US chemists have found a way to regioselectively replace one of the carbon atoms in a benzene ring with a nitrogen atom, reports Science.

Medicinal chemistry uses molecules containing nitrogen atoms, such as pyridine. The search for new drugs therefore often involves a ‘nitrogen scan’, in which a nitrogen atom is placed at various points in the target molecule to see what effect it has on the drug target. Normally, this is a tedious process that involves redesigning the molecule multiple times to position the nitrogen atom elsewhere. Tyler Pearson, Mark Levin and colleagues at the University of Chicago have now found a simple solution. They developed a protocol that allows you to replace a carbon atom in a benzene ring with a nitrogen atom.