tert-butyl (2S)-2-{[(1-benzyl-2-oxo-1,2-dihydropyridin-4-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 65 mg (2S)-2-{[(1-benzyl-2-oxo-1,2-dihydropyridin-4-yl)carbonyl]amino}-5-carbamimidamidopentanoic acid•TFA的产率得到(2S)-2-{[(1-benzyl-2-oxo-1,2-dihydropyridin-4-yl)carbonyl]amino}-5-carbamimidamidopentanoic acid trifluoroacetate