Reaktion #310804

Reaktionsgleichung

7β-{α-ethoxyimino-[2-(chloroacetamido)thiazol-4-yl]acetamido}-3-(1-methyl-1H-tetrazol-5-ylthiomethyl)-3-cephem-4-carboxylic acid benzhydryl ester

thiourea

→

7β-[α-ethoxyimino-(2-aminothiazol-4-yl)acetamido]-3-(1-methyl-1H-tetrazol-5-ylthiomethyl)3-cephem-4-carboxylic acid benzhydryl ester

Ausbeute 52.9%

Lösungsmittel

tetrahydrofuran

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenconcentrated
2. 2
   workup.DISSOLUTIONThe residue is dissolved in a mixture of ethyl acetate and tetrahydrofuran
3. 3
   Waschenthe solution was washed with aq. sodium bicarbonate solution
4. 4
   Trocknenby drying over anhydrous magnesium sulfate
5. 5
   workup.DISTILLATIONThe dried solution is subjected to distillation of the solvent
6. 6
   Sonstigeto give powder which
7. 7
   Waschenis washed with chloroform and ether
8. 8
   Sonstigedried

Vorschrift

To a solution of 2.2 g of 7β-{α-ethoxyimino-[2-(chloroacetamido)thiazol-4-yl]acetamido}-3-(1-methyl-1H-tetrazol-5-ylthiomethyl)-3-cephem-4-carboxylic acid benzhydryl ester in 20 ml of tetrahydrofuran is added a solution of 550 mg of thiourea in 20 ml of ethanol, followed by addition of 50 ml of triethylbenzylammonium bromide. The mixture is stirred for 20 hours at room temperature and concentrated. The residue is dissolved in a mixture of ethyl acetate and tetrahydrofuran and the solution was washed with aq. sodium bicarbonate solution and then water, followed by drying over anhydrous magnesium sulfate. The dried solution is subjected to distillation of the solvent to give powder which is washed with chloroform and ether and dried. The procedure yields 1.047 g of 7β-[α-ethoxyimino-(2-aminothiazol-4-yl)acetamido]-3-(1-methyl-1H-tetrazol-5-ylthiomethyl)3-cephem-4-carboxylic acid benzhydryl ester. Yield 52.9%.

Quelle