Sodium Bicarbonate → HCID 87366546, compound

Participants

Reaction Steps

Trimethylsilyl trifluomethanesulfonate (35 μL, 0.19 mmol) was added dropwise to a stirred solution of the glycerol 39 (376 mg, 0.523 mmol) and O-(2,3,4,6-tetra-O-benzyl-α-D-galactopyranosyl)trichloroacetimidate (385 mg, 0.562 mmol) in dry ether (20 mL) under argon. After 90 min. solid NaHCO3 (100 mg) was added and the mixture stirred for a further 10 min. The reaction mixture was partitioned between ether (50 mL) and sat. NaHCO3 (40 mL). The aqueous phase was re-extracted with ether (50 mL) and the combined ethereal extract washed with 2M HCl (50 mL), sat. NaHCO3 (40 mL) and H2O (60 mL). After drying (MgSO4) and filtration the solvent was removed at reduced pressure to give the crude product that was purified by column chromatography on silica gel. Gradient elution with ethyl acetate/petroleum ether (10:90→20:80) afforded the title compound 41 (278 mg, 0.224 mmol, 61%) as a thin film; [α]D20 +64.2 (c 1.30, ethyl acetate); 1H NMR (300 MHz, CDCl3) δ 8.05-7.99 (m, 2H), 7.50-7.42 (m, 1H), 7.35-7.10 (m, 42H), 5.57-5.45 (m, 1H), 4.95-4.82 (m, 4H), 4.79-4.30 (m, 15H), 4.00-3.72 (m, 11H), 3.55-3.38 (m, 4H); 13C NMR (75 MHz, CDCl3) δ 166.3, 139.2, 139.1, 139.0, 138.5, 133.4, 130.6, 130.2, 128.7, 128.65, 128.6, 128.1, 127.8, 98.7 (1JCH 168 Hz), 98.3 (1JCH 168 Hz), 79.3, 79.2, 76.9, 75.6, 75.2, 73.8, 73.8, 73.5, 73.4, 72.9, 70.0, 69.3, 69.2, 67.3, 66.7; HRMS-ESI (+ve) (Found: m/z 1258.5888 (MNH4+). C70H84NO14 requires m/z 1258.886).

Provenance & Evidence