A range of bis-triazolylchalcogenium-BTD 3 was synthesized
by a copper-catalyzed azide–alkyne cycloaddition of azido arylchalcogenides 1 and 4,7-diethynylbenzo[c][1,2,5]thiadiazole 2. Eight new compounds were obtained in moderate to good yields
using 1 mol % of copper(II) acetate monohydrate under mild reaction
conditions. In addition, the synthesized bis-triazolylchalcogenium-BTD 3a–3h were investigated regarding their
photophysical, electrochemical, and biomolecule binding properties
in solution. In general, compounds presented strong absorption bands
at the 250–450 nm region and cyan to green emission properties.
The redox process attributed to the chalcogen atom was observed by
electrochemical analysis (CV techniques). In addition, spectroscopic
studies by UV–vis, steady-state emission fluorescence, and
molecular docking calculations evidenced the ability of each derivative
to establish interactions with calf-thymus DNA (CT-DNA) and bovine
serum albumin (BSA). The behavior presented for this new class of
compounds makes them a promising tool as optical sensors for biomolecules.