Silver carbonate (317 mg, 1.15 mmol), triphenylphosphine (16 mg, 0.06 mmol) and Pd(dppf)Cl2.CH2Cl2 (24 mg, 5 mole %) were stirred together at room temperature under nitrogen. 5-Bromo-2-phenylpyrimidine (163 mg, 0.69 mmol) was added followed by 2-phenyl-oxazole (84 mg, 0.58 mmol; prepared according to Ohnmacht, S. A. et al., Chemical Communications, 2008, 1241-1243). Finally water (6 mL) was added and the mixture heated for 18 hours at 60° C. The mixture was cooled to room temperature and filtered through Celite washing with DCM and acetone. Purification by silica gel flash chromatography (100% DCM) through a 12-g Silicycle® flash silica cartridge gave title compound as light yellow solid (19 mg, 11% yield); Rf 0.68 with DCM; melting point 228-231° C.; 1H-NMR (300 MHz; DMSO-d6) δ 9.39 (s, 2H), 8.45 (dd, 2H), 8.17 (dd, 2H), 8.11 (s, 1H), 7.54-7.65 (m, 6H); MS (ESI+) m/z 300 (M+1), (ESI−) m/z 298 (M−1); H-PGDS FPBA IC50: 125 μM.
