Competing reactions of disulphides and hydroxyl anion – QM study

Martin Krupička, Dominik Marx

Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany

Disulphide moiety is found in the majority of proteins and attack by the hydroxyl anion can be expected in the water environment. The studied competing reaction mechanisms encompass (i) nucleophilic substitution on sulphur with two different angles of attack, (ii) nucleophilic substitution on a-carbon, (iii) eliminatinon from β - or (iv) α -carbon and (v) internal elimination reaction without participation of OH^- nucleophile. The minimal energy pathways do not allow for unequivocal distiction of the preffered mechanism.