Synthesis and Preliminary Evaluation of Several Chalcone Derivatives as Sunscreen Compounds

Four chalcone derivatives containing chloro and methoxy substituents were synthesized and pre-evaluated as broad-spectrum UV protector with intrinsic antioxidant activity. UV absorbance of chalcones 1-4 showed a wide range of UV absorbance values in UVB and UVA regions (max= 310-360 nm) and molar absorptivity values (= 14,000-20,000 Mcm). Chalcones 3 and 4 showed better photostability than chalcones 1 and 2 because the lowering of their absorbance was smaller and slower under UVB irradiation. A combination of the spectra of chalcone derivatives 1-4 indicated that a formulation containing all four will provide a broad-spectrum sunscreen protecting the skin from UVA and UVB.