BP-M345 as a Basis for the Discovery of New Diarylpentanoids with Promising Antimitotic Activity.

Recently, the diarylpentanoid () has been identified as a potent in vitro growth inhibitor of cancer cells, with a GI value between 0.17 and 0.45 µM, showing low toxicity in non-tumor cells. () promotes mitotic arrest by interfering with mitotic spindle assembly, leading to apoptotic cell death. Following on from our previous work, we designed and synthesized a library of () analogs and evaluated the cell growth inhibitory activity of three human cancer cell lines within this library in order to perform structure-activity relationship (SAR) studies and to obtain compounds with improved antimitotic effects. Four compounds (, , , and ) were active, and the growth inhibition effects of compounds , , and were associated with a pronounced arrest in mitosis. These compounds exhibited a similar or even higher mitotic index than (), with compound displaying the highest antimitotic activity, associated with the interference with mitotic spindle dynamics, inducing spindle collapse and, consequently, prolonged mitotic arrest, culminating in massive cancer cell death by apoptosis.