Copper(<scp>II</scp>) Co-ordination by oxime analogues of amino acids and peptides

Abstract

Complexes formed by the N-pyruvoylamino acid oximes CH3C(NOH)CONHCHRCO2H, where R = H, Me, CH2Ph or (CH2)2SMe, and 2-hydroxyiminopropanoic acid [alanine oxime, CH3C(NOH)-CO2H] and some derivatives with H+ and Cu2+ have been studied in aqueous solution using a combination of pH-metric titrations, UV/VIS and EPR spectroscopy. The oxime group was able to bind to Cu2+ through both the N and O donors from about pH 5 upwards with extensive formation of binuclear complexes, which dominated the equilibria in equimolar solutions.