14methyl

14methyl is a descriptor used in chemical nomenclature to indicate a methyl substituent attached to the 14th carbon of a parent hydrocarbon skeleton. In standard IUPAC notation, the substituent is written as 14-methyl, with a hyphen separating the locant from the substituent name. The locant designates the carbon atom in the main chain or ring to which the methyl group is bonded.

The identification of the 14th carbon depends on the chosen parent structure, which is typically the longest continuous carbon chain or an appropriate cyclic framework. The numbering is performed to give the lowest possible set of locants for all substituents, so the actual position of a methyl group may vary if a different parent or numbering direction yields a smaller locant set. When more than one methyl group is present, multiple locants are listed in ascending order, and prefixes such as di- or tri- indicate additional methyl substituents (for example, 14,14-dimethyl).

14-methyl appears in the nomenclature of long-chain alkanes, branched alkanes, and more complex natural products where ring systems or multiple substituents constrain numbering. It is not the name of a standalone chemical; rather, it is a way to specify the position of a methyl group within a larger molecule.

See also: IUPAC nomenclature, methyl group, locant, substituent.