1973 Volume 26 Issue 11 Pages 625-646
Chymostatin, a chymotrypsin inhibitor, was shown to be a mixture of components A, B and C. The structure of component A as determined to be N-[((S)-1-carboxy-2-phenylethyl)-carbamoyl]-α-[2-iminohexahydro-4(S)-pyrimidyl]-L-glycyl-L-leucyl-phenylalaninal. Components B and C differed only in that the L-leucyl residue was replaced by L-valine and L-isoleucine, respectively.