Fluorescence Investigations on Interactions between 7,8-benzo-4-azidomethyl Coumarin and Ortho- and Para-phenylenediamines in Binary Solvent Mixtures of THF and Water

Abstract

Fluorescence investigations on interactions between 7,8-benzo-4-azidomethyl coumarin (7BAMC) and quenchers ortho-phenylenediamine (OPD) and para-phenylenediamines (PPD) in binary solvent mixtures (THF + water) have been reported. UV-absorption study indicated a weak hydrophobic interaction between 7BAMC and the para isomer. NMR spectral studies indicated the presence of an interaction between 7BAMC and PPD. Magnitudes of the parameters associated with FRET, showed the presence of interactions between 7BAMC and PPD quencher is more predominant than OPD. Fluorescence quenching studies reveal the role of static and dynamic quenching pathways, depending upon Stern-Volmer constant, dielectric constant and dominant non-radiative processes. Binding equilibria analysis indicates a strong interaction between 7BAMC and PPD than OPD and formation of H-bonding. Based on the magnitudes of free energy, enthalpy change and entropy, bimolecular interaction process may be considered as spontaneous and hydrophobic.

Investigation of the Fluorescence Turn-off Mechanism, Genome, Molecular Docking In Silico and In Vitro Studies of 2-Acetyl-3H-benzo[f]chromen-3-one

“…Table presents the values of K SV 0 , D , and distance parameter ( R ′) evaluated from eq . The obtained results were compared and found to be consistent with the literature. , However, according to Zeng and Joshi , et al, quenching reactions are said to be diffusion-limited only when R ′ is larger than R , and k q > 4π N ′ R ′ D . , From Table , it is confirmed that R ′ > R and k q > 4π N ′ R ′ D , in all of the ACN + DXN solvent mixtures. Hence, reactions are said to be diffusion-limited.…”

“…The obtained results were compared and found to be consistent with the literature. 50 , 51 However, according to Zeng and Joshi 45 , 46 et al, quenching reactions are said to be diffusion-limited only when R ′ is larger than R ( 52 , 53 ) and k q > 4π N ′ R ′ D . 54 , 55 From Table 3 , it is confirmed that R ′ > R and k q > 4π N ′ R ′ D 56 , 57 in all of the ACN + DXN solvent mixtures.…”