反应详情

To one gram of 8-chloro-7-fluoro-5-oxo-1,2-dihydro-5H-thiazolo(3,2-a)quinoline-4-carboxylic acid (33 mmol) were added 2.87 grams (33 mmol) of anhydrous piperazine and 30 ml of pyridine and the resulting suspension was heated to reflux for twelve hours in an oil bath. Pyridine was evaporated therefrom under reduced pressure, water was added to the residue, and the mixture was again concentrated under reduced pressure. Water was added to the resulting residue, then 4 ml of 2 N aqueous solution of sodium hydroxide was added thereto, and the mixture was warmed to prepared uniform solution. Then this was adjusted to pH nearly seven with 1 N hydrochloric acid. Crystals separated out therefrom were collected by filtration, washed with water, washed with acetone and ether, and air dried to give the title product as powdery crystals. Yield 997.8 mg (90.7 percent). Melting point 287° to 288° C. (decomposition). Elementary analysis calculated as C16H16FN3O3S.3H2O: C 47.64, H 5.50, N 10.41; Found: C 47.60, H 5.42, N 10.63.

1. temperaturethe resulting suspension was heated
2. temperatureto reflux for twelve hours in an oil bath
3. customPyridine was evaporated
4. additionunder reduced pressure, water was added to the residue
5. concentrationthe mixture was again concentrated under reduced pressure
6. additionWater was added to the resulting residue
7. addition4 ml of 2 N aqueous solution of sodium hydroxide was added
8. temperaturethe mixture was warmed
9. customto prepared uniform solution
10. customCrystals separated out
11. filtrationtherefrom were collected by filtration
12. washwashed with water
13. washwashed with acetone and ether, and air
14. customdried