The fatty-acid synthase (FAS) is the key enzyme that executes de novo fatty acid synthesis and is overexpressed in some human cancer tissues. C75 is a synthetic FAS inhibitor, which produces the death of cancer cells. In this work, we synthesized three derivatives of C75, two homologs with 1 and 2 carbons more in the beta position of the lactone and the other one with a change in the elongation of the aliphatic chain in gamma position from 8 to 15 carbons. The results from FAS inhibition and cytotoxic properties suggest that the performed changes in the derivatives decrease their activity.