Example 51
In a dry single-necked flask, Compound 36-4 (300 mg), Compound 52-1 (129 mg), sodium carbonate (102 mg), 1,2-dichloroethane (2.1 mL), and water (0.9 mL) were added. After nitrogen purge, dichlorobis(triphenylphosphine)palladium (40 mg) was added, and the resulting mixture was refluxed at 100° C. and reacted for 16 h. The reaction mixture was concentrated, and the residue obtained from the concentration was purified successively by a preparative TLC plate and preparative HPLC method to obtain Compound 52. 1H NMR (400 MHz, CDCl3) δ ppm 9.52-9.55 (m, 1H), 8.93 (d, J=2.89 Hz, 1H), 7.98-8.04 (m, 2H), 7.92 (d, J=0.88 Hz, 1H), 7.86-7.91 (m, 1H), 7.59 (dd, J=9.91, 2.13 Hz, 1H), 6.60 (dd, J=2.89, 1.63 Hz, 1H), 3.20 (q, J=7.53 Hz, 2H), 1.73 (s, 5H), 1.67-1.77 (m, 1H), 1.50 (t, J=7.59 Hz, 3H). LCMS (ESI) m/z: 554 (M+1).
