3-氨基-5-巯基-1,2,4-三唑与Ag(I)配位作用的密度泛函理论研究

采用密度泛函理论B3LYP方法研究3-氨基-5-巯基-1,2,4-三唑与Ag(I)的配位特点.计算结果显示,ad-L配体配位能力显著高于中性配体L,其中SN配位模式稳定化能高于中性配体约443.8kJ/mol,且N2模式稳定化能高于中性配体约336.8 kJ/mol;而p-L配体相互作用能和稳定化能均为负值.自然键轨道(NBO)分析显示配体与Ag(I)间存在较强轨道作用.静电势分析发现,L配体最负静电势出现在N1、N2原子周围,因此N1、N2位点更易与Ag(I)配位; ad-L配体静电势为负,因此与Ag(I)作用增强,而质子化的配体p-L静电势为正,因此不易与Ag(I)配位.     

分子内结构环境对解离能的影响

为了理解化学键的这一结构效应, 本文对具有相同化学键而分子内结构环境不同的系列分子进行了计算研究, 讨论了化学键结构环境对解离能的影响.     

Competition Between the Two σ-Holes in the Formation of a Chalcogen Bond

A chalcogen atom Y contains two separate σ-holes when in a R₁YR₂ molecular bonding pattern. Quantum chemical calculations consider competition between these two σ-holes to engage in a chalcogen bond (ChB) with a NH₃ base. R groups considered include F, Br, I, and tert-butyl (tBu). Also examined is the situation where the Y lies within a chalcogenazole ring, where its neighbors are C and N. Both electron-withdrawing substituents R₁ and R₂ act cooperatively to deepen the two σ-holes, but the deeper of the two holes consistently lies opposite to the more electron-withdrawing group, and is also favored to form a stronger ChB. The formation of two simultaneous ChBs in a triad requires the Y atom to act as double electron acceptor, and so anti-cooperativity weakens each bond relative to the simple dyad. This effect is such that some of the shallower σ-holes are unable to form a ChB at all when a base occupies the other site.     

Spectral analysis (FT-IR,FT-Raman,UV and NMR), molecular docking,ADMET properties and computational studies: 2-Hydroxy-5-nitrobenzaldehyde

The hybrid correlation method was used to examine the spectra of 2-Hydroxy-5-nitrobenzaldehyde (2H5NB) in the FT-IR, FT-Raman, UV–Vis and NMR ranges. For the best molecular shape, vibrational wavenumbers, infrared intensities, and Raman activity using density functional theory, B3LYP and the 6–311++G(d,p) basis set were used. The MOLVIB software was tasked with providing an in-depth interpretation of the vibrational spectra. Intermolecular charge transfer is a result of bonding orbitals participating as donors and acceptors in all phases of NBO analysis, which stabilizes molecules. High gastrointestinal absorption, but no brain-blood barrier penetration or cytochrome P450 inhibition, were observed despite the expected ADMET characteristics and expected gastrointestinal absorption (1A2, 2C19, 2C9, 2D6 and 3A4). Following CFN and EDE, the results of molecular docking showed that 2H5NB had the highest negative mean binding affinity of ?5.717 kcal/mol, followed by CFN and EDE. 2H5NB also had a more significant hydrogen bond with the amino acid residues of selected receptor proteins. As a result, the current compound may be described as a possible analeptic agent.