Tetrahydro-4-Methylene-2-octyl-5-oxo-3-furancarboxylic acid or C75 is an inhibitor of fatty acid synthase. Additionally, C75 increased fatty acid oxidation and ATP levels by increasing carnitine palmitoyltransferase I (CPT I) activity. Unlike the activation produced by C75, the CoA derivative is a potent competitive inhibitor that binds tightly but reversibly to CPT I. C75 exerts antitumor and anti-obese potential. C75 has two enantiomers: (-)-C75 inhibits FAS activity in vitro and has a cytotoxic effect on tumor cell lines, without affecting food consumption, (+)-C75 inhibits CPT1 and its administration produces anorexia, suggesting that central inhibition of CPT1 is essential for the anorectic effect of C75.