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Employment of Molecularly Imprinted Polymers to High-Throughput Screen nNOS-PSD-95 Interruptions: Structure and Dynamics Investigations on Monomer-Template Complexation.

Molecularly imprinted polymers (MIPs) are employed to screen nNOS-PSD-95 (neuronal nitric oxide synthase post-synaptic density protein-95) interruptions. 5-(3,5-Dichloro-2-hydroxybenzylamino)-2-hydroxybenzoic acid (ZL006; a potential drug candidate for the treatment of stroke, depression, and pain) is employed as a template. Four kinds of functional monomers (2-VP: 2-vinylpyridine; 4-VP: 4-vinylpyridine; MMA: methyl methacrylate; and MAAM: methacrylamide) are designed, and their complexation with ZL006 in various solvents (methanol, acetonitrile, toluene, chloroform) is investigated by molecul

Self-association behavior of a novel nonproteinogenic β-strand-mimic in an organic solvent.

The self-association behavior of a newly characterized β-strand-mimic, presented by an achiral nonproteinogenic model system Boc-γ-Abz-NHMe (1: Boc = tert-butyloxycarbonyl; γ-Abz = γ-aminobenzoic acid; NHMe = N-methylamide), have been investigated using (1)H NMR and FT-IR absorption spectroscopy, in combination with computational ab initio calculations. The concentration dependence of (1)H NMR chemical shifts of the amide-NHs in CDCl3 exhibited noncooperative behavior of self-association, whereas the variable temperature (1)H NMR chemical shifts data of the amide-NHs, i.e., temperature-coeffic

Enhancing the stability and solubility of esculetin by cucurbit[n]uril (n = 6-8) encapsulation: A computational study to identify the Ideal host.

Esculetin (Eu) is a naturally occurring secondary metabolite with ethnopharmacological significance and is widely used as an anti-inflammato … [n], with a cooperative effect of van der Waals interactions predominantly in the Eu@CB[6] complex. Quantum Theory of Atoms in Molecules (QTAIM), Dispersion Interaction Density (DID), and Local Energy Decomposition (LED) analyses show that hydrogen bonding between Eu and the carbonyl portal of CBs plays a major role in stabilization, with a significant attractiv …

Tuning hydrogen dissociation on Zn12O12 nanocages via first-row transition metal encapsulation: DFT insights for hydrogen storage.

CONTEXT: Hydrogen storage applications require efficient catalysts for the hydrogen dissociation reaction (HDR). This work evaluates the cat … ed through natural bond orbital (NBO) analysis, electron density difference (EDD) analysis, and the quantum theory of atoms in molecules (QTAIM). All calculations were performed using Gaussian09 with Multiwfn 3.7 for QTAIM.

Proton-transfer dictated supramolecular hydrogen bonded architecture in cytosine with substituted carboxylic acid coformers: Experimental and theoretical investigation by density functional approximations, DLPNO-CCSD(T)-F12, and G0W0 calculations.

The nucleobase cytosine has been utilized for co-crystallization with three coformers (gallic acid, aspirin, and thiazole-4-carboxylic acid) … dditionally performed to assess their reliability for predicting these gaps. Bonding analysis using quantum theory of atoms in molecules (QTAIM), non-covalent interaction (NCI), natural bond orbital, and molecular electrostatic potential was carried out at the DSD-PBEP86-D3BJ/def2-TZVP level of theory, validated against seven additional DFAs. QTAIM reveals that …

Synthesis of Novel Arylhydrazones Bearing 8-Trifluoromethyl Quinoline: Crystal Insights, Larvicidal Activity, ADMET Predictions, and Molecular Docking Studies.

Background/Objectives: Vector-borne diseases like malaria remain a major global health concern, worsened by insecticide resistance in mosquito populations. Quinoline-based compounds have been extensively studied for their pharmacological effects, including antimalarial and larvicidal properties. Modifying quinoline structures with hydrazone groups may enhance their biological activity and physicochemical properties. This study reports the synthesis, structural characterization, and larvicidal testing of a new series of aryl hydrazones (6a-i) derived from 8-trifluoromethyl quinoline. Methods: C

Mechanistic Evaluation of Radical Scavenging Pathways in Ginger Phenolics: A DFT Study of 6-Gingerol, 6-Shogaol, and 6-Paradol.

Understanding the molecular determinants of antioxidant activity in natural phenolic compounds is essential for explaining their biological … SMD solvation model. Frontier molecular orbital (FMO), molecular electrostatic potential (MEP), and quantum theory of atoms in molecules (QTAIM) analyses were employed to correlate electronic structure with reactivity. The results reveal a distinct solvent-dependent mechanistic crossover. In the gas phase and benzene, the low dielectric constant suppresses charg …

Сравнительное исследование нанокапсулы на основе кавитанд как средства доставки наркотиков для исследования по борьбе с раком и множественным склерозом - DFT.

Системы доставки наркотиков с помощью наносферы обеспечивают платформу для изменения элементарных свойств, связанных с частицами наркотиков, в целях ограничения их неблагоприятного воздействия. В этой связи считается, что в качестве средства доставки наркотиков используется глубокая димерическая нанокапсула на основе бензимидазолона. В настоящем исследовании мы сообщали о нанокапсулах на основе бензимидазолона как о системах доставки наркотиков, т.е. ампира (АМ) и merceptopin (MP) на уровне теории M06-2x/6-31G(d,p). АМ и MP-медики взаимодействуют с нанокапсулой с энергиями взаимодействия -26,0

Совпадение в аннотации оригинала
Nanoscale-assisted drug delivery systems give a platform to alter elementary properties associated with drug particles to limit their advers … h the interaction energies of -26.02 kcal mol-1 and -24.01 kcal mol-1, respectively. The results of quantum theory of atoms in molecules (QTAIM) and non-covalent index (NCI) analyses divulge that both the drug molecules are stabilized inside nanocapsule via the hydrogen bonding and van der Waals interactions. The transfer of charge is confirmed through electron …

Carbones as Ligands in Novel Main-Group Compounds E[C(NHC)2 ]2 (E=Be, B+ , C2+ , N3+ , Mg, Al+ , Si2+ , P3+ ): A Theoretical Study.

Quantum chemical calculations of the main-group compounds E[C(NHCMe )2 ]2 (E=Be, B+ , C2+ , N3+ , Mg, Al+ , Si2+ , P3+ ) have been carried out using density functional theory at the BP86/def2-TZVPP and BP86-D3(BJ)/def2-TZVPP levels of theory. The geometry optimization at BP86/def2-TZVPP gives equilibrium structures with two-coordinated species E and bending angles C-E-C between 152.5° (E=Be) and 110.5° (E=Al). Inclusion of dispersion forces at BP86-D3(BJ)/def2-TZVPP yields a three-coordinated beryllium compound Be[C(NHCMe )2 ]2 as the only energy minimum form. Three-coordinated isomers are fou

Beyond the Isolated Halogen-Bond Dimer: Cooperative and Anticooperative Motifs in C6F4I2···HMTA.

Halogen bonding (XB) is often analyzed in terms of isolated dimers, yet under realistic solution conditions, it coexists with a dense, rapidly fluctuating network of weaker contacts whose net effect on bond strength is difficult to quantify. Here, we combine gas-phase quantum-chemical calculations with explicit-solvent ab initio molecular dynamics (AIMD) in chloroform to dissect how specific noncovalent interactions modulate the I···N halogen bond in ortho-, meta-, and para-C6F4I2···HMTA complexes. Gas-phase DFT, Quantum Theory of Atoms in Molecules (QTAIM), Natural Bond Orbital (NBO), and SAP…

Identifying Band Inversions in Topological Materials Using Diffusion Monte Carlo.

Topological insulators are characterized by insulating bulk states and robust metallic surface states. Band inversion is a hallmark of topological insulators. At time-reversal invariant points in the Brillouin zone, spin-orbit coupling (SOC) induces a swapping of orbital character at the bulk band edges. Reliably detecting band inversion in solid-state systems with many-body methods would aid in identifying possible candidates for spintronics and quantum computing applications and improve our understanding of the physics behind topologically nontrivial systems. Density functional theory (DFT)

Monte Carlo study on the imaging performance of powder Lu2SiO5:Ce phosphor screens under x-ray excitation: comparison with Gd2O2S:Tb screens.

Lu2SiO5: Ce (LSO) scintillator is a relatively new luminescent material which has been successfully applied in positron emission tomography systems. Since it has been recently commercially available in powder form, it could be of value to investigate its performance for use in x-ray projection imaging as both physical and scintillating properties indicate a promising material for such applications. In the present study, a custom and validated Monte Carlo simulation code was used in order to examine the performance of LSO, under diagnostic radiology (mammography and general radiography) conditi

Unveiling the gas-sensing potential of methylene-bridged [6]cycloparaphenylene nanobelt: a DFT perspective.

The rapid expansion of industrialization has led to the release of numerous toxic gases into the atmosphere, posing significant environmenta … states near the Fermi level, confirming enhanced charge transfer upon gas adsorption. Additionally, quantum theory of atoms in molecules (QTAIM), electron localization function (ELF), and non-covalent interaction (NCI) analyses identified van der Waals forces as the dominant stabilizing interactions, with notably strong attractive regions for [6]MCPP@O₃, [6]MCPP …

Synthesis, X-ray structure, in silico calculation, and carbonic anhydrase inhibitory properties of benzylimidazole metal complexes.

Three coordination compounds of formula {M(bmim)2Cl2} were synthetised (M = Co, Zn, and Hg) and fully characterised. Each complex incorporates 1-benzyl-2-methylimidazole (bmim) as ligand. The coordination polyhedron around the metal center for all complexes has a quasi-regular tetragonal geometry. Density functional theory calculations were carried out on the title compounds and as well on hypothetical complexes (Cu, Ni), in order to elucidate their electronic and molecular structure. The calculations reproduced the Co, Zn, and Hg experimental structures and could predict stable complexes in t

Drastically reducing the cost of the XsTD-DFT family of methods using a minimal auxiliary basis set (ηXsTD-DFT) to efficiently treat ultra large systems.

This contribution introduces the ηXsTD-DFT family of methods in which the exact integral simplified time-dependent density functional theory (XsTD-DFT) is adapted considering the resolution of identity (RI) approximation with a minimal auxiliary basis set. The main goal of this is to provide to the community the most efficient simplified quantum chemistry method to compute excited states and response properties for all-atom quantum mechanical (AQM) methodologies. This auxiliary set is composed of 1s orbitals with the square of the atomic chemical hardness η scaled by a global factor θ as param

Quantum Chemical and Trajectory Surface Hopping Molecular Dynamics Study of Iodine-Based BODIPY Photosensitizer.

A computational study of I-BODIPY (2-ethyl-4,4-difluoro-6,7-diiodo-1,3-dimethyl-4-bora-3a,4a-diaza-s-indacene) has been carried out to investigate its key photophysical properties as a potential triplet photosensitizer capable of generating singlet oxygen. Multireference CASPT2 and CASSCF methods have been used to calculate vertical excitation energies and spin-orbit couplings (SOCs), respectively, in a model (mono-iodinated BODIPY) molecule to assess the applicability of the single-reference second-order algebraic diagrammatic construction, ADC(2), method to this and similar molecules. Subseq

The Long and Short Radii for Hydrogen in Hydrogen Bonded Complexes.

Hydrogen bonding was initially identified by comparing the distance between the heavy atoms D and A in a DH•••A hydrogen bond, to the sum of their van der Waals (vdW) radii as locating the H atom was not possible. In recent years, hydrogen bond radii (HBR) have been defined for typical hydrogen bond donors DH and acceptors, A. However, both these approaches make an unreasonable assumption of treating all the atoms as spheres. This study advances the understanding of hydrogen bond distances by estimating the shape of hydrogen atoms in HD molecules and in A•••HD complexes through electron de

Overcoming van der Waals Bundling: Molecular Wedges Enable Sonication-Free Dispersion of Single-Walled Carbon Nanotubes.

Single-walled carbon nanotubes (SWCNTs) naturally bundle due to strong van der Waals interactions, posing a significant challenge to their dispersion and applications. Conventional methods require ultrasonication or extended shear mixing, which are energy-intensive, can damage the nanotubes, and/or incur high process costs and low throughput. Here, we show that small molecular wedges, which are formed by reacting wedge precursors (e.g., 1-octanol, ammonia, n-hexylamine) with minimal amounts of superacids (e.g., chlorosulfonic acid, CSA), can intercalate the nanotube bundles, markedly reducing

Rational design of local electric fields: an effective strategy to modulate thermally activated delayed fluorescence in carbene-gold(I)-amide complexes.

Carbene-metal-amide-based thermally activated delayed fluorescence (CMA-TADF) compounds are promising emerging metal-organic materials for OLEDs. However, there is a lack of systematic studies on the influence of external electric fields (EEFs) on the underlying photophysical mechanisms of conformationally distinct CMA complexes. In this work, we employ density functional theory (DFT) and time-dependent DFT (TD-DFT) methods to elucidate how EEFs of specific orientation and magnitude govern the excited-state properties and dynamics of coplanar (CAAC-Au-Ptz-1) versus perpendicular (CAAC-Au-Ptz-2