Ammonia → [(S)-2-(7-Carbamoyl-furo[2,3-g]indazol-1-yl)-1-methylethyl]-carbamic acid benzyl ester

Participants

Reaction Steps

To a stirred solution of the product from Step A (0.17 g, 0.43 mmol) in DMF (5 mL) was added 1-hydroxy-benzotriazole hydrate (0.029 g, 0.21 mmol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.13 g, 0.65 mmol) followed by a solution of ammonia in dioxane (0.5 M, 1.72 mL, 0.86 mmol). After 18 h, a saturated aqueous solution of ammonium chloride (20 mL) added and the mixture was extracted with ethyl acetate (3×50 mL). The combined extracts were washed with brine, dried and evaporated. The residue was purified by chromatography (silica, dichloromethane, 5% methanol in dichloromethane) to give an oil (0.14 g, 83%): MS (ES) m/z 393 (M+); 1H NMR (CDCl3) δ 8.20 (brs, 1H), 8.04 (s, 1H), 8.01 (s, 1H), 7.69 (d, 1H, J=8.0 Hz), 7.32-7.23 (m, 6H), 6.76 (brs, 2H), 5.03 (m, 2H), 4.63 (m, 2H), 4.40 (m, 1H), 1.16 (d, 3H, J=8.0 Hz).

Provenance & Evidence