Cephamycins are a group of

β-lactam antibiotic β-lactam antibiotics (beta-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 ...

s. They are very similar to

cephalosporin The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibioti ...

s, and the cephamycins are sometimes classified as cephalosporins. Like cephalosporins, cephamycins are based upon the

cephem Cephems are a sub-group of β-lactam antibiotics including cephalosporin The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''. T ...

nucleus. Unlike most cephalosporins, cephamycins are a very efficient antibiotic against anaerobic microbes. Cephamycins were originally produced by ''

Streptomyces ''Streptomyces'' is the largest genus of Actinomycetota and the type genus of the family Streptomycetaceae. Over 500 species of ''Streptomyces'' bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, ...

'', but synthetic ones have been produced as well. Cephamycins possess a

methoxy In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula . On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position ...

group at the 7-alpha position. In addition, cephamycins have been shown to be stable against extended-spectrum beta-lactamase (ESBL) producing organisms, although their use in clinical practice is lacking for this indication.

Examples

Cephamycins include: * Cefoxitin * Cefotetan * Cefmetazole

References

Cephalosporin antibiotics {{antibiotic-stub