Chemical and spectroscopic characterization of pterin-based fluorescent probes

MARIANA VIGNONI; NILUKSHA WALALAWELA; SERGIO BONESI; ALEXANDER GREER; ANDRÉS H. THOMAS

Santiago

Congreso; 25th IAPS Meeting; 2016

Inter-America Photochemistry Society

Pterins are heterocyclic compounds widespread in nature and are derived from 2-aminopteridin-4-(3H)-one (pterin) moiety. These compounds are soluble in water and under UVA radiation (320-400 nm) they can fluoresce, undergo photooxidation to produce different photoproducts, generate reactive oxygen species, such as singlet molecular oxygen (1O2), and photosensitize the oxidation of biomolecules.[1-3] In this work we have synthesized new derivatives where a long carbon chain is attached to different positions of pterin, in a nucleophilic substitution reaction (sn2). A ten carbon chain was attached to position N3 of the heterocyclic ring or to the oxygen of ceto group at C4, leading to the formation of alkylated pterins. Moreover, as N,N-dimethylformamide (DMF) was used as solvent, addition of one molecule of DMF was observed in a condensation reaction to amine group at position C2. These new compounds were characterized by NMR and mass spectrometry, and spectroscopic properties were investigated, such as absorption and emission spectra, and fluorescence lifetime. As they show an improvement in solubility in hydrophobic media comparing to pterin itself, we investigate if the possible use as fluorescence probes, studying their interaction with liposomes.