Synthesis, spectroscopic characterization and DNA/HSA binding studies of (phenyl/naphthyl)ethenyl-substituted 1,3,4-oxadiazolyl-1,2,4-oxadiazoles

Two new series of conjugated arylethenyl-1,3,4-oxadiazolyl-1,2,4-oxadiazoles were obtained and spectroscopically characterized in terms of UV-Vis absorption, fluorescence and interaction with CT-DNA and Human Serum Albumin (HSA) biomolecules. Phenyl- and 1-naphthyl-bearing examples were analysed, and the spectroscopic properties of its substitution series were compared, showing extensive conjugation in all compounds and absorption differences due to both the aryl-ethenyl subunit and substituted phenyl/phenylene at the 1,2,4-oxadiazole side. Strong binding interactions of the obtained compounds with CT-DNA and moderate HSA-association capability were observed spectroscopically, and further docking studies were performed. Novel 1,3,4-oxadiazolyl-1,2,4-oxadiazole derivatives with promising photophysical and DNA/HSA-binding properties are reported.