[CH3:1][C:2]1([CH3:14])[C:6]([CH3:8])([CH3:7])[O:5][B:4]([C:9]2[CH:10]=[N:11][NH:12][CH:13]=2)[O:3]1.S(OC)(O[CH2:19][C:20]1([CH2:24][O:25][CH2:26][C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)[CH2:23][O:22][CH2:21]1)(=O)=O.C(=O)([O-])[O-].[K+].[K+]>CN(C=O)C.CCOC(C)=O>[CH2:26]([O:25][CH2:24][C:20]1([CH2:19][N:12]2[CH:13]=[C:9]([B:4]3[O:5][C:6]([CH3:7])([CH3:8])[C:2]([CH3:14])([CH3:1])[O:3]3)[CH:10]=[N:11]2)[CH2:23][O:22][CH2:21]1)[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1A mixture of 4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (0.825 g, 4.25 mmol) and {3-[(benzyloxy)methyl]oxetan-3-yl}methyl methyl sulfate (Compound 44D, 1.35 g, 4.46 mmol) in DMF (3.90 mL) was charged with potassium carbonate (588 mg, 4.25 mmol) and allowed to stir at rt for 16 hrs. The reaction mixture was diluted with EtOAc and washed with brine (2×), dried over sodium sulfate, filtered and concentrated in vacuo and purified using a Teledyne ISCO Combiflash® Rf system [0→40% Acetone/Heptanes] to afford 1.37 g of the title compound (84%). 1H NMR (400 MHz, CD3OD) δ 7.76 (s, 1H), 7.66 (s, 1H), 7.25-7.37 (m, 5H), 4.67 (d, J=6.6 Hz, 2H), 4.48-4.52 (m, 4H), 4.42 (d, J=6.6 Hz, 2H), 3.45 (s, 2H), 1.20 (s, 12H). MS (ESI): m/z=385.20 [M+H]+. HPLC: tR=1.08 min (UPLC-TOF: polar—2 min).
Wird geladen…