Undecane n. : A liquid hydrocarbon, C11H24, of the methane series, found in petroleum; -- so called from its containing eleven carbon atoms in the molecule.

Example:
is 5,6-diethyl-3,8-dimethyl-7- propyl Undecane different then 3,8-dimethyl-5,6-diethyl,- 7-propyl Undecane?

Taxonomy
Undecane, free encyclopedia, liquid, search, Physical properties, Identifiers, c1, 3-5-7, 5-7-9, 9-11, 11-10, 10-8, 6-4-2, g/mol, Appearance, Colourless, 26 °C, Hazards.

Defination from the web:
Undecane (also known as hendecane) is a liquid alkane hydrocarbon with the chemical formula CH3(CH2)9CH3. ... Pentane (C5H12) • Hexane (C6H14) • Heptane (C7H16) • Octane (C8H18) • Nonane (C9H20) • Decane (C10H22) • Undecane (C11H24) • Dodecane (C12H26) ...