Chemical Science最新文献

{"title":"Photodynamic therapy photosensitizers and photoactivated chemotherapeutics exhibit distinct bioenergetic profiles to impact ATP metabolism","authors":"Richard J Mitchell, Dmytro Havrylyuk, Austin C Hachey, David K Heidary, Edith Glazer","doi":"10.1039/d4sc05393a","DOIUrl":"https://doi.org/10.1039/d4sc05393a","url":null,"abstract":"Energy is essential for all life, and mammalian cells generate and store energy in the form of ATP by mitochondrial (oxidative phosphorylation) and non-mitochondrial (glycolysis) metabolism. These processes can now be evaluated by extracellular flux analysis (EFA), which has proven to be an indispensable tool in cell biology, providing previously inaccessible information regarding the bioenergetic landscape of cell lines, complex tissues, and in vivo models. Recently, EFA demonstrated its utility as a screening tool in drug development, both by providing insights into small molecule-organelle interactions, and by revealing the peripheral and potentially undesired off-target effects small molecules have within cells. Surprisingly, technologies to quantify cellular bioenergetics have not been systematically applied in phototherapy development, leaving open several questions about how the mechanism of action of a compound can impact essential cellular functions. Here, we utilized the Seahorse Analyzer to address this question for photosensitizers (PSs) for photodynamic therapy (PDT) and contrast these systems to molecules that photo-release a ligand and thus act as photocages or photoactivated chemotherapeutics (PACT), intending to understand the influence these two classes of compounds have on cellular bioenergetics. EFA results show that acute treatment of A549 lung adenocarcinoma cells with PDT agents induces a quiescent bioenergetic response as a result of mitochondrial respiration shutdown. The loss of oxidative phosphorylation is followed by disruption of glycolysis, which occurs after an initial increase in glycolytic respiration is unable to compensate for the interruption of the electron transport chain (ETC). In contrast, the PACT agents tested had little impact on cellular respiration, and the minor inhibition of these metabolic processes was not related to the mechanism of action, as reflected by a lack of correlation with photoejection efficiency. Notably, a system capable of both generating 1O2 and photo-releasing a ligand exhibited the dominant profile of a PDT agent and induced the quiescent bioenergetic state, indicating potential implications on cellular bioenergetics for so-called dual-action agents. These findings are presented with the aim to provide the necessary groundwork for expanding the application and utility of EFA to phototherapeutics and to highlight the role of metabolic alterations in PDT.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"9 10 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bimodal accurate H2O2 regulation to equalize tumor-associated macrophage repolarization and immunogenic tumor cell death elicitation","authors":"Yan Zhao, Weiheng Kong, Jianqing Zhu, Fengli Qu","doi":"10.1039/d4sc06305h","DOIUrl":"https://doi.org/10.1039/d4sc06305h","url":null,"abstract":"Simultaneous implementation of tumor-associated macrophage (TAM) repolarization and immunogenic tumor cell death (ICD) elicitation enables tumor immunotherapy with high efficacy. However, the inconsistency of stimulation tolerance restricts simultaneous implementation. To address this obstacle, we validate that an H<small>₂</small>O<small>₂</small>-mediated regulatory strategy could achieve coordinated occurrences. To accomplish this, a bimodal responsive modulator is constructed, namely ZnO<small>₂</small>-ATM (ATM: 3-amino-1,2,4-triazole), as an immune adjuvant to coordinate the occurrence of TAM repolarization and ICD elicitation through the endo/exogenous synergistic responsive production of H<small>₂</small>O<small>₂</small>. H<small>₂</small>O<small>₂</small> produced by ZnO<small>₂</small>-ATM reverses the immune-suppressive TAM from an M2 to an M1 phenotype, but induces tumor cell necrosis and promotes damage-related molecular pattern release, thereby evoking ICD. This H<small>₂</small>O<small>₂</small>-mediation bimodal responsive therapeutic strategy to induce the synergistic occurrence of TAM repolarization and ICD elicitation promotes effective immune effects against tumors, demonstrating that the ZnO<small>₂</small>-ATM nanoadjuvant could be expected to provide new tools and paradigms for antitumor immunotherapy.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"71 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BINAP-CuH-catalysed enantioselective allylation using alkoxyallenes to access 1,2-syn-tert,sec-diols","authors":"N. Navaneetha, Sundaram Maurya, Prativa Behera, Sandip B. Jadhav, Lakshmi Revati Magham, Jagadeesh Babu Nanubolu, Lisa Roy, Rambabu Chegondi","doi":"10.1039/d4sc07002j","DOIUrl":"https://doi.org/10.1039/d4sc07002j","url":null,"abstract":"Herein, we present an economical method for highly enantioselective and diastereoselective Cu-BINAP-catalysed reductive coupling of alkoxyallenes with a range of electronically and structurally diverse ketones to afford 1,2-<em>syn-tert</em>,<em>sec</em>-diols, using PMHS as the hydride source. This reductive coupling has also been efficiently employed in the enantioselective desymmetrization of prochiral cyclic ketones harboring quaternary centres, in high yields with exclusive diastereoselectivity. Density Functional Theory (DFT) calculations are used to elucidate that the reaction is facilitated by a kinetically favourable “open” <em>Z</em>-enolate copper–alkoxyallene conformer, occurring at a lower Gibbs free energy barrier (by 3.9 kcal mol<small>⁻¹</small>) than its <em>E</em>-enolate counterpart, dictating the stereoselectivity. Subsequently, this <em>Z</em>-enolate conformer synchronizes with appropriate nucleophilic faces to achieve the targeted <em>syn</em>-diastereoselectivity in the product through six-membered chair-like transition states during ketone addition.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"16 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rational Design of Organic Diradicals with Robust High-Spin Ground State Based on Antiaromatic Linkers","authors":"Raul Santiago Piera, M.Angels Carvajal, Jordi Poater, Ibério de P. R. Moreira, Stefan T. Bromley, Mercè Deumal, Jordi Ribas-Ariño","doi":"10.1039/d4sc05225k","DOIUrl":"https://doi.org/10.1039/d4sc05225k","url":null,"abstract":"Fully-organic molecules with high-spin ground states are promising building blocks for new lightweight flexible magnetic materials with potential for emerging technological applications (e.g. spintronics). In this study, we explore the potential of diradicals made of two diphenylmethyl-based open-shell cores covalently linked via different types of pentalene and diazapentalene-based antiaromatic couplers (including dibenzopentalenes and acene-inserted derivatives). Accurate electronic structure calculations have been employed to target molecular orbital topologies that favor high-spin configurations, leading to the identification of diradicals displaying robust triplet ground states. These candidates exhibit singlet-triplet energy gaps that are up to ten times the thermal energy at room temperature. These substantial gaps emerge from strong interactions between the π-systems of the open-shell centers and the antiaromatic coupler. These interactions not only result in high spin states but are also found to lead to an enhanced stability of the diradicals by drastically dampening their inherent antiaromatic character as compared to the bare couplers and promoting a high degree of spin density delocalization. These findings highlight the potential of pentalene-based diradicals as building blocks for developing new advanced fully organic magnetic materials.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"6 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly selective custom reduction products for hydrogenation of CO2-derived urea derivatives or carbamates","authors":"Jun Zhu, Yongtao Wang, Jia Yao, Haoran Li","doi":"10.1039/d4sc06814a","DOIUrl":"https://doi.org/10.1039/d4sc06814a","url":null,"abstract":"Catalytic hydrogenation of CO<small>₂</small>-derived urea derivatives or carbamates provides an indirect and efficient solution for the chemical transformation of CO<small>₂</small> under mild conditions, avoiding the high temperatures and pressure required for direct catalysis to overcome the thermodynamic energy barrier and the low yield of the targeted product. However, the reported catalyst systems focus mainly on the preparation of one specific product, especially switching the product type requiring external acid/base additives, which limits the development of this protocol. Here, we report a promising route for the hierarchical reduction of CO<small>₂</small>-derived urea derivatives or carbamates using an Ir-based PNP pincer catalyst system, enabling the selective production of specific chemicals (methanol, formamides, N-methylamines, or N,N-dimethylamines) for the first time by altering reaction conditions, especially the reaction temperature. This work demonstrates the significant potential of urea derivatives or carbamates hydrogenation for indirect conversion of CO<small>₂</small> to valuable chemicals and fuels, provides a facile temperature-dependent product-switching strategy in one catalytic system.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"14 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aluminium porphyrins catalyse the hydrogenation of CO2 withH2","authors":"Nitin Kumar, Gabriela Gastelu, Martin Zabransky, Jaroslav Kukla, Jorge Gustavo Uranga, Martin Hulla","doi":"10.1039/d4sc03665d","DOIUrl":"https://doi.org/10.1039/d4sc03665d","url":null,"abstract":"Boron-based frustrated Lewis pairs (FLPs) have become well-established catalysts for the hydrogenation of a wide range of functional groups. Conversely, aluminium-based FLP hydrogenation catalysts are less common, especially for CO2 reduction. They are mostly confined to the hydrogenation of imines, alkenes, and alkynes even though aluminium is much more abundant than boron and forms structurally related compounds. Moreover, aluminium forms penta- and hexa-coordinated complexes, which remain untested in FLP hydrogenation catalysis. Herein, we demonstrate that cationic, hexa-coordinated diaqua-meso-tetraphenylporphyrin aluminium complexes [Al(TPP)(OH2)2]X and [Al(tBuTPP)(OH2)2]X (X = Cl-, OTf-, ClO4-) form FLPs with nitrogen bases, activate H2, and reductively couple CO2 to amines, yielding N-formylamines and water. Our experimental results and DFT analysis indicate that H2 activation involves the formation of an FLP, base-promoted CO2 reduction and formate salt elimination from the FLP, as proposed for transition metal-catalyzed N-formylations. These similarities in the reaction mechanism and structure of aluminium complexes brings Al-based FLPs closer to transition metal catalysis and may enable us to apply this knowledge to ligand design to enhance main group metal-promoted hydrogenations.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"70 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural Characterization of Surface Immobilized Platinum Hydrides by Sensitivity-Enhanced 195Pt Solid State NMR Spectroscopy and DFT Calculations","authors":"Benjamin A. Atterberry, Erik Wimmer, Sina Klostermann, Wolfgang Frey, Johannes Kästner, Deven Estes, Aaron J Rossini","doi":"10.1039/d4sc06450j","DOIUrl":"https://doi.org/10.1039/d4sc06450j","url":null,"abstract":"Supported single-site platinum hydride compounds are promising heterogeneous catalysts for organic transformations. Few methods exist to describe the structures of single-site Pt catalysts with atomic resolution because of their disordered structures and low Pt loadings. Here, we study the compounds formed when bis(tri-tert-butylphosphino)platinum, Pt(PtBu3)2, is supported on dehydroxylated SiO2 or SiO2-Al2O3. First, we obtain 1H, 31P and 195Pt ssNMR spectra of four model Pt phosphine compounds with oxidation states of 0 or +2 and coordination numbers between 2 and 4. These compounds are analogs of potential structures present in the supported compounds. 195Pt ssNMR spectra were obtained using 31P{195Pt} sideband selective J-resolved and J-HMQC experiments. The measured 1H and 31P chemical shifts, 31P-195Pt J-couplings and 195Pt CS tensors are shown to be diagnostic of oxidation state and coordination number. Room temperature 1H ssNMR spectra of Pt(PtBu3)2 supported on SiO2 or SiO2-Al2O3 show diagnostic hydride NMR signals, suggesting that Pt(PtBu3)2 undergoes oxidative addition, resulting in surface hydrides and Pt-oxygen bonds to the support surface. MAS dynamic nuclear polarization (DNP) surface-enhanced ssNMR enables 31P{195Pt} correlation NMR experiments on the supported compounds. These experiments enable the measurement of the 31P-195Pt J-coupling constants and 195Pt CS tensors. Combined NMR and DFT analyses suggest that the primary surface platinum species are [HPt(PtBu3)2OSi] on SiO2 and [HPt(PtBu3)2]+[Si-O–-Al] on SiO2-Al2O3. The Pt-oxygen bond length is dependent on the support and estimated as 2.1-2.3 Å and 2.7-3.0 Å for SiO2 and SiO2-Al2O3, respectively.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"129 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular origins of exciton condensation in van der Waals heterostructure bilayers","authors":"Lillian I. Payne Torres, Anna O. Schouten, David A. Mazziotti","doi":"10.1039/d4sc04149f","DOIUrl":"https://doi.org/10.1039/d4sc04149f","url":null,"abstract":"Recent experiments have realized exciton condensation in bilayer materials such as graphene double layers and the van der Waals heterostructure MoSe<small>₂</small>–WSe<small>₂</small> with the potential for nearly frictionless energy transport. Here we computationally observe the microscopic beginnings of exciton condensation in a molecular-scale fragment of MoSe<small>₂</small>–WSe<small>₂</small>, using advanced electronic structure methods based on reduced density matrices. We establish a connection between the signature of exciton condensation—the presence of a large eigenvalue in the particle-hole reduced density matrix—and experimental evidence of exciton condensation in the material. The presence of a “critical seed” of exciton condensation in a molecular-scale fragment of a heterostructure bilayer provides insight into how local short-range strongly correlated effects may give rise to macroscopic exciton condensation. We find that molecular-scale properties such as layer alignment and interlayer distance can impact the formation of nonclassical long-range order in heterostructure bilayers, demonstrating the importance of geometric considerations for the rational design of exciton condensate materials. Mechanistic insights into the microscopic origins of exciton condensation have potential implications for the design and development of new materials with enhanced energy transport properties.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"36 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enantioselective Nickel-Catalyzed Electrochemical Reductive Conjugate Alkenylation of α,β-Unsaturated Ketones","authors":"Siriphong Somprasong, Syuzanna R. Harutyunyan, Bin Wan","doi":"10.1039/d4sc06891b","DOIUrl":"https://doi.org/10.1039/d4sc06891b","url":null,"abstract":"Catalytic electrochemical asymmetric catalysis starting to emerg as a promising strategy for the synthesis of chiral compounds. Herein, we report an asymmetric electrochemical nickel-catalysed reductive conjugate addition of alkenyl bromides/aryl iodides to α,β-unsaturated ketones in an undivided cell, leading to the addition products with high yields and excellent enantioselectivities (up to 96% yield and 96% ee).","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"44 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tandem Rh(II)-catalyzed 1,3-acyloxy migration/intermolecular [2+2] cycloaddition of electronically deficient propargylic esters with alkenes and alkynes","authors":"Zurong Xu, Dong Zhu, Rui Wu, Shifa Zhu","doi":"10.1039/d4sc06458e","DOIUrl":"https://doi.org/10.1039/d4sc06458e","url":null,"abstract":"Transition metal-catalyzed 1,3-acyloxy migration of propargylic esters represents one of the most straightforward routes to access allene intermediates, which could engage in various fascinating subsequent transformations. However, this process is often limited to propargylic esters with electron-donating group due to intrinsic electronic bias and the subsequent intermolecular reactions are quite limited. Herein, we disclosed an unprecedented Rh<small>₂</small>(II)-catalyzed 1,3-acyloxy migration of electron-deficient propargylic esters, followed by intermolecular [2+2] cycloaddition with readily available alkenes and alkynes, a large array of valuable alkylidenecyclobutane/ene scaffolds could be obtained facilely in one pot. Mechanistic studies revealed that the allene generated from Rh<small>₂</small>(II)-catalyzed 1,3-acyloxy migration of propargylic carboxylates is the key intermediate. Control experiments and NMR data indicated that the formyl group at the terminus of propargylic esters is crucial and the cooperative interactions between the substrate and the carboxylate ligand possibly play a signficant role in this reaction.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"251 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}