反应详情

A portion (0.20 g) of the compound obtained in Example 41 and ethylenediamine (0.54 ml) were suspended in a mixed solvent of methanol (3 ml) and methylene chloride (3 ml) and to the suspension was added sodium cyanoborohydride (61 mg). The mixture was stirred for 13 hours at room temperature and heated to reflux for further 20 hours. The reaction mixture was concentrated under reduced pressure. Water was added to the residue, followed by extraction with three portions of methylene chloride. The organic layers were combined, washed with saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. Then, the solvent was distilled off under reduced pressure and the residue was purified by silica gel column chromatography (methylene chloride/methanol=19:1-9:1-4:1). The resulting brown foam was dissolved in a solution (3 ml) of 10% hydrochloric acid in methanol and the solution was concentrated. The concentrate was crystallized from ether to yield 93 mg (32%) of the titled compound as brown crystals.

1. temperatureheated
2. temperatureto reflux for further 20 hours
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. additionWater was added to the residue
5. extractionfollowed by extraction with three portions of methylene chloride
6. washwashed with saturated aqueous solution of sodium chloride
7. dry with materialdried over anhydrous sodium sulfate
8. distillationThen, the solvent was distilled off under reduced pressure
9. customthe residue was purified by silica gel column chromatography (methylene chloride/methanol=19:1-9:1-4:1)
10. dissolutionThe resulting brown foam was dissolved in a solution (3 ml) of 10% hydrochloric acid in methanol
11. concentrationthe solution was concentrated
12. customThe concentrate was crystallized from ether