1H NMR (400 MHz, CDCl3) δ 7.46 (d, J = 7.1 Hz, 8H), 7.35 (p, J = 6.3 Hz, 12H), 3.65 (t, J = 7.0 Hz, 4H), 1.70 (s, 4H), 1.42 (s, 4H). 13C{1H} NMR (101 MHz, CDCl3) δ 170.8, 136.1, 129.9, 129.7, 128.7, 128.5, 38.3, 28.5, 26.4. HRMS (EI) m/z: calcd for C38H32N2O4, 580.2362; found, 580.2364.