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[摘要]:An efficient asymmetric synthesis of anti-1,12-disubstituted taurine derivatives through nucleophilic addition of phenyl-methanesulfonate to various N-acylimines in the presence of 1,2:5,6-di-O-isopropylidene-alpha-D-allofuranose as a chiral auxiliary is described. The taurine derivatives were obtained in three steps with good overall yields (36-61%) and excellent enantiomeric excesses (83-98%). The diastereomeric excesses of 15-91% could be improved to 90-98% by column chromatography or recrystallization. The relative and absolute configurations of the products were determined by means of an X-ray crystal structure analysis. |
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