Synthesis, crystal structure, Hirshfeld surface investigation and comparative DFT studies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate

Abstract

The ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1), a thiazole ester, was synthesized by refluxing 1-(2-nitrobenzylidene)thiosemicarbazide and ethyl bromopyruvate. The compound is characterized by spectrometric, spectroscopic and single crystal (SC-XRD) techniques. Non-covalent interactions that are responsible for crystal packing are explored by Hirshfeld surface analysis. All theoretical calculations were performed by DFT quantum chemical methods using 6-311G(d,p) and cc-pVTZ basis sets and compared. Theoretical harmonic frequencies of ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) were optimized. Confirmation of hydrogen bonding sites was analyzed by molecular electrostatic potential (MEP) and Mulliken population analysis. The vibrational frequencies of characteristic functional groups and chemical shifts were found in good agreement with experimental assignments. Frontier molecular orbital (FMO) revealed relatively small HOMO–LUMO (highest occupied molecular orbital-lowest unoccupied molecular orbital) gape, which speaks off the nearly planar geometry and extended conjugation, as compared to the substituents with no conjugation possible. It has also been observed that –NO2 substituent plays a vital role for this relatively small HOMO–LUMO gape and overall electronic properties when compared with similar thiazole carboxylates (2–6, Table 6). Ethyl 2-[2-(2-nitrobenzylidene)hydrazinyl]thiazole-4-carboxylate (1) was also evaluated for its anti-oxidant and anti-microbial activities. Graphical Abstract

Synthesis of Arylidenehydrazinyl‐4‐methoxyphenylthiazole Derivatives: Docking Studies, Probing Type II Diabetes Complication Management Agents

“…The up‐field carbon signals in range δ 55.3–56.2 ppm were assigned to the methoxy carbons. The synthesis of compounds was further confirmed when NMR spectra were compared with literature reported similar skeleton compounds [38–45] …”

“…The synthesis of compounds was further confirmed when NMR spectra were compared with literature reported similar skeleton compounds. [38][39][40][41][42][43][44][45] After establishing the synthesis of the expected hydrazinyl-4-methoxyphenylthiazoles their biological significance was investigated by α-amylase inhibitory potential, antiglycation activity, antioxidant potential and cytotoxic behaviour by haemolytic assay.…”

Synthesis, Characterization and DFT Study of a New Family of High-Energy Compounds Based on s-Triazine, Carborane and Tetrazoles

“…Hirshfeld surface (HS) analysis is documented as an authoritative tool to qualitatively assess the nature of intermolecular interactions within crystal structures and thoroughly identify the interactions throughout the surface around the molecules [ 51 , 52 , 53 , 54 ].…”

Synthesis, Characterization, Crystal Structure and Computational Study of Third‐Order NLO Properties of Schiff bases

“…H.S. can be plotted by taking the numerous properties like d norm, d e , and d i , shape index, curvedness, and fragment patches [33–35] . The Hirshfeld surface plotted over d norm is more important than the other Hirshfeld surfaces as it provides information about the H‐bonding interactions [34,36–39] .…”

“…can be plotted by taking the numerous properties like d norm, d e , and d i , shape index, curved- ChemistrySelect ness, and fragment patches. [33][34][35] The Hirshfeld surface plotted over d norm is more important than the other Hirshfeld surfaces as it provides information about the H-bonding interactions. [34,[36][37][38][39] HS d norm utilizes blue, white, and red colors to recognize the interatomic contacts, which are longer, at Van der Waals separations, and short interatomic contacts, respectively.…”