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US 5,608,055 AGranted
Beta lactam production
AssigneeBiochemie Gesellschaft m.b.H.
InventorsJose Diago, Johannes Ludescher
Life of this patent
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Abstract
A new process is described for the production of 7-alpha-aminoacyl-cephalosporin free from halogen-containing solvents by acylating 7-amino-ceph-3-em-4-carboxylic acid or a derivative thereof in a halogen-free solvent.
Claims17
In a process for the production of a 7-alpha-aminoacyl- cephem other than a 7-alpha-aminoacyl-desacetoxy-cephalosporin which comprises the steps of:
- i) producing a mixed carboxylic acid anhydride by reacting an N-substituted vinyl alpha-amino acid with an acylating agent;
- and
- ii) reacting the mixed carboxylic acid anhydride with a 7-amino-ceph-3-em-4-carboxylic acid or derivative thereof,
- the improvement which comprises carrying out step i) in a solvent which does not contain a halogen atom and which is water-immiscible or sparingly soluble in water and is selected from ketones, esters, aromatic hydrocarbons, and mixtures thereof;
- and carrying out step ii) with a non-silylated 7-amino-ceph-3-em-4-carboxylic acid or derivative thereof in a solvent which does not contain a halogen atom and is selected from ketones, esters, aromatic hydrocarbons, alkanols, and mixtures thereof.
2 more elements
A process according to claim 13 wherein the co-solvent is selected from formamide, acetamide, N,N-dimethyl formamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidine, tetramethylurea and isopropanol.
Dependencies are inferred from the claim text.