the Cahn-Ingold-Prelog priority rules

The Cahn-Ingold-Prelog (CIP) rules help determine the priority of atoms attached to a chiral center in a molecule, which is essential for defining its 3D structure. Starting with the atoms directly connected to the chiral center, the rules assign higher priority to atoms with higher atomic numbers. If there's a tie, the next set of attached atoms are compared similarly. This process continues until a difference is found. The established priority order helps distinguish the molecule's stereochemistry, which influences its properties and how it interacts biologically.