Isobutyl chloroformate → 5-(4-Chloro-phenyl)-6-(2,4-dichloro-phenyl)-1-(4-hydroxymethyl-phenyl)-1,5-dihydro-pyrazolo[3,4-d]pyrimidin-4-one

Beteiligte Stoffe

Reaktionsschritte

4-[5-(4-Chloro-phenyl)-6-(2,4-dichloro-phenyl)-4-oxo-4,5-dihydro-pyrazolo[3,4-d]pyrimidin-1-yl]-benzoic acid (115 mg, 0.225 mmol) is dissolved in 6 mL of THF. To the solution TEA (68.0 mg, 0.674 mmol) and isobutylchloroformate (46.0 mg, 0.337 mmol) are added and the mixture is stirred for 1.5 h. The resulting mixture is added to a solution of sodium borohydride (33.3 mg, 0.898 mmol) in 3 mL of water and then stirred for 3 h, concentrated, and extracted with water/ethyl acetate and purified by column chromatography. 1H NMR (dioxane, 400 MHz) δ 8.33 (s, 1H), 8.00 (d, 2H), 7.45 (s, 1H), 7.39 (d, 2H), 7.16 (d, 1H), 7.29-7.19 (m, 5H), 7.03 (m, 1H), 4.53 (d, 2H), 3.71 (t, 1H). HPLC-MS calculated for C24H15Cl3N4O2 (M+H+) 497.0, Found 497.0.

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