Kinetic Studies and Mechanism of Hydrogen Peroxide Catalytic Decomposition by Cu(II) Complexes with Polyelectrolytes Derived from L-Alanine and Glycylglycine.

The catalytic decomposition of hydrogen peroxide by Cu(II) complexes with polymers bearing L-alanine (PAla) and glycylglycine (PGlygly) in their side chain was studied in alkaline aqueous media. The reactions were of pseudo-first order with respect to [H(2)O(2)] and [L-Cu(II)] (L stands for PAla or PGlygly) and the reaction rate was increased with pH increase. The energies of activation for the reactions were determined at pH 8.

Spectroscopic studies on the anticancer antibiotic Altromycin H and the interaction with copper(II) ions.

The antitumor antibiotic Altromycin H was studied using electronic absorption (UV-Vis.) and circular dichroism (CD) spectroscopy. The dissociation constants of the phenolic groups on C(5) and C(11) were estimated as pK(1)=6.

Studies on the interaction of altromycin B and its platinum(II) and palladium(II) metal complexes with calf thymus DNA and nucleotides.

The interaction of the anticancer antibiotic altromycin B and its isostructrural Pt(II) and Pd(II) metal complexes with native calf thymus (CT) DNA was studied using UV-thermal denaturation experiments, circular dichroism spectroscopy and temperature controlled spectrophotometric titrations. Altromycin B stabilizes the double helix by raising the T(m), mainly by intercalation of its chromophore between the base pairs and interacting electrostatically via its sugar moieties with the edges of the DNA helix. Moreover, altromycin B induces a B-->A structural transition of CT DNA.

Interactions of the anticancer antibiotic altromycin B with copper(II), palladium(II) and platinum(II) ions and in vitro activity of the formed complexes.

Interaction of the anticancer antibiotic altromycin B with Cu(II), Pd(II) and Pt(II) ions was studied using 1H-NMR, EPR, electronic absorption and circular dichroism spectroscopy. The results derived from NMR studies where that the Pt(II) and Pd(II) ions interact with the nitrogen atom of the dimethylamino group of the C(10)-disaccharide, while the C(2)-epoxide group does not participate and remains intact. Cu(II) ions interact in a different way with altromycin B as was concluded by EPR and circular dichroism spectra.