1H, 13C, 195Pt NMR study on platinum(II) interaction with sulphur containing Amadori compounds

AbstractThe NMR study on the interaction of Pt(II) with Amadori compounds is performed. The Amadori compounds are derived from the reaction of β-d-glucose with l-cystine leading to N,N′-di-(1-deoxy-β-fructos-1-yl)-l-cystine [FruCyscys], and with l-methionine leading to N-(1-deoxy-β-fructos-1-yl)-l-methionine [FruMet].The great instability of 2-(1,2,3,4,5-pentahydroxypentyl)-1,3-thiazolidine-4-carboxylic acid [GlcCys], formed by the condensation reaction of β-d-glucose and l-cysteine, prevents the formation of its Pt(II) complexes. Differently, FruMet well reacts with K2PtCl4 in 1:1 M/L molar ratio leading to the formation of [Pt(FruMet-N,S)Cl2], in which the Amadori compound coordinates the metal ion through nitrogen and sulphur atoms. FruMet originates also a solid trans complex [Pt(FruMet-N,S)2]Cl2. Its NMR solution study allowed to identify two isomers with respect to nitrogen and sulphur atoms: R,R and S,S.In [Pt2FruCyscysCl4] species, FruCyscys molecule links two Pt(II) ions giving rise to two pentaatomic N,S-chelate rings.