Complex sentence: A series of synthetic analogues were prepared to remove the chirality and optimize biological activity which led to the potent anti-tumor agent plinabulin which is active in multidrug-resistant (MDR) tumor cell lines.
Split into simpler sentences: A series of synthetic analogues were prepared to remove the chirality and optimize biological activity. These studies led to the potent anti-tumor agent plinabulin, which is active in multidrug-resistant (MDR) tumor cell lines.