Tetrahedron最新文献

{"title":"Organocatalytic-assisted synthesis of 1,2,3-triazoles mediated by chitosan beads","authors":"Gustavo B. Blödorn ,&nbsp;Henrique P. Mota ,&nbsp;André R. Fajardo ,&nbsp;Diego Alves","doi":"10.1016/j.tet.2025.134916","DOIUrl":"10.1016/j.tet.2025.134916","url":null,"abstract":"<div><div>In this study, we explore the potential of chitosan beads as an organocatalyst for the synthesis of 1,2,3-triazoles. The chitosan beads were prepared using a straightforward coagulation process, yielding beads with a narrow size distribution (2.34 ± 0.21 mm), significant porosity, and high stability under proposed experimental conditions. Under optimized conditions, the chitosan beads (20 mg) exhibited efficient catalytic activity, assisting the synthesis of diverse 1,4,5-trisubstituted-1,2,3-triazoles with yields ranging from 27 % to 97 %. The protocol proved compatible with 1,3-diketones, β-keto-esters, and α-cyano-ketones, while azides bearing electron-withdrawing groups demonstrate enhanced efficiency compared to electron-donating counterparts. Importantly, the bead-like structure of chitosan was shown to be crucial in achieving high yields of 1,2,3-triazoles. This study introduces chitosan as a green and versatile organocatalyst for synthesizing valuable organic compounds like triazoles, offering new insights into its application in sustainable chemistry.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134916"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144989088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recyclable deep eutectic solvent (DES) assisted metal free one-pot synthesis of aza-anthraquinone scaffolds, and their docking (SAR) studies, biological activity and fluorescent properties","authors":"Umarani Nampally ,&nbsp;Neeli Satyanarayana ,&nbsp;Anisetti Ravindernath ,&nbsp;Venkateswarlu Banoji ,&nbsp;Gottumukkala Devi Sree ,&nbsp;Gottumukkala Devi Priya ,&nbsp;Kapilavayi V. Basava Ranjitha","doi":"10.1016/j.tet.2025.134911","DOIUrl":"10.1016/j.tet.2025.134911","url":null,"abstract":"<div><div>We report a metal-free, efficient green synthetic approach for the synthesis of substituted Aza-anthraquinone scaffolds from the multicomponent reaction of aromatic aldehydes, active methylene substrates (2a/2b), and 2-aminonaphthalene-1,4-dione (3a) employing a recyclable eco-friendly Urea-ZnCl₂ (3:1) deep eutectic solvent (DES) as catalyst cum reaction medium. This protocol effectively synthesizes functionalized Aza-anthraquinone hybrids, exhibiting high atom economy and exclusive regioselectivity, while achieving remarkable yields and demonstrating scalability to gram quantities. Notable benefits include the utilization of inexpensive starting materials, compatibility with various scaffolds, and an innovative eco-friendly methodology that employs deep eutectic solvents as green organocatalysts and solvents. Further, synthesized substates were analyzed photophysical characterization that revealed promising photophysical properties, with compounds 4d and 4h exhibiting intense emission bands at 562 and 546, respectively, accompanied by large Stokes shifts (117 and 80 nm). Additionally, biological evaluation highlighted significant antifungal and antibacterial activities, with compounds 4b, 4d, 4e, 4f, 4g, 4l, and 4b respectively displaying greater inhibition zones against standard drugs (Gentamicin for antibacterial, Nystatin for antifungal assays). Additionally, molecular docking studies evaluated synthesized molecules, using Glide tool in the Maestro Schrodinger suite, for antiviral activity against remdesivir (antiviral drug) with SARS-CoV-2 protein, which indicated that compound <strong>4a</strong> possesses a glide score of −5.64 kcal/mol, glide energy of −41.27 kcal/mol, and 89.79 % bioavailability, suggesting it's potential as an antiviral molecule against SARS-CoV-2 protein.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134911"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144989087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Penrhizovarin A, a novel indole diterpene from endophytic fungi Penicillium sp. KYG-9","authors":"Dong Gan ,&nbsp;Jin-Hua Yu ,&nbsp;Da-Mei Wang ,&nbsp;Jie-Zhen Shi ,&nbsp;Le Cai ,&nbsp;Zhong-Tao Ding","doi":"10.1016/j.tet.2025.134914","DOIUrl":"10.1016/j.tet.2025.134914","url":null,"abstract":"<div><div>One novel indole diterpene penrhizovarin A (<strong>1</strong>) and one known analogue (<strong>2</strong>), were characterized from <em>Penicillium</em> sp. KYG-9. Structural elucidation was accomplished through comprehensive spectroscopic analyses, including high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), X-ray crystallography, and electronic circular dichroism (ECD) calculations. Penrhizovarin A (<strong>1</strong>) is the first reported indole diterpene characterized by both an unprecedented F-ring cleavage and a novel 4/6/6/6/5–6/6/6 pentacyclic scaffold incorporating a rare dioxabicyclo[3.3.1]nonane unit. The single crystal of <strong>2</strong> was obtained for the first time, and its planar structure and stereochemistry were further confirmed by X-ray single crystal diffraction. <em>In vitro</em> bioassays revealed that penrhizovarin A exhibited potent cytotoxicity against all tested human cancer cell lines, with particularly notable activity against HL-60 (leukemia), A-549 (lung cancer), and SW-480 (colon cancer) cell lines, surpassing the activity of the positive control cisplatin. Additionally, penrhizovarin A demonstrated significant antifungal activities.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134914"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent developments in the synthesis of amidines","authors":"Arash Ghaderi ,&nbsp;Dariush Khalili ,&nbsp;Hengameh Havasel","doi":"10.1016/j.tet.2025.134893","DOIUrl":"10.1016/j.tet.2025.134893","url":null,"abstract":"<div><div>Amidines are a common functionality found in a variety of naturally occurring compounds, valuable bioactive molecules, and pharmaceuticals. Synthesis of amidine derivatives has attracted considerable attention by organic chemists in recent years due to their wide potential applications, especially in medicinal chemistry, making them an exciting candidate for drug discovery. In this review, we have compiled the latest advances reported over the last few years for the synthesis of amidines (2018–present), focusing on diverse synthetic pathways conducted under different conditions. This provides valuable information for understanding the chemistry of amidine derivatives, offering insights into their potential as key intermediates for the development of novel bioactive compounds and pharmaceutical agents.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134893"},"PeriodicalIF":2.2,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144989180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy-efficient copper-catalyzed synthesis of N-aryl anthranilic acids using concentrated solar radiation","authors":"Santosh S. Chikane ,&nbsp;Dipak V. Pinjari ,&nbsp;Pawan R. Kudale ,&nbsp;Pranit B. Patil ,&nbsp;Bharat G. Pawar ,&nbsp;Nitin D. Arote","doi":"10.1016/j.tet.2025.134909","DOIUrl":"10.1016/j.tet.2025.134909","url":null,"abstract":"<div><div><em>N</em>-Aryl anthranilic acids play a crucial role in synthetic chemistry due to their pharmaceutical applications. An environmentally sustainable approach has been developed for the copper-catalyzed synthesis of <em>N</em>-aryl anthranilic acids, utilizing concentrated solar radiation (CSR) as a renewable energy source under aqueous and solvent-free conditions. This method enables the expeditious and selective synthesis of <em>N</em>-aryl anthranilic acids, achieving yields of up to 93 % under mild conditions. Furthermore, the synthetic applicability of the current method is demonstrated by synthesizing pharmaceutical compounds such as tolfenamic acid and mefenamic acid on a gram scale. This method substantially reduces energy consumption by 79–97 % compared to conventional approaches. This eco-friendly method presents a promising alternative to traditional synthesis techniques, highlighting the potential of CSR in advancing sustainable chemical processes.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134909"},"PeriodicalIF":2.2,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144922516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CuMgMn layered double hydroxide acts as a multifunctional catalyst for the efficient synthesis of quinolines through cascade reactions","authors":"Yongsheng Zhou,&nbsp;Jie Yao,&nbsp;Jiaqi Yan,&nbsp;Xuan Dai,&nbsp;Anwei Wang,&nbsp;Xue Zhou,&nbsp;Weiyou Zhou","doi":"10.1016/j.tet.2025.134908","DOIUrl":"10.1016/j.tet.2025.134908","url":null,"abstract":"<div><div>CuMgMn layered double hydroxide (LDH) has been developed as a multifunctional catalyst for the efficient synthesis of quinolines employing <em>o</em>-aminobenzyl alcohol and methyl ketone as substrates. Quinolines are produced through cascade reactions that include oxidative dehydrogenation, coupling and cyclization. Control experiments demonstrated that CuMgMn-LDH can accelerate all three reactions without any additives. Specifically, Mn species were identified as the catalytically active site for the oxidative dehydrogenation, while Cu species were found to be responsible for the coupling and cyclization reactions. Consequently, an effective and convenient protocol based on CuMgMn-LDH for the construction of quinoline skeleton has been developed. Various <em>o</em>-aminobenzyl alcohols and methyl ketones can be well tolerated by the methodology. The catalytic system also demonstrates excellent catalytical and structural stability, as well as recyclability.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134908"},"PeriodicalIF":2.2,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144926456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in the synthesis of heteropolyquinanes","authors":"Sambasivarao Kotha ,&nbsp;Ramakrishna Reddy Keesari ,&nbsp;Yellaiah Tangella ,&nbsp;Mohammad Salman","doi":"10.1016/j.tet.2025.134899","DOIUrl":"10.1016/j.tet.2025.134899","url":null,"abstract":"<div><div>In view of applications of heteropolyquinanes in various fields of science and their presence in diverse bioactive natural products, these ring systems are studied extensively. Their structural diversity and functional significance have attracted considerable attention in synthetic organic chemistry, medicinal chemistry, and materials science. Among them, aza-/oxa-polyquinanes possess interesting biological properties and play significant role in material science as high-density candidates, due to their unique molecular architecture and electronic characteristics. This review demonstrates our own efforts as well as several other contributions that led to the building of various heteropolyquinanes and related molecules. The article also highlights important synthetic methods, structural features, and possible applications to give a clear picture of the progress made in this field.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134899"},"PeriodicalIF":2.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A recent overview of the synthesis of fluorenes and their analogs","authors":"Sreenivasulu Chinnabattigalla ,&nbsp;Ravi Kishore Dakoju ,&nbsp;Satyanarayana Gedu","doi":"10.1016/j.tet.2025.134896","DOIUrl":"10.1016/j.tet.2025.134896","url":null,"abstract":"<div><div>Fluorenes represent an essential class of fused tricyclic aromatic compounds embedded with two aromatic rings, with diverse applications in organic electronics, pharmaceuticals, and functional materials. Recent advancements in their synthesis have introduced efficient methodologies, including transition-metal catalysis, oxidative cascade processes, and carbene-mediated transformations. These strategies enabled precise structural modifications, facilitating access to highly functionalized fluorenes with tailored electronic and optical properties. Additionally, novel enantioselective approaches have broadened the scope for synthesizing chiral fluorene derivatives. This review provides a comprehensive overview of these synthetic advancements from 2021 to 2025, highlighting key reaction mechanisms, functional group compatibility, and their broader impact on materials and medicinal chemistry.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134896"},"PeriodicalIF":2.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applications of Conia-ene reaction in total synthesis of natural products","authors":"Zhongting Ruan ,&nbsp;Huaxuan Zhang ,&nbsp;Fuhai Liu,&nbsp;Xingang Xie","doi":"10.1016/j.tet.2025.134901","DOIUrl":"10.1016/j.tet.2025.134901","url":null,"abstract":"<div><div>The Conia-ene reaction is an intramolecular alkenylation (or alkylation) reaction occurring at the carbonyl α position of unsaturated ketones and serves as a highly efficient transformation for the construction of cyclic ketones, especially those within five- or six-membered rings frequently encountered within natural products. Compared with the traditional thermal-promoted transformation, Lewis acid catalyzed Conia-ene features mild conditions and widely tolerable functional groups thereby has been widely applied in the synthesis of natural products. In this review, we briefly introduce the development of the Conia-ene reaction, recent advancements in protocols, and a comprehensive review of its application in the total synthesis of natural products.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134901"},"PeriodicalIF":2.2,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144912045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resorcinarene bearing carbanion ion pair as organocatalyst for carbon dioxide fixation","authors":"Yongzhu Hu,&nbsp;Haoyu Wang,&nbsp;Zhenjiang Li,&nbsp;Yujia Wang,&nbsp;Min Zhang,&nbsp;Xin Yuan,&nbsp;Xin Zou,&nbsp;Chunyu Li,&nbsp;Tianyu Zhu,&nbsp;Kai Guo","doi":"10.1016/j.tet.2025.134897","DOIUrl":"10.1016/j.tet.2025.134897","url":null,"abstract":"<div><div>The development of efficient and environmentally friendly catalysts for carbon dioxide (CO₂) cycloaddition remains a significant challenge due to the corrosion, pollution, and purity issues caused by conventional halide-containing systems. Herein, we present a halide-free tetra-1,3-diketone resorcinarene ion pair organocatalyst that facilitates CO₂ fixation under mild conditions (120 °C, 0.1 MPa) through a dual activation mechanism—CO₂ activation by the resorcinarene carbanion and epoxide activation via H-bonding. This catalytic system has been shown to achieve high conversion (83–99 %) for terminal epoxides, retain notable activity for internal epoxides, and demonstrate exceptional thermal stability (&gt;230 °C) and recyclability (five cycles without significant loss of activity). This system offers a sustainable alternative to traditional halide catalysts, combining environmental advantages with practical industrial feasibility.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":"187 ","pages":"Article 134897"},"PeriodicalIF":2.2,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}