To a solution of 4-(benzyloxy)-2-(1H-pyrazol-1-yl)pyrimidine-5-carboxylic acid, 3-c, (2 g, 6.76 mmol) in dry THF (40 ml) and toluene (40 ml) were added Et3N (2.04 g, 20.3 mmol), DPPA (2.04 g, 7.43 mmol) and benzyl alcohol (1.1 g, 10.1 mmol). The resulting mixture was heated at 60° C. for 12 hours. The mixture was concentrated under vacuum and the residue was purified on silica gel column with the eluent of ethyl acetate/petroleum ether=1/5 (Rf=0.6) to provide the compound, 3-d (1.96 g, 72.6%). 1H NMR (DMSO-d6, 300 MHz): δ 9.39 (br, 1H), 8.73 (s, 1H), 8.62 (s, 1H), 7.83 (s, 1H), 7.56 (m, 2H), 7.33 (m, 8H), 6.57 (m, 1H), 5.58 (s, 2H), 5.16 (s, 2H).
