A solution of compound 94 (1.00 g, 2.88 mmol) and 3-(S)(−)aminopyrrolidine (495 mg, 5.75 mmol) in DMSO (5 ml) was heated to 80° C. for 3 h. The reaction mixture was cooled to room temperature and stirred for an additional 16 h and diluted with water. The aqueous solution was extracted with AcOEt/dichloromethane mixture, washed with saturated aqueous NaHCO3 and brine, dried over MgSO4, filtered and concentrated in vacuo to afford the title compound 153 as an orange solid (981 mg, 86% yield). 1H NMR: (DMSO) δ (ppm): 8.76 (s, 2H), 4.26 (q, J=7.1 Hz, 2H), 3.70-3.53 (m, 4H), 3.26 (dd, J=11.3, 3.9 Hz, 1H), 2.07-1.98 (m, 1H), 1.75-1.67 (m, 3H), 1.29 (t, J=7.0 Hz, 3H). LRMS (ESI): (calc.) 397.2; (obt.) 398.3 (M+H)+.
