Synthesis and molecular modelling of new donor-π-acceptor benzothiazole-carbazole-pyridine-based fluorescent chromophore

The targeted benzothiazole-carbazole-pyridine dye (ThCzPy) was synthesized using a synthetic approach completed by the condensation of 6-(benzothiazol-2-yl)-3-formyl-9-hexyl-9H-carbazole (4) with 4-aminopyridine (5). The absorption and emission spectra of the chromophore ThCzPy, in DMSO, displayed good Stokes’ shift ($\Delta \overline{\nu }$ = 4653 cm⁻¹). The DFT configuration of the frontier molecular orbits in gas and solvated ground state (S_o) were compared to the solvated excited state (S₁). Furthermore, the new chromophore’s antimicrobial efficacy was evaluated as minimum inhibitory concentration (MIC) against a panel of Gram’s positive, negative, and fungi using ampicillin and fluconazole as reference drugs, where it exhibited comparable activity. The SwissADME study revealed that ThCzPy has a bioavailability score 0.55 and meets Lipinski’s criteria for drug similarity.