Solvent effects on the formation of Resveratrone

NATHALIE MARTINS-FROMENT; PATRICIA VICENDO; CAROLINA LORENTE; MAIRA GASPAR TOSATO; ANDRÉS H. THOMAS

Villa Carlos Paz , Córdoba, Argentina.

Congreso; XIII Encuentro Latinoamericano de Fotoquímica y Fotobiología (XIII ELAFOT); 2017

ELAFOT

   Cosmeticsskin products and pills containing antioxidants are getting more popular everyday. Theenormous therapeutic potential of RSV in treatments of a wide variety ofdiseases have been postulated and/or demonstrated [1]. However, most of the adverse effects under UV radiation are unknown. Moreover,recent articles mencioned the generation of 4-(6,8-dihydroxynaphthalen-2-yl)but-3-en-2-one,known as resveratrone (RSVT), when trans-resveratrol(t-RSV) and/or cis-resveratrol (c-RSV) areexposed to UV radiation.    Inthis work, the photodegradation of t-RSVand c-RSV in aqueous and ethanol solutionswere investigated employing high pressure liquid chromatography (HPLC) coupledto UV-spectrophotometry and mass spectrometry detectors. The solutions wereirradiated with UVB and UVA for different irradiation times at 298 K.   Severalproducts were identified, both in the presence and the absence of oxygen. Oneof the products obtained was the RSVT (Figure 1). Structure of moleculeconsists of two fused aromatic rings with two hidroxyl groups linked to alinear chain containing a carbonyl group. This novel compound was recentlycharacterized, and it is highly fluorescent with a fluorescence quantumyield  up to 0.5 in some solvents. Thischaracteristic is being analyzed to be used as organic fluorophore inbio-imaging [2][3]. The phenantrene-like photoproducts can acts asphotosensitizer producing singlet oxygen [4] promoting the oxidation of macromolecules.