S-benzyl-N-(S-benzyl-N-benzyloxycarbonyl-L-cysteinyl)-L-cysteine ethyl ester
S-benzyl-N-(N,N-phthaloyl-glycyl)-L-cystein-ethyl ester
S-benzyl-N-(N-benzyloxycarbonyl-L-valyl)-L-cysteine ethyl ester
S-benzyl-N-(N2-benzyloxycarbonyl-L-glutaminyl)-L-cysteine ethyl ester
N-(Benzyloxycarbonyl-glycyl)-S-benzyl-L-cystein-ethylester