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ChemicalBook CAS DataBase List (6R-trans)-3-(hydroxymethyl)-8-oxo-7-(2-thienylacetamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
5935-65-9

(6R-trans)-3-(hydroxymethyl)-8-oxo-7-(2-thienylacetamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid synthesis

6synthesis methods
-

Yield:5935-65-9 100 g

Reaction Conditions:

with ammonium hydroxide;immobilized cephalosporin C deacetylase in water at 20; pH=7 - 7.5; for 0.05 h;Enzymatic reaction;

Steps:

1 synthesis of 3-Desacetyl Cephalothin

In the flask placed 80 g of 7-ACA with stirring , then 1000 ml of deionized water was added, agitation was carried out and t with 8% aqueous ammonia adjusted pH of 7-ACA to dissolve and controlled temperature to 20 °C. then placed 30 g penicillin g amidase and dropwise added 55 g Methyl 2-thienylacetate mean while with 8% aqueous ammonia controlling the pΗ6.5 to 7.0 until no pH varitaions. The liquid chromatographic test showed that the 7-ACA residue was less than 1.0% in the end of the reaction. The filtrate was collected by filtration, and a small amount of deionized water was used to immobilize the enzyme; the filtrate was added to a stirred flask with a controlled temperature of 20 ° C and 20 g of immobilized cephalosporin C deacetylase was introduced to start the reaction meanwhile with 8% ammonia control pΗ7.0 ~ 7.5 to pH for 3 minutes to not change in the end of the reaction. The filtrate was collected by filtration, the filtrate was stirred to decolorization with 5 g of activated carbon. After 20 minutes, filtration was carried out , then the filtrate was adjusted to pH 2.0 to 2.2 with 10% hydrochloric acid and then cooled to 10 ° C for 1 hour. The product was filtered and washed with a small amount of deionized water and dried in vacuo to give 100 g of product of 3-Desacetyl Cephalothin, Weight Yield 125% (Description: The yield here is the weight yield, can be more than 100%, will not affect the purity).

References:

CN104447800,2016,B Location in patent:Paragraph 0015; 0047-0048

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