To a stirred suspension of 3-[4-(4-tert-butyl-phenyl)-piperazin-1-yl]-2-methyl-propionic acid lithium salt (16 mg; 0.05 mmol) in tetrahydrofuran (1.0 mL) is added tetramethyl-O-(1H-benzotriazol-1-yl)uronium hexafluorophosphate (19 mg; 0.05 mmol) in dimethylformaide (0.5 mL). 15 minutes later, diisopropylethyl amine (25 μL; 0.15 mmol) and a solution of 4-(piperidin-4-ylamino)-2-trifluoromethyl-benzonitrile hydrochloride (15 mg; 0.05 mmol, prepared in accordance with Example 155) in dimethylformamide (0.5 mL) are added. After 2 hours at room temperature, aluminium oxide (90 active basic) is added and stiffing is continued. The solids are removed by filtration and the filtrate is concentrated under high vacuum. The obtained residue is purified by preparative HPLC to afford the desired compound (2 mg; 0.004 mmol). The structure was confirmed using Protocol I-D. Calculated mass=556; observed mass=556; HPLC retention time=1.60 min.
