Heteroleptic platinum(IV) complexes with glycine and alanine

The formation of a heteroleptic complex of composition Pt(IV):Gly (C 2H5O2N):Ala (C3H7O 2N) = 1:1:1 (logβ = 11.90) in aqueous solution was studied by pH titration. The platinum(IV) complexes Pt(Gly-)(Ala -)Cl2·H2O and Pt(Gly-)(Gly) (Ala-)(Ala)Cl2·2H2O were synthesized and characterized by chemical, crystal-optical, thermogravimetric, X-ray diffraction, and IR-spectroscopic analyses. The amino acid ligands are coordinated to the platinum(IV) atom

Mixed-ligand platinum(IV) complexes with amino acids and adenine

Complexing in platinum(IV)-adenine-amino acid (α-alanine (Ala), lysine (Lys), or histidine (His)) systems was studied by pH titration. The stability constants of 1: 1: 1 complexes were determined. The stability of these mixed-ligand complexes changes in the following order: Lys < Ala < His. Reactions between aqueous solutions of H2PtCl6 and amino acids produced the following coordination compounds: Pt(C3H 6NO2)(C5H5N5)Cl 3 • 2H2O, or Pt(Ala-)(Ade)Cl3 • 2H2O (I); Pt(C5H5N5)(C 6H14N2O2)Cl4 • 2H2O, or Pt(Ade)(Lys)Cl4 • 2H2O (II); and Pt(C5H5N5)(C6H9N 3O2)Cl4 • 3H2O or Pt(Ade)(Hist)Cl4 • 3H2O (III). These complexes were characterized by 13C NMR, IR, and X-ray photoelectron spectroscopy. Alanine is complexed via both amino and carboxy groups; lysine, via α-amino group exclusively; and histidine, via the amino group and the N3 heterocyclic atom. Adenine in these complexes is monodentate due to the N7 heterocyclic atom. The adenine amino group is apparently H-bonded to a water oxygen atom. © 2008 Pleiades Publishing, Ltd

Mixed-ligand platinum(IV) complexes with amino acids and adenine

Complexing in platinum(IV)-adenine-amino acid (α-alanine (Ala), lysine (Lys), or histidine (His)) systems was studied by pH titration. The stability constants of 1: 1: 1 complexes were determined. The stability of these mixed-ligand complexes changes in the following order: Lys < Ala < His. Reactions between aqueous solutions of H2PtCl6 and amino acids produced the following coordination compounds: Pt(C3H 6NO2)(C5H5N5)Cl 3 • 2H2O, or Pt(Ala-)(Ade)Cl3 • 2H2O (I); Pt(C5H5N5)(C 6H14N2O2)Cl4 • 2H2O, or Pt(Ade)(Lys)Cl4 • 2H2O (II); and Pt(C5H5N5)(C6H9N 3O2)Cl4 • 3H2O or Pt(Ade)(Hist)Cl4 • 3H2O (III). These complexes were characterized by 13C NMR, IR, and X-ray photoelectron spectroscopy. Alanine is complexed via both amino and carboxy groups; lysine, via α-amino group exclusively; and histidine, via the amino group and the N3 heterocyclic atom. Adenine in these complexes is monodentate due to the N7 heterocyclic atom. The adenine amino group is apparently H-bonded to a water oxygen atom. © 2008 Pleiades Publishing, Ltd

Heteroleptic platinum(IV) complexes with glycine and alanine

The formation of a heteroleptic complex of composition Pt(IV):Gly (C 2H5O2N):Ala (C3H7O 2N) = 1:1:1 (logβ = 11.90) in aqueous solution was studied by pH titration. The platinum(IV) complexes Pt(Gly-)(Ala -)Cl2·H2O and Pt(Gly-)(Gly) (Ala-)(Ala)Cl2·2H2O were synthesized and characterized by chemical, crystal-optical, thermogravimetric, X-ray diffraction, and IR-spectroscopic analyses. The amino acid ligands are coordinated to the platinum(IV) atom

Mixed-ligand platinum(IV) complexes with amino acids and cytosine

Complex formation in platinum(IV)-cytosine-amino acid (glycine, α-alanine, lysine, or histidine) systems is studied using pH titration. Stability constants for 1:1:1 stoichiometry of complexes are determined. The stability of the mixed-ligand complexes varies in the following order: Lys < Ala < Gly < His. Reactions of aqueous solutions yields the following complexes: Pt(Cyt)(Gly-)Cl3 • 3H2O (I), pt(Cyt)(Ala-)Cl3 • 3H2O (II), Pt(Cyt)(Hist)Cl4 • 2H2O (III), and Pt(Cyt)(Lys)Cl4 • 2H2O (IV). 13C NMR, IR, and XPS spectra show that glycine and alanine are complexed via amino and carboxy groups, lysine via its α-amino group exclusively, and histidine via its amino group and heterocyclic N3 atom. Cytosine in these complexes is bidentate (it is complexed via C=O oxygen and N3 heterocyclic atoms). © 2008 Pleiades Publishing, Ltd

Mixed-ligand platinum(IV) complexes with amino acids and cytosine

Complex formation in platinum(IV)-cytosine-amino acid (glycine, α-alanine, lysine, or histidine) systems is studied using pH titration. Stability constants for 1:1:1 stoichiometry of complexes are determined. The stability of the mixed-ligand complexes varies in the following order: Lys < Ala < Gly < His. Reactions of aqueous solutions yields the following complexes: Pt(Cyt)(Gly-)Cl3 • 3H2O (I), pt(Cyt)(Ala-)Cl3 • 3H2O (II), Pt(Cyt)(Hist)Cl4 • 2H2O (III), and Pt(Cyt)(Lys)Cl4 • 2H2O (IV). 13C NMR, IR, and XPS spectra show that glycine and alanine are complexed via amino and carboxy groups, lysine via its α-amino group exclusively, and histidine via its amino group and heterocyclic N3 atom. Cytosine in these complexes is bidentate (it is complexed via C=O oxygen and N3 heterocyclic atoms). © 2008 Pleiades Publishing, Ltd