A Series of Novel HDAC Inhibitors with Anthraquinone as a Cap Group

Although anthraquinone derivatives possess significant antitumor activity, most of them also displayed those side effects like cardiotoxicity, mainly owing to their inhibition of topoisomerase II of DNA repair mechanisms. Our raised design strategy by switching therapeutic target from topoisomerase II to histone deacetylase (HDAC) has been applied to the design of anthraquinone derivatives in current study. Consequently, a series of novel HDAC inhibitors with a tricylic diketone of anthraquinone as a cap group have been synthesized. After screening and evaluation, compounds 4b, 4d, 7b and 7d have displayed the comparable inhibition in enzymatic activity and cell proliferation than that of Vorinostat (SAHA). Notably, compound 4b showed certain selectivity of antiproliferative effects on cancer cell lines over non-cancer cell lines.