The synthesis of (S)-(+)-pantolactone and its analogues from an ephedrine-derived morpholinone
作者:Bidhan A. Shinkre、Abdul Rakeeb A.S. Deshmukh
DOI:10.1016/j.tetasy.2004.02.022
日期:2004.4
An efficient general route for the enantioselective synthesis of (S)-(+)-pantolactone and its analogues has been developed from an ephedrine-derived chiral morpholin-3-one. Selective dialkylation of an ephedrine-derived chiral template without epimerization is the key step in this synthesis. (C) 2004 Elsevier Ltd. All rights reserved.
Enantioselective Synthesis of (<i>S</i>)-(+)-Pantolactone
作者:Sunil V. Pansare、Rajendra P. Jain
DOI:10.1021/ol990372g
日期:2000.1.1
alkylidene morpholinone derived from (1R,2S)-ephedrine and 3-methyl-2-oxobutanoic acid proceeds with good diastereoselectivity to generate a spiro bis-acetal. Lewis acid mediated diastereoselective reductive cleavage of the spiro acetal and subsequent removal of the ephedrine portion generates a alpha-hydroxy-gamma-methoxy carboxamide which is readily converted to (S)-(+)-pantolactone with high enantiomeric