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The structure of dipepide AcMet-Gly was determined by X-ray crystallographic analysis. It possesses mono-clinic, space group P21 (No. 4), with cell dimensions of a=0.8571(2) nm, b=0.5871(2) nm, c=1.197(3) nm, =99.290(10), V=0.5944(15) nm3, Z=2, m=2.74 cm-1. Mononuclear chelates, described as [Pd(X)(S,N,O- AcMet-Gly)]+, in which Pd(II) is coordinated by thioether, deprotonated amide nitrogen, carbonyl oxygen of me-thionine and X (AcMetGly or other ligands present in aqueous solution or in mobile phase solution), were detected 5 min after mixing AcMet-Gly with [Pd(H2O)4]2+ at room temperature using electrospray ionization mass spectrometry. The geometry of [Pd(H2O)(S,N,O-AcMet-Gly)]+ is optimized at density functional B3LYP/LanL2DZ level. The fused five- and six-membered chelate is responsible for cleavage of Met-Gly bond. This is the first time to provide a direct evidence for Pd(II)-mediated cleavage of dipeptides via external solvent attack.
The structure of dipepide AcMet-Gly was determined by X-ray crystallographic analysis. It possesses mono-clinic, space group P21 (No. 4) with cell dimensions of a = 0.8571 (2) nm, b = 0.5871 , C = 1.197 (3) nm, = 99.290 (10), V = 0.5944 (15) nm3, Z = 2 and m = 2.74 cm- 1. Mononuclear chelates, described as [Pd - AcMet-Gly)] +, wherein which Pd (II) is coordinated by thioether, deprotonated amide nitrogen, carbonyl oxygen of me-thionine and X (AcMetGly or other ligands present in aqueous solution or in mobile phase solution), were detected 5 min after mixing AcMet-Gly with [Pd (H2O) 4] 2+ at room temperature using electrospray ionization mass spectrometry. The geometry of [Pd (H2O) (S, N, O-AcMet-Gly)] + is optimized at density functional B3LYP / LanL2DZ level. The fused five- and six-membered chelate is responsible for cleavage of Met-Gly bond. This is the first time to provide a direct evidence for Pd (II) -mediated cleavage of dipeptides via external solvent attack.