The unbranched isomer is normal or n-heptadecane, CH3(CH2)15CH3. In the IUPAC nomenclature, the name of this compound is simply heptadecane, since the other isomers are viewed and named as alkyl-substituted versions of smaller alkanes.
The most compact and branched isomer would be tetra-tert-butylmethane, but its existence is believed to be impossible due to steric hindrance. Indeed, it is believed to be the smallest "impossible" alkane.[4]
References
↑"heptadecane - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification and Related Records. Retrieved 4 March 2012.