(3S,2'S)-3-[N-((2'-(1-naphthyloxy)-4'-carboxy)butyryl)leucinyl]amino-4-oxobutanoic acid semicarbazone 以
四氢呋喃 、 aqueous formaldehyde(1.0 ML)-acetic acid(1.0 ML)-methanol 为溶剂,
以85%的产率得到(3S,2'S)-3-[N-((2'-(1-Naphthyloxy)-4'-Carboxy)Butyryl)Leucinyl]Amino-4-Oxobutanoic Acid