Tuning the Computational Evaluation of Spectroscopic, ELF, LOL, NCI analysis and Molecular Docking of Novel Anti COVID-19 Molecule 4-Dimethylamino Pyridinium 3, 5-Dichlorosalicylate

Experimental study and quantum chemical calculation of free radical reactions in ciprofloxacin degradation during the UV/chlorine oxidation process

“…FMO theory was used to investigate the reaction features of ciprofloxacin, which assumes that the HOMO and LUMO molecular orbitals have critical roles in the electrophilic, nucleophilic, and radical reactions. 55,56 As seen in Fig. 4, the orbital distribution of ciprofloxacin suggests that the HOMO orbital is mainly concentrated around the piperazine ring.…”

“…Both the ELF and LOL reflect energy density functions in different forms, giving a similar analysis. 56 Fig. S2† shows that the domains around hydrogen with high values of ELF/LOL imply the existence of highly localized bonding and non-bonding electrons.…”

“…The ELF (electron localization function) and LOL (localized orbital locator) were studied to indicate how much of the domain's electrons are restricted to this area. 55,56,68 A LOL with a high value (>0.5) indicates the place where localized electrons dominate the electron density. Both the ELF and LOL reflect energy density functions in different forms, giving a similar analysis.…”

Synthesis, spectroscopic, topological, hirshfeld surface analysis, and anti-covid-19 molecular docking investigation of isopropyl 1-benzoyl-4-(benzoyloxy)-2,6-diphenyl-1,2,5,6-tetrahydropyridine-3-carboxylate

“…The red colour legend indicates the upper limit values close to 1; white indicates values that exceed the upper limit; black depicts values below the lower limit; and blue indicates values below 0.5. Values of ELF close to unity indicates great localization of electron suggesting a nonbonding electron pair, covalent bond or inner shells of the atom involved while values <0.5 depict electron delocalization 90 , 91 . The LOL also explains the localization of orbitals, where small LOL value essentially appears at the boundary region and large values appear at the inner region of the localized orbitals.…”

“…The colour-shaded ELF and LOL maps of IDPC are reported in Figure 5 (a) and (b), respectively. The red region around the hydrogen atoms in the ELF and LOL maps indicates high electron localization due to covalent bond or lone-pair of electrons while the light blue and deep blue colour in the inner regions of the nitrogen (N43) and phenyl carbon atoms signifies remarkable delocalization of electron cloud [ 90 ]. Additional information about the localization of atomic orbitals was obtained for the hydrogen and carbon atoms in the LOL topological analysis.…”