4'-Alkoxyl substitution enhancing the anti-mitotic effect of 5-(3',4',5'-substituted)anilino-4-hydroxy-8-nitroquinazolines as a novel class of anti-microtubule agents.

Mitosis inhibitors are powerful anticancer drugs. Based on a novel anti-microtubule agent of 5-(4'-methoxy)anilino-4-hydroxy-8-nitroquinazoline, a series of 5-(3',4',5'-substituted)anilino-4-hydroxy-8- nitroquinazolines were designed and synthesized to investigate the effect of the substitution on the inhibitory activity against mitotic progression of tumor cells. The large alkoxyl substitution on the 4'-position of 5-anilino ring is beneficial for the potency. The 5-(3',4',5'-trimethoxy)anilino-8-nitroquinazoline (1h) displays an overwhelming activity in arresting the cells at the G2/M phase, providing a promising new template for further development of potent microtubule-targeted anti-mitotic drugs.