Uptake of molecular oxygen by Co(II) chelates with peptides in an aqueous colution : Part XI : Stereoselective properties of oxygenated diastereoisomeric dipeptide systems

The reaction of oxygen uptake by Co(II) complexes with a group of diastereoisimetric dipeptides, consisting of alanine and leucine in various chiral forms, has been studied in an aqueous solution. The structure of the bridging moiety has been discussed on the basis of spectroscopic results (UV, Vis, near IR, CD, ESR). The effect of stereoselectivity has been confirmed by studies of reversibility of oxygenation. Comparative ESR measurements were done for mixed complexes with imidazole as N-base in the axial position. All of the results were compared with that for glycine dipeptides (containing only one asymmetric atom).