Journal of Molecular Structure最新文献

{"title":"A uranyl carboxyphosphonate framework exhibiting luminescence intensity, luminescence lifetime and SHG triple-response","authors":"Ge-Hua Wen,&nbsp;Hui Chen","doi":"10.1016/j.molstruc.2026.145597","DOIUrl":"10.1016/j.molstruc.2026.145597","url":null,"abstract":"<div><div>To date, no reports have been documented on triple-response temperature sensing based on luminescence intensity, luminescence lifetime, and nonlinear optics (NLO) in coordination polymers (CPs) or metal-organic frameworks (MOFs). In this study, we successfully synthesized a three-dimensional (3D) uranyl carboxyphosphonate framework, (ImH)₂[(UO₂)₅(2-pmb)₄] (<strong>1</strong>), by introducing imidazole (Im) molecules into the reaction system of 2-(phosphonomethyl)benzoic acid (2-pmbH₃) with uranyl ions. Compound <strong>1</strong> crystallizes in the polar space group <em>Cmc</em>2₁, featuring a 3D framework constructed by uranyl phosphonate chains along the <em>b</em>-axis interconnected with trinuclear uranyl carboxylate units within the <em>ac</em>-plane. Protonated imidazole molecules serve as counterions, orderly arranged between uranyl chains along the <em>b</em>-direction. The shortest U···U distance within the structure is 4.91 Å. Photoluminescence studies reveal that compound <strong>1</strong> exhibits characteristic green luminescence at room temperature, demonstrating a favorable quantum yield (8.46%) and an exceptionally long luminescence lifetime (4164.3 μs). Furthermore, its second harmonic generation (SHG) response of 0.67 × KDP at room temperature confirms the non-centrosymmetric structure. Temperature-dependent studies demonstrate that compound <strong>1</strong> enables triple-response optical thermometry through luminescence intensity (80–300 K), luminescence lifetime (80–300 K), and second harmonic generation (SHG) signal (80–160 K).</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145597"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Azo Hydrazone–Chalcone Hybrids: DFT and experimental insights into spectroscopic and redox behavior","authors":"Nafeesa Naeem ,&nbsp;Charlene Marais ,&nbsp;Marrigje Marianne Conradie ,&nbsp;Mustafa S. Alluhaibi ,&nbsp;Abdullah Yahya Abdullah Alzahrani ,&nbsp;Amina Sadiq ,&nbsp;Ernst H.G. Langner ,&nbsp;Marthinus Rudi Swart ,&nbsp;Nandisiwe GS Mateyise ,&nbsp;Jeanet Conradie ,&nbsp;Ehsan Ullah Mughal","doi":"10.1016/j.molstruc.2026.145534","DOIUrl":"10.1016/j.molstruc.2026.145534","url":null,"abstract":"<div><div>Three hydrazone–chalcone hybrid compounds (<strong>1</strong>–<strong>3</strong>) were synthesized and investigated using spectroscopic, electrochemical, and computational methods. UV–Vis spectroscopy and TD-DFT calculations reveal two main absorption bands: a low-energy band at 480–500 nm arising from a hydrazone-localized HOMO → LUMO (π→π*) transition, and higher-energy bands (300–350 nm) associated with chalcone-centered excitations. Cyclic voltammetry shows a first diffusion-controlled reduction near –1.3 V vs. Fc/Fc⁺, significantly less negative than for simple chalcones, indicating hydrazone-based reduction, followed by a second chalcone-centered reduction at more negative potentials. The reduction potentials correlate inversely with DFT-calculated LUMO energies, consistent with sequential electron addition to hydrazone- and chalcone-centered orbitals. These results demonstrate that the hydrazone moiety governs the optical and redox behaviour of these hybrids, while chalcone substituents modulate higher-energy transitions.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145534"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CuAAC derived 7-azaindole and 1H-pyridin-2-one linked 1,2,3-triazole based probe for selective Pb2+ sensing endowed with in vitro and in silico antimicrobial potential","authors":"Kanika Sharma ,&nbsp;Bajrang Lal ,&nbsp;Ram Kumar Tittal ,&nbsp;Riddima Singh ,&nbsp;Jandeep Singh ,&nbsp;Vijay Kumar ,&nbsp;Ramling S. Mathpati","doi":"10.1016/j.molstruc.2026.145515","DOIUrl":"10.1016/j.molstruc.2026.145515","url":null,"abstract":"<div><div>A probe containing 7-azaindole and 1<em>H</em>-pyridin-2-one linked 1,2,3-triazole has been efficiently synthesized by CuAAC method and successfully characterized up to single crystal X-ray diffraction data to establish the structure as 1-[1-(2-pyrrolo[2,3-b]pyridin-1-yl-ethyl)-1<em>H</em>-[1,2,3]triazol-4-ylmethyl]-1<em>H</em>-pyridin-2-one (<strong>5</strong>). The synthesized probe <strong>5</strong> was examined under UV–Vis analysis, which revealed its specific sensitivity towards Pb²⁺ ion among other metal ions with LOD of 30 µM and binding constant (<em>K_a</em>) of 8.25 × 10³ M⁻¹. Intermolecular interactions of the probe have been studied through Hirshfeld surface analysis and energy framework calculations. Probe showed best potency for <em>A. niger</em> (MIC: 0.0195 µmol/mL) fungal strain which is even less than Fluconazole drug (MIC: 0.0408 µmol/mL) and showed considerable potency for bacterial strains (<em>P. aeruginosa, Escherichia coli, S. aureus</em>, and <em>B. subtilis</em>) including other fungal strain <em>C. albicans</em>. Molecular docking and DFT studies showed agreement with the <em>in-vitro</em> results while establishing extent of binding interactions between probe and metal ion. Furthermore, the in silico pharmacokinetic profile and cytotoxicity predicted results of the probe may attract theoreticians and experimentalist to design and propose development of similar molecules that may satisfy the parameters of orally bioavailable drug.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145515"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review of 9, 9-Dimethyl-9, 10-dihydroacridine (DMAC) derivatives as thermally activated delayed fluorescence emitters in OLED applications","authors":"Masoud Dehghanipour ,&nbsp;Zahra Nasresfahani","doi":"10.1016/j.molstruc.2026.145590","DOIUrl":"10.1016/j.molstruc.2026.145590","url":null,"abstract":"<div><div>Thermally Activated Delayed Fluorescence (TADF) has emerged as a game changer in the field of organic light-emitting diodes (OLEDs). By cleverly harnessing both singlet and triplet excitons, TADF offers a compelling pathway to achieve high internal quantum efficiencies (IQEs) without relying on expensive and often problematic rare-earth metals used in phosphorescent materials. This review focuses on TADF emitters utilizing at least one 9,9-Dimethyl-9,10-dihydroacridine (DMAC) unit as a donor and is structured according to different acceptor building blocks, including, triazines, pyrimidines, sulfones, carbonyls, anthraquinones, pyridines, borons, and others, along with material design strategies, device performance, and future prospects. The incorporation of acridine derivatives into OLED materials can enhance the efficiency and stability of light emission, making them promising candidates for next-generation display technologies. The distinctive planar structure of acridine allows for effective π-π stacking, facilitating charge transport and exciton formation in the organic layers. Furthermore, acridine's ability to emit light in a wide range of colors (red, green, blue, and white) is particularly valuable. Herein, the recent developments of DMAC derivatives is methodically summarized, that structure–property relationships focused on two fundamental factors of interest for TADF emitters, including, frontier molecular orbitals separation and minimal singlet–triplet energy gap (ΔE_ST) and OLED applications. It is anticipated that this review will provide a comprehensive overview of the role of this acridine analog in advancing OLED materials and present exciting possibilities for both scientific research and commercial applications.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145590"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quinoline-imidazo[1,2-a]pyridine conjugates as potential antioxidant agents: Synthesis, experimental and theoretical approaches","authors":"Houria Bouria ,&nbsp;Hayette Alliouche ,&nbsp;Arif Mermer ,&nbsp;Yakup Sirin ,&nbsp;Burak Tüzün ,&nbsp;Rafik Bensegueni ,&nbsp;Mohamed Imed Chouiter ,&nbsp;Hasan Küçükbay ,&nbsp;Ali Belfaitah","doi":"10.1016/j.molstruc.2026.145622","DOIUrl":"10.1016/j.molstruc.2026.145622","url":null,"abstract":"<div><div><em>N</em>-heterocyclic compounds such as quinolines and imidazopyridines are very important structures in medicinal chemistry, especially for drug development. In this work, a series of novel quinoline-imidazo[1,2-<em>a</em>]pyridines hybrids (<strong>IMP1-10</strong>) were synthesized from 3-(quinolin-3-yl) oxirane-2,2-carbonitriles (<strong>1-10</strong>) via a nucleophilic ring-opening reaction and were characterized by conventional analytical techniques. The antioxidant capacity of the synthesized compounds was investigated using the DPPH, FRAP and ABTS methods, and it was found that <strong>IMP-7</strong> exhibited the best DPPH and FRAP activity with an IC₅₀ values of 0,33 ± 0,05 µM and 2387,45 ± 23,25 μmol TE/g, respectively. In the course of the analysis of the ABTS assay results, <strong>IMP-10</strong> was found to demonstrate the highest activity, with an IC₅₀ value of 0.67 ± 0.04 µM. The antioxidant mechanism properties of the most potent compounds <strong>IMP-7, IMP-8</strong> and <strong>IMP-10</strong> were calculated with the Gaussian package program using HF/6-31++G(d,p) basis set.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145622"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and synthesis of a chitosan-based fluorescent probe functionalized with CN-styrylanthracene and triazole for selective detection of Al³⁺ in aqueous environment","authors":"Khaoula Hassine,&nbsp;Habiba Zrida,&nbsp;Mariam Essid,&nbsp;Khaled Hriz","doi":"10.1016/j.molstruc.2026.145558","DOIUrl":"10.1016/j.molstruc.2026.145558","url":null,"abstract":"<div><div>As part of the valorization of marine co-products, this work explores the use of chitosan from shrimp shells for the development of fluorescent metal cation sensors. A high purity chitosan (97% deacetylation), obtained with a yield of 45%, served as a skeleton for the development of a new water-soluble and fluorescent biomaterial. The functionalization was carried out in two steps: a 1,3-dipolar cycloaddition reaction (click chemistry) between chitosan azide and a propargylated derivative of vanillin, then a Knoevenagel condensation with cyanomethylanthracene followed by a deprotection leading to the compound <strong><em>Cs-Tri-An-CN</em></strong> simultaneously bearing triazole and cyano-styrylanthracene units. Structural characterization by NMR and FT-IR spectroscopies confirmed the successful modification of chitosan, yielding <strong><em>Cs-Tri-An-CN</em></strong> with a conversion rate of 21%. Optical studies (UV–Vis and fluorescence) revealed its organic semiconductor behavior, characterized by blue emission. The sensing performance of <strong><em>Cs-Tri-An-CN</em></strong> was evaluated by monitoring the photoluminescence quenching of its dilute solutions in the presence of various metal cations. It exhibited a remarkable quenching (44%) for Al³⁺ cation, with a Stern-Volmer constant (Kₛᵥ) of 6.8 × 10³ M⁻¹. The calculated detection limit (LOD) of 3.6 μM confirms the material's potential for monitoring Al³⁺ in drinking water.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145558"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystal engineering, electronic structure and docking study of bis(2-amino-6-methylpyridinium) oxalate","authors":"Emna Jaziri ,&nbsp;Sibel Demir Kanmazalp ,&nbsp;Yusuf Sert ,&nbsp;Mücahit Özdemir ,&nbsp;Bahattin Yalçın ,&nbsp;Cherif Ben Nasr ,&nbsp;Lamia Khedhiri","doi":"10.1016/j.molstruc.2025.145067","DOIUrl":"10.1016/j.molstruc.2025.145067","url":null,"abstract":"<div><div>Single crystals of the novel organic salt bis(2-amino-6-methylpyridinium) oxalate were synthesized and characterized. X-ray diffraction revealed a 3D supramolecular network stabilized primarily by N–H···O hydrogen bonds. Hirshfeld surface and energy framework analyses showed that dispersive and electrostatic forces dominate the crystal packing, with significant π-π interactions and steric repulsions. Computational studies, including FMO and MEP analyses, indicated a moderate band gap and identified potential reactive sites. Molecular docking revealed a moderate but favorable binding affinity (-8.5 kcal·mol^-1) for carbonic anhydrase II, comparable to that of the reference inhibitor Acetazolamide (-6.3 kcal·mol^-1), suggesting that the compound may act as a potential CA-II inhibitor with stable interactions. These results highlight the compound's well-defined solid-state structure and its promising potential as a carbonic anhydrase inhibitor for pharmaceutical development</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145067"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anion-directed structural hierarchies in a new o-chloroanilinium salt: Comparative crystallographic insights across the o-chloroanilinium family","authors":"Houda Boussekine ,&nbsp;Radhwane Takouachet ,&nbsp;Rim Benali-Cherif ,&nbsp;Lynda Golea ,&nbsp;Wahiba Falek ,&nbsp;Erwann Jeanneau ,&nbsp;Nourredine Benali-Cherif","doi":"10.1016/j.molstruc.2026.145615","DOIUrl":"10.1016/j.molstruc.2026.145615","url":null,"abstract":"<div><div>In the search for hybrid materials with well-defined supramolecular organization, we report the synthesis, single-crystal structure determination, and comparative crystallographic analysis of a new <em>o</em>-chloroanilinium hydronium sulfate salt (compound 1). The main purpose of this study is to establish an anion-directed “supramolecular hierarchy” framework within the o-chloroanilinium family, i.e., to demonstrate in a controlled series (invariant cation, variable counter-anion) how the anion governs dimensionality, interaction cooperativity, and packing anisotropy rather than merely balancing charge. High-resolution X-ray diffraction at 100 K reveals a robust framework supported by cooperative hydrogen bonding, halogen bonding, and π–π stacking, generating a dense layered architecture with a high degree of structural coherence. A systematic comparison with eight closely related <em>o</em>-chloroanilinium structures extracted from the Cambridge Structural Database shows that the nature of the counter-anion critically governs supramolecular dimensionality and packing efficiency. Whereas halide- and phosphate-based analogues display ribbon-like or weakly ordered arrangements, the sulfate–hydronium pair induces a highly organized lamellar assembly in which charge-assisted N–H···O and O–H···O bridges, C–Cl···O contacts, and well-defined π–π interactions operate cooperatively to reinforcing structural cohesion and directional packing of the lattice. To establish whether this variability originates from the anion or the cation itself, a geometric overlay of all nine structures confirms that the <em>o</em>-chloroanilinium cation exhibits an almost invariant conformation across the series, demonstrating that the observed supramolecular diversity originates from anion-driven assembly rather than cationic deformation. Hirshfeld surface analysis provides a quantitative picture of the dominant contacts defining the solid-state architecture, while complementary density functional theory calculations clarify the electrostatic landscape and orbital alignment that support the observed interaction hierarchy. Together, these results establish a transferable anion-directed design principle in which the counter-anion acts as the primary architect of supramolecular order, with the sulfate–hydronium sublattice delivering the most coherent and anisotropic packing within the o-chloroanilinium family.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145615"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spermine and spermidine derivatives from the earthworm Pheretima aspergillum: Protective role in age-related renal fibrosis and immunosuppressive effects","authors":"Shu-Ping Yang ,&nbsp;Li-Li Chen ,&nbsp;Xiao-Ning Liu ,&nbsp;Bin-Yuan Hu ,&nbsp;Ke-Ming Li ,&nbsp;Yong-Xian Cheng","doi":"10.1016/j.molstruc.2026.145616","DOIUrl":"10.1016/j.molstruc.2026.145616","url":null,"abstract":"<div><div><em>Pheretima aspergillum</em> (E. Perrier), commonly known as the earthworm, is a widely utilized medicinal animal in China, renowned for its broad spectrum of pharmacological properties. In the present study, seven undescribed spermine and spermidine derivatives, pheraspermines <em>A</em> − <em>G</em> (<strong>1</strong> − <strong>7</strong>), along with one known analogue (<strong>8</strong>), were isolated from the <em>Pheretima aspergillum</em>. Notably, compound <strong>8</strong> was identified as a natural product for the first time. The structures of all compounds were elucidated using spectroscopic techniques, including UV, 1D/2D NMR, and HRESIMS. Biological evaluation revealed that compound <strong>1</strong> showed dose-dependent protection against age-related renal fibrosis, while compound <strong>4</strong> exhibited immunosuppressive effects on T cells by flow cytometric analysis.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145616"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heterocyclic substituent impact on the geometry and biological activity of biguanidine derivatives","authors":"Muhammad Fathiy Mutalabisin ,&nbsp;Hayedeh Gorjian ,&nbsp;Mohd Rafie Johan ,&nbsp;Chin Fei Chee ,&nbsp;Nurshamimi Nor Rashid ,&nbsp;Nader Ghaffari Khaligh","doi":"10.1016/j.molstruc.2026.145548","DOIUrl":"10.1016/j.molstruc.2026.145548","url":null,"abstract":"<div><div>Four biguanidine derivatives with heterocyclic substituents, i.e., morpholine and 1-methylpiperazine, were prepared to investigate the impact of heterocyclic substituents on the geometry and antimicrobial activity of biguanidines. The chemical structure of the biguanidine salts was characterized by various spectroscopic techniques. Fortunately, the suitable crystals of two salts of <em>C</em>-[(4-methyl-piperazine-1-carboximidoyl)-amino]-<em>C</em>-(4-methyl-piperazin-1-yl)-methylene-ammonium chloride (<strong>1</strong>) and <em>C</em>-guanidino-<em>C</em>-morpholin-4-yl-methylene-ammonium chloride (<strong>4</strong>) were isolated to study the impact of monomorpholine and bis(1-methylpiperazine) substituent on biguanidine geometry. Biguanidine salt <strong>1</strong> crystallized in a monoclinic system with a space group of P2₁/n, and compound 4 was in an orthorhombic system with a space group of Pbca. The crystallography data revealed that the addition of one or two heterocyclic substituents causes no significant changes in bond length and angle in the biguanidine moiety; however, there was an increase in biguanidine torsion. Morpholine and 1-methylpiperazine rings exist in a chair conformation, and CN₃ in guanidyl and NC3 in morpholine and 1-methylpiperazine rings, linked to guanidinyl moieties, imply a trigonal planar structure with a Csp2 and Nsp2 hybridization. The pharmacokinetics/ADMET properties and Lipinski's rule of five drug-likeness of biguanidine derivatives were predicted by the SwissADME. The ProToX-III prediction tool was employed for <em>in silico</em> toxicity evaluation. <em>In-vitro</em> cytotoxicity screening using HepG2 cells exhibited non-toxicity of biguanidine derivatives in the range of 3.125‒100 μg mL⁻¹. Furthermore, the <em>in vitro</em> antibacterial activity of biguanidine derivatives and alexidine against <em>Staphylococcus aureus</em> (<em>S. aureus</em>) and <em>Escherichia coli</em> (<em>E. coli</em>) was investigated using the broth microdilution method, which demonstrated high antibacterial activity of all derivatives with MIC values at a range of 7.81-250 μg mL⁻¹. Alexidine bearing two biguanidine moieties linked by a hexamethylene carbon spacer exhibited the highest <em>in vitro</em> antibacterial activity against <em>E. coli</em> and <em>S. aureus</em>. Compound <strong>1</strong> exhibited more potent antibacterial activity with MICs of 7.81 μg mL⁻¹ for <em>E. coli</em> and 31.25 μg mL⁻¹ for <em>S. aureus</em>. The results revealed a slight impact of mono- and bis-heterocyclic substituents on the geometry and structural parameters; however, significant differences were observed in the pharmacokinetic properties, toxicity, and antibacterial activities of biguanidine derivatives.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1360 ","pages":"Article 145548"},"PeriodicalIF":4.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146192421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}