A novel heterocyclic thiosemicarbazone: synthesis, characterization and preliminary sensing studies for ions

Over the past decades, the interest in the fast and sensitive recognition and detection of molecules and ions with biological and/or environmental relevance has increased. Therefore, the search of new molecules capable of coordinating these analytes is an important topic of investigation, especially those with an optical response (via colour or fluorescence changes). Thiosemicarbazones are versatile organic compounds due to their wide range of biological activities and interesting optical, electronic and redox properties. Also, they possess various binding sites, whose complexing ability can be tuned by the introduction of substituents of different electronic character.

Having this in mind, we report the synthesis of a new thiosemicarbazone derivative functionalized with a nitrogen heterocyclic moiety. The new compound was characterized by ¹H and ¹³C NMR, UV-Vis absorption and fluorescence spectroscopies. Moreover, a preliminary chemosensory study was undertaken in acetonitrile solutions in the presence of relevant ions with biological, medicinal and environmental relevance showing that this receptor has potential application as a fluorimetric chemosensor.