反应详情

To a solution of phenyl 6-deoxy-2,3,4-tri-O-acetyl-1-thio-β-L-galactopyranoside 2 (0.892 g, 2.33 mmol) in 25 mL of methanol is added K2CO3 (0.644 g, 4.66 mmol). The reaction mixture is stirred at room temperature for 12 h. Amberlite resin (H+ form) is added to the reaction mixture and stirred for an additional 30 min. The neutralized mixture is then filtered through Celite, which is washed several times with methanol, and the filtrate is concentrated to afford 1.39 g of phenyl 6-deoxy-1-thio-β-L-galactopyranoside 3 as a yellow oil, which is used in the next step without further purification. The thioglycoside 3 can be purified using flash chromatography (10% MeOH/CH2Cl2): Rf 0.28 (10% MeOH/CH2Cl2); 1H NMR (C6D6, 270 MHz) δ 7.54-7.58 (m, 2H) 7.28-7.37 (m, 3H), 4.50 (d, J=8.2 Hz, 1H, H-1), 3.70 (q, J=6.6 Hz, 1H, H-5), 3.56-3.75 (m, 3H), 1.38 (d, J=6.6 Hz, 3H).

1. additionAmberlite resin (H+ form) is added to the reaction mixture
2. stirringstirred for an additional 30 min
3. filtrationThe neutralized mixture is then filtered through Celite, which
4. washis washed several times with methanol
5. concentrationthe filtrate is concentrated