Abstract:
The present invention relates to a crystalline form of an intermediate for cefoperazone of formula (1 ) and to a process for the preparation thereof by enzymatic condensation of a 3'-thiosubstituted β-lactam nucleus with a phenylglycine derivative.
Abstract:
The invention relates to a process for preparing cephradine, said process comprising converting D-dihydrophenylglycine (DHPG) into an activated form (DHPGa); and reacting 7-aminodesacetoxy-cephalosporanic acid (7-ADCA) with D- dihydrophenylglycine in activated form (DHPGa) in the presence of an enzyme in an aqueous reaction mixture to form cephradine characterized in that at least step (a) and step (b) of the process are carried out under anaerobic conditions.
Abstract:
An enzymatic process under kinetical control for preparing β-lactams, by coupling the 7-amino group of a cephalosporin nucleus with the carboxylic function of an acetic acid derivative consisting of a residue with π-electrons, a short spacer and a carboxylic function activated as hydroxyethylester. The process comprises using a penicillin amidase or α-amino acid esterase as free enzyme or in any suitable immobilised form; applying at least 100 mmol/l cephalosporin nucleus, applying the acetic acid derivative activated as hydroxyethylester in a 1 - 3 fold molar ratio, and adjusting the pH to 6.0 - 8.0 and the temperature to 0 - 30°C.
Abstract:
Process for the preparation of a beta -lactam antibiotic in which a beta -lactam nucleus is subjected to an enzymatic acylation reaction with the aid of an acylation agent at a molar ratio of acylation agent/ beta -lactam nucleus of less than 2.5, with the acylation agent and/or the beta -lactam nucleus being supersaturated in the reaction mixture during at least part of the acylation reaction. In the process, a concentrated slurry or solution, for instance, of the beta -lactam nucleus and/or the acylation agent with a different pH or a higher temperature than the pH or temperature at which the acylation reaction is carried out is added to the reaction mixture during the acylation reaction. Both the beta -lactam nucleus and the acylation agent may be supersaturated in the reaction mixture.
Abstract:
Synthesis of semi-synthetic monobactamic or beta -lactamic antibiotics by using derivatives stabilized by various methods of penicillin G acylase from various microbial sources according to a thermodynamically controlled strategy in monophase water/cosolvent organic apolar systems, wherein the concentration of the cosolvent varies between 30 % and 90 %, the temperature between -10 DEG C and 50 DEG C, the pH between 4.5 and 8.5, with concentrations of the antibiotic nucleus between 0.5 and 875 mM and acyl donor between 0.2 mM and 1 M, with a relationship antibiotic ring/activated or free acyl donor, using a buffer between 0 and 1 M. Application to the pharmaceutical industry.
Abstract:
The present invention relates to a crystalline form of an intermediate for cefoperazone of formula (1 ) and to a process for the preparation thereof by enzymatic condensation of a 3'-thiosubstituted beta-lactam nucleus with a phenylglycine derivative.
Abstract:
The invention relates to a process for preparing cephradine, said process comprising converting D-dihydrophenylglycine (DHPG) into an activated form (DHPGa); and reacting 7-aminodesacetoxy-cephalosporanic acid (7-ADCA) with D- dihydrophenylglycine in activated form (DHPGa) in the presence of an enzyme in an aqueous reaction mixture to form cephradine characterized in that at least step (a) and step (b) of the process are carried out under anaerobic conditions.
Abstract:
A process for preparing the 7-(1-H-tetrazol-1-yl) acetamide-3-(2-methyl-1,3,4-thiadiazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid or cefazolin, comprising catalysing the acylation of the amino β-lactam, the 7-amino-3-[5methyl-1,3,4-thiadiazol-2-yl)thiomethyl]-3-cephem-4-carboxylic acid, of the formula with an activated acylating agent derived from acetic acid in the presence of a biocatalyst comprising penicillin amidase, and a product of the formula I obtainable by the foregoing process according to claims.
Abstract:
An enzymatic process under thermodynamical control for preparing b-lactams, by coupling the 7-amino group of a cephalosporin nucleus with the carboxylic function of an acetic acid derivative consisting of a residue with p-electrons, a short spacer and a carboxylic function. The process comprises using a penicillin amidase as free enzyme or in any suitable immobilised form; applying no or maximum 10 % organic solvent, applying at least 100 mmol/l cephalosporin nucleus, applying the free acetic acid derivative in a 3 - 5 fold molar ratio, reducing the pH by acid according the reaction progress from initially pH 7.5 - 6.25 to pH 6.25 - 5.0 and adjusting 10 - 40°C.
Abstract:
The present invention describes a process wherein Acremonium is used as a suitable and convenient organism for the production of N-acylated cephalosporin derivatives. In the process of the invention, a recombinant, acyltransferase-expressing Acremonium strain is cultured in the presence of a suitable acyl side chain precursor. Optionally, the acyltransferase-expressing Acremonium strain further does not express hydroxylase and/or acetyltransferase activity. The N-acylated cephalosporin derivative is recovered without contaminating α-aminoadipyl cephalosporin compounds. The thus recovered compound subsequently may be deacylated via chemical or enzymatical means.