Oxygen → HCID 22841876, compound

Participants

Reaction Steps

A solution of 10 (500 mg)-in 20 mL of water was vigorously stirred with freshly prepared platinum black (200 mg) at 85 C. while oxygen was slowly passed through the suspension. The pH of the reaction was maintained at approximately 8.0 with solid sodium bicarbonate. It took about 2 hours to complete the oxidation. The mixture was cooled after an additional 10 minutes of stirring. After removal of the catalyst by passing the solution through a Nylon-66 0.45 μm pore size filter, the filtrate was lyophilized. The residue was redissolved in 20 mL of ice-water and the solution was adjusted to pH 2 with 12N HCl and extracted with chloroform. The extract was washed with water until neutral, dried over sodium sulfate and concentrated, and the residue was esterfied with ethereal diazomethane. The product was eluted from a column of silica gel (Rf 0.45, hexane-ethyl acetate, 75:25) to give amorphous methyl 1-O-(11-methoxycarbonylundecyl)-3-O-benzyl-2,4-di-O-acetyl-β-D-glucopyranosuronate (11).1H-NMR data: 7.26-7.30 (m, 5 H, arom.), 5.20 (t, 1 H), 5.08 (t,1 H), 4.62(s, 2 H, CH2Bn), 4.45(d, 1 H, anom.), 3.85-3.97 (m, 2 H) 3.73 (s,3 H, COOMe), 3.68(s, 3 H, COOMe), 2.36(t, 2 H, CH2 lipid), 1.98(s, 6 H, 2Ac), 1.20-1.63 (18 H, lipid).

Provenance & Evidence