Synthesis of novel β-lactone inhibitors of fatty acid synthase

Fatty acid synthase (FAS) is necessary for growth and survival of tumor cells and is a promising drug target for oncology. Here, we report oil the syntheses and activity of novel inhibitors of the thioesterase domain of FAS. Using the structure of orlistat as a starting point, which contains a beta-lactone as the central pharmacophore, 28 novel congeners were synthesized and examined. Structural features such as the length of the alpha- and beta-alkyl chains, their chemical composition, and arnino ester substitutions were altered and tile resulting compounds explored for inhibitory activity toward the thioesterase domain of FAS. Nineteen congeners show improved potency for FAS in biochemical assays relative to orlistat. Three of that subset, including the natural product valilactone, also display all increased potency in inducing tumor cell death and improved solubility compared to orlistat. These findings Support the idea that all orlistat congener can be optimized for use in a preclinical drug design and for clinical drug development.