Hydrolysis of the Peptide Bond in N-Acetylated L-Methionylglycine Catalyzed by Various Palladium(II) Complexes: Dependence of the Hydrolytic Reactions on the Nature of the Chelate Ligand in cis-[Pd(L)(H2O)2]21 Complexes

Autor: Snežana Rajković, Darko P. Ašanin, Dora Molnar-Gabor, Milosš I. Djuran
Rok vydání: 2004
Předmět:
Zdroj: Monatshefte für Chemie/Chemical Monthly. 135:1445-1453
ISSN: 1434-4475
0026-9247
DOI: 10.1007/s00706-004-0232-4
Popis: Hydrolytic reactions between various palladium(II) complexes of the type cis-[Pd(L)(H2O)2]2+ in which L is ethylenediamine (en), 1,2-propylenediamine (1,2-pn), isobutylenediamine (ibn), 1,2-diaminocyclohexane (1,2-dach), N-methylethylenediamine (Meen), N,N,N′,N′-tetramethylethylenediamine (Me4en), S-methyl L-cysteine (MeS-L-HCys), L-methionine (L-HMet), and 2,5-dithiahexane (dth) and dipeptide N-acetylated L-methionylglycine (MeCOMet-Gly) were studied by 1H NMR spectroscopy. The reactions were carried out in the pH range 2.0–2.5 and at 50°C. In all these reactions, palladium(II) complex bound to a methionine residue effects the regioselective cleavage of the amide bond involving the carboxylic group of methionine. We found that the rate of hydrolysis and mechanism of this reaction are strongly dependent from the nature of the chelate ligand L in palladium(II) complexes of the type cis-[Pd(L)(H2O)2]2+.
Databáze: OpenAIRE