反应详情

A solution of the title compound of Example 1, (2R)-(4-chlorobiphenyl-4-sulfonylamino)-5-(1,3-dioxo-1,3-dihydroisoindol-2-yl)pentanoic acid (20.0 mg, 0.039 mmol), in 2 mL of tetrahydrofuran is treated with 1M aqueous lithium hydroxide. After 2 h, the solution is acidified with 0.2 mL of 1N aqueous HCl, and the mixture is concentrated to an oil. Chomatography on LiChoprep DIOL (eluant; ethyl acetate) affords 12.8 mg (62%) of (4R)-N-[4-(4′-chlorobiphenyl-4-sulfonylamino)-4-carboxybutyl]phthalamic acid as a white solid: m.p. 119-121° C. (dec); IR 1737, 1701, 1649, 1344, 1168; ESI-MS 529 (M−−1).

1. concentrationthe mixture is concentrated to an oil