Alternative Strategy to Obtain Artificial Imine Reductase by Exploiting Vancomycin/D-Ala-D-Ala Interactions with an Iridium Metal Complex

Based on the supramolecular interaction between vancomycin (Van), an antibiotic glycopeptide, and D-Ala-D-Ala (DADA) dipeptides, a novel class of artificial metalloenzymes was synthesized characterized. The presence iridium(III) ligand at N-terminus DADA allowed use metalloenzyme as catalyst in asymmetric transfer hydrogenation cyclic imines. In particular, type link metal-chelating moiety found to be fundamental for inducing asymmetry reaction outcome, highlighted by both computational studies catalytic results. Using [IrCp*(m-I)Cl]Cl ⊂ Van complex 0.1 M CH3COONa buffer pH 5, significant 70% (S) e.e. obtained reduction quinaldine B.