Combine 1-[3-(3,4-dichloro-phenyl)-pyrrolidin-3-yl]-ethyl]-4-phenyl-piperidine-4-carboxylic acid amide hydrochloride (241 mg, 0.41 mmol), 3,5-dibromo-4-methoxy-benzoic acid (0.23 g, 0.75 mmol), N,N-diisopropylethylamine (0.75 mmol), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) (0.75 mmol), and 1-hydroxy-benzotriazole hydrate (HOBT) (0.75 g, 1.1 mmol) in dichloromethane (10 mL). After 18 hour, dilute with dichloromethane and extract with 1M hydrochloric acid solution, 5% sodium bicarbonate solution, and water. Dry the organic layer over MgSO4, filter, and evaporate in vacuo to give a residue. Chromatograph the residue on silica gel eluting sequentially with 50% ethyl acetate/hexane and then 6% methanol/dichloromethane to give the title compound: Rf =0.35 (silica gel, 10% methanol/dichloromethane).
