tert-butyl (2S)-2-[({1-[(4'-fluorobiphenyl-2-yl)methyl]-2-oxo-1,2-dihydropyridin-3-yl}carbonyl)amino]-5-{[(2,2,5,7,8-pentamethyl-3,4-dihydro-2H-chromen-6-yl)sulfonyl]carbamimidamido}pentanoate 、
三氟乙酸 、
三乙基硅烷 以
水 为溶剂,
以to provide 180 mg (2S)-5-carbamimidamido-2-[({1-[(4′-fluorobiphenyl-2-yl)methyl]-2-oxo-1,2-dihydropyridin-3-yl}carbonyl)amino]pentanoic acid•TFA的产率得到(2S)-5-carbamimidamido-2-[({1-[(4'-fluorobiphenyl-2-yl)methyl]-2-oxo-1,2-dihydropyridin-3-yl}carbonyl)amino]pentanoic acid trifluoroacetate