[C:1]([O:5][CH2:6][CH3:7])(=[O:4])[NH:2][NH2:3].[CH3:8][N:9]1[CH:13]=[C:12]([CH:14]=O)[C:11]([C:16]2[O:17][C:18]([N+:21]([O-:23])=[O:22])=[CH:19][CH:20]=2)=[N:10]1.C(O)(=O)C.O>C(O)C>[CH2:6]([O:5][C:1]([NH:2][N:3]=[CH:14][C:12]1[C:11]([C:16]2[O:17][C:18]([N+:21]([O-:23])=[O:22])=[CH:19][CH:20]=2)=[N:10][N:9]([CH3:8])[CH:13]=1)=[O:4])[CH3:7]Add a solution of 19.5 g of ethyl carbazate in 250 ml of ethanol dropwise to 35 g of 1-methyl-3-(5-nitro-2-furyl)pyrazole-4-carboxaldehyde and 1 ml of glacial acetic acid in 400 ml of ethanol. Stir the resulting reaction mixture for 80 minutes at from 35° to 40° C, and add 650 ml of water dropwise to the thus-obtained suspension at room temperature. Cool in an ice bath and separate the produced precipitate by vacuum filtration. Wash the residue with ethanol/water (1:1) and with water to obtain a 97% yield of 1-methyl-3-(5-nitro-2-furyl)pyrazole-4-carboxaldehyde-ethoxycarbonylhydrazone [m.p. 217.5° to 219° C (with decomposition)].
読み込み中…