COPPER(II) COORDINATION BY OXIME ANALOGS OF AMINO-ACIDS AND PEPTIDES

Complexes formed by the N-pyruvoylamino acid oximes CH3C(=NOH)CONHCHRC O(2)H, where R = H, Me, CH(2)Ph or (CH2)(2)SMe, and 2-hydroxyiminoprop anoic 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 domi nated the equilibria in equimolar solutions.