Pyridine (0.28 ml) was added to a stirred solution of 6-chloro-5-methyl-2,3-dihydro-1H-indole (WO-9501976) (0.116 g) and 3-(4-trichloroacetylpiperazin-1-yl)-4-methoxybenzenesulfonyl chloride (D4) (300 mg) in dichioromethane (4 ml) at room temperature. After 18 h the solution was washed with 1M hydrochloric acid (5 ml), water (5 ml), dried (MgSO4) and concentrated to an oil. The oil was dissolved in 1,4-dioxan (13 ml) and a 0.15 M potassium hydroxide solution (6.5 ml) was added. The solution was stirred at room temperature for 4 h then concentrated to remove the organic solvent, diluted with water (10 ml) and the solution extracted with dichloromethane (20 ml). The organic phase was dried (Na2SO4), acidified with 1M ethereal hydrogen chloride (2 ml), concentrated to a solid and stirred with acetone to afford the title compound (0.175 g, 55%). MH+ 422/424.
