[H-].[Na+].[NH2:3][C:4]1[N:5]=[N:6][CH:7]=[CH:8][CH:9]=1.[N+](C1C=CC([O:19][C:20]([N:22]2[CH2:25][CH:24]([O:26][C:27]3[CH:32]=[CH:31][C:30]([Br:33])=[CH:29][N:28]=3)[CH2:23]2)=O)=CC=1)([O-])=O.C(=O)(O)[O-].[Na+]>CN(C=O)C>[N:6]1[CH:7]=[CH:8][CH:9]=[C:4]([NH:3][C:20]([N:22]2[CH2:23][CH:24]([O:26][C:27]3[CH:32]=[CH:31][C:30]([Br:33])=[CH:29][N:28]=3)[CH2:25]2)=[O:19])[N:5]=1
To an ice-bath cooled solution of sodium hydride (60 wt % in mineral oil, (0.946 g, 23.6 mmol) in DMF (21 mL) under nitrogen atmosphere was added (dropwise) a solution of 3-aminopyridazine (1.24 g, 13.01 mmol) in DMF (21 mL). After several minute a solution of 3-(5-bromo-pyridin-2-yloxy)-azetidine-1-carboxylic acid 4-nitro-phenyl ester (Example 10, step 3; 4.66 g, 11.83 mmol) in DMF (17 mL) was added. After 5 min the cooling bath was removed and reaction allowed to warm to ambient temperature and stir for 1.5 hr. Saturated sodium bicarbonate solution (500 mL) was added and the mixture was extracted with EtOAc (4×400 mL). Combined organic phases were washed with sat sodium chloride solution (500 mL), dried over sodium sulphate and filtered. The filtrate solvents were removed in vacuo to afford a crude product that was triturated with diethyl ether to afford the title compound (3.32 g, 80%) as a colourless solid.
読み込み中…
