Hydrochloric Acid → HCID 136092328, compound

Reaction equation

C([O:4][C:5]1[C:6]2[C:11]([CH:12]=[C:13]([O:17][CH3:18])[C:14]=1[O:15][CH3:16])=[N:10][C:9](=[O:19])[C:8](=[O:20])[N:7]=2)(=O)C.[OH-].[Na+].Cl>O>[OH:4][C:5]1[C:6]2[C:11]([CH:12]=[C:13]([O:17][CH3:18])[C:14]=1[O:15][CH3:16])=[N:10][C:9](=[O:19])[C:8](=[O:20])[N:7]=2

Participants

Procedure

5-Acetyloxy-6,7-dimethoxy-2,3-quinoxalinedione (47) (30 mg, 0.107 mmol) was added to a single-necked 15-mL flask. Sodium hydroxide aqueous solution (2N, 1 mL) was added to the flask under nitrogen with stirring. The solution was then stirred at room temperature for 24 h. The solution was diluted with water (3 mL) and then acidified with HCl (4N, 1 mL) to pH=2 to give a brown solid, which was collected by filtration and dried in vacuo, giving 23 mg (86%) of the title compound; mp 285°-286° C. (dec); 1H NMR (DMSO-d6, 300 MHz) δ3.688 (s, 3H), 3.694 (s, 3H), 6.227 (s, 1H), 9.769 (s, 1H), 11.016 (s, 1H), 11.658 (s, 1H). EIMS m/e 238 (100, M+), HPLC purity>96%.