ABSTRACT
The use of sunscreen has become an indispensable daily routine since UV radiation is a critical environmental stress factors for human skin. This study focused on the design, synthesis, thermal/chemical stability and efficacy/safety evaluations of a new heterocyclic derivative, namely LQFM184, as a photoprotective agent. The compound showed stability when submitted under oxidative and high-temperature conditions. It also revealed an absorption at 260-340 nm (UVA/UVB), with a main band at 298 nm and a shoulder close to 334 nm. LQFM184 showed capacity to interact with other existing UV filters, promoting an increase in the sun protection factor. In relation to acute toxicity, its estimated LD50 was >300-2000 mg kg-1 , probably with a low potential of inducing acute oral systemic toxicity hazard. In addition, our data showed that this compound did not have eye irritation, skin sensitization or phototoxicity potentials. Taken together, these findings make LQFM184 a promising ingredient to be used, alone or in association with other UV filters, in cosmetic products such as sunscreens with a broad spectrum of protection.
Subject(s)
Sunscreening Agents/chemistry , Ultraviolet Rays , 3T3 Cells , Animals , Cattle , Cosmetics/chemistry , Humans , Mice , Mice, Inbred BALB C , Spectrum Analysis/methods , Sunscreening Agents/pharmacology , Sunscreening Agents/toxicity , U937 CellsABSTRACT
The interaction of rhodium dimers, including the carboxylates (acetate, propionate, butyrate, trifluoroacetate, citrate and gluconate), amidates (acetamidate and trifluoroacetamidate) and carboxamidate (Doyle catalyst S) with DNA was investigated by electrochemical methods. Differential pulse voltammetry measurements showed, in agreement to literature data, that most of rhodium carboxylates have a higher affinity for adenine than guanine residues. Some differences of reactivity may be correlated with the compound structures and these were helpful in understanding the influence of equatorial ligands on axial coordination mechanisms. The preliminary results might be extended for further studies on quantitative structure activity relationship approaches, highlighting electrochemical methods as a tool for this purpose.
