反应详情

A solution of (R)-ethyl 3-amino-4-(5′-chloro-2′-fluorobiphenyl-4-yl)butanoate hydrochloride (293 mg, 0.777 mmol), succinic anhydride (93 mg, 0.932 mmol) and DIPEA (0.204 mL, 1.165 mmol) in dichloromethane (4 mL) is allowed to stir for 1.5 hours. The reaction is quenched with 1 M aqueous HCl and extracted with dichloromethane. The organic layer is separated and concentrated under reduced pressure. The resulting residue is purified by preparative HPLC using a gradient of 20% MeCN/water (0.1% TFA) to 100% MeCN to give (R)-4-(1-(5′-chloro-2′-fluorobiphenyl-4-yl)-4-ethoxy-4-oxobutan-2-ylamino)-4-oxobutanoic acid (294 mg). HPLC retention time=1.03 minutes (condition B); MS (m+1)=436.2; 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.28 (t, J=7.07 Hz, 3 H) 2.46-2.58 (m, 4 H) 2.64-2.68 (m, 2 H) 2.87 (A of ABX, Jab=13.64 Hz, Jax=7.83 Hz, 1 H) 2.99 (B of ABX, Jab=13.64 Hz, Jbx=6.57 Hz, 1 H) 4.11-4.22 (m, 2 H) 4.47-4.56 (m, 1 H) 6.60 (br d, J=8.59 Hz, 1 H) 7.05-7.10 (m, 1 H) 7.23-7.27 (m, 3 H) 7.39-7.41 (m, 1 H) 7.44-7.46 (m, 2 H).

1. customThe reaction is quenched with 1 M aqueous HCl
2. extractionextracted with dichloromethane
3. customThe organic layer is separated
4. concentrationconcentrated under reduced pressure
5. customThe resulting residue is purified by preparative HPLC