Orbenine - Cloxacillin

Some related products are quite resistant to penicillinase. For example, methicillin ( Celbenin , Staphcillin ) (6-2, 6 -dimethoxybenzamido-penicillanic acid) which, although having a narrower range and intensity of action than benzylpenicillin, is highly effective in treating patients infected with staphylococci resistant to benzylpenicillin. Unfortunately methicillin is hydrolysed by acid and so must be injected. Two more recently introduced oral penicillins can withstand both acid and penicillinase cloxacillin ( Orbenin ) (R = j2.j2), and oxacillin ( Prostaphlin ) which is cloxacillin minus the chlorine atom. 

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