A solution of N1-(4-methoxybenzoyl)-N2-(piperidin-4-ylcarbonyl)-1,2-benzenediamine (180 mg, 0.510 mmol) and α-bromo-p-tolunitrile (104 mg, 0.530 mmol) in acetonitrile (5 mL) was treated with potassium carbonate and the resulting mixture was heated at reflux for 2 h. The mixture was poured into a mixture of ethyl acetate and water. The organic layer was concentrated in vacuo, the residue dissolved in 10% acetic acid/methanol, and the resulting solution loaded onto an ion exchange resin (SCX, Varian). Elution with methanol (4 column volumes) followed by 2 N ammonia in methanol (2 column volumes) and concentration of the appropriate fractions yielded 214 mg (90%) of the title compound.
