[NH2:1][C:2]1[CH:7]=[C:6]([CH3:8])[C:5]([CH3:9])=[CH:4][C:3]=1[NH:10][C:11]([C:13]1[C:17]([N+:18]([O-:20])=[O:19])=[CH:16][NH:15][N:14]=1)=O>C(O)(=O)C>[CH3:9][C:5]1[C:6]([CH3:8])=[CH:7][C:2]2[NH:1][C:11]([C:13]3[C:17]([N+:18]([O-:20])=[O:19])=[CH:16][NH:15][N:14]=3)=[N:10][C:3]=2[CH:4]=1A stirred solution of 4-nitro-1H-pyrazole-3-carboxylic acid (2-amino-4,5-dimethylphenyl)amide [5.7 g, Reference Example 36(a)] in acetic acid (100 mL) was heated at 120° C. for 1 hour, then cooled to ambient temperature and then evaporated. The oily residue was partitioned between ethyl acetate and water. The organic layer was dried over magnesium sulfate and then evaporated to give 5,6-dimethyl-2-(4-nitro-1H-pyrazol-3-yl)-1H-benzoimidazole (5.70 g) as an orange solid. LC-MS (METHOD B): RT=2.30 minutes, 258.11 (M+H)+.
불러오는 중…