CAS nomenclature

CAS nomenclature is a system of chemical nomenclature used by the Chemical Abstracts Service (CAS). Unlike IUPAC nomenclature, it aims to provide a single, unique name, known as a CAS index name, for each chemical compound (and other well-defined substances) included in Chemical Abstracts. CAS nomenclature is based on the same principles of systematic chemical nomenclature as the IUPAC system, but the resulting names are usually slightly different because of the different finalities of the systems.