反应详情

3-[3-(2-methoxy-phenyl)-1H-pyrazolo[3,4-b]pyridin-5-yl]-benzoic acid (338 mg, 0.79 mmol) and O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (300 mg, 0.79 mmol) were dissolved in a mixture of 20 ml of acetonitrile and 10 ml of methanol. 131 mg (0.83 mmol) of 1-(2-dimethylaminoethyl)-piperazine was added and the mixture stirred at ambient temperature for 6 h. The resulting mixture was distributed between dichloromethane and a 2 M aqueous solution of sodium carbonate. The phases were separated and the aqueous layer extracted three times with dichloromethane. The combined organic layers were combined, washed with a saturated aqueous solution of sodium bromide, dried over sodium sulfate, and evaporated. The crude material was purified by flash chromatography on silica gel using a stepped gradient of ethyl acetate and a 4:4:1 solvent mixture of ethyl acetate, dichloromethane and methanol containing 2% v/v of 35% wt ammonia in water to afford [4-(2-dimethylamino-ethyl)-piperazin-1-yl]-{3-[3-(2-methoxy-phenyl)-1H-pyrazolo[3,4-b]pyridin-5-yl]-phenyl}-methanone (160 mg, 42%) as an oil. 1H-NMR (d6-CDCl3) δ: 8.87 (d) [1H], 8.36 (d) [1H], 7.75 (dd) [1H], 7.68 (t) [1H], 7.67 (m) [1H], 7.53 (m) [1H], 7.46 (mt) [1H], 7.42 (md) [1H], 7.13 (dt) [1H], 7.10 (d) [1H], 3.89 (s) [3H], 3.81-3.86 (m) [2H], 3.48-3.55 (m) [2H], 2.58-2.64 (m) [2H], 2.56 (m) [2H], 2.50 (m) [2H], 2.44-2.52 (m) [2H]. MS: m/z 485 (M+H+).

1. customThe phases were separated
2. extractionthe aqueous layer extracted three times with dichloromethane
3. washwashed with a saturated aqueous solution of sodium bromide
4. dry with materialdried over sodium sulfate
5. customevaporated
6. customThe crude material was purified by flash chromatography on silica gel using a stepped gradient of ethyl acetate
7. additiona 4:4:1 solvent mixture of ethyl acetate, dichloromethane and methanol containing 2% v/v of 35% wt ammonia in water