Using the Gaussian09 software package, N-(6-(2-(dimethylamino)ethoxy)-5-fluoropyridin-3-yl)-2-(4-fluorophenyl)-5-(trifluoromethyl)pyrazolo[1,5 α]pyrimidine-7-amine(DFPA) the theoretically optimal molecular structure, vibration frequencies and related vibrational movements of the molecule were researched. The DFT(B3PW91 and B3LYP) techniques' 6-311G(d,p) basis set was used to perform quantum chemical computations. HOMO and LUMO analysis were performed for charge transfer in the molecule. NBO analysis was used to examine the stability of the molecule as a result of both charge delocalization and hyperconjugative interaction. DFT approach was used to perform MEP and expected infrared sensitivities and Raman activity are also presented. Geometric parameters of both calculated DFT methods are compatible. Binding affinity values and molecular coupling studies show that the title substance forms a stable complex with MtPanK and PanK. It is possible that the molecule has inhibitory activity against MtPanK and PanK, paving the way for new anti-tuberculosis drugs’ the development.

In this study, the structural, electronic, pharmacokinetic, and biological properties of molecule 2-(6-kloro-2-(4-klorofenil)imidazo[1,2-a]piridin-3-il)-N, N-dipropilasetamid (Alpidem), an imidazopyridine derivative anxiolytic known for its high BZ₁ (benzodiazepine-1) receptor affinity and low adverse effect profile, were comprehensively investigated by density functional theory (DFT) and in-silico methods. The alpidem molecule was optimized using the 6-311G(d, p) basis set with the B3LYP and B3PW91 methods; information on the stability and chemical reactivity of the structure was obtained via the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), molecular electrostatic potential (MEP) maps, natural bonding orbital (NBO) analysis, non-linear optical (NLO) properties, and Mulliken charge distributions. Comparative analysis of two different methods has shown that the results are consistent with each other and provide reliable data. In addition, the drug similarity, bioavailability score, bioactivity values, absorption, distribution, metabolism, and excretion (ADME) profiles of the Alpidem molecule were calculated, and it was determined that the Alpidem molecule has pharmacologically favorable properties. Within the scope of molecular docking analyses, its interactions with two different enzymes (PDB ID: 2Z5X and 4BDT) associated with Alzheimer’s disease were evaluated. The binding energy values obtained were − 8.00 kcal/mol (2Z5X) and − 9.60 kcal/mol (4BDT), respectively, and the strong binding affinity, especially with the 4BDT protein, suggests that Alpidem may be a potential inhibitor candidate in Alzheimer’s disease. This multi-level theoretical study demonstrates that Alpidem is a drug repurposing molecule not only as an anxiolytic but also in neurodegenerative diseases and provides important data that will shed light on experimental studies. The results of this multi-level theoretical study show that Alpidem is a drug repurposing molecule not only as an anxiolytic but also in neurodegenerative diseases and provides important data that will shed light on experimental studies.

In this study, seven new Mannich bases 4a-g, containing 1,2,4-triazole and 2,6-dimethylmorpholine were synthesized and characterized by 13C-NMR, 1H-NMR and IR spectroscopy. Newly synthesized compounds’ antioxidant characteristics were assessed with three different techniques (Reducing Power, Metal Chelation Activity, and Free Radical Scavenging). These compounds were also evaluated for their antimicrobial activity against 6 different bacteria. In vitro studies revealed that the synthesized compounds exhibited high metal chelating activity due to the presence of -OH, C = O, -NR₂, and -O- groups, despite their low free radical scavenging and reducing activity. Furthermore, antibacterial tests revealed that compound 4e, in particular, exhibited potent activity against six different bacterial species, demonstrating its potential as an antimicrobial agent. These results suggest that these compounds possess significant biological activities that may influence both metal ion chelating and microbial growth. These new Mannich bases were evaluated for their drug availability and absorption, distribution, metabolism, and excretion (ADME) properties using the SwissADME tool. ADME analysis results showed that the newly synthesized compounds could find application in the field focused on the production of effective and harmless pharmacological drugs. Molecular docking analysis was performed to investigate the potential Alzheimer’s disease activities of the newly synthesized compounds with BChE (PDB: 6SAM) and GST (PDB: 5J41) enzymes. In molecular docking analysis, compound 4d with enzyme 6SAM (docking score − 9.91) and compound 4e with enzyme 5J41 (docking score − 8.37) among the synthesized compounds showed good results on potential Alzheimer’s disease. In addition, SAR analysis was performed by calculating the HOMO-LUMO, ΔE values of the new compounds with DFT. SAR analysis results were compared with ADME, molecular docking analysis, and antimicrobial activity results. The high metal chelation and antimicrobial activities obtained in this study were consistent with the DFT-based HOMO-LUMO energy differences (ΔE) calculated from the electronic structures of the compounds. In particular, compounds with low energy differences exhibited both high binding affinity to target enzymes in molecular docking studies and effective results in biological assays, demonstrating a strong correlation between experimental findings and theoretical calculations. This consistency demonstrates that the biological activities of compounds are directly related to their molecular electronic properties and that computational approaches can guide the design of effective compounds.

In this study, the target molecule ethyl-2-(5-nitro-5'-(4-nitrophenyl)-2-oxo-3'H-spiro[indoline-3,2'-[1,3,4]oxadiazol]-1-yl)acetate, which is a spiroindoline derivative, were performed NBO analysis, molecular electrostatic potential surface (MEPS), nonlinear optics (NLO), HOMO-LUMO energy calculations, optimized molecular geometry, and mulliken atomic charges using B3LYP/B3PW91 basis set and 6-311G(d,p) approximations. Calculated results were reported. Density Functional Theory (DFT) computations were utilized to research the molecule theoretically. Moreover, molecular docking analysis of the tested compound, a spiroindoline derivative molecule targeting aldose reductase against diabetic complications, was performed using molecular docking to determine the structure-activity connection. The molecular docking study provided important information worth considering for further research. A notable outcome of bioisosteric and isosteric substitutions is the alteration in lipophilic character, an impressive characteristic in several aspects. Thus, utilizing SwissADME, lipophilic character assessments were performed for the concerned compounds.

The 6-311G(d,p) and SDD basis sets have been used to calculate the vibration frequencies, and the DFT/B3LYP approach was used to optimize the structure. The energy gap of the molecule has been calculated using the lowest unoccupied molecular orbital (LUMO) with the highest occupied molecular orbital (HOMO). The stability and charge delocalization of the Title molecule have been investigated using natural bond orbital (NBO) analysis. The dipole moment, polarizability, and first-order hyperpolarizability, as well as the molecular electrostatic potentially (MEP) and thermodynamic features, have been used to compute the nonlinear optical (NLO) behavior of the title molecule. The Schrödinger program was used to conduct molecular docking works to determine information about the interactions between the AChE and BChE enzymes and the chemical. In addition, a molecular docking study was analyzed for compounds PEP with AChE and BChE synthase binding protenins (PDB:4M0E) and (PDB:6SAM) using the Discovery Studio 2021 Client program. Compound AChE showed -7.105 kcal/mol while compounds BChE showed a inding score of -7.784 kcal/mol.

In this study, we performed HOMO-LUMO energy calculations, molecular electrostatic potential surface (MEPS), optimized molecular geometry using B3LYP, B3PW91 methods and 6-311G(d,p) basis set of the target molecule (E)-methyl 3-(1-(4-methoxybenzyl)-2,3-dioxoindolin-5-yl) acrylate (MMDA) that is an isatin derivative, nonlinear optics (NLO), NBO analysis to investigate the stability of the molecule as a function of both hyper-conjugative interactions, charge transfer within the molecule and charge delocalization, and Mulliken atomic charge structure were examined using the Gaussian 09 software, and the results were displayed. In this study, ADME analysis was performed to analyze the problem of our molecule finding application in the field, focusing on producing effective and harmless pharmacological drugs. Finally, molecular docking analysis of the examined compound on melanoma cancer were performed with two different enzymes (PDB:3OG7) and (PDB:5EG3), and docking scores and receptor models were given.