acids and sodiated amino acid methyl esters with various deuterium donors is investigated by combining results of H/D exchange reactions with those from density functional theory and molecular dynamics calculations. Discrepancy between experimentally and theoretically obtained structures for sodium cationized amino acids is explained by deuterium donor caused perturbation of the most stable amino acid conformation. Detailed study of H/D exchange mechanism on sodiated amino acids shows that prior to H/D exchange reaction there is a quasi energy free transition from a charge solvated to zwitterionic structure of the amino acid. Although the computation refers to the system AlaNa+ and D2O, this mechanism applies to all amino acids, except those where a functional side chain group takes part in the perturbation process. The suggested perturbation mechanism applies also for other deuterium donors such as CD3OD or even ND3 and indicates that a single water molecule suffices to convert the sodiated amino acid from charge solvated to zwitterionic form.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA