[CH2:1]([O:3][C:4]1[CH2:9][CH2:8][CH:7]([CH2:10][CH2:11][CH2:12][OH:13])[C:6](=[O:14])[CH:5]=1)[CH3:2].CCN(CC)CC.[CH3:22][N:23]1C(=O)O[C:26](=[O:27])[C:25]2=[CH:31][CH:32]=[CH:33][CH:34]=[C:24]12.O>CN(C1C=CN=CC=1)C.CN(C=O)C>[CH3:22][NH:23][C:24]1[CH:34]=[CH:33][CH:32]=[CH:31][C:25]=1[C:26]([O:13][CH2:12][CH2:11][CH2:10][CH:7]1[CH2:8][CH2:9][C:4]([O:3][CH2:1][CH3:2])=[CH:5][C:6]1=[O:14])=[O:27]Alcohol 3 (180 mg, 0.89 mmol), NEt3 (0.56 mL) and catalytic DMAP were added to a solution of N-methylisatoic anhydride (220 mg, 0.89 mmol) in dry DMF (2.0 mL) at rt. After stirring overnight, the solution was warmed to 65° C. for 3 h. After cooling to rt, water was added and this mixture was extracted with ethyl acetate (5×50 mL). The combined organic layers were washed with brine, dried over Na2SO4, filtered, and evaporated to give the crude product, which was purified by flash column chromatography to afford 87.0 mg (45% yield) of 4 as a white solid: 1H NMR (300 MHz, CDCl3) δ 7.85 (1H, m), 7.33 (1H, m), 6.56 (2H, m), 5.27 (1H, s), 4.22 (2H, t, J=5.2 Hz), 3.85 (2H, q, J=7.0 Hz), 2.86 (3H, s), 2.39 (2H, t, J=5.3 Hz), 2.04-1.41 (7H, m), 1.31 (3H, t, J=7.0 Hz); 13C NMR (75 MHz, CDCl3) δ 201.1, 176.8, 168.7, 151.7, 134.7, 131.7, 115.0, 111.3, 110.6, 102.5, 101.9, 64.7, 64.5, 64.3, 44.9, 30.0, 28.2, 26.6, 26.5, 26.4, 14.3; ESI MS m/z 354 (M++Na+).
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