Synthesis and evaluation of diverse thio avarol derivatives as potential UVB photoprotective candidates

Semisynthesis of 13 new thio avarol derivatives (4–16) and in vitro evaluation on the photodamage response induced by UVB irradiation are described. Their ability to inhibit NF-κB activation and TNF-α generation in HaCaT cells as well as their antioxidant capacity in human neutrophils has also been studied. Among them we have identified two monophenyl thio avarol derivatives (4–5) lacking cytotoxicity which can be considered promising UVB photoprotective agents through the potent inhibition of NF-κB activation with a mild antioxidant pharmacological profile.