Curcumin is the main component of Curcuma longa,a traditional Chinese medicinal herb,with excellent antioxidant.Curcumin is easily decomposed under light and heat.In this study,to find stable antioxidants,6 curcumin analogs(A1-6) were synthesized by coupling the appropriate aromatic aldehyde and cyclohexanon with HCl catalysis,and the free radical（DPPH） scavenging abilities of synthetic curcumin analogs were evaluated.The results showed that the free radical（DPPH） scavenging abilities of curcumin analogs（A2,A3 and A6） were promoted when hydroxyl or methoxyl groups were introduced in the ortho place of phenols,the compound with ortho dihydroxy groups showed the stronges free radical（DPPH） scavenging abilities among curcumin analogs with IC50 of 1.5 μM.
