L-Norleucinamide,N-(3-methyl-1-oxobutyl)-L-phenylalanyl-N-[4-[[2-[[1-(2-carboxy-1-hydroxyethyl)-3-methylbutyl]amino]-1-methyl-2-oxoethyl]amino]-2-hydroxy-1-(2-methylpropyl)-4-oxobutyl]-,[1S-[1R*,2R*,4[R*[R*(R*)]]]]-; Pepstatin A, 1-[N-(3-methyl-1-oxobutyl)-L-phenylalanine]-2-L-norleucine-;SR 42128