A solution of [5-(3,4-dichloro-benzenesulfonyl)-8-fluoro-5,6-dihydro-phenanthridin-6-yl]-acetic acid (210 mg, 0.45 mmol), triethylamine (0.07 mL, 1.5 mmol) and N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (0.19 g, 0.5 mmol) in dry dimethyl formamide (5 mL) was stirred at room temperature for five minutes before 2-[4-(4,5-dihydro-1H-imidazol-2-yl)-phenyl]-ethylamine dihydrochloride (Reference Example 2) (131 mg, 0.5 mmol) was added. The pH of the reaction mixture was adjusted to 8 by addition of triethylamine, the so obtained mixture was stirred at room temperature overnight, then concentrated in vacuo. The residue was purified by preparative thin-layer chromatography (dichloromethane:methanol:NH4OH=5:1:0.1) to yield 382 mg (75%) of the title compound as white crystals.
