To a solution of 242 mg of 1-(2-chloropyridin-4-ylmethyl)-3-[1-(2-dimethylamino-acetyl)-3,3-dimethyl-2,3-dihydro-1H-indol-6-yl]-5,5-dimethyl-imidazolidine-2,4-dione obtained in stage a) of Example 31B in 10 mL of dioxane are successively added, under argon, 33 mg of N,N-dimethylurea, 29 mg of (9,9-dimethyl-9H-xanthene-3,6-diyl)bis(diphenylphosphine) (Xantphos), 22 mg of palladium acetate and 652 mg of caesium carbonate. The reaction mixture is refluxed for 6 hours, cooled to room temperature, filtered and washed with three times 10 mL of dichloromethane, and the filtrate is concentrated under reduced pressure. The residue is triturated in 20 mL of water and the precipitate formed is filtered off and purified twice by chromatography on a column of silica, eluting with a mixture of dichloromethane and methanol (93/7 by volume) to give 40 mg of 3-[4-({3-[1-(N,N-dimethylglycyl)-3,3-dimethyl-2,3-dihydro-1H-indol-6-yl]-5,5-dimethyl-2,4-dioxoimidazolidin-1-yl}methyl)-pyridin-2-yl]-1,1-dimethylurea, the characteristics of which are as follows:
