IUPAC Nomenclature
The International Union of Pure and Applied Chemistry (IUPAC) nomenclature provides a systematic way to name organic compounds based on their structure. It includes rules for identifying the longest carbon chain, numbering the carbon atoms, and naming substituents. For example, in (S)-1,2-dibromobutane, the '1,2' indicates the positions of the bromine substituents on the butane chain, which is essential for constructing the correct Fischer projection.