An array of bengamide E analogues modified at the terminal olefinic position: synthesis and antitumor properties.

Based on our previously described synthetic strategy for bengamide E, a natural product of marine origin with antitumor activity, a small library of analogues modified at the terminal olefinic position was generated with the objective of investigating the effect of structural modifications on antitumor properties. Biological evaluation of these analogues, consisting of IC50 determinations against various tumor cell lines, revealed important aspects with respect to the structural requirements of this olefinic position for activity. Interestingly, the analogue possessing a cyclopentyl group displayed greater potency than the parent bengamide E, representing a key finding upon which to base further investigations into the design of new analogues with promising biological activities.