Journal of Medicinal Chemistry Table 8. continued Article LC-MS: (ES, m/z) [M + H]+ calcd for C27H32F2N5O3, 512; found, 512. The Boc compound was treated with 20% TFA in CH2Cl2 (50 mL) and was added to the mixture. After the completion of this reaction (monitored by LCMS), the resulting mixture was concentrated under reduced pressure. The resulting residue was puriﬁed by reverse phase HPLC to yield product as a TFA salt. The acetonitrile−water layer was concentrated in vacuo to remove all the solvents. The residue was dissolved in dichloromethane and carefully neutralized by satd NaHCO3. The organic layer was successively washed with brine fol- lowed by water. The organic layer was concentrated to yield 22 (450 mg, 52%). LC-MS: (ES, m/z) [M + H]+ calcd for C22H23F2N5O, 412.2; found, 412.1. 1H NMR (MeOH-d4, 400 Hz) δ 7.61−7.57 (m, 2H), 6.94 (t, J = 8.8 Hz, 2H), 6.81 (t, J = 8.8 Hz, 2H), 6.47 (m, 2H), 3.72 (m, 2H), 3.58 (m, 2H), 3.42 (m, 2H), 1.85 (s, 6H). Elemental analysis compound 22 with 0.65 equiv H2O: C, 62.44; N, 16.55; H, 4258 dx.doi.org/10.1021/jm300041e | J. Med. Chem. 2012, 55, 4244−4273