Reaction Steps
To a solution of (3R,3aS,6aR)-Hexahydrofuro[2,3-b]furan-3-yl (1S,2R)-3-[(1,3-benzodioxol-5-ylsulfonyl)(isobutyl)amino]-2-hydroxy-1-[4-(2-hydroxyethoxy)benzyl]propylcarbamate (0.11 g, 0.18 mmol), triethyl amine (0.055 mL, 40 mg, 0.39 mmol), and 4-dimethylaminopyridine (2 mg), in dichloromethane at 0° C. was added p-toluenesulfonyl chloride (38 mg, 0.2 mmol) and the mixture was stirred at ambient temperature for 4 h. Solvent was evaporated and the residue was purified by chromatography (silica gel, dichloromethane/methanol, 98:2) to provide the title compound as a solid foam (0.105 g). 1H NMR (DMSO-d6): δ 0.78 (3H, d), 0.82 (3H, d), 1.2 (1H, dd), 1.37 (1H, quintuplet), 1.9-2.0 (1H, m), 2.3 (1H, dd), 2.38 (3H, s), 2.6-2.8 (2H, m), 2.9 (1H, d), 2.97 (1H, dd), 3.2-3.3 (1H, m), 3.4-3.5 (1H, m), 3.5-3.6 (4H, m), 3.7 (1H, t), 3.8 (1H, dd), 4.0 (2H, d), 4.3 (2H, t), 4.8 (1H, dt), 5.0 (1H, d), 5.5 (1H, d), 6.18 (2H, s), 6.7 (2H, d), 7.0-7.1 (3H, m), 7.2 (1H, d), 7.22 (1H, s), 7.29 (1H, d), 7.4 (2H, d), 7.8 (2H, d); MS: 791 (MH+)
