2-(Hexadecylsulfonyl)ethyl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranoside. 2-Bromoethyl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranoside (Dahmen et al. Carbohydr. Res., 116 (1983)) (540 mg, 1.19 mmol), hexadecanethiol (383 mg, 1.49 mmol), cesium carbonate (292 mg, 0.89 mmol) and dimethylformamide (5 ml) was stirred overnight. Dichloromethane (75 ml) and water (40 ml) were added. The aqueous phase was extracted with dichloromethane (2×25 ml), the combined organic phases were dried (Na2SO4) and concentrated. Chromatography (SiO2 ; ethylacetate: hexane) gave pure 2-(hexadecylthio)ethyl 2,3,4,6-tetra-O-acetyl-β-D-glucopyranoside (480 mg, 0.76 mmol, 64%), which was dissolved in ethyl acetate (12 ml) and treated with m-chloroperbenzoic acid (1.71 mmol). After 4 hours the solvents were removed and the residue was dissolved in dichloromethane and filtered through alumina (10 g) to give the pure sulfone lipid (495 mg, 98%). [α]D23 =-8.7° (c=0.9 in CDCl3).
