[C:1]1([C:7]2[N:11]3[CH:12]=[C:13]([C:20]([O:22]C)=[O:21])[C:14]4[C:19]([C:10]3=[CH:9][N:8]=2)=[CH:18][CH:17]=[CH:16][CH:15]=4)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[OH-].[Na+]>CO.O>[C:1]1([C:7]2[N:11]3[CH:12]=[C:13]([C:20]([OH:22])=[O:21])[C:14]4[C:19]([C:10]3=[CH:9][N:8]=2)=[CH:18][CH:17]=[CH:16][CH:15]=4)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1A slurry of the product from part 8 (488 mg) and NaOH (226 mg) in 15 ml of methanol and 10 ml of water is stirred at 60° C. until a solution forms. The methanol is then evaporated in vacuo, and the remaining mixture is diluted with water. After adjusting the pH to 5–6 with 1N HCl, the solid is collected by filtration, washed with water and dried to give the title compound (450 mg) as a yellow solid, m.p. 187–90° C.
Wird geladen…