Antioxidant prenylflavonoids from Artocarpus communis and Artocarpus elasticus

Two new prenylflavonoids, cyclogeracommunin (1) and artoflavone A (2), were isolated from the cortex of roots of Artocarpus communis. Their structures were determined by spectroscopic methods. Compounds 1, 2 and known compounds, artomunoisoxanthone (3), artocommunol CC (4), artochamin D (5), artochamin B (6), and dihydroartomunoxanthone (7), isolated from A. communis, and known compounds, cycloartelastoxanthone (8), artelastoheterol (9), cycloartobiloxanthone (10) and artonol A (11), isolated from Artocarpus elasticus, all showed inhibition of oxidative DNA damage. Compounds 2 and 8-10 significantly showed 1,1-diphenyl-2-picrylhydrazyl (DPPH)-scavenging activity with IC50 values of 24.2 ± 0.8, 18.7 ± 2.2, 42.2 ± 2.8 and 26.8 ± 1.2 μM, respectively, while compounds 1 and 11 significantly displayed inhibitory effects on xanthine oxidase (XO) activity with IC50 values of 73.3 ± 19.1 and 43.3 ± 8.1 μM, respectively. These findings indicate that 1–11 are promising antioxidants.