A beta-lactam (β-lactam) ring is a four-membered lactam. A lactam is a cyclic amide, and beta-lactams are named so because the nitrogen atom is attached to the β-carbon atom relative to the carbonyl. The simplest β-lactam possible is 2-azetidinone. β-lactams are significant structural units of medicines as manifested in many β-lactam antibiotics. Up to 1970, most β-lactam research was concerned with the penicillin and cephalosporin groups, but since then, a wide variety of structures have been described.
β-lactam antibiotics are antibiotics that contain a beta-lactam ring in their chemical structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and carbacephems. Most β-lactam antibiotics work by inhibiting cell wall biosynthesis in the bacterial organism and are the most widely used group of antibiotics. Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. The first β-lactam antibiotic discovered, penicillin, was isolated from a strain of Penicillium rubens.
The cephalosporins are a class of β-lactam antibiotics originally derived from the fungus Acremonium, which was previously known as Cephalosporium.
Cephems are a sub-group of β-lactam antibiotics including cephalosporins and cephamycins. It is one of the most common 4-membered ring heterocycle. Produced by actinomycetes, cephamycins were found to display antibacterial activity against a wide range of bacteria, including those resistant to penicillin and cephalosporins. The antimicrobial properties of Cephem include the attachment to certain penicillin-binding proteins that are involved in the production of cell walls of bacteria.
Cefprozil is a second-generation cephalosporin antibiotic. Originally discovered in 1983, and approved in 1992, it was sold under the tradename Cefzil by Bristol Meyers Squibb until 2010 when the brand name version was discontinued. It continues to be available from various companies in its generic form. It is used in the treatment of pharyngitis, tonsillitis, ear infections, acute sinusitis, bacterial exacerbation of chronic bronchitis, and skin and skin structure infections. It is currently available as a tablet and as a liquid suspension.
Cefdinir, sold under the brand name Omnicef among others, is an antibiotic used to treat pneumonia, otitis media, strep throat, and cellulitis. It is a less preferred option for pneumonia, otitis media, and strep throat which may be used in those with a severe allergy to penicillin. It is taken by mouth.
Cefquinome is a fourth-generation cephalosporin with pharmacological and antibacterial properties valuable in the treatment of coliform mastitis and other infections. It is only used in veterinary applications.
Thienamycin is one of the most potent naturally produced antibiotics known thus far, discovered in Streptomyces cattleya in 1976. Thienamycin has excellent activity against both Gram-positive and Gram-negative bacteria and is resistant to bacterial β-lactamase enzymes. Thienamycin is a zwitterion at pH 7.
Cefditoren, also known as cefditoren pivoxil is an antibiotic used to treat infections caused by Gram-positive and Gram-negative bacteria that are resistant to other antibiotics. It is mainly used for treatment of community acquired pneumonia. It is taken by mouth and is in the cephalosporin family of antibiotics, which is part of the broader beta-lactam group of antibiotics.
Latamoxef is an oxacephem antibiotic usually grouped with the cephalosporins. In oxacephems such as latamoxef, the sulfur atom of the cephalosporin core is replaced with an oxygen atom.
Cefonicide is a cephalosporin antibiotic.
Talampicillin is a beta lactam antibiotic from the penicillin family. It is an acid stable prodrug that was administered orally. It is not approved by the FDA for use in the United States. It should be avoided in Liver diseases
Ceftaroline fosamil (INN), brand name Teflaro in the US and Zinforo in Europe, is a cephalosporin antibiotic with anti-MRSA activity. Ceftaroline fosamil is a prodrug of ceftaroline. It is active against methicillin-resistant Staphylococcus aureus (MRSA) and other Gram-positive bacteria. It retains some activity of later-generation cephalosporins having broad-spectrum activity against Gram-negative bacteria, but its effectiveness is relatively much weaker. It is currently being investigated for community-acquired pneumonia and complicated skin and skin structure infection.
Pirandamine (AY-23,713) is a tricyclic derivative which acts as a selective serotonin reuptake inhibitor (SSRI). It was investigated in the 1970s as a potential antidepressant but clinical development was not commenced and it was never marketed. Pirandamine is structurally related to tandamine, which, in contrast, is a selective norepinephrine reuptake inhibitor.
Cephalosporins are a broad class of bactericidal antibiotics that include the β-lactam ring and share a structural similarity and mechanism of action with other β-lactam antibiotics. The cephalosporins have the ability to kill bacteria by inhibiting essential steps in the bacterial cell wall synthesis which in the end results in osmotic lysis and death of the bacterial cell. Cephalosporins are widely used antibiotics because of their clinical efficiency and desirable safety profile.
Teniloxazine, also known as sufoxazine and sulfoxazine, is a drug which is marketed in Japan. Though initially investigated as a neuroprotective and nootropic agent for the treatment of cerebrovascular insufficiency in the 1980s, it was ultimately developed and approved as an antidepressant instead. It acts as a potent norepinephrine reuptake inhibitor, with fair selectivity over the serotonin and dopamine transporters, and also behaves as an antagonist of the 5-HT2A receptor.
Nitrocefin is a chromogenic cephalosporin substrate routinely used to detect the presence of beta-lactamase enzymes produced by various microbes. Beta-lactamase mediated resistance to beta-lactam antibiotics such as penicillin is a widespread mechanism of resistance for a number of bacteria including members of the family Enterobacteriaceae, a major group of enteric Gram-negative bacteria. Other methods for beta-lactamase detection exist including PCR; however, nitrocefin allows for rapid beta-lactamase detection using few materials and inexpensive equipment.
Bottromycin is a macrocyclic peptide with antibiotic activity. It was first discovered in 1957 as a natural product isolated from Streptomyces bottropensis. It has been shown to inhibit methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) among other Gram-positive bacteria and mycoplasma. Bottromycin is structurally distinct from both vancomycin, a glycopeptide antibiotic, and methicillin, a beta-lactam antibiotic.
Ceftolozane/tazobactam, sold under the brand name Zerbaxa, is a fixed-dose combination antibiotic medication used for the treatment of complicated urinary tract infections and complicated intra-abdominal infections in adults. Ceftolozane is a cephalosporin antibiotic, developed for the treatment of infections with gram-negative bacteria that are resistant to conventional antibiotics. It was studied for urinary tract infections, intra-abdominal infections and ventilator-associated bacterial pneumonia.
Cefaparole (cephaparole) is a cephem antibiotic of the cephalosporin subclass that was never marketed.
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