[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[O:14][C:13]3[C:12](=[O:15])[CH:11]=[C:10]([C:16]([O:18]C)=[O:17])[NH:9][C:8]=3[C:7](=[O:20])[C:6]=2[CH:21]=1>[OH-].[Na+]>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[O:14][C:13]3[C:12](=[O:15])[CH:11]=[C:10]([C:16]([OH:18])=[O:17])[NH:9][C:8]=3[C:7](=[O:20])[C:6]=2[CH:21]=1A suspension of methyl 8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-2-carboxylate (1 g, 0.0034 mole) in 1N sodium hydroxide solution (20 ml) was stirred at room temperature for 24 hrs. The solid was filtered off, washed with water, with acetone, and suspended in 5N hydrochloric acid. The product was filtered off, washed with water, with acetone, and sucked dry. Recrystallization from DMF gave white crystals (0.775 g, 81%), m.p. 290°-320° (dec.).
Wird geladen…