Sulflower (a portmanteau of sulfur and sunflower) is a stable heterocyclic octacirculene based on thiophene.

With molecular formula (C2S)8 the compound is considered a type of carbon sulfide.

The molecule is flat and together with the 9-membered homolog is at a local strain energy minimum.

[1] Its synthesis (a variation of the Ferrario reaction) is based on deprotonation of a tetrathiophene with lithium diisopropylamide followed by reaction with elemental sulfur to a sulfur-substituted intermediate followed by vacuum pyrolysis.

Because of its planar structure, it is predicted to be able to store many hydrogen molecules between the stacks.