反应详情

The compound 34-3 (60 mg) prepared according to the same procedure as described in Step 2 was dissolved in 50% aqueous tetrahydrofuran solution (10 ml) and to the solution was added lithium hydroxide (24 mg). The mixture was stirred at room temperature for 5 hours to hydrolyze the compound 34-3 and the solvent was removed therefrom. The residue was dissolved in ethyl acetate and extracted to the obtain the compound 34-4 (43 mg, 81%). The compound 34-4 was dissolved in benzene (2 ml) and to the solution was added dropwise oxalyl chloride (100 μl), followed by refluxing for 2 hours. The reaction mixture obtained by concentrating the resultant under reduced pressure and hydrochloride compound 3-4 (67 mg) prepared in Example 13 were added to dichloromethane (6 ml), and to the mixture was added triethylamine (60 μl), followed by stirring at room temperature for 2 hours. The resulting mixture was concentrated under reduced pressure and the obtained residue was purified by column-chromatography (ethyl acetate/hexane=1/1) to yield the compound 34-5 (34 mg, 38%).

1. customthe solvent was removed
2. dissolutionThe residue was dissolved in ethyl acetate
3. extractionextracted to the