Synthesis, Anti-cancer Activity and Mechanism Study of 6-Mercapto-purine Derivatives

6-mercaptopurine (6-MP) is the first active metabolite inhibitor shown to suppress cancer cells. The aim of this study is to investigate the bioactivity of 6-MP derivatives and discover new anti-cancer agents. Four 6-mercaptopurine (6-MP) derivatives were synthesized and their anti-cancer activities were analyzed. All of the compounds showed anti-proliferative effects against HepG2 and A2780 cancer cells. Among the synthesized derivatives, 6-((naphthalen-2-ylmethyl)thio)-9H-purine (NMSP) which possessing a β-naphthalene, showed better anti-cancer activity than other compounds, with an IC50 value 6.09μg/mL. NMSP could induce S phase cell cycle arrest and apoptosis in HepG2 cells. Western blot analysis indicated that NMSP induced apoptosis is mitochondria-dependent. The novel 6-MP derivative discovered in this study is a promising drug candidate to be used as an anti-cancer agent.