反应详情

Compound 296 (85.0 mg, 148 mmol) was dissolved in dry THF (3 mL).). Tetrabutylammonium fluoride, 1.0M in THF (1.00 mL, 1.00 mmol) was added and the reaction stirred at room temperature for 2 hours. The solvent was removed in vacuo and silica gel chromatography (gradient elution hexanes+2.5%/0-100% ethyl acetate+2.5% TEA, then ethyl acetate+2.5% TEA/0-5% methanol) afforded a yellow solid. This residue was taken up in methanol (3 mL) and 1M ethanolic HCl (1 mL). Diethyl ether (20 mL) was added to precipitate the product, which was filtered and dried in vacuo to give compound 295 as a yellow solid (54 mg, 79%). 1H NMR (500 MHz, DMSO-d6) δ 10.75-10.97 (m, 2 H) 9.70 (s, 2 H) 9.47 (s, 1 H) 8.74 (d, J=3.67 Hz, 2 H) 8.16 (d, J=2.45 Hz, 1 H) 7.99-8.10 (m, 1 H) 7.84-7.99 (m, 1 H) 5.30-5.52 (m, 1 H) 3.81-3.96 (m, 4 H) 3.62-3.72 (m, 2 H) 3.20-3.36 (m, 6 H) 2.39-2.49 (m, 2 H) 2.02-2.20 (m, 4 H) 0.88 (d, J=6.85 Hz, 2 H) ppm.

1. customThe solvent was removed in vacuo and silica gel chromatography (
2. washgradient elution hexanes+2.5%/0-100% ethyl acetate+2.5% TEA
3. customethyl acetate+2.5% TEA/0-5% methanol) afforded a yellow solid
4. customto precipitate the product, which
5. filtrationwas filtered
6. customdried in vacuo