Synthesis and biological evaluation of pyrano[2,3-f]chromene-4,8-dione derivatives as potential anticancer agents

Based on the hit 5-hydroxy-2-methyl-10-propyl-2,3-dihydro-4 H ,8 H -pyrano[2,3- f ]chromene-4,8-dione( 1 ), a series of pyrano[2,3- f ]chromene-4,8-dione derivatives was designed and synthesized using phloroglucinol as starting material. Meanwhile, a regioselective synthetic route was developed for 5-methoxy-2,3-dihydro-4 H ,8 H -pyrano-[2,3- f ]chromene-4,8-dione products( 11 a― 11 f), and their structures were further confirmed by nuclear Overhauser effect(NOE). The evaluation of anticancer activities of these compounds against four human cancer cell lines, including human glioma cell line (SHG-44), human lung cancer cell line(H1299), breast cancer cell line(MCF7) and human colon carcinoma cell line(HCT-116) in vitro shows that 5-methoxy-2,2-dimethyl-9-chloro-10-trifluormethyl-2,3-dihydro-4 H ,8 H -pyrano-[2,3- f ]chromene-4,8-dione( 11 e) possesses the best anticancer activities with IC 50 values of 6.68, 7.90, 5.16 and 4.82 μmol/L, respectively. Finally, the preliminary structure-activity relationships(SARs) were summarized, which could pave the way for generating more potent anticancer agents with drug-like properties.