Efficientasymmetricsynthesis of chiral glycerol derivatives was realized by lipase-catalyzed reaction in organic medium and its application for synthesis of (S)-propranolol was demonstrated.
An enzymatic synthesis of 2, 3-O-isopropylidene-sn-glycerol (10), the synthetic key intermediate for platelet-activating factor, was achieved. Several 1, 3-di-O-acyl-2-benzylglycerols (5a-d) were synthesized from dihydroxyacetone dimer (2), and subjected to enzyme-catalyzed asymmetric hydrolysis. The optical purities of the mono-hydrolyzed products (6) were determined from the 400 MHz proton nuclear magnetic resonance spectra after conversion of 6 to the esters of (-)α-methoxy-α-trifluoromethylphenylacetic acid. Upon hydrogenolysis of the benzyl ether, followed by protection of diol and hydrolysis of the acetate, (-)-6a afforded 10.
Desymmetrization of Glycerol Derivatives with Peptide-Based Acylation Catalysts
作者:Chad A. Lewis、Bianca R. Sculimbrene、Yingju Xu、Scott J. Miller
DOI:10.1021/ol051061a
日期:2005.7.1
Nucleophile-loaded peptides have been evaluated as catalysts for the desymmetrization of glycerol derivatives through an enantioselective acylation process. Enantiomeric excesses of up to 97% have been obtained for the monoacylated products. A range of other substrates have been examined that shed light on the mechanistic basis of the desymmetrizations.