Linezolid antibiotic drug, molecular model. This new drug, marketed as Zyvoxid and Zyvox, is used to treat infections by bacteria, such as MRSA, that are resistant to other antibiotics. It was granted a licence in 2000. It is the first member of the oxazolidinone class of antibiotics, which kill Gram-positive bacteria by preventing them from synthesising proteins. In this molecule, atoms are represented as blobs and are colour- coded: carbon (yellow), hydrogen (white), nitrogen (blue), oxygen (red) and fluorine (green).