Yong Li, Kaiwei Zhang, Jian Chen, Leigang Zhang, Fayun Feng, Jinjin Cheng, Liya Ma, Mei Li, Ya Wang, Wayne Jiang, Xiangyang Yu
Although exogenous chemicals frequently exhibit a biphasic response in regulating plant growth, characterized by low-dose stimulation and high-dose inhibition, the underlying mechanisms remain elusive. This study demonstrates, for the first time, the compensatory function of rhizosphere microbiota in assisting plants to withstand pesticide stress. It was observed that pak choi plants, in response to foliar-spraying imidacloprid at both low and high doses, could increase the total number of rhizosphere bacteria and enrich numerous beneficial bacteria. These bacteria have capabilities for promoting plant growth and degrading the pesticide, such as Nocardioides, Brevundimonas, and Sphingomonas. The beneficial bacterial communities were recruited by stressed plants through increasing the release of primary metabolites in root exudates, such as amino acids, fatty acids, and lysophosphatidylcholines. At low doses of pesticide application, the microbial compensatory effect overcame pesticide stress, leading to plant growth promotion. However, with high doses of pesticide application, the microbial compensatory effect was insufficient to counteract pesticide stress, resulting in plant growth inhibition. These findings pave the way for designing improved pesticide application strategies and contribute to a better understanding of how rhizosphere microbiota can be used as an eco-friendly approach to mitigate chemical-induced stress in crops.
{"title":"Rhizosphere Bacteria Help to Compensate for Pesticide-Induced Stress in Plants.","authors":"Yong Li, Kaiwei Zhang, Jian Chen, Leigang Zhang, Fayun Feng, Jinjin Cheng, Liya Ma, Mei Li, Ya Wang, Wayne Jiang, Xiangyang Yu","doi":"10.1021/acs.est.4c04196","DOIUrl":"https://doi.org/10.1021/acs.est.4c04196","url":null,"abstract":"<p><p>Although exogenous chemicals frequently exhibit a biphasic response in regulating plant growth, characterized by low-dose stimulation and high-dose inhibition, the underlying mechanisms remain elusive. This study demonstrates, for the first time, the compensatory function of rhizosphere microbiota in assisting plants to withstand pesticide stress. It was observed that pak choi plants, in response to foliar-spraying imidacloprid at both low and high doses, could increase the total number of rhizosphere bacteria and enrich numerous beneficial bacteria. These bacteria have capabilities for promoting plant growth and degrading the pesticide, such as <i>Nocardioides</i>, <i>Brevundimonas</i>, and <i>Sphingomonas</i>. The beneficial bacterial communities were recruited by stressed plants through increasing the release of primary metabolites in root exudates, such as amino acids, fatty acids, and lysophosphatidylcholines. At low doses of pesticide application, the microbial compensatory effect overcame pesticide stress, leading to plant growth promotion. However, with high doses of pesticide application, the microbial compensatory effect was insufficient to counteract pesticide stress, resulting in plant growth inhibition. These findings pave the way for designing improved pesticide application strategies and contribute to a better understanding of how rhizosphere microbiota can be used as an eco-friendly approach to mitigate chemical-induced stress in crops.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-05DOI: 10.1021/acs.jpclett.4c01175
Xufeng Xu, Francesco Stellacci
Protein-protein interactions (PPIs) differ when measured in test tubes and cells due to the complexity of the intracellular environment. Free amino acids (AAs) and their derivatives constitute a significant fraction of the intracellular volume and mass. Recently, we have found that AAs have a generic property of rendering protein dispersions more stable by reducing the net attractive part of PPIs. Here, we study the effects on PPIs of different AA derivatives, AA mixtures, and short peptides. We find that all the tested AA derivatives modulate PPIs in solution as effectively as AAs. Furthermore, we show that the modulation effect is additive when AAs form mixtures or are bound into short peptides. Therefore, this study demonstrates the additive effects of a class of small molecules (i.e., AAs and their biological derivatives) on PPIs and provides insights into rationally designing biocompatible molecules for stabilizing protein interactions and consequently tuning protein functions.
由于细胞内环境的复杂性,在试管和细胞中测量蛋白质与蛋白质之间的相互作用(PPIs)会有所不同。游离氨基酸(AA)及其衍生物占细胞内体积和质量的很大一部分。最近,我们发现 AAs 具有一种通用特性,即通过减少 PPIs 的净吸引部分而使蛋白质分散更加稳定。在此,我们研究了不同 AA 衍生物、AA 混合物和短肽对 PPI 的影响。我们发现,所有测试过的 AA 衍生物都能像 AA 一样有效地调节溶液中的 PPI。此外,我们还发现当 AA 形成混合物或与短肽结合时,其调节作用是相加的。因此,本研究证明了一类小分子(即 AAs 及其生物衍生物)对 PPIs 的叠加效应,并为合理设计生物相容性分子以稳定蛋白质相互作用并进而调整蛋白质功能提供了启示。
{"title":"Amino Acids and Their Biological Derivatives Modulate Protein-Protein Interactions in an Additive Way.","authors":"Xufeng Xu, Francesco Stellacci","doi":"10.1021/acs.jpclett.4c01175","DOIUrl":"https://doi.org/10.1021/acs.jpclett.4c01175","url":null,"abstract":"<p><p>Protein-protein interactions (PPIs) differ when measured in test tubes and cells due to the complexity of the intracellular environment. Free amino acids (AAs) and their derivatives constitute a significant fraction of the intracellular volume and mass. Recently, we have found that AAs have a generic property of rendering protein dispersions more stable by reducing the net attractive part of PPIs. Here, we study the effects on PPIs of different AA derivatives, AA mixtures, and short peptides. We find that all the tested AA derivatives modulate PPIs in solution as effectively as AAs. Furthermore, we show that the modulation effect is additive when AAs form mixtures or are bound into short peptides. Therefore, this study demonstrates the additive effects of a class of small molecules (i.e., AAs and their biological derivatives) on PPIs and provides insights into rationally designing biocompatible molecules for stabilizing protein interactions and consequently tuning protein functions.</p>","PeriodicalId":62,"journal":{"name":"The Journal of Physical Chemistry Letters","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532836","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}
Pub Date : 2024-07-05DOI: 10.1021/acs.jpclett.4c01634
Paolo Cleto Bruzzese, Yu-Kai Liao, Lorenzo Donà, Bartolomeo Civalleri, Enrico Salvadori, Mario Chiesa
To use transition metal ions for spin-based applications, it is essential to understand fundamental contributions to electron spin relaxation in different ligand environments. For example, to serve as building blocks for a device, transition metal ion-based molecular qubits must be organized on surfaces and preserve long electron spin relaxation times, up to room temperature. Here we propose monovalent group 12 ions (Zn+ and Cd+) as potential electronic metal qubits with an ns1 ground state. The relaxation properties of Zn+ and Cd+, stabilized at the interface of porous aluminosilicates, are investigated and benchmarked against vanadium (3d1) and copper (3d9) ions. The spin-phonon coupling has been evaluated through DFT modeling and found to be negligible for the ns1 states, explaining the long coherence time, up to 2 μs, at room temperature. These so far unexplored metal qubits may represent viable candidates for room temperature quantum operations and sensing.
{"title":"Spin-Lattice Relaxation and Spin-Phonon Coupling of <i>n</i>s<sup>1</sup> Metal Ions at the Surface.","authors":"Paolo Cleto Bruzzese, Yu-Kai Liao, Lorenzo Donà, Bartolomeo Civalleri, Enrico Salvadori, Mario Chiesa","doi":"10.1021/acs.jpclett.4c01634","DOIUrl":"https://doi.org/10.1021/acs.jpclett.4c01634","url":null,"abstract":"<p><p>To use transition metal ions for spin-based applications, it is essential to understand fundamental contributions to electron spin relaxation in different ligand environments. For example, to serve as building blocks for a device, transition metal ion-based molecular qubits must be organized on surfaces and preserve long electron spin relaxation times, up to room temperature. Here we propose monovalent group 12 ions (Zn<sup>+</sup> and Cd<sup>+</sup>) as potential electronic metal qubits with an <i>n</i>s<sup>1</sup> ground state. The relaxation properties of Zn<sup>+</sup> and Cd<sup>+</sup>, stabilized at the interface of porous aluminosilicates, are investigated and benchmarked against vanadium (3d<sup>1</sup>) and copper (3d<sup>9</sup>) ions. The spin-phonon coupling has been evaluated through DFT modeling and found to be negligible for the <i>n</i>s<sup>1</sup> states, explaining the long coherence time, up to 2 μs, at room temperature. These so far unexplored metal qubits may represent viable candidates for room temperature quantum operations and sensing.</p>","PeriodicalId":62,"journal":{"name":"The Journal of Physical Chemistry Letters","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532838","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}
Pub Date : 2024-07-05DOI: 10.1021/acs.jpca.4c02386
Alexander M Mebel, Wang Li, Luna Pratali Maffei, Carlo Cavallotti, Alexander N Morozov, Chang-Yang Wang, Jiu-Zhong Yang, Long Zhao, Ralf I Kaiser
To understand the reactivity of resonantly stabilized radicals, often found in relevant concentrations in gaseous environments, it is important to determine their main reaction pathways. Here, it is investigated whether the fulvenallenyl radical (C7H5·) reacts preferentially with closed-shell molecules or radicals. Electronic structure calculations on the C10H9 potential energy surface accessed by the reactions of C7H5· with methylacetylene (CH3CCH) and allene (H2CCCH2) were combined with RRKM-ME calculations of temperature- and pressure-dependent rate constants using the automated EStokTP software suite and kinetic modeling to assess the reactivity of C7H5· with closed-shell unsaturated hydrocarbons. Experimentally, the reactions were attempted in a chemical microreactor heated to 998 ± 10 K by preparing fulvenallenyl radicals via pyrolysis of trichloromethylbenzene (C7H5Cl3) and seeding the radicals in methylacetylene or allene carrier gas, with product identification by means of photoionization mass spectrometry. The measured photoionization efficiency curve of m/z = 128 was assigned to a linear combination of the reference curves of two C10H8 isomers, azulene (minor) and naphthalene (major), presumably resulting from the C7H5· plus C3H4 reactions. However, the calculations demonstrated that these reactions are too slow, and kinetic modeling of processes in the reactor allowed us to conclude that the observation of naphthalene and azulene is due to the C7H5· plus C3H3· reaction, where propargyl is produced by direct hydrogen atom abstraction by chlorine (Cl) atoms from allene or methylacetylene and Cl stem from the pyrolysis of C7H5Cl3. Modeling results under the copyrolysis conditions of toluene and methylacetylene in high-temperature shock tube experiments confirmed the prevalence of the fulvenallenyl reaction with propargyl over its reactions with C3H4 even when the concentrations of allene and methylacetylene largely exceed that of propargyl. Overall, the reactions of fulvenallenyl with both allene and methylacetylene were found to be noncompetitive in the formation of naphthalene and azulene thus attesting the inefficiency of the fulvenallenyl radical reactions with the prototype closed-shell hydrocarbon species. In the meantime, the new reaction pathways revealed, including H-assisted isomerizations between C10H8 isomers and decomposition reactions of various C10H9 isomers, emerge as relevant and are recommended for inclusion in combustion kinetic models for naphthalene formation.
{"title":"Fulvenallenyl Radical (C<sub>7</sub>H<sub>5</sub><sup>·</sup>)-Mediated Gas-Phase Synthesis of Bicyclic Aromatic C<sub>10</sub>H<sub>8</sub> Isomers: Can Fulvenallenyl Efficiently React with Closed-Shell Hydrocarbons?","authors":"Alexander M Mebel, Wang Li, Luna Pratali Maffei, Carlo Cavallotti, Alexander N Morozov, Chang-Yang Wang, Jiu-Zhong Yang, Long Zhao, Ralf I Kaiser","doi":"10.1021/acs.jpca.4c02386","DOIUrl":"https://doi.org/10.1021/acs.jpca.4c02386","url":null,"abstract":"<p><p>To understand the reactivity of resonantly stabilized radicals, often found in relevant concentrations in gaseous environments, it is important to determine their main reaction pathways. Here, it is investigated whether the fulvenallenyl radical (C<sub>7</sub>H<sub>5</sub><sup>·</sup>) reacts preferentially with closed-shell molecules or radicals. Electronic structure calculations on the C<sub>10</sub>H<sub>9</sub> potential energy surface accessed by the reactions of C<sub>7</sub>H<sub>5</sub><sup>·</sup> with methylacetylene (CH<sub>3</sub>CCH) and allene (H<sub>2</sub>CCCH<sub>2</sub>) were combined with RRKM-ME calculations of temperature- and pressure-dependent rate constants using the automated EStokTP software suite and kinetic modeling to assess the reactivity of C<sub>7</sub>H<sub>5</sub><sup>·</sup> with closed-shell unsaturated hydrocarbons. Experimentally, the reactions were attempted in a chemical microreactor heated to 998 ± 10 K by preparing fulvenallenyl radicals via pyrolysis of trichloromethylbenzene (C<sub>7</sub>H<sub>5</sub>Cl<sub>3</sub>) and seeding the radicals in methylacetylene or allene carrier gas, with product identification by means of photoionization mass spectrometry. The measured photoionization efficiency curve of <i>m</i>/<i>z</i> = 128 was assigned to a linear combination of the reference curves of two C<sub>10</sub>H<sub>8</sub> isomers, azulene (minor) and naphthalene (major), presumably resulting from the C<sub>7</sub>H<sub>5</sub><sup>·</sup> plus C<sub>3</sub>H<sub>4</sub> reactions. However, the calculations demonstrated that these reactions are too slow, and kinetic modeling of processes in the reactor allowed us to conclude that the observation of naphthalene and azulene is due to the C<sub>7</sub>H<sub>5</sub><sup>·</sup> plus C<sub>3</sub>H<sub>3</sub><sup>·</sup> reaction, where propargyl is produced by direct hydrogen atom abstraction by chlorine (Cl) atoms from allene or methylacetylene and Cl stem from the pyrolysis of C<sub>7</sub>H<sub>5</sub>Cl<sub>3</sub>. Modeling results under the copyrolysis conditions of toluene and methylacetylene in high-temperature shock tube experiments confirmed the prevalence of the fulvenallenyl reaction with propargyl over its reactions with C<sub>3</sub>H<sub>4</sub> even when the concentrations of allene and methylacetylene largely exceed that of propargyl. Overall, the reactions of fulvenallenyl with both allene and methylacetylene were found to be noncompetitive in the formation of naphthalene and azulene thus attesting the inefficiency of the fulvenallenyl radical reactions with the prototype closed-shell hydrocarbon species. In the meantime, the new reaction pathways revealed, including H-assisted isomerizations between C<sub>10</sub>H<sub>8</sub> isomers and decomposition reactions of various C<sub>10</sub>H<sub>9</sub> isomers, emerge as relevant and are recommended for inclusion in combustion kinetic models for naphthalene formation.</p>","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532858","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}
Liquid crystal monomers (LCMs) are biphenyl- or cyclohexane-based organic chemicals used in electronic digital displays, and several of them possess bioaccumulative and toxic properties. Little is known about their occurrence in indoor dust from the United States. We analyzed 60 LCMs in 104 residential indoor dust samples collected from 16 states across the United States. Forty-seven of 60 LCMs were detected in dust samples at a median ∑LCM concentration of 402 ng/g (range: not detected to 4300 ng/g). Trans-4-propylcyclohexyl trans,trans-4'-propylbicyclohexyl-4-carboxylate (MPVBC) and (trans,trans)-4-fluorophenyl 4'-pentyl-[1,1'-bi(cyclohexane)]-4-carboxylate (FPeBC) were frequently detected in dust samples. We investigated potential sources of LCMs in dust by determining concentrations and profiles of these chemicals in smartphone screens, desktop and laptop computer monitors, and displays of other electronic devices and found that profiles in smartphones matched closely with those found in dust. The calculated median daily intake of ∑LCM through dust ingestion was 1.19 ng/kg bw/d for children, whereas that through dermal absorption was 0.18 ng/kg bw/d for adults in the United States.
{"title":"Concentrations, Profiles, and Potential Sources of Liquid Crystal Monomers in Residential Indoor Dust from the United States.","authors":"Yuan Liu, Kurunthachalam Kannan","doi":"10.1021/acs.est.4c03131","DOIUrl":"https://doi.org/10.1021/acs.est.4c03131","url":null,"abstract":"<p><p>Liquid crystal monomers (LCMs) are biphenyl- or cyclohexane-based organic chemicals used in electronic digital displays, and several of them possess bioaccumulative and toxic properties. Little is known about their occurrence in indoor dust from the United States. We analyzed 60 LCMs in 104 residential indoor dust samples collected from 16 states across the United States. Forty-seven of 60 LCMs were detected in dust samples at a median ∑LCM concentration of 402 ng/g (range: not detected to 4300 ng/g). Trans-4-propylcyclohexyl trans,trans-4'-propylbicyclohexyl-4-carboxylate (MPVBC) and (trans,trans)-4-fluorophenyl 4'-pentyl-[1,1'-bi(cyclohexane)]-4-carboxylate (FPeBC) were frequently detected in dust samples. We investigated potential sources of LCMs in dust by determining concentrations and profiles of these chemicals in smartphone screens, desktop and laptop computer monitors, and displays of other electronic devices and found that profiles in smartphones matched closely with those found in dust. The calculated median daily intake of ∑LCM through dust ingestion was 1.19 ng/kg bw/d for children, whereas that through dermal absorption was 0.18 ng/kg bw/d for adults in the United States.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-05Epub Date: 2024-06-15DOI: 10.1021/acs.joc.4c00310
Tongwei Liang, Qingjia Yuan, Li Xu, Jian-Quan Liu, Markus D Kärkäs, Xiang-Shan Wang
A silver-catalyzed protocol for the intermolecular radical umpolung cross-coupling protocol of silyl enol ethers with activated methylene compounds is disclosed. The protocol exhibits excellent functional group tolerance, enabling the expedient preparation of a variety of tricarbonyl compounds. Preliminary mechanistic investigations suggest that the reaction proceeds through a process involving free radicals in which silver oxide has a dual role, acting as both a catalyst and a base.
{"title":"Silver-Catalyzed Radical Umpolung Cross-Coupling of Silyl Enol Ethers with Activated Methylene Compounds: Access to Diverse Tricarbonyl Derivatives.","authors":"Tongwei Liang, Qingjia Yuan, Li Xu, Jian-Quan Liu, Markus D Kärkäs, Xiang-Shan Wang","doi":"10.1021/acs.joc.4c00310","DOIUrl":"10.1021/acs.joc.4c00310","url":null,"abstract":"<p><p>A silver-catalyzed protocol for the intermolecular radical umpolung cross-coupling protocol of silyl enol ethers with activated methylene compounds is disclosed. The protocol exhibits excellent functional group tolerance, enabling the expedient preparation of a variety of tricarbonyl compounds. Preliminary mechanistic investigations suggest that the reaction proceeds through a process involving free radicals in which silver oxide has a dual role, acting as both a catalyst and a base.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141326968","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}
Pub Date : 2024-07-05Epub Date: 2024-06-20DOI: 10.1021/acs.joc.4c00399
Yugandhar Kothapalli, Chung K Chu, Uma S Singh
β-l-5-((E)-2-Bromovinyl)-1-((2S,4S)-2-(hydroxymethyl)-1,3-(dioxolane-4-yl) uracil (l-BHDU, 17) is a potent and selective inhibitor of the varicella-zoster virus (VZV). l-BHDU (17) has demonstrated excellent anti-VZV activity and is a preclinical candidate to treat chickenpox, shingles (herpes zoster), and herpes simplex virus 1 (HSV-1) infections. Its monophosphate prodrug (POM-l-BHDU-MP, 24) demonstrated an enhanced pharmacokinetic and antiviral profile. POM-l-BHDU-MP (24), in vivo, effectively reduced the VZV viral load and was effective for the topical treatment of VZV and HSV-1 infections. Therefore, a viable synthetic procedure for developing POM-l-BHDU-MP (24) is needed. In this article, an efficient approach for the synthesis of l-BHDU (17) from a readily available starting material is described in 7 steps. An efficient and practical methodology for both chiral pure l- & d-dioxolane 11 and 13 were developed via diastereomeric chiral amine salt formation. Neutralization of the amine carboxylate salt of l-dioxolane 10 provides enantiomerically pure l-dioxane 11 (ee ≥ 99%). Optically pure 11 was utilized to construct the final nucleoside l-BHDU (17) and its monophosphate ester prodrug (POM-l-BHDU-MP, 24). Notably, the reported process eliminates expensive chiral chromatography for the synthesis of chiral pure l- & d-dioxolane, which offers avenues for the development and structure-activity relationship studies of l- & d-dioxolane-derived nucleosides.
{"title":"Enantioselective Synthesis of β-l-5-[(<i>E</i>)-2-Bromovinyl)-1-((2<i>S</i>,4<i>S</i>)-2-(hydroxymethyl)-1,3-(dioxolane-4-yl) Uracil)] (l-BHDU) <i>via</i> Chiral Pure l-Dioxolane.","authors":"Yugandhar Kothapalli, Chung K Chu, Uma S Singh","doi":"10.1021/acs.joc.4c00399","DOIUrl":"10.1021/acs.joc.4c00399","url":null,"abstract":"<p><p>β-l-5-((<i>E</i>)-2-Bromovinyl)-1-((2<i>S</i>,4<i>S</i>)-2-(hydroxymethyl)-1,3-(dioxolane-4-yl) uracil (l-BHDU, <b>17</b>) is a potent and selective inhibitor of the varicella-zoster virus (VZV). l-BHDU (<b>17</b>) has demonstrated excellent <i>anti</i>-VZV activity and is a preclinical candidate to treat chickenpox, shingles (herpes zoster), and herpes simplex virus 1 (HSV-1) infections. Its monophosphate prodrug (POM-l-BHDU-MP, <b>24</b>) demonstrated an enhanced pharmacokinetic and antiviral profile. POM-l-BHDU-MP (<b>24</b>), <i>in vivo</i>, effectively reduced the VZV viral load and was effective for the topical treatment of VZV and HSV-1 infections. Therefore, a viable synthetic procedure for developing POM-l-BHDU-MP (<b>24</b>) is needed. In this article, an efficient approach for the synthesis of l-BHDU (<b>17</b>) from a readily available starting material is described in 7 steps. An efficient and practical methodology for both chiral pure l- & d-dioxolane <b>11</b> and <b>13</b> were developed <i>via</i> diastereomeric chiral amine salt formation. Neutralization of the amine carboxylate salt of l-dioxolane <b>10</b> provides enantiomerically pure l-dioxane <b>11</b> (ee ≥ 99%). Optically pure <b>11</b> was utilized to construct the final nucleoside l-BHDU (<b>17</b>) and its monophosphate ester prodrug (POM-l-BHDU-MP, <b>24</b>). Notably, the reported process eliminates expensive chiral chromatography for the synthesis of chiral pure l- & d-dioxolane, which offers avenues for the development and structure-activity relationship studies of l- & d-dioxolane-derived nucleosides.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141430954","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}
Pub Date : 2024-07-05Epub Date: 2024-06-12DOI: 10.1021/acs.joc.4c00652
Stephen Hanessian
A retrospective is presented highlighting the synthesis of selected "first-in-kind" natural products, their synthetic analogues, structure elucidations, and rationally designed bioactive synthetic compounds that were accomplished because of collaborations with past and present pharmaceutical and agrochemical companies. Medicinal chemistry projects involving structure-based design exploiting cocrystal structures of small molecules with biologically relevant enzymes, receptors, and bacterial ribosomes with synthetic small molecules leading to marketed products, clinical candidates, and novel drug prototypes were realized in collaboration. Personal reflections, historical insights, behind the scenes stories from various long-term projects are shared in this retrospective article.
{"title":"My 50-Plus Years of Academic Research Collaborations with Industry. A Retrospective.","authors":"Stephen Hanessian","doi":"10.1021/acs.joc.4c00652","DOIUrl":"10.1021/acs.joc.4c00652","url":null,"abstract":"<p><p>A retrospective is presented highlighting the synthesis of selected \"first-in-kind\" natural products, their synthetic analogues, structure elucidations, and rationally designed bioactive synthetic compounds that were accomplished because of collaborations with past and present pharmaceutical and agrochemical companies. Medicinal chemistry projects involving structure-based design exploiting cocrystal structures of small molecules with biologically relevant enzymes, receptors, and bacterial ribosomes with synthetic small molecules leading to marketed products, clinical candidates, and novel drug prototypes were realized in collaboration. Personal reflections, historical insights, behind the scenes stories from various long-term projects are shared in this retrospective article.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141304881","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}
Pub Date : 2024-07-05Epub Date: 2024-06-12DOI: 10.1021/acs.joc.3c02769
Sini K S, Arun S, Shinu V S
A novel and efficient fragment-based assembly of symmetrical bis-peptidotraizoles has been developed based on double Sharpless azide-alkyne click chemistry. A new Cu(II) catalyzed protocol with a wide substrate scope was developed for accessing the symmetrical alkylidene bis-azidoamide fragment that yields the products in very good yields at room temperature without employing column purifications. The propargylated β-acetamido ketone fragment was accessed using another Cu(II) catalyzed room temperature MCR protocol. A fast double-click reaction (2 h) of symmetrical alkylidene bis-azidoamides with propargylated β-acetamido ketone fragments leads to the formation of unusual symmetrical bis-peptidotriazoles.
{"title":"Fragment-Based Design and Synthesis of Symmetrical <i>bis</i>-Peptidotriazoles Using Alkylidene <i>bis</i>-Amide Formations and Subsequent Triazole Ligation with β-Acetamido Carbonyl Scaffolds.","authors":"Sini K S, Arun S, Shinu V S","doi":"10.1021/acs.joc.3c02769","DOIUrl":"10.1021/acs.joc.3c02769","url":null,"abstract":"<p><p>A novel and efficient fragment-based assembly of symmetrical <i>bis</i>-peptidotraizoles has been developed based on double Sharpless azide-alkyne click chemistry. A new Cu(II) catalyzed protocol with a wide substrate scope was developed for accessing the symmetrical alkylidene <i>bis-</i>azidoamide fragment that yields the products in very good yields at room temperature without employing column purifications. The propargylated β-acetamido ketone fragment was accessed using another Cu(II) catalyzed room temperature MCR protocol. A fast double-click reaction (2 h) of symmetrical alkylidene <i>bis-</i>azidoamides with propargylated β-acetamido ketone fragments leads to the formation of unusual symmetrical <i>bis</i>-peptidotriazoles.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141309639","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}
Pub Date : 2024-07-05Epub Date: 2024-06-14DOI: 10.1021/acs.joc.4c00937
Hong-Tao Ji, Hai-Yang Song, Jia-Cheng Hou, Yao-Dan Xu, Li-Na Zeng, Wei-Min He
A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.
在室温、无添加剂和温和的条件下,使用 Z 型 V2O5/g-C3N4 异质结作为可循环光催化剂,在惰性气氛中建立了可见光引发的喹喔啉-2(1H)-酮的 C-H 三氟甲基化反应。研究人员以中等到较高的产率异构生成了多种三氟甲基化喹喔啉-2-(1H)-酮衍生物,并表现出良好的官能团耐受性。值得注意的是,可回收的 V2O5/g-C3N4 催化剂可重复使用五次,催化活性略有下降。
{"title":"Recyclable V<sub>2</sub>O<sub>5</sub>/g-C<sub>3</sub>N<sub>4</sub> Heterojunction-Catalyzed Visible-Light-Promoted C3-H Trifluoromethylation of Quinoxalin-2-(1<i>H</i>)-ones.","authors":"Hong-Tao Ji, Hai-Yang Song, Jia-Cheng Hou, Yao-Dan Xu, Li-Na Zeng, Wei-Min He","doi":"10.1021/acs.joc.4c00937","DOIUrl":"10.1021/acs.joc.4c00937","url":null,"abstract":"<p><p>A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1<i>H</i>)-ones was established using a Z-scheme V<sub>2</sub>O<sub>5</sub>/g-C<sub>3</sub>N<sub>4</sub> heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1<i>H</i>)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V<sub>2</sub>O<sub>5</sub>/g-C<sub>3</sub>N<sub>4</sub> catalyst could be reused five times with a slight loss of catalytic activity.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141316023","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}