Diazepam. Molecular model of the drug diazepam (C16.H13.Cl.N2.O). This drug, sold under the brand name Valium, produces a calming effect. It is mainly used to treat anxiety, insomnia, panic attacks and symptoms of acute alcohol withdrawal. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue), oxygen (red) and chlorine (green).