Process for producing threo-3-amino-2- hydroxybutanoyl-aminoacetic acids, as well as novel intermediates therefor and process for producing them

Abstract From the Canadian patent

A process for producing threo-3-amino-2-hydroxybutanoylaminoacetic acids comprises the steps of allowing to react a starting compound represented by the general formula: (I), wherein R1 represents a naphthyl or a group of the formula: in which R6 and R7 represent individually hydrogen halogen, amino, or a protected amino, hydroxy or a protected hydroxy a lower, alkoxy, a lower alkyl or phenyl and R2 represents a protected amino, with a starting compound represented by the general formula:, (II), wherein R3 represents hydrogen or an ester residue to obtain, threo-3-protected amino-2-hydroxy-4-oxobutanoic acid or its ester represented by the general formula:, (III) wherein R1, R2 and R3 have …