[OH-].[K+].C([O:5][C:6]([C:8]1[CH:9]=[N:10][N:11]([C:13]2[NH:22][C:21](=[O:23])[C:20]3[C:15](=[CH:16][C:17]([N:24]([CH3:26])[CH3:25])=[CH:18][CH:19]=3)[N:14]=2)[CH:12]=1)=[O:7])C.C(OC(C1C=NN(C2NC(=O)C3C(=CC=CC=3N(C)C)N=2)C=1)=O)C.CN(C)C1C=CC=C2C=1C(=O)NC(N1C=C(C(O)=O)C=N1)=N2>C1COCC1>[CH3:25][N:24]([CH3:26])[C:17]1[CH:16]=[C:15]2[C:20]([C:21](=[O:23])[NH:22][C:13]([N:11]3[CH:12]=[C:8]([C:6]([OH:7])=[O:5])[CH:9]=[N:10]3)=[N:14]2)=[CH:19][CH:18]=1Aqueous 1M KOH (3.8 mL, 3.8 mmol) was added to a 3:2 mixture of 1-(7-dimethylamino-4-oxo-3,4-dihydro-quinazolin-2-yl)-1H-pyrazole-4-carboxylic acid ethyl ester and 1-(5-dimethylamino-4-oxo-3,4-dihydro-quinazolin-2-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (0.415 g, 1.27 mmol) in THF (3.8 mL). The reaction mixture was allowed to stir at room temperature for 18 h and was then concentrated. The residue was re-dissolved in water (10 mL) and acidified with 1M aqueous HCl (3 mL). The resulting precipitate was collected by filtration to yield a mixture of the titled compound and 1-(5-dimethylamino-4-oxo-3,4-dihydro-quinazolin-2-yl)-1H-pyrazole-4-carboxylic acid. The collected precipitate was triturated from DMSO and rinsed with ethanol to yield pure 1-(7-dimethylamino-4-oxo-3,4-dihydro-quinazolin-2-yl)-1H-pyrazole-4-carboxylic acid (0.113 mg, 29% yield). The filtrate was saved for further purification. MS (ESI/Cl): mass calcd. for C14H13N5O3, 299.1; m/z found, 300.1 [M+H]+. 1H NMR (400 MHz, DMSO-d6): 12.97 (s, 1H), 12.21 (s, 1H), 8.92 (s, 1H), 8.22 (s, 1H), 7.90 (d, J=8.9 Hz, 1H), 6.93 (dd, J=9.0, 2.3 Hz, 1H), 6.72 (s, 1H), 3.07 (s, 6H).
読み込み中…
