2-furoyl-L-phenylalanyl-glycyl-glycine 、 (S)-2-amino-5-(1-piperidinyl)pentanoic acid N-[2-(1-piperidinyl)ethyl]amide 以(S)-2-[(2-furoyl)-β-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoic acid [2-(1-piperidinyl)ethyl]amide (20.8 mg) was obtained as a colorless oily material (yield 58%)的产率得到(S)-2-[(2-furoyl)-beta-cyclohexyl-L-alanyl-glycyl-glycyl-amino]-5-(1-piperidinyl)pentanoic acid [2-(1-piperidinyl)ethyl]amide