Mesalamine. Molecular model of the drug mesalamine (C7.H7.N.O3). This anti-inflammatory drug, sold under the brand name Asacol, is used to treat inflammatory bowel disease, including ulcerative colitis, inflamed anus or rectum, and to maintain remission in Crohn's disease. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue) and oxygen (red).