p. 1158 - 1176
(2007/10/03)di-tert-butyl dicarbonate
(S)-3-[3-(1-benzyloxycarbonyl-4-benzyloxycarbonylaminobutyl)ureido]benzoic acid ethyl ester
ethyl 3-isocyanatobenzoate
(S)-2-amino-5-benzyloxycarbonylamino-pentanoic acid benzyl ester hydrochloride