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cyclohexanehexone

n. (context organic compound English) A cyclic oxocarbon derived from cyclohexane

Wikipedia
Cyclohexanehexone

Cyclohexanehexone, also known as hexaketocyclohexane and triquinoyl, is an organic compound with formula CO, the sixfold ketone of cyclohexane. It is an oxide of carbon (an oxocarbon), a hexamer of carbon monoxide.

As of May 2006, this compound had yet to be synthesized in bulk.