4-(3-(4-methoxyphenyl)-1H-indol-2-yl)-3,5-dimethylisoxazole (the intermediate product of step (d) from Example 1, 35 mg, 0.11 mmol) was added to a suspension of NaH (25 mg, 60% in heptane) in DMF (dry, 0.7 ml) at 0° C. under nitrogen. The mixture was stirred at rt for 30 min and was then cooled to 0° C. again. Dimethylsulfamoyl chloride (2 eq) was added drop wise. The mixture was stirred at rt for 2 h, cooled to 0° C. and water was added to quench the reaction. Extraction with DCM using isolute phase separator and concentration of the combined organic layers afforded 2-(3,5-dimethylisoxazol-4-yl)-3-(4-methoxyphenyl)-N,N-dimethyl-1H-indole-1-sulfonamide in quantitative yield.
