Effects of chemical structure, solvent and solution pH on the visible spectra of some new methine cyanine dyes

Some new dimethine and bis-dimethine, cyanine dyes derived from benzo[2,3-b; 2`,3`-b`]bis-pyrazolo[4,5-b]-l,4-(oxa-, thia-, and pyra-)-zine-6,12-dione were synthesized. Effect of chemical structure on the electronic visible absorption spectra of all the synthesized cyanine dyes was investigated in 95% ethanol solution. Effects of solvent and/or solution pH on the electronic visible absorption spectra of some selected synthesized cyanine dyes were also examined in pure solvents having different polarities and/or in aqueous universal buffer solutions, respectively. Structural confirmations were carried out through elemental analysis, mass spectroscopy, IR and 1H NMR spectra

Synthesis, spectral behavior and biological activity of some novel 1,3,4-oxadiazine cyanine dyes

New methine cyanine dyes covering monomethine cyanine dyes and dimethine cyanine dyes derived from benzo[(2,3-b)benzoxazine; (2,3-e)1,3,4-oxadiazine]-5,12-dione were prepared. The electronic visible absorption spectra of all the synthesized cyanine dyes were investigated in 95% ethanol solution. Biological activity for a number of selected compounds was tested and evaluated against various bacterial strains (Bacillus subtilis, Escherichia coli, Pseudomona aeruginosa and Staphylococcus aureus). Structural determination was carried out via elemental analysis, visible, mass, IR and 1H NMR spectroscopic data

Novel styryl and aza-styryl cyanine dyes: Synthesis and spectral sensitization evaluation

Novel styryl cyanine dyes and aza-styryl cyanine dyes having the nucleus of furo[(3,2-d)pyrazole;(3',2'-d)oxazole] iodide salt were prepared. Spectral sensitization evaluation for all the synthesized styryl and aza-styryl cyanine dyes was carried out through investigating their electronic visible absorption spectra in 95% ethanol solution. The dyes were thought to be better spectral sensitizers when they absorb light at longer wavelength bands (bathochromic shifted and/or red shifted dyes). Consequently the spectral sensitization of the dyes decreased when they absorb light at shorter wavelength bands (hypsochromic shifted and/or blue shifted dyes). The results discussed in this study revealed that the spectral sensitization properties of the examined dyes is highly effected by the type of the X substituted in the phenyl ring system for the styryl cyanine dyes and by the type of the phenyl and/or the naphthyl ring system for the aza-styryl cyanine dyes. Structural confirmations were identified by elemental analysis, visible spectra, IR and 1H NMR spectroscopic data