Stereocontrolled conversion of some optically active (4S,5R)-dihydroisoxazoles into acyclic 3-acetamido-1,2-diols

Optically active (4S,5R)-dihydroisoxazoles (90–91% ee) have been prepared by reaction of the epoxyketones with hydroxylamine. Reduction of compounds using lithium aluminium hydride took place exclusively from the Re face to give (1R,2S,3S)-1,3-disubstituted-3-aminopropane-1,2-diols . These amino-diols were characterised by N-acetylation and the stereochemical sense of the hydride reduction was confirmed by conversion of amides into α-amino acid derivatives .