反应详情

A solution of NaOMe (0.143 M, 0.7 mL) was added to a suspension of 4i (See FIG. 7) (1 g, 2.2 mmol) in MeOH (10 mL) under N2. After 3 hours, the resulting solution was passed through a Dowex 50W(H+) plug (2×1 cm, eluant MeOH) and the solvent removed. The residue was purified by flash chromatography (MeOH:EtOAc, 2:25) to give 2-bromoethyl α-D-mannopyranoside 4d (See FIG. 7) (The use of 4d as a reactant has been described previously, although no details of preparation or characterization were given. (U.S. Pat. No. 4,918,009 to Nilsson, which is hereby incorporated by reference)) (606 mg, 96%) as a white foam; [α]26D=+50.7 (c 0.91, H2O); IR (KBr) 3417 cm−1 (OH); 1H NMR (500 MHz, D2O, COSY) δ 3.38-3.44 (m, 3H, H-4, —CH2Br), 3.50-3.55 (m, 2H, H-5, H-6), 3.60 (dd, J2,3 3.5 Hz, J3,4 9.7 Hz, 1H, H-3), 3.66 (dd, J5,6′ 4.6 Hz, J6,6′ 11.2 Hz, 1H, H-6′), 3.68 (ddd, J4.6 Hz, J5.4 Hz ,J 11.7 Hz, 1H, —OCHH′—), 3.76 (dd, J1,2 1.8 Hz, J2,3 3.5 Hz, 1H, H-2), 3.81 (ddd, J5.1 Hz, J6.5 Hz, J11.7, 1H, —OCHH′—), 4.71 (d, J1,2 1.8 Hz, 1H, H-1); 13C NMR (100 MHz, D2O) δ 32.1 (—CH,Br), 61.7 (—OCH2—), 67.5, 68.4, 70.7, 71.3, 73.8 (C-2, C-3, C-4, C-5, C-6), 100.5 (C-1); HRMS m/z (FAB+): Found 308.9985 (M+Na+); C8H15O6 79BrNa requires 308.9950. NaSSO2CH3 (150 mg, 1.12 mmol) was added to a solution of 4d (See FIG. 7) (245 mg, 0.85 mmol) in DMF (10 mL) under N2 and warmed to 50° C. After 16 hours, the solution was cooled and the solvent removed. The residue was purified by flash chromatography (MeOH:EtOAc, 1:9) to give 1d (See FIG. 7) (217 mg, 80%) as a hygroscopic foam; [α]29D=+58.0 (c 1.34, H2O); IR (KBr) 3441 cm−1 (OH), 1314, 1132 cm−1 (S—SO2); 1H NMR (500 MHz, D2O) δ 3.31 (t, J 5.8 Hz, 2H, —CH2S—), 3.35 (s, 3H, CH3SO2—), 3.45 (t, J9.6 Hz, 1H, H-4), 3.49 (ddd, J4,5 9.8 Hz, J5,6 5.8 Hz, J5,6′ 1.9 Hz, 1H, H-5), 3.55 (dd, J5,6 5.8 Hz, J6,6′ 12.1 Hz, 1H, H-6), 3.60 (dd, J2,3 3.4 Hz, J3,4 9.0 Hz, 1H, H-3), 3.66 (dt, Jd 10.7 Hz, Jt 5.7 Hz, 1H, —OCHH′—), 3.69 (dd, J5,6′ 1.9 Hz, J6,6′ 12.1 Hz, 1H, H-6′), 3.77 (dd, J1,2 1.6 Hz, J2,3 3.4 Hz, 1H, H-2), 3.83 (dt, Jd 11.0 Hz, Jt 5.9 Hz, 1H, —OCHH′—), 4.72 (d, J1,2 1.6 Hz, 1H, H-1); 13C NMR (125 MHz, D2O) δ 36.7 (—CH2S—), 50.7 (CH3SO2—), 61.9 (—OCH2—), 66.7, 67.7, 70.9, 71.5, 74.0 (C-2, C-3, C-4, C-5, C-6), 100.8 (C-1); HRMS m/z (FAB+): Found 319.0528 (M+H+); C9H19O8S2 requires 319.0521.

1. customthe solvent removed
2. customThe residue was purified by flash chromatography (MeOH:EtOAc, 2:25)