To a flask was added 5-[4-(2,4-bis-trifluoromethyl-benzyloxy)-3-methoxy-benzyl]-2-thioxo-thiazolidin-4-one from Step A (140 mg, 282 μmol), DMSO (1 mL) and iodomethane (2 mL). The reaction solution was allowed to stir under N2 for 3 h. The excess iodomethane was removed in vacuo. To the reaction mixture was added MeCN (6 mL) and N-methyl piperazine (95 μL, 850 μmol). The reaction solution was stirred at 55° C. for 2 h. The reaction solution was then diluted with EtOAc (200 mL), washed with aq. NH4Cl and water, dried over Na2SO4 and concentrated. The crude material was chromatographed (SiO2, DCM/MeOH 100:0 to 90:10) to provide title compound (55 mg, 35% yield). 1H NMR (CDCl3) δ 8.10 (1H, d, J=8.1 Hz), 7.92 (1H, s), 7.83 (1H, d, J=8.1 Hz), 6.83 (1H, s), 6.73 (2H, br s), 5.36 (2H, s), 4.46 (1H, dd, J1=3.6 Hz, J2=10.4 Hz), 3.96 (2H, t, J=4.9 Hz), 3.90 (3H, s), 3.57 (1H, dd, J=3.6 Hz, J2=14.3 Hz), 3.49 (2H, t, J=4.9 Hz), 2.92 (1H, dd, J1=10.4 Hz, J2=14.3 Hz), 2.46 (4H, m), 2.32 (3H, s); MS (ESI) 562 (MH+).
