Ethyl isocyanate → 4-Amino-2-(3-ethylureido)-N-(1-hydroxy-1,3-dihydrobenzo[c][1, 2]oxaborol-6-yl)benzenesulfonamide

Participants

Reaction Steps

To a solution of 2,4-diamino-N-(1-hydroxy-1,3-dihydrobenzo[c][1,2]oxaborol-6-yl)benzenesulfonamide (1.0 g, 3.13 mmol) in DMF (15 ml) was added isocyanatoethane (0.5 g, 7.0 mmol) dropwise at room temperature. The reaction mixture was stirred at room temperature overnight, diluted with ethyl acetate and washed with H2O, brine. The organic fraction was then dried (MgSO4) and concentrated in vacuo. The residue was purified by Prep-HPLC to give the title compound as a white powder (0.3 g). 1H NMR (400 MHz, DMSO-d6) δ ppm 9.87 (s, 1H), 9.17 (s, 1H), 7.99 (s, 1H), 7.43 (d, J=1.6 Hz, 1H), 7.34 (d, J=2.0 Hz, 1H), 7.31 (d, J=8.4 Hz, 1H), 7.24 (d, J=8.0 Hz, 1H), 7.12 (dd, J=2.0, 8.4 Hz, 1H), 7.02 (t, J=5.2 Hz, 1H), 6.08 (dd, J=2.0, 8.4 Hz, 1H), 5.88 (s, 2H), 4.87 (s, 2H), 3.04˜3.11 (m, 2H), 1.07 (t, J=7.2 Hz, 3H); MS (ESI) m/z=389 (M−1, negative); HPLC purity: 93.6% (MaxPlot 200-400 nm), 90.3% (220 nm).

Provenance & Evidence