تفاعل #5615

معادلة التفاعل

ethyl acetate

7β-formamido-3-[N,N-dimethyl-N-{(5-hydroxy-4-oxo-1,4-dihydropyridin-2-yl)methyl}ammonio]methyl-3-cephem-4-carboxylate

hydrochloric acid

→

7β-amino-3-[N,N-dimethyl-N-{(5-hydroxy-4-oxo-1,4-dihydropyridin-2-yl)methyl}ammonio]methyl-3-cephem-4carboxylate dihydrochloride

المذيبات

formic acid

ظروف التفاعل

المعالجة

1. 1
   أخرىthe supernatant was decanted
2. 2
   workup.DISSOLUTIONThe residual oil was dissolved in methanol (50 ml)
3. 3
   workup.ADDITIONthe solution was poured into ethyl acetate (600 ml)
4. 4
   أخرىThe resulting precipitates
5. 5
   ترشيحwere collected by filtration
6. 6
   غسيلwashed with ethyl acetate and diisopropyl ether
7. 7
   أخرىdried in vacuo
8. 8
   workup.DISSOLUTIONThe powder was dissolved in cold water (28 ml)
9. 9
   أخرىchromatographed on Diaion HP-20 (28 ml) at 5° C.
10. 10
    غسيلthe elution
11. 11
    workup.ADDITIONTo the eluate (30 ml) was added dropwise cold isopropyl alcohol (19 ml)
12. 12
    درجة الحرارةunder cooling
13. 13
    workup.STIRRINGthe mixture was stirred at 5° C. for an hour
14. 14
    ترشيحThe resultant crystal was collected by filtration
15. 15
    غسيلwashed with a cooled mixture of isopropyl alcohol and water (10:1) and cold isopropyl alcohol
16. 16
    أخرىdried in vacuo

الإجراء التجريبي

To a cooled solution of 7β-formamido-3-[N,N-dimethyl-N-{(5-hydroxy-4-oxo-1,4-dihydropyridin-2-yl)methyl}ammonio]methyl-3-cephem-4-carboxylate (4.084 g) in formic acid (8.1 ml) was added dropwise conc. hydrochloric acid (2.5 ml). The mixture was warmed to room temperature and stirred for 2.5 hours. The mixture was added dropwise to ethyl acetate (400 ml) and the supernatant was decanted. The residual oil was dissolved in methanol (50 ml) and the solution was poured into ethyl acetate (600 ml). The resulting precipitates were collected by filtration, washed with ethyl acetate and diisopropyl ether and dried in vacuo. The powder was dissolved in cold water (28 ml) and chromatographed on Diaion HP-20 (28 ml) at 5° C., and the elution was carried out with water. To the eluate (30 ml) was added dropwise cold isopropyl alcohol (19 ml) under cooling and the mixture was stirred at 5° C. for an hour. The resultant crystal was collected by filtration washed with a cooled mixture of isopropyl alcohol and water (10:1) and cold isopropyl alcohol, and dried in vacuo to give 7β-amino-3-[N,N-dimethyl-N-{(5-hydroxy-4-oxo-1,4-dihydropyridin-2-yl)methyl}ammonio]methyl-3-cephem-4carboxylate dihydrochloride (728 mg).

المصدر