Synthesis, Crystal Structural Investigations, and DFT Calculations of Novel Thiosemicarbazones

Abstract

(7)˝, β = 92.413(6)˝, and γ = 90.654(7)˝. DFT B3LYP/6-31(G) geometry optimized molecular orbital calculations were also performed and frontier molecular orbitals of each compound are displayed. The correlations between the calculated molecular orbital energies (eV) for the surfaces of the frontier molecular orbitals to the electronic excitation transitions from the absorption spectra of each compound have been proposed. Additionally, similar correlations observed among three closely related compounds, (4), 2-[1-(2-hydroxy-4-methoxyphenyl)ethylidene]-N-methyl-hydrazinecarbothioamide, (5), 2-[1-(2-hydroxy-6-methoxyphenyl)ethylidene]-N-methyl-hydrazinecarbothioamide acetonitrile monosolvate and (6), 2-[1-(2-hydroxy-6-methoxyphenyl)ethylidene]-N-ethyl-hydrazinecarbothioamide, examining structural differences from the substitution of the methoxy group from the phenyl ring (4, 5, or 6 position) and the substitution of the terminal amine (methyl or ethyl) to their frontier molecular orbital surfaces and from their Density Functional Theory (DFT) molecular orbital energies provide further support for the suggested assignments of the title compounds.

Synthesis of Novel Tritopic Hydrazone Ligands: Spectroscopy, Biological Activity, DFT, and Molecular Docking Studies

“…This can be attributed to the presence of terminal aromatic rings, e.g., thiophene, pyrrole attached to the azomethine nitrogen [ 52 , 53 ]. As reported earlier, the C-S single bond distance is 1.82 Å [ 52 ] while the double bond is 1.68 Å [ 54 ]. In this study, the calculated C–S bond distance of L1 was found to be 1.75 Å.…”