Vancomycin-copper complex

Berthod et al. also tried copper complexation with teicoplanin and TAG CSPs [19]. Similar results were obtained. Amino acid enantiomers perfectly separated by both teicoplanin and TAG CSP could no longer be separated as soon as copper was present in the mobile phase. The copper-teicoplanin complex is also formed with the primary amine group on the peptidic teicoplanin basket (Figs. 1 and 3). However, unlike the vancomycin-copper complex which was very stable [18], the teicoplanin-copper complex was found to be reversible. Indeed, amino acid enan-tioselectivity was mostly restored after washing the chiral column with several column volumes of copper-free clean mobile phase [19]. 

Nair, U.B. et al.. Elucidation of vancomycin s enantioselective binding site using its copper complex. Chirality, 8, 590, 1996. 

Vancomycin is able to form a stable complex with copper [18]. This complex involves the secondary amine attached to the peptidic chain of the selector rigid basket and not the very mobile or accessible primary amine of a sugar unit (Fig. 1). Nair et al. established that all enantiorecognition capability of vancomycin disappeared upon copper complexation [18]. The authors concluded that the secondary... 

Fig. 6 Structure of the Cu-vancomycin complex. The dotted circle shows the copper 11 ion. Reprinted by permission of Wiley [6]...

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