N-[1-(2'-[N-tert-butoxycarbonyl-L-tyrosyl]amino-1'(R)-hydroxy)butylcarboxy]-L-phenylalanyl-L-leucyl methyl ester
N-[1-(2'-amino-1'R-hydroxy)butylcarboxy]-L-phenylalanyl-L-leucyl methyl ester
N-[1-(2'-azido-1'R-hydroxy)butylcarboxy]-L-phenylalanyl-L-leucyl methyl ester
N-[1-(2'-azido-1'R-hydroxy)butylcarboxy]-L-phenylalanyl-L-leucine
(R)-(+)-5-Hydroxy-2-oxopiperidine