New asymmetric syntheses of β-hydroxy α-amino acids and analogues. Components of biologically active cyclopeptides

Abstract

MeBmt and analogues components of cyclosporine 2. were prepared by nucleophilic regioselective opening of chiral epoxyacids by methylamine. An efficient asymmetric hydrogenation-electrophilic emination sequence of β-ketoesters allowed the production of anti β-hydroxy-α-amino acids present in cyclopeptides (luzopeptine, vancomycin). An ideal kinetic dynamic resolution of α-acylamido-β-ketoester using ruthenium catalysts has been used for the production of L and D-threonine. This sequence was used for the preparation of (2S, 3R)-methyl-2-amino-3-(3′-chloro-4′-hydroxyphenyl) propionate precursor of a key component of vancomycin L.