Reaction Steps
Compound 6a (0.28 g, 1.0 mmol) was added to a dry 3-neck flask containing NaH (60% dispersion in mineral oil, 0.12 g, 3.1 mmol) in DMF (10 mL) at 0° C. After 30 min at 0° C., sulfamoyl chloride (0.36 g, 3.1 mmol) was added in portions, and the reaction was stirred for an additional 1 hour at 0° C. The reaction mixture was quenched with H2O at 0° C. and diluted with ice cold H2O (20 mL) and dichloromethane (50 mL). The aqueous layer was removed, and the organic layer was washed with ice cold water (2×20 mL) and brine (1×20 mL). The organic layer was dried over Na2SO4, filtered, and concentrated in vacuo. Column chromatography (SiO2, a gradient of pure hexanes to a 2:3 ratio of ethyl acetate in hexanes) followed by preparative TLC (SiO2, 7:13 ratio of ethyl acetate in hexanes) on the crude mixture afforded a yellow glass (0.28 g, 0.80 mmol) 77% yield. 1H NMR (500 MHz, CDCl3): δ 4.98 (s, 2H), 4.75 (d, 1H, J=8.5 Hz), 4.15 (q, 2H, J=7.5 Hz), 3.99 (dd, 1H, J=8.0, 3.0 Hz), 3.88-3.82 (m, 2H), 3.69 (dd, 1H, J=11.0, 10.0 Hz), 3.22 (ddd, 1H, J=10.0, 10.0, 5.5 Hz), 2.18 (dd, 1H, J=5.0, 3.0 Hz), 1.96-1.94 (m, 1H), 1.50 (s, 3H), 1.40 (s, 3H) 1.27 (t, 3H, J=7.5 Hz) (FIG. 19). 13C NMR (500 MHz, CDCl3): δ 100.2, 77.9, 71.2, 63.3, 61.9, 61.3, 58.8, 31.0, 29.0, 22.6, 20.8, 19.2, 14.2 (FIG. 20). HRMS (m/z): [M+H]+ calculated for C13H22NO8S, 352.1061. found 352.1061. Anal. calculated for C13H21NO8S: C, 44.44; H, 6.02. Found C, 44.54; H, 5.80.
