To a solution of 2-{3-[(2,2-difluoro-2-phenylethyl)amino]-6-chloro-2-fluorophenyl}acetic acid (516 mg, 1.5 mmol), as prepared in step 15 of Example 1, in DMF (8.0 mL) was added N-[5-(aminomethyl)-6-methyl (2-pyridyl)](tert-butoxy) carboxamide (498 mg, 2.1 mmol) (Sanderson, P. E., et al., WO 97/01338 (1997)), BOP (1.06 g, 2.4 mmol), and DIEA (0.78 mL, 4.5 mmol). After stirring for 18 hours, additional amine (107 mg, 450 μmol) was added, and the mixture continued to stir for 18 hours. The solvents were evaporated, and the reaction mixture was partitioned between DCM and saturated NaHCO3. The organic layer was separated, and the aqueous layer extracted with DCM. The organic layers were combined, washed with 10% KHSO4 (2 times), H2O, and brine, dried over Na2SO4, concentrated, and flash chromatographed on silica gel eluting with MeOH/DCM (0, 1.5, and 2.5%) to give the title compound (770 mg, 91% yield) as a pale brown foam. 1H-NMR (400 MHz, CDCl3) δ 7.66 (d, J=8.4 Hz, 1H), 7.51-7.41 (m, 6H), 7.23 (bs, 1H), 7.01 (dd, J=8.8, 1.5 Hz, 1H), 6.57 (t, J=9.0 Hz, 1H), 5.64 (br s, 1H), 4.37 (d, J=5.6 Hz, 2H), 4.26-4.22 (m, 1H), 3.79-3.70 (m, 4H), 2.35 (s, 3), 1.50 (s, 9H). Mass spectrum (LCMS, ESI) calc'd for C28H31ClF3N4O3 (M+H): 563.2. Found: 562.9.
