反应详情

To the compound (0.26 g, 0.58 mmol) obtained in Step (i) was added trifluoroacetic acid (4 ml), and the mixture was stirred at room temperature for 20 minutes. Trifluoroacetic acid was evaporated with an evaporator, and to the resultant were added THF (10 ml), benzyl bromide (0.21 ml, 1.74 mmol) and ethyl diisopropylamine (0.75 ml, 4.35 mmol), and the mixture was stirred at room temperature for 15 hours, then stirred at 50° C. for one hour. The resultant was concentrated by an evaporator, and water was added to the residue. The mixture was extracted three times with chloroform, dried over magnesium sulfate, and concentrated. The residue was purified by silica gel column (chloroform/methanol=100/1 to 20/1). Then, methanol (1 ml) and a 4N hydrochloric acid in dioxane (1 ml) were added thereto, and the mixture was stirred at room temperature for one hour. The mixture was cooled to 0° C., and neutralized with 4% aqueous ammonia. The precipitated solid was collected by filtration, and washed with water to give the title compound (55 mg, 0.13 mmol) as a white solid. Yield: 22%.

1. customTrifluoroacetic acid was evaporated with an evaporator
2. stirringthe mixture was stirred at room temperature for 15 hours
3. stirringstirred at 50° C. for one hour
4. concentrationThe resultant was concentrated by an evaporator, and water
5. additionwas added to the residue
6. extractionThe mixture was extracted three times with chloroform
7. dry with materialdried over magnesium sulfate
8. concentrationconcentrated
9. customThe residue was purified by silica gel column (chloroform/methanol=100/1 to 20/1)
10. additionThen, methanol (1 ml) and a 4N hydrochloric acid in dioxane (1 ml) were added
11. stirringthe mixture was stirred at room temperature for one hour
12. temperatureThe mixture was cooled to 0° C.
13. filtrationThe precipitated solid was collected by filtration
14. washwashed with water