Heptane
Heptane is a chain of 7 carbons, with n-heptane being the straight chain of 7 carbons (the "n" in n-heptane stands for "normal" which means a straight carbon chain.) Heptane is available as pure n-heptane but also as mixed isomers (branched chains of 7 carbons).

Market Dynamics:
N-Heptane is used in laboratories as a non-polar solvent​. Branched/mixed isomers of heptane is used in paints and coatings. Even though heptane is a hydrocarbon, it is not added to gasoline mixtures because it burns explosively, causing engine knocking​.

Up Stream Materials/Building Blocks:
​Crude oil 

Heptane (n-heptane), Straight carbon Chain

Coproducts: isomers/branched heptane:
  2-Methylhexane (isoheptane)
  3-Methylhexane
  2,2-Dimethylpentane (neoheptane)
  2,3-Dimethylpentane
  2,4-Dimethylpentane
  3,3-Dimethylpentane,
  3-Ethylpentane,
  2,2,3-Trimethylbutane,(aka pentamethylethane and triptane)

Down Stream Materials Consuming Heptane:

Paints

Coatings

Camp stove fuel