(26) A solution of compound (25) (1.2 g, 5.5 mmol), 4-fluorobenzylzinc chloride (13.1 mL, 0.5 M in THF, 6.6 mmol), tetrakis(triphenylphosphine)palladium (0.13 g, 0.1 mmol) in THF (50 mL) was heated to refluxed for 3 hours under nitrogen. After it cooled to room temperature, the THF was removed in vacuo. The residue was diluted with ethyl acetate, washed with water and brine, dried over Na2SO4. After concentrated, the residue was purified by a column chromatography on silica gel eluting with 5% ethyl acetate in hexane to yield 2-(4-fluoro-benzyl)-4,6-dimethoxy-5-nitro-pyrimidine (26) (1.1 g, 63%). 1H NMR (CDCl3)
