To a stirred solution of 2-methoxyterephthalic acid 4-methyl ester (450 mg, 2.1 mmol; prepared as described in Preparation 18) in DMF (10 mL) was added EDC (630 mg, 3.3 mmol), HOAt (2.4 mL, 1.18 mmol, 0.5M in DMF) and DIPEA (1.3 mL, 7.05 mmol). When the mixture was homogenous, a solution of biphenyl-2-ylcarbamic acid 1-(2-methylaminoethyl)piperidin-4-yl ester (830 mg, 2.4 mmol; prepared as described in Preparation 4) was added slowly. The reaction mixture was stirred at room temperature for 16 hours and then washed with water (100 mL), 1N HCl (100 mL), 1N NaOH (100 mL), brine (100 mL), dried over MgSO4, filtered and concentrated to afford the title intermediate in 89% yield (1.04 g, 1.9 mmol). MS m/z: [M+H+] calcd for C31H35N3O6, 545.6. found, 546.6.
