Reaction Steps
N-Ethylmethylamine (37 μL, 0.43 mmol) was added to a solution of Intermediate 96f (111 mg, 0.14 mmol) in THF (2 mL). The reaction was heated to 60° C. in a sealed vial overnight. N-Ethylmethylamine (37 μL, 0.43 mmol) was added and the reaction continued for a further 24 h. The mixture was cooled, evaporated in vacuo and the residue was purified by FCC, using 0-15% MeOH in DCM, then triturated with Et2O. Further purification by HPLC (Gemini C, 18 column, 10-98% MeCN in H2O, 0.1% formic acid) followed by evaporation of the fractions and trituration with Et2O gave the title compound (12 mg, 11%) as an off-white solid. LCMS (Method 5): Rt 3.85 min, m/z 734.6 [MH+]. 1H NMR (400 MHz, d6-DMSO): 0.55 (3H, d, J=6 Hz), 0.58 (3H, d, J=6 Hz), 0.89 (3H, t, J=7.0 Hz), 1.23 (9H, m), 1.33-1.57 (3H, m), 1.62-1.70 (2H, m), 1.71-1.95 (3H, m), 1.96-2.09 (2H, m), 2.13 (3H, s), 2.35 (2H, q, J=7.2 Hz), 2.63 (2H, t, J=5.7 Hz), 3.06-3.20 (3H, m), 3.21-3.36 (2H, m, obscured by solvent), 4.03 (2H, t, J=5.7 Hz), 4.74-4.83 (1H, m), 5.48 (1H, t, J=5.5 Hz), 6.28 (1H, s), 6.88-6.94 (1H, m), 7.00-7.10 (3H, m), 7.16 (1H, dd, J=9.8, 2.0 Hz), 7.18-7.26 (2H, m), 7.26-7.32 (2H, m), 7.35 (1H, t, J=8.0 Hz), 7.62 (1H, d, J=9.8 Hz), 7.81-7.86 (1H, m), 8.09 (1H, s), 8.37 (0.2H, s).
