Metal Complexes of Pharmacophore-Containing Pectin with d-Elements Ions (Cu2+, Co2+, and Mn2+)

Spectral methods have been used to study the complexation of apple pectin modified with organic pharmacophores (nicotinic, salicylic, 5-aminosalicylic, or anthranilic acid) with Cu 2+ , Co 2+ , and Mn 2+ ions in an aqueous solution. The composition and stability series of the metal complexes, corresponding to the empirical Irving–Williams series, have been established. The standard thermodynamic parameters (Δ H °, Δ G °, and Δ S °) of the complexation process have been calculated. It has been shown by means of 13 C NMR and IR spectroscopy that the interaction of pharmacophore-containing pectins with d -metal ions (Cu 2+ , Co 2+ , Mn 2+ ) occurs via the carbonyl and hydroxyl groups of the modified polymer matrices. The viscosity and thermal properties of the metal complexes have been determined.