[Na].[C:2]([O:12]CC)(=[O:11])[CH2:3][C:4]([C:6]([O:8]CC)=O)=O.[OH-].[Na+].Cl.[Cl:18][C:19]1[CH:24]=[CH:23][C:22]([C:25](=[NH:27])[NH2:26])=[CH:21][CH:20]=1.Cl>O>[Cl:18][C:19]1[CH:24]=[CH:23][C:22]([C:25]2[NH:27][C:6](=[O:8])[CH:4]=[C:3]([C:2]([OH:12])=[O:11])[N:26]=2)=[CH:21][CH:20]=1To a mixture of diethyl oxalacetate sodium salt (123.2 g, 586 mmol) in water (750 mL) was slowly added aqueous sodium hydroxide (50%, 47 g, 586 mmol). After 1 h the solids had dissolved. 4-Chlorobenzenecarboximidamide monohydrochloride (111.95 g, 586 mmol) was then added, and the mixture was heated at 70° C. overnight. After cooling to room temperature concentrated hydrochloric acid was slowly added (causing foaming) until the pH was lowered to 1.5. The solid was isolated by filtration and washed with water and methanol. The solid was then triturated twice with hot methanol, washed repeatedly with 1 N hydrochloric acid, then once with methanol and dried to afford the title compound (66.07 g).
불러오는 중…