反应详情

To the compound obtained in Example 14 is added a mixture solution made up of 100 ml of 2N hydrochloric acid and 10 ml of ethanol, and the resulting mixture is refluxed for 4 hours while heating. After cooling, the reaction mixture is neutralized with 2N sodium hydroxide solution and concentrated under reduced pressure. The residue is added to water which is then adjusted to pH 13 with 2N sodium hydroxide solution to dissolve, and any undissolved matter, if present, is removed. The solution is adjusted to pH 7 with acetic acid. Precipitating crystals are collected by filtration and washed. To the washed crystals is added water, pH adjusted to 3 to dissolve, and any undissolved matter, if present, is removed. The solution is then adjusted to pH 7 with 2N sodium hydroxide solution and precipitating crystals are collected by filtration and washed with water. Recrystallization from DMF-methanol gives 1.07 g of the titled compound. Melting point 214°-216° C.

1. temperaturethe resulting mixture is refluxed for 4 hours
2. temperaturewhile heating
3. temperatureAfter cooling
4. concentrationconcentrated under reduced pressure
5. additionThe residue is added to water which
6. dissolutionto dissolve
7. customany undissolved matter, if present, is removed
8. customPrecipitating crystals
9. filtrationare collected by filtration
10. washwashed
11. additionTo the washed crystals is added water
12. dissolutionto dissolve
13. customany undissolved matter, if present, is removed
14. customprecipitating crystals
15. filtrationare collected by filtration
16. washwashed with water
17. customRecrystallization from DMF-methanol