Journal of Molecular Structure最新文献

{"title":"Photoresponsive palm-based azo-benzothiazole liquid crystals: Mesomorphic behavior and photoisomerization studies","authors":"Zhang Kai Ang ,&nbsp;Noordini M. Salleh ,&nbsp;Suh Mei Fong ,&nbsp;Shameer Hisham ,&nbsp;Sit-Foon Cheng","doi":"10.1016/j.molstruc.2025.144247","DOIUrl":"10.1016/j.molstruc.2025.144247","url":null,"abstract":"<div><div>The technical feasibility of palm fatty acids as biobased flexible alkyl chain was investigated through the synthesis of azo-benzothiazole palm-based liquid crystals (PBLCs). Two series of PBLCs with ethoxy (−OCH₂CH₃, <strong>E1</strong> – <strong>E4</strong>) and methoxy (−OCH₃, <strong>M2</strong> − <strong>M4</strong>) terminal substituents at the sixth position on the benzothiazole moiety were successfully synthesized using palm fatty acids, namely, caprylic acid, palmitic acid, stearic acid and oleic acid. Optical microscopic study revealed that all synthesized PBLCs are purely nematogenic, where the azo linkages, terminal alkoxy substituent and biobased flexible alkyl chain facilitated the single mesophase formation. Notably, a longer flexible chain can decrease the nematic stability and the presence of unsaturation in the flexible chain lowers the nematic stability. UV–Visible spectroscopic analysis confirmed the reversible photoisomerization behavior in solution state of all PBLCs synthesized at 25 °C, 35 °C and 45 °C, with UV-A initiated <em>E</em>-<em>Z</em> isomerization and thermal <em>Z</em>-<em>E</em> relaxation in the dark. Kinetic studies revealed that the <em>E-Z-E</em> isomerization of all synthesized PBLCs follows first-order kinetics. While increasing temperature enhanced the isomerization rates, it concurrently reduced the <em>E-Z</em> photoisomerization conversion efficiency (CE). Substituting methoxy moiety with ethoxy terminal group of PBLCs increases their <em>E-Z</em> photoisomerization rate but decreases their <em>Z-E</em> isomerization rate. The results establish palm fatty acids as effective, renewable spacers for designing photoresponsive nematogens and provide structure–property relationship for optical information, display, and light-gated material applications. These findings also demonstrated the synergistic role of molecular structure and alkyl spacer design in modulating mesophase behavior and photoswitching kinetics, offering insights into the development of biobased-derived photoresponsive LC materials while showcasing the potential of oleochemicals in advanced functional materials.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144247"},"PeriodicalIF":4.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145271226","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":"Autophagy induction in TNBC cells by 5,15-diazaporphyrins: synthesis, X-ray structure, ROS generation and photodynamic efficiencies","authors":"Jaydeepsinh Chavda ,&nbsp;Nidhi Singh ,&nbsp;Hemant Kumar ,&nbsp;Dhiraj Bhatia ,&nbsp;Iti Gupta","doi":"10.1016/j.molstruc.2025.144246","DOIUrl":"10.1016/j.molstruc.2025.144246","url":null,"abstract":"<div><div>A series of novel 5,15-diazaporphyrins having <em>N-</em>substitutions in place of C-5 and C-15 atoms were synthesized and characterized. The substitution of N-5 and N-15 atoms in the core led to highly planar diazaporphyrin ring and intense absorption band between 640 and 700 nm. All the diazaporphyrins exhibited strong fluorescence around 640 nm with 4–29 % emission quantum yields. The <em>in-vitro</em> photocytotoxicity studies of diazaporphyrins on triple-negative breast cancer cells revealed excellent autophagy activation. The homoleptic diazaporphyrin displayed excellent IC₅₀ value (1.1 µM) in combination with chloroquine. The diazaporphyrins colocalized in the endoplasmic reticulum and caused stress in cancer cells. One of the diazaporphyrin acted as excellent autophagy inducer and enhanced the expression of autophagy marker proteins as established by western blot analysis. The autophagy inducing 5,15-diazaporphyrins are promising candidates as theragnostic agents for triple negative breast cancer.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144246"},"PeriodicalIF":4.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270038","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":"1,3,4-thiadiazole derivatives as antidiabetic agents: Design, synthesis, biological evaluation, and in silico studies","authors":"Dattatraya S. Kale ,&nbsp;Samin A. Shaikh ,&nbsp;Rahul T. Bhoi ,&nbsp;Ganesh R. Borse ,&nbsp;Sanjay B. Sonawale","doi":"10.1016/j.molstruc.2025.144226","DOIUrl":"10.1016/j.molstruc.2025.144226","url":null,"abstract":"<div><div>The present work reports the design, synthesis, and evaluation of twelve 1,3,4-thiadiazole derivatives (<strong>9a–9l</strong>) as potential antidiabetic agents. The compounds were screened for α-amylase and α-glucosidase inhibition, with several showing moderate to strong activity. Notably, compounds <strong>9e, 9f,</strong> and <strong>9i</strong> exhibited the most potent effects with IC₅₀ values of 19.25 ± 0.183 μM, 18.71 ± 0.015 μM, and 18.78 ± 0.136 μM, respectively, comparable to standard inhibitors. Molecular docking studies supported the experimental findings by highlighting stabilizing hydrogen bonding and hydrophobic interactions with key catalytic residues of α-glucosidase and α-amylase. Structure–activity relationship (SAR) analysis suggested the role of halogen and alkyl substitutions in enhance potency. While the results indicate that thiadiazole scaffolds hold promise as anti-hyperglycemic leads, further optimization, ADMET profiling, and in vivo validation will be essential advance these derivatives toward therapeutic development.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144226"},"PeriodicalIF":4.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270275","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":"Highly efficient non-doped deep blue organic light-emitting diodes based on a pyreno[4,5-d]imidazole derivative with narrowband emission and small efficiency roll-off","authors":"Yulong Liu ,&nbsp;Wenjun Liu ,&nbsp;Li Zeng ,&nbsp;Hongchao Huo ,&nbsp;Suxian Ke ,&nbsp;Xu Fan ,&nbsp;Ying Fu","doi":"10.1016/j.molstruc.2025.144202","DOIUrl":"10.1016/j.molstruc.2025.144202","url":null,"abstract":"<div><div>Based on the straightforward architecture, rapid response, and support for flexible screens, organic light-emitting diodes (OLEDs) have found extensive applications in modern lighting and display systems. With technological advancements, OLEDs have evolved from early fluorescent types to phosphorescent emitters, and eventually to third-generation systems such as MR-TADF and HLCT emitters. However, blue OLED materials continue to face challenges in stability and efficiency because of their inherently wide bandgap characteristics. In this study, we present a rational design for two deep blue materials, C–PyIN and N–PyIN, achieved by linking a pyreno[4,5-<em>d</em>]imidazole (PyI) unit with a naphthalene moiety via a benzene bridge. Photophysical studies and theoretical calculations reveal that C-PyIN possesses a unique hybridized local and charge-transfer (HLCT) state property, whereas N–PyIN displays pure local excitation (LE) state emission. Notably, non-doped OLEDs incorporating C–PyIN and N–PyIN as emissive materials exhibit electroluminescent (EL) peaks at 440 nm and 444 nm, with CIE coordinates of (0.15, 0.08) and (0.15, 0.11), narrow full width at half maximum (FWHM) of 56 and 57 nm, and impressive external quantum efficiencies (EQEs) of 8.3 % and 5.0 %, respectively. More significantly, non-doped OLEDs employing C–PyIN and N–PyIN demonstrate exceptionally low efficiency roll-offs of merely 1.5 % and 6 % at a luminance of 1000 cd m^–², respectively. These findings demonstrate that C-PyIN and N-PyIN are promising deep blue light-emitting materials with excellent electroluminescence performance and stability, contributing to the advancement of efficient deep blue OLEDs.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144202"},"PeriodicalIF":4.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270634","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":"Using bridging ligands to regulate pyrazole carboxylic acid coordination polymers: Investigating crystal structure and electrochemiluminescence properties","authors":"Yun-Hua Jiang ,&nbsp;Chao Feng ,&nbsp;Dao-Hang Du ,&nbsp;Wen-Juan Sun ,&nbsp;Jia Yang ,&nbsp;Shi-Hong Zhu ,&nbsp;Ting Tao ,&nbsp;Shu-Li Yu ,&nbsp;Hong Zhao ,&nbsp;Guo-Ning Zhang ,&nbsp;Yu-Cheng Wang","doi":"10.1016/j.molstruc.2025.144234","DOIUrl":"10.1016/j.molstruc.2025.144234","url":null,"abstract":"<div><div>In this study, we synthesized two novel coordination molecular complexes, Ni(HL)₂(H₂O)₂ (<strong>1</strong>) and Cu(HL)₂(H₂O)₂ (<strong>2</strong>), using 5-(4-methylphenyl)-1H-pyrazole-3-carboxylic acid (H₂L) as the primary ligand. Structural extension using 4,4′-bipyridine linker resulted in two new complexes: [Ni(HL)₂(4,4′-bipy)]ₙ (<strong>3</strong>) and [Cu₃(L)₂(4,4′-bipy)]ₙ (<strong>4</strong>). The four crystalline materials were studied by single-crystal and powder X-ray diffraction methods. Hirshfeld surface analysis showed that hydrogen bonds dominate in the supramolecular packing. Remarkably, complexes <strong>3</strong> and <strong>4</strong> exhibited emergent electrochemiluminescence (ECL) in DMSO solutions, with complex <strong>4</strong> achieving high-intensity emission albeit with signal attenuation, while complex <strong>3</strong> demonstrated baseline stability.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144234"},"PeriodicalIF":4.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269850","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":"Anti-adipogenic and antioxidant benzophenone dimers from the tea making leaves of cultivated Aquilaria sinensis (Lour.) Spreng","authors":"Wei Luo ,&nbsp;Hui-Zhen Zhou ,&nbsp;Qin-Zhao Kang ,&nbsp;Hu-Lan Chen ,&nbsp;Li-Mei Li","doi":"10.1016/j.molstruc.2025.144219","DOIUrl":"10.1016/j.molstruc.2025.144219","url":null,"abstract":"<div><div><em>Aquilaria sinensis</em> (Lour.) Gilg leaf has been approved as a new food raw material in China and Japan, and used as tea and other health care products. In the chemical study on the water extract of <em>A. sinensis</em> leaf, a pair of benzophenone atropisomers, named aquidibenzophenonsides A and B (<strong>1</strong> and <strong>2</strong>), as well as 10 known compounds, were isolated and identified on the basis of a comprehensive interpretation of the MS, CD, and 1D and 2D NMR spectroscopic data. Compounds <strong>1</strong> and <strong>2</strong> are a class of symmetrical benzophenone dimers, representing an unprecedented 10-membered ring system. In the DPPH and ABTS^•+ assays, compounds <strong>1</strong> and <strong>2</strong> exhibited significant antioxidant activity with IC₅₀ values between 12.24 ± 1.08 <em>µ</em>g/mL and 30.90 ± 0.40 <em>µ</em>g/mL. In the <em>in vivo</em> antioxidant activity assay, compounds <strong>1</strong> and <strong>2</strong> significantly decreased the content of reactive oxygen species (ROS) and improved the survival rate of <em>Caenorhabditis elegans</em>. Furthermore, compounds <strong>1</strong> and <strong>2</strong> could effectively reduce fat deposition in <em>C. elegans</em>. Molecular docking simulations indicated that the anti-adipogenic effects of compounds <strong>1</strong> and <strong>2</strong> may be mediated through their interaction with fatty acid synthase.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144219"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270514","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 new fluorinated hydrazone derivative as a multitarget therapeutic agent: Synthesis, crystal structure, spectroscopic characterization, Hirshfeld surface analysis, DFT/TD-DFT studies, NLO properties, in silico molecular docking, ADMET profiling, and biomimetic oxidation activity","authors":"Chaima MAOUCHE ,&nbsp;Salima TABTI ,&nbsp;Douniazed HANNACHI ,&nbsp;Amel DJEDOUANI ,&nbsp;Tinhinane LOUAILECHE ,&nbsp;Abdenour GUERRAOUI ,&nbsp;Sarra GOUDJIL ,&nbsp;Mohamed Larbi MEDJROUBI ,&nbsp;Olivier JEANNIN ,&nbsp;Helen STOECKLI-EVANS","doi":"10.1016/j.molstruc.2025.144227","DOIUrl":"10.1016/j.molstruc.2025.144227","url":null,"abstract":"<div><div>A new hydrazone molecule HL: (E)-2-fluoro-<em>N'</em>-(1-(4-hydroxy-6-methyl-2-oxo-2<em>H</em>-pyran-3-yl)ethylidene)benzohydrazide, was synthesized by condensation of 2-fluorobenzohydrazide with dehydroacetic acid. The structure of HL was confirmed using spectroscopic analysis, including NMR (¹H, ¹³C), UV-visible and infrared, and single crystal <em>X-</em>ray diffraction. This compound adopted a zwitterionic form <strong>HL’</strong> stabilized by intramolecular hydrogen bonding interactions between [N⁺—H…^-O] groups and crystallized in the monoclinic system with space group <em>P2₁/c</em>. Indeed, Hirshfeld surface analysis was performed to visualize and quantify the intermolecular interactions within the crystalline structure, revealing the presence of intermolecular contacts involving H···Ο and H···F hydrogen bonds and non-conventional C–H···H, C–H···π, and π···<em>lp</em> interactions, as well as π–π stacking. DFT calculations were carried out using the ωB97X-D functional with the 6-31+G(d) basis set. Based on DFT conceptual principles, key global molecular reactivity descriptors were obtained, including chemical hardness, electronic chemical potential, electronegativity, and electrophilicity index. Furthermore, the nonlinear optical properties of the compound <strong>HL</strong> and its tautomer <strong>HL</strong> ↔ HL’’ were explored, revealing promising potential for applications in second- and third-order NLO materials. Molecular docking studies were also conducted to evaluate the <em>in silico</em> biological activity of <strong>HL</strong> against cholinesterase enzymes, specifically acetylcholinesterase and butyrylcholinesterase. Furthermore, the physicochemical and pharmacokinetic properties of the molecule were assessed through ADMET analysis, confirming its favorable drug-likeness characteristics. In this study, we aim to evaluate the catalytic activity of <em>in-situ</em> complexes formed using <strong>HL</strong> as a catalyst with Cu^II salts, which are commonly used in the oxidation of catechol to <em>o-</em>quinone.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144227"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145271224","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, synthesis, and insecticidal activities of novel thioether derivatives","authors":"Feng Hao ,&nbsp;Lan Cai ,&nbsp;Huawen Wang ,&nbsp;Li Zhu ,&nbsp;Jiting Li ,&nbsp;Xiao Zhang ,&nbsp;Yinong Wang ,&nbsp;Ju Zhang ,&nbsp;Jingyi Li ,&nbsp;Nali Song ,&nbsp;Xia Zhao ,&nbsp;Le Cai","doi":"10.1016/j.molstruc.2025.144228","DOIUrl":"10.1016/j.molstruc.2025.144228","url":null,"abstract":"<div><div>Mosquitoes are significant vectors of diseases which cause tens of thousands of deaths annually and impose heavy treatment costs on affected regions. Although insecticides have been effective in managing pest damage, their widespread and continuous use has led to the emergence of resistance, presenting a major challenge in pest control. To address this issue, the design of novel insecticides is crucial. A series of novel thioether compounds were synthesized and characterized via a scaffold hopping strategy and their insecticidal activity against both larvae and adult mosquitoes of <em>Armigeres subalbatus</em>, as well as against <em>Brevicoryne brassicae</em> and <em>Pieris rapae</em> Linn were evaluated. All target compounds exhibited excellent insecticidal activity. The insecticidal mechanisms were investigated through Ellman’s method and molecular docking studies. Additionally, DFT calculations were used to analyze why compound <strong>A7</strong> (LC₅₀=0.0155 mg/L) showed less insecticidal activity compared to the positive control, cypermethrin (LC₅₀=0.0145 mg/L) and higher insecticidal activity compared to dichlorvos (LC₅₀=0.0469 mg/L). A 3D-QSAR model was developed to predict the efficacy of this class of compounds and the ADME properties revealed good lipophilicity and well-predicted oral bioavailability. The findings of this study are expected to contribute to the development of more effective and environmentally friendly agricultural chemicals, addressing the issue of pest resistance.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144228"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270273","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":"Research progress on a near-infrared fluorescence probe composed of carbazole skeleton for biological imaging","authors":"Jianqiang Qian ,&nbsp;Yaqin Gu ,&nbsp;Zihao Wang ,&nbsp;Mingshi Pan ,&nbsp;Dingding Li ,&nbsp;Jinfeng Ding","doi":"10.1016/j.molstruc.2025.144222","DOIUrl":"10.1016/j.molstruc.2025.144222","url":null,"abstract":"<div><div>Fluorescence imaging has become an essential, non-invasive tool in biomedical research, enabling the visualization of diseased tissues beyond the capabilities of the human eye and facilitating the distinction between healthy and pathological tissues. Among various imaging approaches, near-infrared (NIR) fluorescence imaging addresses the limitations posed by traditional fluorescence methods, such as strong tissue absorption, scattering, and background autofluorescence. NIR imaging enables deeper tissue penetration and offers higher temporal and spatial resolution <em>in vivo</em>. Therefore, NIR imaging is now widely used across life science research, medical diagnostics, image-guided surgery, and drug development.</div><div>Carbazole derivatives have emerged as promising materials for use in fluorescence imaging due to their excellent photophysical properties, chemical stability, and synthetic versatility. Although extensively explored in optoelectronics, particularly in organic light-emitting diodes, their application in the life sciences remains limited, primarily due to short emission wavelengths (around 368 nm) and insufficient biocompatibility. This review summarizes recent advances in the development and use of carbazole-based fluorophores with extended NIR emission for use in biosensing, bioimaging, and theranostics. Rational design strategies for developing NIR-emitting carbazole probes tailored for biological imaging are also discussed.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144222"},"PeriodicalIF":4.7,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270633","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":"Unraveling the direct effect of cationic methylation on molecular structure, electronic structure, and stability of pentazolate salts in an external electric field","authors":"Liu Song ,&nbsp;Zhenyu Yuan ,&nbsp;Chen Yang ,&nbsp;Guo Chen ,&nbsp;Junqi Wang ,&nbsp;Changlin Zhou ,&nbsp;Bingcheng Hu","doi":"10.1016/j.molstruc.2025.144186","DOIUrl":"10.1016/j.molstruc.2025.144186","url":null,"abstract":"<div><div>Polynitrogen compounds, particularly cyclo-pentazolate (<em>c</em>-N₅ˉ) salts, hold significant potential as high-energy-density materials but are hindered by sensitivity issues. Here, we report the synthesis and characterization of two novel methyl-functionalized pentazolate salts: methoxyammonium pentazolate (MOA⁺N₅ˉ) and dimethylbiguanidinium pentazolate (DMBG⁺N₅ˉ). Both salts exhibit onset decomposition temperatures ≥ 82 °C and low mechanical sensitivities (<em>IS</em> ≥ 30 J, <em>FS</em> ≥ 300 N). In addition to material synthesis, this study integrates cation methylation with external electric field (EEF) modulation to explore structural and electronic responses. First-principles and quantum chemical calculations demonstrate that methylation mitigates field-induced polarization across varying EEF intensities. The N–N trigger bonds within the <em>c</em>-N₅ˉ rings show remarkable structural resilience. Frontier orbital analysis reveals that the HOMO–LUMO gap responds controllably to field polarity: the gap widens under moderate positive EEF (0.002–0.006 Ry a.u.) and narrows under equivalent negative fields (-0.006 to -0.002 Ry a.u.). Electrostatic potential analysis further indicates that methylation maintains stable, large positive regions (49% for MOA⁺N₅ˉ and 61% for DMBG⁺N₅ˉ) even under field perturbations. Simulated impact sensitivities under EEF confirm enhanced mechanical stability. This work highlights the coupling effect of methylation and EEF regulation, offering new insights into the design of structurally resilient, field-tolerant energetic materials and advancing the understanding of pentazolate chemistry.</div></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":"1351 ","pages":"Article 144186"},"PeriodicalIF":4.7,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223392","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}