These area group of semisynthetic antibiotics derived from
‘cephalosporin-C’ obtained from a fungus Cephalosporium.
They are chemically related to penicillins; the nucleus
consists of a β-lactam ring fused to a dihydrothiazine ring,
(7-aminocephalosporanic acid).
By addition of different side chains at position 7 of β-lactam
ring (altering spectrum of activity) and at position 3 of
dihydrothiazine ring (affecting pharmacokinetics), a large
number of semisynthetic compounds have been produced.
3.
divided into4 generations, and now some lately added
members have been designated ‘5 th generation’.
This newgroup are distinguished by their ability to kill MRSA penicillin
resistance by producing altered PBPs
Ceftaroline fosamil
It is a prodrug which after i.v. infusion is rapidly converted by
phosphatases to the active ceftaroline.
that is cidal to many gram +ive and gram –ive bacteria including MRSA,
penicillin resistant Strep. Pneumoniae and Enterococcus faecalis, etc.
Ceftaroline owes its activity to its ability to bind altered PBPs expressed in
these bacteria.
It has high affinity for PBP2a (in MRSA), for PBP2b and PBP2x (in penicillin
resistant Strep. pneumoniae).
