反应详情

5-Aminomethyl-4-[(3-fluorophenyl)hydrazono]-4H-pyrazol-3-ylamine (60 mg, 0.25 mmole) was dissolved in 3 mL of anhydrous DMF. To this solution was added triethylamine (0.51 mmole, 52 mg) and then a solution of maleic anhydride (30.2 mg, 0.31 mmole) in 1 mL of DMF. The reaction mixture was stirred at ambient temperature for 30 minutes and then worked up by the addition of saline and ethyl acetate. The mixture was acidified with 1 mL of 1.5 M HCl. The aqueous phase was extracted with ethyl acetate. The combined organic layer was washed with saline three times and dried over anhydrous MgSO4. The solution was then filtered, concentrated and purified by preparative TLC (CH2Cl2:MeOH:trace acetic acid=6:1) to yield 58 mg of the title compound as a yellow powder. MS (m/z, ES−): 331 (M−1, 100%); 1H NMR (ppm, 300 MHz, DMSO-d6) □δ 11.90 (br s, 1H), 7.35-7.70 (m, 3H), 7.30 (br s, 2H), 6.12 (d, 1H), 5.70 (d, 1H), 4.52 (s, 2H).

1. extractionThe aqueous phase was extracted with ethyl acetate
2. washThe combined organic layer was washed with saline three times
3. dry with materialdried over anhydrous MgSO4
4. filtrationThe solution was then filtered
5. concentrationconcentrated
6. custompurified by preparative TLC (CH2Cl2:MeOH:trace acetic acid=6:1)