53116-52-2

Upstream product

• 186581-53-3 diazomethane 
• 53116-43-1 (6R)-7t-amino-3,8-dioxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]octane-2ξ-carboxylic acid 4-nitro-benzyl ester; hydrochloride 
• 53116-50-0 p-nitrobenzyl 7-phenylacetamido-3-hydroxy-3-cephalosporin-4-carboxylate 

Downstream Products

• 53116-55-5 (6R)-3-methoxy-8-oxo-7t-(2-thiophen-2-yl-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 53116-67-9 (6R)-3-methoxy-7t-[(R)-2-(2-methoxycarbonyl-1-methyl-vinylamino)-2-phenyl-acetylamino]-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 4-nitro-benzyl ester 
• 53116-59-9 (7β)-3-methoxy-7-[(phenoxyacetyl)amino]-3-cephem-4-carboxylic acid (4-nitrophenyl)methyl ester 
• 51762-07-3 (6R)-3-methoxy-8-oxo-7t-(2-phenyl-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 
• 51803-42-0 (6R)-3-methoxy-8-oxo-7t-(2-phenoxy-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 
• 51762-40-4 (6R)-7t-((R)-2-hydroxy-2-phenyl-acetylamino)-3-methoxy-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 
• 51762-17-5 cefroxadine 
• 53116-61-3 (6R)-7t-((R)-2-hydroxy-2-phenyl-acetylamino)-3-methoxy-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid 4-nitro-benzyl ester 

Relevant academic research and scientific papers

Preparation method of 7-amino-3-methoxy-4-cephalosporanic acid

The invention discloses a preparation method of 7-amino-3-methoxy-4-cephalosporanic acid, and relates to the technical field of synthesis of cephalosporin medical intermediates. CHS is used as a raw material, tetramethylammonium fluoride is used as a methylation reagent, and the 7-amino-3-methoxy-4-cephalosporanic acid is prepared by removing phenylacetyl serving as a 7-amino protecting group and p-nitrobenzyl serving as a protecting group on 4-carboxyl. According to the synthesis method, the price of the initial raw material CHS is lower than that of 3-hydroxycephalosporin, the use of a methylation reagent dimethyl sulfate is avoided, and the whole process is mild and controllable in operation condition and suitable for industrial production.