반응 #52549

반응 방정식

NaOH

formic acid

9-Deoxo-9a-aza-9a-homoerythromycin A

formaldehyde

→

Azithromycin monohydrate

용매

acetonitrile

반응 조건

후처리

1. 1
   workup.ADDITIONwere added
2. 2
   온도refluxed for 24 hours
3. 3
   여과filtered
4. 4
   기타to remove particles
5. 5
   workup.ADDITIONTo the filtered acetonitrile solution, an equal volume of water was added
6. 6
   기타to precipitate Azithromycin monohydrate as cube
7. 7
   여과The crystals were filtered
8. 8
   기타dried under vacuum at 50° C.

실험 절차

9-Deoxo-9a-aza-9a-homoerythromycin A (73.5 g —0.1 mole) was dissolved in 250 ml acetonitrile. To this solution, formic acid (19 ml, 0.5 mole) followed by formaldehyde (37%, 20 ml, 0.25 mole) were added and refluxed for 24 hours. The pH of the reaction mixture was adjusted with alkali (NaOH solution) to 10.5 and filtered to remove particles. To the filtered acetonitrile solution, an equal volume of water was added to precipitate Azithromycin monohydrate as cube shaped crystals. The crystals were filtered and dried under vacuum at 50° C. to give 65 g of Azithromycin monohydrate having water content of 5% (water content measured by the Karl Fischer titration method). This sample of Azithromycin monohydrate crystals has a characteristic solid state (KBr pellet) IR spectrum (FIG. 1) and a characteristic X-ray diffraction pattern (FIG. 2).

출처