CATALYTIC ASYMMETRIC SYNTHESIS OF ESOMEPRAZOLE BY A TITANIUM COMPLEX WITH A HEXA-AZA-TRIPHENOLIC MACROCYCLE LIGAND

An efficient synthesis of esomeprazole via catalytic asymmetric oxidation of 1H-benzimidazolyl pyridinylmethyl sulfide by a titanium complex with a hexa-aza-triphenolic macrocycle ligand is described. Esomeprazole was prepared with 99.6% ee, which meets the high requirement of the European Pharmacopeia on enantiomeric purity.