HCID 58292863, compound → 2-(3-Ethoxycarbonylmethyl-1-hydroxy-4-methyl-1,3-dihydro-benzo[c][1,2]oxaborol-6-yloxy)-thiazole-5-carboxylic acid
Reaction equation
C([O:5][C:6]([C:8]1[S:12][C:11]([O:13][C:14]2[CH:15]=[C:16]([CH3:30])[C:17]3[CH:21]([CH2:22][C:23]([O:25][CH2:26][CH3:27])=[O:24])[O:20][B:19]([OH:28])[C:18]=3[CH:29]=2)=[N:10][CH:9]=1)=[O:7])(C)(C)C>C(O)(C(F)(F)F)=O>[CH2:26]([O:25][C:23]([CH2:22][CH:21]1[O:20][B:19]([OH:28])[C:18]2[CH:29]=[C:14]([O:13][C:11]3[S:12][C:8]([C:6]([OH:7])=[O:5])=[CH:9][N:10]=3)[CH:15]=[C:16]([CH3:30])[C:17]1=2)=[O:24])[CH3:27]Participants
3
Procedure
2-(3-Ethoxycarbonylmethyl-1-hydroxy-4-methyl-1,3-dihydro-benzo[c][1,2]oxaborol-6-yloxy)-thiazole-5-carboxylic acid tert-butyl ester (3.3 g, 7.6 mmol) was treated with TFA (40 mL) and stirred at room temperature for overnight. The reaction mixture was concentrated and purified by column chromatography (silica, DCM/MeOH=20:1) affording the title compound (2.5 g, 87%) as a white foam. 1H NMR (CDCl3) δ 7.98 (s, 1H), 7.45 (d, 1H), 7.19 (d, 1H), 5.67 (dd, 1H), 4.20 (q, 2H), 3.12 (dd, 1H), 2.43 (m, 1H), 2.39 (s, 3H), 1.56 (s, 9H), 1.24 (t, 3H). MS found: (M+H)+: 378.05.