posted on 2021-02-08, 08:29authored byGiorgio Facchetti, Raffaella Bucci, Marco Fusè, Emanuela Erba, Raffaella Gandolfi, Sara Pellegrino, Isabella Rimoldi
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 and characterized.
The presence of an iridium(III) ligand at the N-terminus
of DADA allowed the use of the metalloenzyme as a catalyst in the
asymmetric transfer hydrogenation of cyclic imines. In particular,
the type of link between DADA and the metal-chelating moiety was found
to be fundamental for inducing asymmetry in the reaction outcome,
as highlighted by both computational studies and catalytic results.
Using the [IrCp*(m-I)Cl]Cl ⊂
Van complex in 0.1 M CH3COONa buffer at pH 5, a significant
70% (S) e.e. was obtained in the reduction of quinaldine B.