To a solution of 7-chloro-3-methyl-pyrrolo[2,3-c]pyridine-1,4-dicarboxylic acid 1-tert-butyl ester (80 mg) in dimethylformamide (2 ml) was added 4-ethylmorpholine (131 μl), morpholine (46 μl), 1-hydroxybenzotriazole hydrate (54 mg) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (60 mg) and the solution stirred at room temperature overnight. The dimethylformamide was evaporated and the residue dissolved in ethyl acetate (20 ml). The organic layer was then washed with 5% sodium hydrogen carbonate solution (2×4 ml) and water (2×10 ml). The organic layer was dried (MgSO4) and evaporated to give a yellow oil (107 mg) which was used without further purification.
