Fulvene (pentafulvene) is a hydrocarbon with the formula (CH=CH)2C=CH2. It is a prototype of a cross-conjugated hydrocarbon. Fulvene is rarely encountered, but substituted derivatives (fulvenes) are numerous.
The compounds of every Wikipedia article carrying a Chembox or a Drugbox, refreshed daily, with the values their infoboxes give. The pages need JavaScript; the API does not.