• carbonyl
  • The second is called "Cohen's parameter", c, and is the distance between the carbon atom of the carboxylate and the oxygen atom of the β-lactam carbonyl. (wikipedia.org)
  • The imine can be replaced by adding olefin to produce a cyclobutanone, carbonyl to produce a β-lactone, or carbodiimides to produce 4-imino β-lactams. (wikipedia.org)
  • enzyme
  • Bacteria often develop resistance to β-lactam antibiotics by synthesizing a β-lactamase, an enzyme that attacks the β-lactam ring. (wikipedia.org)
  • In enzymology, a (carboxyethyl)arginine beta-lactam-synthase (EC 6.3.3.4) is an enzyme that catalyzes the chemical reaction ATP + L-N2-(2-carboxyethyl)arginine ⇌ {\displaystyle \rightleftharpoons } AMP + diphosphate + deoxyamidinoproclavaminate Thus, the two substrates of this enzyme are ATP and L-N2-(2-carboxyethyl)arginine, whereas its 3 products are AMP, diphosphate, and deoxyamidinoproclavaminate. (wikipedia.org)
  • In enzymology, a 2-aminohexano-6-lactam racemase (EC 5.1.1.15) is an enzyme that catalyzes the chemical reaction L-2-aminohexano-6-lactam ⇌ {\displaystyle \rightleftharpoons } D-2-aminohexano-6-lactam Hence, this enzyme has one substrate, L-2-aminohexano-6-lactam, and one product, D-2-aminohexano-6-lactam. (wikipedia.org)
  • The systematic name of this enzyme class is 2-aminohexano-6-lactam racemase. (wikipedia.org)
  • compounds
  • A process for preparing N-substituted lactams, as well as pharmaceutical compositions containing these compounds as active component. (google.com)
  • The present invention relates to a process for the preparation of lactams from dinitriles.It consists more precisely of a process for the preparation of lactam, linking two stages in series, one of hemihydrogenation of dinitrile to aminonitrile, the other of cyclizing hydrolysis of the aminonitrile after only one simple purification operation.Aliphatic lactams, such as especially epsilon-caprolactam, are base compounds for the preparation of polyamides (polyamide 6 from caprolactam). (patentgenius.com)
  • Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. (wikipedia.org)
  • efficacy
  • 6 Of the three pharmacodynamic parameters described with antimicrobials, optimal efficacy with beta-lactams is achieved when free drug concentrations stay above the minimum inhibitory concentration (MIC) for an extended duration of the recommended dosing interval ( FIGURE 1 ). (uspharmacist.com)
  • chiral
  • Subsequent ring closure leads to the formation of the β-lactam and the regeneration of the chiral nucleophilic organocatalyst. (wikipedia.org)
  • precursors
  • Inhibition of cross-linkage by β-lactams causes a build-up of peptidoglycan precursors, which triggers the digestion of existing peptidoglycan by autolytic hydrolases without the production of new peptidoglycan. (wikipedia.org)
  • Clinical
  • NYSE MKT: SYN), a clinical stage company focused on developing therapeutics to protect the gut microbiome while targeting pathogen specific diseases, announced positive topline results from the first Phase 2a study of SYN-004, the Company's candidate designed to protect the gut microbiome from the unintended effects of certain commonly used intravenous (IV) beta-lactam antibiotics for the prevention C. (thefreedictionary.com)
  • This is a list of common β-lactam antibiotics-both administered drugs and those not in clinical use-organized by structural class. (wikipedia.org)
  • extensively
  • Other beta-lactams have not been studied as extensively, since achievement of pharmacodynamic goals is likely ideal even with standard dosing. (uspharmacist.com)
  • catalyst
  • and hydrolyzing the distilled aminonitrile with water in the vapor phase in the presence or the absence of a catalyst to form said lactam. (patentgenius.com)
  • mainly
  • At first, β-lactam antibiotics were mainly active only against Gram-positive bacteria, yet the recent development of broad-spectrum β-lactam antibiotics active against various Gram-negative organisms has increased their usefulness. (wikipedia.org)
  • Ketenes with strong electron-donating substituents mainly produce cis β-lactams, while ketenes with strong electron-withdrawing substituents generally produce trans β-lactams. (wikipedia.org)
  • attacks
  • The tertiary amine contained within the quinuclidine can act as a nucleophile that attacks the most electrophilic carbon of the ketene to promote the formation of β-lactams. (wikipedia.org)
  • commonly
  • Sulfuric acid is the most commonly used acid for commercial lactam production due to its formation of an ammonium sulfate by-product when neutralized with ammonia. (wikipedia.org)
  • reactions
  • Cation-π Control of Regiochemistry of Intramolecular Schmidt Reactions en Route to Bridged Bicyclic Lactams" (Communication). (wikipedia.org)
  • organisms
  • The broad-spectrum beta-lactams cefepime, meropenem, and piperacillin-tazobactam are the agents most studied for this dosing strategy, as they have reliable activity against most gram-negative organisms, including Pseudomonas aeruginosa. (uspharmacist.com)
  • drugs
  • Because of the popularity of beta-lactam drugs, certain bacteria have been able to develop counter-measures to traditional drug therapies. (princeton.edu)
  • structure
  • citation needed] Antiproliferative agents that target tubulin with β-lactams in their structure have also been reported. (wikipedia.org)
  • high
  • 11-13 Because most beta-lactams have high renal excretion and renal dysfunction prolongs drug elimination, prolonging drug infusion is unlikely to improve PTA in patients receiving these agents. (uspharmacist.com)