Synthesis and Antioxidant Properties of Psoralen Derivatives

Abstract

AbstractFive psoralen derivatives were synthesized and the structures of them were characterized by 1H‐NMR, 13C‐NMR, and IR. The antioxidant properties of the compounds were tested by inhibiting the free radical‐initiated DNA oxidation and scavenging the radical reaction. The results showed that the effective stoichiometric factors (n) of the compounds V and IV could reach 2.00 and 2.11 in the system of inhibiting the DNA oxidation reaction initiated by 2,2′‐Azobis(2‐methylpropionamidine) dihydrochloride (AAPH). In the inhibition of ⋅OH‐oxidation of the DNA system, compounds I~V showed antioxidant properties. The thiobarbituric acid absorbance (TBARS) percentages of compounds IV and V were 76.19 % and 78.84 %. Compounds I~V could also inhibit Cu2+/GSH‐oxidation of DNA, and all compounds exhibited good antioxidant properties except compound II (94.00 %). All the five compounds were able to trap diammonium 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonate) salt radical (ABTS+⋅), 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH⋅) and 2,6‐di‐tert‐butyl‐alpha‐(3,5‐di‐tert‐butyl‐4‐oxo‐2,5‐cyclohexadien‐p‐tolylox radical (galvinoxyl⋅). The ability of compounds I~V to scavenge those free radicals can be measured by the k values. The k values ranged from 0.07 to 0.82 in scavenging ABTS+⋅, galvinoxyl, and DPPH radicals, respectively.