Sulfinimine-mediated asymmetric Strecker

Davis and Fanelli applied the sulfinimine mediated asymmetric Strecker synthesis to the enantioselective synthesis of the racemization-prone (/ )-(4-methoxy-3,5-dihydroxyphenyl)glycine (134) from 133.81 This amino acid is the central amino acid of the clinically important glycopeptide antibiotic vancomycin as well as related antibiotics. 

The sulfinimine-mediated asymmetric Strecker reaction was developed by F.A. Davis et al. This method involves the addition of ethylaluminumcyanoisopropoxide to functionalized sulfinimines and the resulting diastereomeric a-amino nitriles are easily separated. Subsequent hydrolysis directly affords the enantiopure a-amino acids. This protocol was applied for the synthesis of polyoxamic acid lactone. ... 

Davis, F. A., Prasad, K. R., Carroll, P. J. Asymmetric Synthesis of Polyhydroxy a-Amino Acids with the Sulfinimine-Mediated Asymmetric Strecker Reaction 2-Amino 2-Deoxy L-Xylono-1,5-lactone (Polyoxamic Acid Lactone). J. Org. Chem. 2002, 67, 7802-7806. 

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