(S)-2-hydroxy-3-nitropropionic acid

(S)-2-oxazolidinone-5-carboxylic acid benzyl ester

(2S)-3-{[(benzyloxy)carbonyl]amino}-2-hydroxypropanoic acid

O-[3-amino-(2S)-t-butyldimethylsilyloxypropanoyl]-(1'R,2'S,5'R)-8'phenylmenthol

(+)-ethyl N,O-diacetyl-3-amino-2-hydroxypropionate