New 1,3,4-Oxadiazinoisoquinoline Methine Cyanine Dyes: Synthesis, Photosensitivity and Antibacterial Activity

Abstract

New heterocyclic ring system including 1,3,4-oxadiazino[6,5-c]isoquinoline was prepared and employed as a precursor for preparation of monomethine and trimethine cyanine dyes. The structure of the new compounds was characterized via elemental analysis and mass, H-1-NMR, and C-13-NMR spectroscopy. The photosensitivity (electronic transitions inside the dye molecule due to photon absorption) of the new methine cyanine dyes was investigated by studying their visible spectra in absolute ethanol and showed its maxima in the visible range of the spectrum with relatively strong absorption bands. The antibacterial activity of the newly synthesized compounds was evaluated against some bacterial strains, resulting in a promising antibacterial efficacy that recommend the tested compounds as new candidates for further pharmaceutical evaluations.