[A new aurone with anti-inflammatory activity from Cleistocalyx operculatus flower buds].

A new compound(Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone was isolated from Cleistocalyx operculatus flower buds. Its structure was identified by spectroscopic data including MS, ¹H-NMR, ¹³C-NMR HSQC and HMBC. A known compound, 2',4'-dihydroxy-6'-methoxy-3'5'-dimethylchalcone (DMC), was also isolated and identified,and used as material to synthesize (Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone.Anti-inflammatory activities of the two compounds were tested in vitro. The results showed that (Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone possesses much stronger PGE₂ inhibitory activity (IC₅₀ 6.12 nmol·L⁻¹) than the positive control ibuprofen （68.66 nmol·L⁻¹）.