反应详情

A mixture of N1-(benzo[d]isothiazol-3-yl)ethane-1,2-diamine (600 mg, 3.1 mmol), N α (t-butoxycarbonyl)phenylglycine (850 mg, 3.4 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (650 mg, 3.4 mmol), 1-hydroxybenzotriazole (520 mg, 3.4 mmol) and triethylamine (950 μL, 6.8 mmol) in dichloromethane (50 mL) was allowed to stir at room temperature overnight. The reaction mixture was washed successively with 1N aqueous hydrochloric acid, saturated sodium bicarbonate solution and water, then dried over anhydrous sodium sulfate, filtered and the filtrate concentrated under reduced pressure. Purification by flash column chromatography, on silica gel, eluting with a mixture of 30% ethyl acetate in hexanes and selected fractions were combined and concentrated under reduced pressure to give (S)-tert-butyl 2-(2-(benzo[d]isothiazol-3-ylamino)ethylamino)-2-oxo-1-phenylethylcarbamate (720 mg) as a white solid. 1H NMR (300 MHz, CDCl3): 7.78 (d, 1H), 7.61 (d, 1H), 7.49 (t, 1H), 7.30 (t, 1H), 7.21 (m, 2H), 7.18 (m, 2H), 6.95 (t, 1H), 5.66 (m, 2H), 5.10 (broad s, 1H), 3.62 (m, 4H), 1.39 ppm (s, 9H). MW=427 confirmed by LC-MS, tr=13.38 min (Method Y) MH+=428.

1. washThe reaction mixture was washed successively with 1N aqueous hydrochloric acid, saturated sodium bicarbonate solution and water
2. dry with materialdried over anhydrous sodium sulfate
3. filtrationfiltered
4. concentrationthe filtrate concentrated under reduced pressure
5. customPurification by flash column chromatography
6. washon silica gel, eluting with a mixture of 30% ethyl acetate in hexanes
7. concentrationconcentrated under reduced pressure