Under argon, 200 mg (0.71 mmol) of 5-nitro-N-phenyl-1H-indole-2-carboxamide from Example XLVIII are initially charged in 5 ml of dimethylformamide. 85.3 mg (2.13 mmol) of sodium hydroxide (60% dispersion in paraffin) are added a little at a time, and the mixture is stirred at RT for 30 min. 657 mg (3.56 mmol) of (2-bromoethyl)benzene are then added, and the mixture is stirred at 100° C. for another 5 h. To terminate the reaction, a further 3 eq. of sodium hydride and 5 eq. of bromide are added, and the mixture is stirred at 100° C. for 7 hours. The reaction mixture is poured into aqueous hydrochloric acid and extracted with ethyl acetate. The organic phase is dried over sodium sulphate and the solvent is removed using a rotary evaporator. The resulting crude product is purified by column chromatography (silica gel 60, mobile phase: cyclohexane/ethyl acetate 6:1).
