Reaction SMILES: [H-].[Na+].[OH:3][CH:4]1[C:12]2[C:7](=[CH:8][CH:9]=[CH:10][CH:11]=2)[C:6](=[O:13])[N:5]1[C:14]1[CH:23]=[CH:22][C:21]2[C:16](=[N:17][C:18]([O:24][CH3:25])=[CH:19][CH:20]=2)[N:15]=1.[CH3:26][N:27]([CH2:29][CH2:30]Cl)[CH3:28].[C:32]([OH:39])(=[O:38])/[CH:33]=[CH:34]/[C:35]([OH:37])=[O:36]>CN(C)C=O.C1(C)C=CC=CC=1.C(O)C>[C:32]([OH:39])(=[O:38])/[CH:33]=[CH:34]/[C:35]([OH:37])=[O:36].[CH3:26][N:27]([CH3:28])[CH2:29][CH2:30][O:13][CH:6]1[C:7]2[C:12](=[CH:11][CH:10]=[CH:9][CH:8]=2)[C:4](=[O:3])[N:5]1[C:14]1[CH:23]=[CH:22][C:21]2[C:16](=[N:17][C:18]([O:24][CH3:25])=[CH:19][CH:20]=2)[N:15]=1
Reactant: CN(C)CCCl
Reactant: COc1ccc2ccc(N3C(=O)c4ccccc4C3O)nc2n1
Agent: O=C(O)/C=C/C(=O)O
Agent: [H-]
Agent: [Na+]
Solvent: CN(C)C=O
Solvent: Cc1ccccc1
Solvent: CCO
Product: COc1ccc2ccc(N3C(=O)c4ccccc4C3OCCN(C)C)nc2n1
Temperature: 0 °C
Reaction time: 0.75 h

Procedure:
Sodium hydride (0.3 g) is added in small portions at a temperature in the region of 0° C. to a solution, maintained under an argon atmosphere, of 3-hydroxy-2-(7-methoxy-1,8-naphthyridin-2-yl)-1-isoindolinone (3.1 g) in anhydrous dimethylformamide (40 cc). The suspension obtained is stirred for 45 minutes at a temperature in the region of 0° C. and a 1.4M solution (8.5 cc) of N,N-dimethyl-2-chloroethylamine in toluene is then added. The reaction mixture is heated with stirring to a temperature of 65° C. for 4 hours, and is then cooled to a temperature in the region of 10° C., poured into distilled water (350 cc) and extracted with dichloromethane (3×50 cc). The organic phases are combined, washed with distilled water (4×30 cc), dried over magnesium sulphate, filtered and then concentrated to dryness under reduced pressure (2.7 kPa) at 40° C. Ethanol (8 cc) heated to 45° C. is added to the oily residue obtained. After removal of a solid by filtration, fumaric acid (1 g) is added to the filtrate and the mixture is heated until dissolution is complete. The solution obtained is cooled to a temperature in the region of 5° C. for 1 hour. The solid formed is separated by filtration, washed with ethanol (2×5 cc), cooled to a temperature in the region of 0° C., and then with diethyl ether (2×20 cc). Distilled water (200 cc) heated to 40° C. is added to the solid obtained. After removal of a solid by filtration, the filtrate is cooled to a temperature in the region of 10° C., saturated aqueous potassium bicarbonate solution is then added to a pH in the region of 9 and the mixture is extracted with ethyl acetate (3×120 cc). The organic phases are combined, washed with distilled water (3×50 cc), dried over magnesium sulphate, filtered and then concentrated to dryness under reduced pressure (2.7 kPa) at 60° C. The oily residue obtained is dissolved in ethanol (3 cc) heated to 45° C. Fumaric acid (0.4 g) is added to this solution and the mixture is heated until dissolution is complete. The solid obtained is cooled to a temperature in the region of 5° C. for 1 hour. The solid formed is separated by filtration, washed with ethanol (2×1 cc), cooled to a temperature in the region of 0° C., and then with diethyl ether (2×2 cc), and dried in the air. 3-(2-Dimethylaminoethoxy)-2-(7-methoxy-1,8-naphthyridin-2-yl)-1-isoindolinone fumarate (1.4 g), m.p. 205° C., is thereby obtained.