[OH:1][C:2]1[NH:6][N:5]=[C:4]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[CH:3]=1.C(=O)([O-])[O-].[K+].[K+].Cl[CH:19]1[CH2:24][CH2:23][CH2:22][CH2:21][C:20]1=[O:25]>C(#N)C>[CH2:10]([O:9][C:7]([C:4]1[CH:3]=[C:2]([O:1][CH:19]2[CH2:24][CH2:23][CH2:22][CH2:21][C:20]2=[O:25])[NH:6][N:5]=1)=[O:8])[CH3:11]To the stirred suspension of ethyl 5-hydroxy-1H-pyrazole-3-carboxylate (6.25 g, 40 mmol) and 22.1 g of potassium carbonate in 500 ml of acetonitrile was added 6.35 g of 2-chlorocyclohexanone, and refluxed for 16 hours. The reaction mixture was allowed to cool to room temperature, then filtered, the solid was washed with acetonitrile. The filtrate was concentrated to an oil. The residue was dissolved in ethyl acetate and extracted with water. The organic phase was dried over MgSO4 and evaporated to dryness. The product was purified by silics-gel column chromatography by eluting it with 1:1 ethyl acetaet;hexane. 4.92 g (49%) of the desired product was obtained as a white solid. M.Pt. 122–124° C.; (M+H) 253.
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