Non-cytotoxic dimedone derivatives: structure, antiradical and UV protective studies.

Dimedone derivatives (L1-L4) with methyl substitution at the ortho, para and meta positions were synthesized and their anti-radical, photoreactive and photostability activities were evaluated. All compounds are characterized by spectroscopic techniques and by single crystal X ray diffraction. UV exposure experiments on pBR322 showed inhibition of plasmid DNA fragmentation by UV radiation in a dose dependent manner. Radical scavenging assays and ESR spectra indicate that these compounds possess antiradical activities and do not photodegrade to form other side products as confirmed by chromatographic analysis. They are non-cytotoxic towards human keratinocyte HaCaT cell line indicates their potentiality in sunscreens.