Cesium carbonate → 2-(Octadecylthio)ethyl 2,3,6-tri-O-acetyl-4-O-{2,3,6-tri-O-acetyl-4-O-[2,3,4-tri-O-acetyl-6-O-(2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl)-alpha-D-glucopyranosyl]-alpha-D-glucopyranosyl}-beta-D-glucopyranoside

Participants

Reaction Steps

Compound 93 (265 mg, 0.2 mmol), octadecanethiol (86 mg, 0.3 mmol), cesium carbonate (79 mg, 0.24 mmol) and N,N-dimethylformamide (10 ml) were stirred at room temperature until 93 had been consumed (48 h; TLC, SiO2, ethyl acetate:isooctane 4:1). The solvent was removed and the residue was chromatographed (SiO2, ethyl acetate:isooctane 1:1) to give 96 (142 mg, 44%). [α]D25 +93° (c 0.5, chloroform). 1H-NMR (CDCl3, Me4Si) δ 5.30, 5.22, 5.12 (3d, each 1H, J=4.0, 4.2 and 3.7 Hz, H1', H1", H1"'), 4.51 (d, 1H, J=7.9 Hz, H1), 2.62, 2.46 (2t, each 2H, J=7.0 Hz, CH2 --S--CH2). 13C-NMR (CDCl3, Me4Si) δ 170.5-169.1 (CO), 100.2 (Cl), 95.7, 95.6, 95.2 (Cl', Cl", Cl"'), 75.1, 73.7, 72.6, 72.0, 71.6, 70.6, 70.3, 70.0, 69.8, 69.7, 69.6, 69.3, 69.2, 68.8, 68.4, 68.3, 67.3, 65.2, 63.0, 62.9, 61.7, 32.4, 31.8, 31.2, 29.6, 29.5, 29.5, 29.4, 29.2, 29.1, 28.7, 22.6, 20.8-20.5, 14.0.

Provenance & Evidence