The title compound was synthesized according to the procedure of Example 41, Step 4 using the product of Step 3 (1 g, 2.6 mmol) and Oxone®(4 g, 6.6 mmol) in methanol (20 ml), tetrahydrofuran (10 ml) and water (5 ml). The crude product was purified by chromatography on silica gel using 50% ethyl acetate in toluene as the eluent to give 610 mg (75%) of the desired product as a crystalline solid: mp 265-267° C. Anal. Calc'd. for C19H17N2F3O3S (MW 410.41): C, 55.60; H, 4.18; N, 6.83; S, 7.81. Found: C, 55.69; H, 4.28; N. 6.70; S, 8.07.
