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Porey A, Fremin SO, Nand S, Trevino R, Hughes WB, Dhakal SK, Nguyen VD, Greco SG, Arman HD, Larionov OV. Multimodal Acridine Photocatalysis Enables Direct Access to Thiols from Carboxylic Acids and Elemental Sulfur. ACS Catal 2024; 14:6973-6980. [PMID: 38737399 PMCID: PMC11081195 DOI: 10.1021/acscatal.4c01289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Development of photocatalytic systems that facilitate mechanistically divergent steps in complex catalytic manifolds by distinct activation modes can enable previously inaccessible synthetic transformations. However, multimodal photocatalytic systems remain understudied, impeding their implementation in catalytic methodology. We report herein a photocatalytic access to thiols that directly merges the structural diversity of carboxylic acids with the ready availability of elemental sulfur without substrate preactivation. The photocatalytic transformation provides a direct radical-mediated segue to one of the most biologically important and synthetically versatile organosulfur functionalities, whose synthetic accessibility remains largely dominated by two-electron-mediated processes based on toxic and uneconomical reagents and precursors. The two-phase radical process is facilitated by a multimodal catalytic reactivity of acridine photocatalysis that enables both the singlet excited state PCET-mediated decarboxylative carbon-sulfur bond formation and the previously unknown radical reductive disulfur bond cleavage by a photoinduced HAT process in the silane-triplet acridine system. The study points to a significant potential of multimodal photocatalytic systems in providing unexplored directions to previously inaccessible transformations.
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Affiliation(s)
- Arka Porey
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Seth O Fremin
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Sachchida Nand
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Ramon Trevino
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - William B Hughes
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Shree Krishna Dhakal
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Samuel G Greco
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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Dang HT, Nguyen VD, Haug GC, Arman HD, Larionov OV. Decarboxylative Triazolation Enables Direct Construction of Triazoles from Carboxylic Acids. JACS Au 2023; 3:813-822. [PMID: 37006773 PMCID: PMC10052276 DOI: 10.1021/jacsau.2c00606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 06/19/2023]
Abstract
Triazoles have major roles in chemistry, medicine, and materials science, as centrally important heterocyclic motifs and bioisosteric replacements for amides, carboxylic acids, and other carbonyl groups, as well as some of the most widely used linkers in click chemistry. Yet, the chemical space and molecular diversity of triazoles remains limited by the accessibility of synthetically challenging organoazides, thereby requiring preinstallation of the azide precursors and restricting triazole applications. We report herein a photocatalytic, tricomponent decarboxylative triazolation reaction that for the first time enables direct conversion of carboxylic acids to triazoles in a single-step, triple catalytic coupling with alkynes and a simple azide reagent. Data-guided inquiry of the accessible chemical space of decarboxylative triazolation indicates that the transformation can improve access to the structural diversity and molecular complexity of triazoles. Experimental studies demonstrate a broad scope of the synthetic method that includes a variety of carboxylic acid, polymer, and peptide substrates. When performed in the absence of alkynes, the reaction can also be used to access organoazides, thereby obviating preactivation and specialized azide reagents and providing a two-pronged approach to C-N bond-forming decarboxylative functional group interconversions.
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Nguyen VD, Haug GC, Greco SG, Trevino R, Karki GB, Arman HD, Larionov OV. Decarboxylative Sulfinylation Enables a Direct, Metal-Free Access to Sulfoxides from Carboxylic Acids. Angew Chem Int Ed Engl 2022; 61:e202210525. [PMID: 36006859 PMCID: PMC9588746 DOI: 10.1002/anie.202210525] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Indexed: 12/14/2022]
Abstract
The intermediate oxidation state of sulfoxides is central to the plethora of their applications in chemistry and medicine, yet it presents challenges for an efficient synthetic access, limiting the structural diversity of currently available sulfoxides. Here, we report a data-guided development of direct decarboxylative sulfinylation that enables the previously inaccessible functional group interconversion of carboxylic acids to sulfoxides in a reaction with sulfinates. Given the broad availability of carboxylic acids and the growing synthetic potential of sulfinates, the direct decarboxylative sulfinylation is poised to improve the structural diversity of synthetically accessible sulfoxides. The reaction is facilitated by a kinetically favored sulfoxide formation from the intermediate sulfinyl sulfones, despite the strong thermodynamic preference for the sulfone formation, unveiling the previously unknown and chemoselective radicalophilic sulfinyl sulfone reactivity.
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Affiliation(s)
- Viet D Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Graham C Haug
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Samuel G Greco
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Ramon Trevino
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Guna B Karki
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Hadi D Arman
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Oleg V Larionov
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
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Nguyen VD, Haug GC, Greco SG, Trevino R, Karki GB, Arman HD, Larionov OV. Titelbild: Decarboxylative Sulfinylation Enables a Direct, Metal‐Free Access to Sulfoxides from Carboxylic Acids (Angew. Chem. 43/2022). Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202284341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Viet D. Nguyen
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Graham C. Haug
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Samuel G. Greco
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Ramon Trevino
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Guna B. Karki
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Hadi D. Arman
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Oleg V. Larionov
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
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Nguyen VD, Haug GC, Greco SG, Trevino R, Karki GB, Arman HD, Larionov OV. Cover Picture: Decarboxylative Sulfinylation Enables a Direct, Metal‐Free Access to Sulfoxides from Carboxylic Acids (Angew. Chem. Int. Ed. 43/2022). Angew Chem Int Ed Engl 2022. [DOI: 10.1002/anie.202284341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Viet D. Nguyen
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Graham C. Haug
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Samuel G. Greco
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Ramon Trevino
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Guna B. Karki
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Hadi D. Arman
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Oleg V. Larionov
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
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Nguyen VD, Haug GC, Greco SG, Trevino R, Karki GB, Arman HD, Larionov OV. Decarboxylative Sulfinylation Enables a Direct, Metal‐Free Access to Sulfoxides from Carboxylic Acids. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202214350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Viet D. Nguyen
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Graham C. Haug
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Samuel G. Greco
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Ramon Trevino
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Guna B. Karki
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Hadi D. Arman
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
| | - Oleg V. Larionov
- Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX, 78249 USA
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Nguyen VD, Haug GC, Greco SG, Trevino R, Karki GB, Arman HD, Larionov O. Decarboxylative Sulfinylation Enables a Direct, Metal‐Free Access to Sulfoxides from Carboxylic Acids. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Viet D. Nguyen
- The University of Texas at San Antonio Department of Chemistry 78249 San Antonio UNITED STATES
| | - Graham C. Haug
- The University of Texas at San Antonio Deoartment of Chemistry 1 utsa circle 78249 SAN ANTONIO UNITED STATES
| | - Samuel G. Greco
- The University of Texas at San Antonio Department of Chemistry UNITED STATES
| | - Ramon Trevino
- The University of Texas at San Antonio Department of Chemistry UNITED STATES
| | - Guna B. Karki
- The University of Texas at San Antonio Department of Chemistry UNITED STATES
| | - Hadi D. Arman
- The University of Texas at San Antonio Department of Chemistry UNITED STATES
| | - Oleg Larionov
- University of Texas at San Antonio Department of Chemistry One UTSA Circle 78249 San Antonio UNITED STATES
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Nguyen VD, Trevino R, Greco SG, Arman HD, Larionov OV. Tricomponent Decarboxysulfonylative Cross-Coupling Facilitates Direct Construction of Aryl Sulfones and Reveals a Mechanistic Dualism in the Acridine/Copper Photocatalytic System. ACS Catal 2022; 12:8729-8739. [PMID: 36643936 PMCID: PMC9833479 DOI: 10.1021/acscatal.2c02332] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Dual catalytic systems involving photocatalytic activation and transition metal-catalyzed steps have enabled innovative approaches to the construction of carbon-carbon and carbon-heteroatom bonds. However, the mechanistic complexity of the dual catalytic processes presents multiple challenges for understanding of the roles of divergent catalytic species that can impede the development of future synthetic methods. Here, we report a dual catalytic process that enables the previously inaccessible, broad-scope, direct conversion of carboxylic acids to aromatic sulfones-centrally important carbonyl group bioisosteric replacements and synthetic intermediates-by a tricomponent decarboxysulfonylative cross-coupling with aryl halides. Detailed mechanistic and computational studies revealed the roles of the copper catalyst, base, and halide anions in channeling the acridine/copper system via a distinct dual catalytic manifold. In contrast to the halide-free decarboxylative conjugate addition that involves cooperative dual catalysis via low-valent copper species, the halide counteranions divert the decarboxysulfonylative cross-coupling with aryl halides through a two-phase, orthogonal relay catalytic manifold, comprising a kinetically coupled (via antithetical inhibitory and activating roles of the base in the two catalytic cycles), mechanistically discrete sequence of a photoinduced, acridine-catalyzed decarboxylative process and a thermal copper-catalyzed arylative coupling. The study underscores the importance of non-innocent roles of counteranions and key redox steps at the interface of catalytic cycles for enabling previously inaccessible dual catalytic transformations.
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Affiliation(s)
- Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Ramon Trevino
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Samuel G. Greco
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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Travis BA, Peck JV, Salinas R, Dopkins B, Lent N, Nguyen VD, Borgnia MJ, Brennan RG, Schumacher MA. Molecular dissection of the glutamine synthetase-GlnR nitrogen regulatory circuitry in Gram-positive bacteria. Nat Commun 2022; 13:3793. [PMID: 35778410 PMCID: PMC9249791 DOI: 10.1038/s41467-022-31573-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 06/21/2022] [Indexed: 11/23/2022] Open
Abstract
How bacteria sense and respond to nitrogen levels are central questions in microbial physiology. In Gram-positive bacteria, nitrogen homeostasis is controlled by an operon encoding glutamine synthetase (GS), a dodecameric machine that assimilates ammonium into glutamine, and the GlnR repressor. GlnR detects nitrogen excess indirectly by binding glutamine-feedback-inhibited-GS (FBI-GS), which activates its transcription-repression function. The molecular mechanisms behind this regulatory circuitry, however, are unknown. Here we describe biochemical and structural analyses of GS and FBI-GS-GlnR complexes from pathogenic and non-pathogenic Gram-positive bacteria. The structures show FBI-GS binds the GlnR C-terminal domain within its active-site cavity, juxtaposing two GlnR monomers to form a DNA-binding-competent GlnR dimer. The FBI-GS-GlnR interaction stabilizes the inactive GS conformation. Strikingly, this interaction also favors a remarkable dodecamer to tetradecamer transition in some GS, breaking the paradigm that all bacterial GS are dodecamers. These data thus unveil unique structural mechanisms of transcription and enzymatic regulation.
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Affiliation(s)
- Brady A Travis
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Jared V Peck
- Cryo-EM core, Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC, 27514, USA
| | - Raul Salinas
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Brandon Dopkins
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Nicholas Lent
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Viet D Nguyen
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Mario J Borgnia
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, USA
| | - Richard G Brennan
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA
| | - Maria A Schumacher
- Department of Biochemistry, 307 Research Dr., Box 3711, Duke University Medical Center, Durham, NC, 27710, USA.
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Gozzi K, Salinas R, Nguyen VD, Laub MT, Schumacher MA. ssDNA is an allosteric regulator of the C. crescentus SOS-independent DNA damage response transcription activator, DriD. Genes Dev 2022; 36:618-633. [PMID: 35618312 PMCID: PMC9186387 DOI: 10.1101/gad.349541.122] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/12/2022] [Indexed: 12/18/2022]
Abstract
DNA damage repair systems are critical for genomic integrity. However, they must be coordinated with DNA replication and cell division to ensure accurate genomic transmission. In most bacteria, this coordination is mediated by the SOS response through LexA, which triggers a halt in cell division until repair is completed. Recently, an SOS-independent damage response system was revealed in Caulobacter crescentus. This pathway is controlled by the transcription activator, DriD, but how DriD senses and signals DNA damage is unknown. To address this question, we performed biochemical, cellular, and structural studies. We show that DriD binds a specific promoter DNA site via its N-terminal HTH domain to activate transcription of genes, including the cell division inhibitor didA A structure of the C-terminal portion of DriD revealed a WYL motif domain linked to a WCX dimerization domain. Strikingly, we found that DriD binds ssDNA between the WYL and WCX domains. Comparison of apo and ssDNA-bound DriD structures reveals that ssDNA binding orders and orients the DriD domains, indicating a mechanism for ssDNA-mediated operator DNA binding activation. Biochemical and in vivo studies support the structural model. Our data thus reveal the molecular mechanism underpinning an SOS-independent DNA damage repair pathway.
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Affiliation(s)
- Kevin Gozzi
- Department of Biology, Massachusetts Institute of Technology. Cambridge, Massachusetts 02139, USA
| | - Raul Salinas
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Viet D Nguyen
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Michael T Laub
- Department of Biology, Massachusetts Institute of Technology. Cambridge, Massachusetts 02139, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Maria A Schumacher
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
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Nguyen VT, Haug GC, Nguyen VD, Vuong NTH, Karki GB, Arman HD, Larionov OV. Functional group divergence and the structural basis of acridine photocatalysis revealed by direct decarboxysulfonylation. Chem Sci 2022; 13:4170-4179. [PMID: 35440976 PMCID: PMC8985579 DOI: 10.1039/d2sc00789d] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 03/21/2022] [Indexed: 02/03/2023] Open
Abstract
The reactivity of the sulfonyl group varies dramatically from nucleophilic sulfinates through chemically robust sulfones to electrophilic sulfonyl halides-a feature that has been used extensively in medicinal chemistry, synthesis, and materials science, especially as bioisosteric replacements and structural analogs of carboxylic acids and other carbonyls. Despite the great synthetic potential of the carboxylic to sulfonyl functional group interconversions, a method that can convert carboxylic acids directly to sulfones, sulfinates and sulfonyl halides has remained out of reach. We report herein the development of a photocatalytic system that for the first time enables direct decarboxylative conversion of carboxylic acids to sulfones and sulfinates, as well as sulfonyl chlorides and fluorides in one step and in a multicomponent fashion. A mechanistic study prompted by the development of the new method revealed the key structural features of the acridine photocatalysts that facilitate the decarboxylative transformations and provided an informative and predictive multivariate linear regression model that quantitatively relates the structural features with the photocatalytic activity.
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Affiliation(s)
- Vu T Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Ngan T H Vuong
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Guna B Karki
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
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Sarić R, Nguyen VD, Burge T, Berkowitz O, Trtílek M, Whelan J, Lewsey MG, Čustović E. Applications of hyperspectral imaging in plant phenotyping. Trends Plant Sci 2022; 27:301-315. [PMID: 34998690 DOI: 10.1016/j.tplants.2021.12.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 11/30/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Our ability to interrogate and manipulate the genome far exceeds our capacity to measure the effects of genetic changes on plant traits. Much effort has been made recently by the plant science research community to address this imbalance. The responses of plants to environmental conditions can now be defined using a variety of imaging approaches. Hyperspectral imaging (HSI) has emerged as a promising approach to measure traits using a wide range of wavebands simultaneously in 3D to capture information in lab, glasshouse, or field settings. HSI has been applied to define abiotic, biotic, and quality traits for optimisation of crop management.
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Affiliation(s)
- Rijad Sarić
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia
| | - Viet D Nguyen
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia
| | - Timothy Burge
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Martin Trtílek
- Photon Systems Instruments plant phenotyping research centre, Photon System Instruments, 664 24 Drasov, Brno, Czech Republic
| | - James Whelan
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia.
| | - Mathew G Lewsey
- Department of Animal, Plant and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Edhem Čustović
- Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia
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13
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Nguyen VD, Sarić R, Burge T, Berkowitz O, Trtilek M, Whelan J, Lewsey MG, Čustović E. Noninvasive imaging technologies in plant phenotyping. Trends Plant Sci 2022; 27:316-317. [PMID: 34257004 DOI: 10.1016/j.tplants.2021.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/09/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Affiliation(s)
- Viet D Nguyen
- Department of Animal, Plant, and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Rijad Sarić
- Department of Animal, Plant, and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia
| | - Timothy Burge
- Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant, and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Martin Trtilek
- Photon Systems Instruments plant phenotyping research centre, Photon System Instruments, 664 24 Drasov, Brno, Czech Republic
| | - James Whelan
- Department of Animal, Plant, and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia.
| | - Mathew G Lewsey
- Department of Animal, Plant, and Soil Science, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia; Australian Research Council Research Hub for Medicinal Agriculture, AgriBio Building, La Trobe University, Bundoora, VIC 3086, Australia
| | - Edhem Čustović
- Department of Engineering, School of Engineering and Mathematical Sciences, La Trobe University, Bundoora, VIC 3086, Australia
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14
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Jin S, Sui X, Haug GC, Nguyen VD, Dang HT, Arman HD, Larionov OV. N-Heterocyclic Carbene-Photocatalyzed Tricomponent Regioselective 1,2-Diacylation of Alkenes Illuminates the Mechanistic Details of the Electron Donor–Acceptor Complex-Mediated Radical Relay Processes. ACS Catal 2021. [DOI: 10.1021/acscatal.1c04594] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Xianwei Sui
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Graham C. Haug
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hang T. Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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15
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Jin S, Haug GC, Trevino R, Nguyen VD, Arman HD, Larionov OV. Photoinduced C(sp 3)-H sulfination empowers the direct and chemoselective introduction of the sulfonyl group. Chem Sci 2021; 12:13914-13921. [PMID: 34760178 PMCID: PMC8549786 DOI: 10.1039/d1sc04245a] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/27/2021] [Indexed: 12/12/2022] Open
Abstract
Direct installation of the sulfinate group by the functionalization of unreactive aliphatic C-H bonds can provide access to most classes of organosulfur compounds, because of the central position of sulfinates as sulfonyl group linchpins. Despite the importance of the sulfonyl group in synthesis, medicine, and materials science, a direct C(sp3)-H sulfination reaction that can convert abundant aliphatic C-H bonds to sulfinates has remained elusive, due to the reactivity of sulfinates that are incompatible with typical oxidation-driven C-H functionalization approaches. We report herein a photoinduced C(sp3)-H sulfination reaction that is mediated by sodium metabisulfite and enables access to a variety of sulfinates. The reaction proceeds with high chemoselectivity and moderate to good regioselectivity, affording only monosulfination products and can be used for a solvent-controlled regiodivergent distal C(sp3)-H functionalization.
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Affiliation(s)
- Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Ramon Trevino
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
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16
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Nguyen VT, Haug GC, Nguyen VD, Vuong NTH, Arman HD, Larionov OV. Photocatalytic decarboxylative amidosulfonation enables direct transformation of carboxylic acids to sulfonamides. Chem Sci 2021; 12:6429-6436. [PMID: 34084443 PMCID: PMC8115300 DOI: 10.1039/d1sc01389k] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 04/06/2021] [Indexed: 11/21/2022] Open
Abstract
Sulfonamides feature prominently in organic synthesis, materials science and medicinal chemistry, where they play important roles as bioisosteric replacements of carboxylic acids and other carbonyls. Yet, a general synthetic platform for the direct conversion of carboxylic acids to a range of functionalized sulfonamides has remained elusive. Herein, we present a visible light-induced, dual catalytic platform that for the first time allows for a one-step access to sulfonamides and sulfonyl azides directly from carboxylic acids. The broad scope of the direct decarboxylative amidosulfonation (DDAS) platform is enabled by the efficient direct conversion of carboxylic acids to sulfinic acids that is catalyzed by acridine photocatalysts and interfaced with copper-catalyzed sulfur-nitrogen bond-forming cross-couplings with both electrophilic and nucleophilic reagents.
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Affiliation(s)
- Vu T Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Ngan T H Vuong
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
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17
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Dang HT, Nguyen VD, Haug GC, Vuong NTH, Arman HD, Larionov OV. Z-Selective Dienylation Enables Stereodivergent Construction of Dienes and Unravels a Ligand-Driven Mechanistic Dichotomy. ACS Catal 2021; 11:1042-1052. [PMID: 33968463 DOI: 10.1021/acscatal.0c05574] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Development of stereoselective and efficient reactions for construction of conjugated dienes and polyenes has remained at the forefront of organic chemistry, due to their key roles in medicinal chemistry, organic synthesis, and materials science. The synthesis of conjugated dienes and polyenes is typically accomplished in a multistep manner by sequential installation of individual C=C bonds because it allows for control of stereoselectivity and efficiency of formation of each double bond. A conceptually distinct dienylation approach entails a stereoselective appendage of a four-carbon unit, shortcutting diene synthesis. Dienylation with sulfolene provided a direct route to E-dienes, but the synthesis of substantially more challenging Z-dienes remained elusive. Here, we report that a highly Z-selective dienylation can be now achieved by a simple adjustment of a ligand, enabling stereodivergent synthesis of E- and Z-dienes from one reagent and in one step. A detailed mechanistic investigation of the E- and Z-selective dienylation provided insight into the divergent behavior of the two catalytic systems and revealed that differences in relative stabilities of catalytically active palladium phosphine complexes have a major impact on the stereochemical outcomes of the dienylation.
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Affiliation(s)
- Hang T. Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Graham C. Haug
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Ngan T. H. Vuong
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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18
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Llanes A, Cruz H, Nguyen VD, Larionov OV, Fernández PL. A Computational Approach to Explore the Interaction of Semisynthetic Nitrogenous Heterocyclic Compounds with the SARS-CoV-2 Main Protease. Biomolecules 2020; 11:biom11010018. [PMID: 33375460 PMCID: PMC7824519 DOI: 10.3390/biom11010018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 12/23/2022] Open
Abstract
In the context of the ongoing coronavirus disease 2019 (COVID-19) pandemic, numerous attempts have been made to discover new potential antiviral molecules against its causative agent, SARS-CoV-2, many of which focus on its main protease (Mpro). We hereby used two approaches based on molecular docking simulation to explore the interaction of four libraries of semisynthetic nitrogenous heterocyclic compounds with Mpro. Libraries L1 and L2 contain 52 synthetic derivatives of the natural compound 2-propylquinoline, whereas libraries L3 and L4 contain 65 compounds synthesized using the natural compound physostigmine as a precursor. Validation through redocking suggested that the rigid receptor and flexible receptor approaches used for docking were suitable to model the interaction of this type of compounds with the target protein, although the flexible approach seemed to provide a more realistic representation of interactions within the active site. Using empirical energy score thresholds, we selected 58 compounds from the four libraries with the most favorable energy estimates. Globally, favorable estimates were obtained for molecules with two or more substituents, putatively accommodating in three or more subsites within the Mpro active site. Our results pave the way for further experimental evaluation of the selected compounds as potential antiviral agents against SARS-CoV-2.
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Affiliation(s)
- Alejandro Llanes
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Ciudad del Saber, Panama 0801, Panama; (A.L.); (H.C.)
| | - Héctor Cruz
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Ciudad del Saber, Panama 0801, Panama; (A.L.); (H.C.)
| | - Viet D. Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA;
| | - Oleg V. Larionov
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA;
- Correspondence: (O.V.L.); (P.L.F.); Tel.: +1-(210)-458-6050 (O.V.L.); +(507)-517-0700 (P.L.F.)
| | - Patricia L. Fernández
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Ciudad del Saber, Panama 0801, Panama; (A.L.); (H.C.)
- Correspondence: (O.V.L.); (P.L.F.); Tel.: +1-(210)-458-6050 (O.V.L.); +(507)-517-0700 (P.L.F.)
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19
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Dang HT, Haug GC, Nguyen VT, Vuong NTH, Nguyen VD, Arman HD, Larionov OV. Acridine Photocatalysis: Insights into the Mechanism and Development of a Dual-Catalytic Direct Decarboxylative Conjugate Addition. ACS Catal 2020; 10:11448-11457. [PMID: 36636662 PMCID: PMC9833602 DOI: 10.1021/acscatal.0c03440] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Conjugate addition is one of the most synthetically useful carbon‒carbon bond-forming reactions, however, reactive carbon nucleophiles are typically required to effect the addition. Radical conjugate addition provides an avenue for replacing reactive nucleophiles with convenient radical precursors. Carboxylic acids can serve as simple and stable radical precursors by way of decarboxylation, but activation to reactive esters is typically necessary to facilitate the challenging decarboxylation. Here, we report a direct, dual-catalytic decarboxylative radical conjugate addition of a wide range of carboxylic acids that does not require acid preactivation and is enabled by the visible light-driven acridine photocatalysis interfaced with an efficient copper catalytic cycle. Mechanistic and computational studies provide insights into the roles of the ligands and metal species in the dual catalytic process and the photocatalytic activity of substituted acridines.
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Affiliation(s)
- Hang T. Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Graham C. Haug
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Vu T. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Ngan T. H. Vuong
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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20
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Boureau V, Nguyen VD, Masseboeuf A, Palomino A, Gautier E, Chatterjee J, Lequeux S, Auffret S, Vila L, Sousa R, Prejbeanu L, Cooper D, Dieny B. An electron holography study of perpendicular magnetic tunnel junctions nanostructured by deposition on pre-patterned conducting pillars. Nanoscale 2020; 12:17312-17318. [PMID: 32789322 DOI: 10.1039/d0nr03353g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The fabrication of multi-gigabit magnetic random access memory (MRAM) chips requires the patterning of magnetic tunnel junctions at very small dimensions (sub-30 nm) and a very dense pitch. This remains a challenge due to the difficulty in etching magnetic tunnel junction stacks. We previously proposed a strategy to circumvent this problem by depositing the magnetic tunnel junction material on prepatterned metallic pillars, resulting in the junction being naturally shaped during deposition. Upon electrical contact, the deposit on top of the pillars constitutes the magnetic storage element of the memory cell. However, in this process, the magnetic material is also deposited in the trenches between the pillars that might affect the memory cell behaviour. Here we study the magnetic interactions between the deposit on top of the pillars and in the trenches by electron holography, at room temperature and up to 325 °C. Supported by models, we show that the additional material in the trenches is not perturbing the working principle of the memory chip and can even play the role of a flux absorber which reduces the crosstalk between neighboring dots. Besides, in the studied sample, the magnetization of the 1.4 nm thick storage layer of the dots is found to switch from out-of-plane to an in-plane configuration above 125 °C, but gradually decreases with temperature. Electron holography is shown to constitute a very efficient tool for characterizing the micromagnetic configuration of the storage layer in MRAM cells.
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Affiliation(s)
- V Boureau
- Univ. Grenoble Alpes, CEA-LETI, F-38000 Grenoble, France.
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21
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Jin S, Dang HT, Haug GC, Nguyen VD, Arman HD, Larionov OV. Deoxygenative α-alkylation and α-arylation of 1,2-dicarbonyls. Chem Sci 2020; 11:9101-9108. [PMID: 34094191 PMCID: PMC8161533 DOI: 10.1039/d0sc03118f] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 06/30/2020] [Indexed: 01/26/2023] Open
Abstract
Construction of C-C bonds at the α-carbon is a challenging but synthetically indispensable approach to α-branched carbonyl motifs that are widely represented among drugs, natural products, and synthetic intermediates. Here, we describe a simple approach to generation of boron enolates in the absence of strong bases that allows for introduction of both α-alkyl and α-aryl groups in a reaction of readily accessible 1,2-dicarbonyls and organoboranes. Obviation of unselective, strongly basic and nucleophilic reagents permits carrying out the reaction in the presence of electrophiles that intercept the intermediate boron enolates, resulting in two new α-C-C bonds in a tricomponent process.
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Affiliation(s)
- Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
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22
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Nguyen VT, Nguyen VD, Haug GC, Vuong NTH, Dang HT, Arman HD, Larionov OV. Visible-Light-Enabled Direct Decarboxylative N-Alkylation. Angew Chem Int Ed Engl 2020; 59:7921-7927. [PMID: 32050048 PMCID: PMC7200280 DOI: 10.1002/anie.201916710] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Indexed: 11/12/2022]
Abstract
The development of efficient and selective C-N bond-forming reactions from abundant feedstock chemicals remains a central theme in organic chemistry owing to the key roles of amines in synthesis, drug discovery, and materials science. Herein, we present a dual catalytic system for the N-alkylation of diverse aromatic carbocyclic and heterocyclic amines directly with carboxylic acids, by-passing their preactivation as redox-active esters. The reaction, which is enabled by visible-light-driven, acridine-catalyzed decarboxylation, provides access to N-alkylated secondary and tertiary anilines and N-heterocycles. Additional examples, including double alkylation, the installation of metabolically robust deuterated methyl groups, and tandem ring formation, further demonstrate the potential of the direct decarboxylative alkylation (DDA) reaction.
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Affiliation(s)
- Vu T Nguyen
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Ngan T H Vuong
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
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23
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Nguyen VT, Nguyen VD, Haug GC, Vuong NTH, Dang HT, Arman HD, Larionov OV. Visible‐Light‐Enabled Direct Decarboxylative N‐Alkylation. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201916710] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Vu T. Nguyen
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D. Nguyen
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C. Haug
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Ngan T. H. Vuong
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hang T. Dang
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D. Arman
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V. Larionov
- Department of Chemistry The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
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24
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Jin S, Dang HT, Haug GC, He R, Nguyen VD, Nguyen VT, Arman HD, Schanze KS, Larionov OV. Visible Light-Induced Borylation of C-O, C-N, and C-X Bonds. J Am Chem Soc 2020; 142:1603-1613. [PMID: 31899630 PMCID: PMC7137638 DOI: 10.1021/jacs.9b12519] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Boronic acids are centrally important functional motifs and synthetic precursors. Visible light-induced borylation may provide access to structurally diverse boronates, but a broadly efficient photocatalytic borylation method that can effect borylation of a wide range of substrates, including strong C-O bonds, remains elusive. Herein, we report a general, metal-free visible light-induced photocatalytic borylation platform that enables borylation of electron-rich derivatives of phenols and anilines, chloroarenes, as well as other haloarenes. The reaction exhibits excellent functional group tolerance, as demonstrated by the borylation of a range of structurally complex substrates. Remarkably, the reaction is catalyzed by phenothiazine, a simple organic photocatalyst with MW < 200 that mediates the previously unachievable visible light-induced single electron reduction of phenol derivatives with reduction potentials as negative as approximately - 3 V versus SCE by a proton-coupled electron transfer mechanism. Mechanistic studies point to the crucial role of the photocatalyst-base interaction.
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Affiliation(s)
- Shengfei Jin
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Hang T Dang
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Graham C Haug
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Ru He
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
- Department of Chemistry , University of Florida , Gainesville , Florida 32611 , United States
| | - Viet D Nguyen
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Vu T Nguyen
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Hadi D Arman
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Kirk S Schanze
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Oleg V Larionov
- Department of Chemistry , University of Texas at San Antonio , San Antonio , Texas 78249 , United States
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25
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Roytman VA, Jin S, Nguyen VT, Nguyen VD, Haug GC, Larionov OV, Singleton DA. Bond Memory in Dynamically Determined Stereoselectivity. J Am Chem Soc 2019; 142:85-88. [PMID: 31852185 DOI: 10.1021/jacs.9b12227] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The carboborative ring contraction of cyclohexenes exhibits an abnormal selectivity pattern in which a formally concerted double migration gives rise to predominant but not exclusive inversion products. In dynamic trajectories, the inversion and retention products are formed from the same transition state, and the trajectories accurately account for the experimental product ratios. The unusual origin of the selectivity is the dynamically retained non-equivalence of newly formed versus pre-existing bonds after the first bond migration.
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Affiliation(s)
- Vladislav A Roytman
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842 , United States
| | - Shengfei Jin
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Vu T Nguyen
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Viet D Nguyen
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Graham C Haug
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Oleg V Larionov
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Daniel A Singleton
- Department of Chemistry , Texas A&M University , P.O. Box 30012, College Station , Texas 77842 , United States
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26
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Doens D, Valdés-Tresanco ME, Vasquez V, Carreira MB, De La Guardia Y, Stephens DE, Nguyen VD, Nguyen VT, Gu J, Hegde ML, Larionov OV, Valiente PA, Lleonart R, Fernández PL. Hexahydropyrrolo[2,3- b]indole Compounds as Potential Therapeutics for Alzheimer's Disease. ACS Chem Neurosci 2019; 10:4250-4263. [PMID: 31545596 DOI: 10.1021/acschemneuro.9b00297] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia among the elderly and has become a leading public health concern worldwide. It represents a huge economic and psychological burden to caregivers and families. The presence of extracellular amyloid beta (Aβ) plaques is one of the hallmarks of this neurodegenerative disorder. Amyloid plaques are comprised of aggregates of Aβ peptides, mainly Aβ42, originated by the cleavage of the amyloid precursor protein (APP). Aβ is a crucial target for the treatment of AD, but to date, no effective treatment for the clearance of Aβ has been found. We have identified four new hexahydropyrroloindoles (HPI) synthetic compounds that are able to inhibit the aggregation of Aβ42 and/or disaggregate the fibril. Docking experiments suggest that the nonpolar component of the interaction of compounds with Aβ42 contributes favorably to the binding free energy of each complex. Molecular dynamics simulations suggested fibril disaggregating activity of compounds 1 via interaction with hydrophobic moieties of the fibril. Consistently, compounds 1 and 2 were able to mitigate Aβ42 fibrils induced death in rat pheochromocytoma cells (PC 12). One of the compounds reduces the formation of Aβ aggregates in vivo and the paralysis associated with Aβ toxicity in Caenorhabditis elegans. Our study thus augments efforts for the identification and characterization of new agents that may help stop or delay the progression of AD.
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Affiliation(s)
- Deborah Doens
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh 522510, India
| | - Mario E. Valdés-Tresanco
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Calle 25 No. 455, Vedado, La Habana, Cuba
| | - Velmarini Vasquez
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh 522510, India
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Maria Beatriz Carreira
- Centro de Neurociencias, INDICASAT-AIP, City of Knowledge Edif #208, Panama, 0843-01103, Panama
| | - Yila De La Guardia
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
| | - David E. Stephens
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Vu T. Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Jianhua Gu
- AFM SEM Core, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Muralidhar L. Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Oleg V. Larionov
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Pedro A. Valiente
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Calle 25 No. 455, Vedado, La Habana, Cuba
| | - Ricardo Lleonart
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
| | - Patricia L. Fernández
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
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Nguyen VT, Nguyen VD, Haug GC, Dang HT, Jin S, Li Z, Flores-Hansen C, Benavides BS, Arman HD, Larionov OV. Alkene Synthesis by Photocatalytic Chemoenzymatically Compatible Dehydrodecarboxylation of Carboxylic Acids and Biomass. ACS Catal 2019; 9:9485-9498. [PMID: 35223139 DOI: 10.1021/acscatal.9b02951] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Direct conversion of renewable biomass and bioderived chemicals to valuable synthetic intermediates for organic synthesis and materials science applications by means of mild and chemoselective catalytic methods has largely remained elusive. Development of artificial catalytic systems that are compatible with enzymatic reactions provides a synergistic solution to this enduring challenge by leveraging previously unachievable reactivity and selectivity modes. We report herein a dual catalytic dehydrodecarboxylation reaction that is enabled by a crossover of the photoinduced acridine-catalyzed O-H hydrogen atom transfer (HAT) and cobaloxime-catalyzed C-H-HAT processes. The reaction produces a variety of alkenes from readily available carboxylic acids. The reaction can be embedded in a scalable triple-catalytic cooperative chemoenzymatic lipase-acridine-cobaloxime process that allows for direct conversion of plant oils and biomass to long-chain terminal alkenes, precursors to bioderived polymers.
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Affiliation(s)
- Vu T. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Graham C. Haug
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hang T. Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Zhiliang Li
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Carsten Flores-Hansen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Brenda S. Benavides
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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Dang HT, Nguyen VD, Pham HH, Arman HD, Larionov OV. Highly Stereoselective and Catalytic Desulfitative C-O and C-I Dienylation with Sulfolenes: the Importance of Basic Additives. Tetrahedron 2019; 75:3258-3264. [PMID: 31885406 DOI: 10.1016/j.tet.2019.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Conjugated dienes and polyenes are central structural motifs of natural products, and key synthetic intermediates in organic synthesis and materials science. We describe herein a palladium-catalyzed dienylation of aryl, heteroaryl, and vinyl triflates, nonaflates and iodides that were previously identified as recalcitrant substrates for the sulfolene-mediated catalytic dienylation. The method has now been successfully expanded to C-O and C-I dienylation, demonstrating broad scope with respect to sulfonates, iodides and sulfolenes. The reactions proceed with high regio- and stereoselectivity, and efficiency that are strongly influenced by basic additives, whose influence on the reaction performance was systematically studied.
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Affiliation(s)
- Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, United States
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, United States
| | - Hoang H Pham
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, United States
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, United States
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, United States
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29
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Nguyen VD, Nguyen VT, Haug GC, Dang HT, Arman HD, Ermler WC, Larionov OV. Rapid and Chemodivergent Synthesis of N-Heterocyclic Sulfones and Sulfides: Mechanistic and Computational Details of the Persulfate-Initiated Catalysis. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00464] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Viet D. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Vu T. Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Graham C. Haug
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hang T. Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Walter C. Ermler
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Oleg V. Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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30
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Dang HT, Nguyen VT, Nguyen VD, Arman HD, Larionov OV. Efficient synthesis of 3-sulfolenes from allylic alcohols and 1,3-dienes enabled by sodium metabisulfite as a sulfur dioxide equivalent. Org Biomol Chem 2019; 16:3605-3609. [PMID: 29701220 DOI: 10.1039/c8ob00745d] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present herein an efficient and practical method for a gram scale synthesis of 3-sulfolenes using sodium metabisulfite as a safe, inexpensive, and easy to handle sulfur dioxide equivalent. Diversely-substituted 3-sulfolenes can be prepared by reacting a variety of 1,3-dienes or allylic alcohols with sodium metabisulfite in aqueous hexafluoroisopropanol (HFIP) or in aqueous methanol in the presence of potassium hydrogen sulfate. Advantageously, the method enables conversion of allylic alcohols directly to 3-sulfolenes, bypassing intermediate 1,3-dienes.
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Affiliation(s)
- Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, USA.
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31
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Nguyen VD, Nguyen VT, Jin S, Dang HT, Larionov OV. Organoboron chemistry comes to light: recent advances in photoinduced synthetic approaches to organoboron compounds. Tetrahedron 2019; 75:584-602. [PMID: 31564756 PMCID: PMC6764765 DOI: 10.1016/j.tet.2018.12.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Photoinduced synthetic approaches to organoboron compounds have attracted significant attention in the recent years. Photochemical activation of organic molecules enables generation of reactive intermediates from a variety of precursors, resulting in borylation methods with improved and broader substrate scopes. The review summarizes recent developments in the area of photoinduced reactions of organoboron compounds with an emphasis on borylation of haloarenes, amine derivatives, and redox-active esters of carboxylic acids, as well as photoinduced rearrangements of organoboron compounds and photoinduced synthesis of organoboron compounds from alkenes and alkynes.
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Affiliation(s)
- Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Vu T Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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32
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Nguyen VD, Schoemaker FC, Blokhuis EM, Schall P. Measurement of the Curvature-Dependent Surface Tension in Nucleating Colloidal Liquids. Phys Rev Lett 2018; 121:246102. [PMID: 30608751 DOI: 10.1103/physrevlett.121.246102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Indexed: 06/09/2023]
Abstract
The curvature dependence of the surface tension is central to the nucleation of liquids, but remains difficult to access experimentally and predict theoretically. This curvature dependence arises from the curvature-dependent molecular structure, which, for small nuclei, can deviate significantly from that of the planar liquid interface. Simulations and density functional theory have been used to predict this curvature dependence, however with contradicting results. Here, we provide the first direct measurement of the curvature-dependent surface tension in nucleating colloidal liquids. We employ critical Casimir forces to finely adjust colloidal particle interactions and induce liquid nucleation, and image individual nuclei at the particle scale to measure their curvature-dependent surface tension directly from thermally excited surface distortions. Using continuum models, we elucidate the interplay between nucleus structure, particle pair potential, and surface tension. Our results reveal a 20% lower surface tension for nuclei of critical size compared to bulk liquids, leading to 3 orders of magnitude higher nucleation rates, thus highlighting the importance of surface tension curvature corrections for accurate prediction of nucleation rates.
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Affiliation(s)
- V D Nguyen
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - F C Schoemaker
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - E M Blokhuis
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, Netherlands
| | - P Schall
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
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Nguyen VT, Dang HT, Pham HH, Nguyen VD, Flores-Hansen C, Arman HD, Larionov OV. Highly Regio- and Stereoselective Catalytic Synthesis of Conjugated Dienes and Polyenes. J Am Chem Soc 2018; 140:8434-8438. [PMID: 29936839 DOI: 10.1021/jacs.8b05421] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Conjugated dienes and polyenes are typically synthesized by sequential introduction of C═C bonds. Here, we report a practical and scalable, catalytic dienylation that is highly regio- and stereoselective for both C═C bonds. The reaction is enabled by a stereoselective palladium-catalyzed cross-coupling that is preceded by a regioselective base-induced ring opening of readily available sulfolenes. The dienylation reaction is particularly useful for the synthesis of synthetically challenging dienes containing cis double bonds. We also show that the reaction can serve as a synthetic platform for the construction of conjugated polyenes.
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Affiliation(s)
- Vu T Nguyen
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Hang T Dang
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Hoang H Pham
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Viet D Nguyen
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Carsten Flores-Hansen
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Hadi D Arman
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
| | - Oleg V Larionov
- Department of Chemistry , The University of Texas at San Antonio , San Antonio , Texas 78249 , United States
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34
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Nguyen OTK, Phan ALT, Phan PT, Nguyen VD, Truong T, Le NTH, Le DT, Phan NTS. Ready Access to 3‐Substituted Quinoxalin‐2‐ones under Superparamagnetic Nanoparticle Catalysis. ChemistrySelect 2018. [DOI: 10.1002/slct.201702426] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Oanh T. K. Nguyen
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Anh L. T. Phan
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Phuong T. Phan
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Viet D. Nguyen
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Thanh Truong
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Nhan T. H. Le
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Dung T. Le
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
| | - Nam T. S. Phan
- Faculty of Chemical EngineeringHCMC University of Technology, VNU-HCM 268 Ly Thuong Kiet, District 10 Ho Chi Minh City Viet Nam, Phone: (+84 8) 38647256 ext. 5681, Fax: (+84 8) 38637504
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35
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Nguyen CK, Nguyen NN, Tran KN, Nguyen VD, Nguyen TT, Le DT, Phan NT. Copper ferrite superparamagnetic nanoparticles as a heterogeneous catalyst for directed phenol/formamide coupling. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.07.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Affiliation(s)
- Viet D. Nguyen
- From the Department of Radiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, MC 7800, San Antonio, TX 78229
| | - Achint K. Singh
- From the Department of Radiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, MC 7800, San Antonio, TX 78229
| | - Wilson B. Altmeyer
- From the Department of Radiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, MC 7800, San Antonio, TX 78229
| | - Bundhit Tantiwongkosi
- From the Department of Radiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr, MC 7800, San Antonio, TX 78229
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Abstract
Marine microorganisms have been recognized as potential sources of novel enzymes because they are relatively more stable than the corresponding enzymes derived from plants and animals. Enzymes from marine microorganisms also differ from homologous enzymes in terrestrial microorganisms based on salinity, pressure, temperature, and lighting conditions. Marine microbial enzymes can be used in diverse industrial applications. This chapter will focus on the biotechnological applications of marine enzymes and also their use as a tool of marine probiotics to improve host digestion (food digestion, food absorption, and mucus utilization) and cleave molecular signals involved in quorum sensing in pathogens to control disease in aquaculture.
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Affiliation(s)
- T H Nguyen
- Faculty of Food Technology, Nha Trang University, Nha Trang, Vietnam.
| | - V D Nguyen
- Institute of Biotechnology and Environment, Nha Trang University, Nha Trang, Vietnam.
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38
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Nguyen OTK, Nguyen LT, Truong NK, Nguyen VD, Nguyen AT, Le NTH, Le DT, Phan NTS. Synthesis of triphenylamines via ligand-free selective ring-opening of benzoxazoles or benzothiazoles under superparamagnetic nanoparticle catalysis. RSC Adv 2017. [DOI: 10.1039/c7ra06168d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synthesis of triphenylamines via ligand-free selective ring-opening of benzoxazoles or benzothiazoles with aryl halides under CuFe2O4 superparamagnetic nanoparticle catalysis.
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Affiliation(s)
- Oanh T. K. Nguyen
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Long T. Nguyen
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Nhu K. Truong
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Viet D. Nguyen
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Anh T. Nguyen
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Nhan T. H. Le
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Dung T. Le
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
| | - Nam T. S. Phan
- Faculty of Chemical Engineering
- HCMC University of Technology
- VNU-HCM
- Ho Chi Minh City
- Vietnam
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39
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Nguyen VD, Tantiwongkosi B, Weinheimer WJ, Miller FR. Positron-emission tomography/computed tomography imaging in head and neck oncology: An update. World J Otorhinolaryngol 2016; 6:23-32. [DOI: 10.5319/wjo.v6.i2.23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/09/2015] [Accepted: 03/18/2016] [Indexed: 02/06/2023] Open
Abstract
Cancers of the head and neck account for more than half a million cases worldwide annually, with a significant majority diagnosed as squamous cell carcinoma (HNSCC). Imaging studies such as contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI) and 18F-2-fluoro-2-deoxy-D-glucose positron-emission tomography/computed tomography (18F-FDG PET/CT) are widely used to determine the presence and extent of tumors and metastatic disease, both before and after treatment. Advances in PET/CT imaging have allowed it to emerge as a superior imaging modality compared to both CT and MRI, especially in detection of carcinoma of unknown primary, cervical lymph node metastasis, distant metastasis, residual/recurrent cancer and second primary tumors, often leading to alteration in management. PET/CT biomarker may further provide an overall assessment of tumor aggressiveness with prognostic implications. As new developments emerged leading to better understanding and use of PET/CT in head and neck oncology, the aim of this article is to review the roles of PET/CT in both pre- and post-treatment management of HNSCC and PET-derived parameters as prognostic indicators.
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40
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Abstract
Critical Casimir forces attract increasing interest due to their opportunities for reversible particle assembly in soft matter and nano science. These forces provide a thermodynamic analogue of the celebrated quantum mechanical Casimir force that arises from the confinement of vacuum fluctuations of the electromagnetic field. In its thermodynamic analogue, solvent fluctuations, confined between suspended particles, give rise to an attractive or repulsive force between the particles. Due to its unique temperature dependence, this effect allows in situ control of reversible assembly. Both the force magnitude and range vary with the solvent correlation length in a universal manner, adjusting with temperature from fractions of the thermal energy, k B T, and nanometre range to several ten kT and micrometer length scale. Combined with recent breakthroughs in the synthesis of complex particles, critical Casimir forces promise the design and assembly of complex colloidal structures, for fundamental studies of equilibrium and out-of-equilibrium phase behaviour. This review highlights recent developments in this evolving field, with special emphasis on the dynamic interaction control to assemble colloidal structures, in and out of equilibrium.
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Affiliation(s)
- V D Nguyen
- Van der Waals-Zeeman Institute, University of Amsterdam, The Netherlands. Physical Chemistry and Soft Matter, Wageningen University, Wageningen, The Netherlands
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41
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Nguyen VD, Torres WS, Laczkowski P, Marty A, Jamet M, Beigné C, Notin L, Vila L, Attané JP. Elementary depinning processes of magnetic domain walls under fields and currents. Sci Rep 2014; 4:6509. [PMID: 25270773 PMCID: PMC4180821 DOI: 10.1038/srep06509] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 07/24/2014] [Indexed: 11/09/2022] Open
Abstract
The probability laws associated to domain wall depinning under fields and currents have been studied in NiFe and FePt nanowires. Three basic domain wall depinning processes, associated to different potential landscapes, are found to appear identically in those systems with very different anisotropies. We show that these processes constitute the building blocks of any complex depinning mechanism. A Markovian analysis is proposed, that provides a unified picture of the depinning mechanism and an insight into the pinning potential landscape.
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Affiliation(s)
- V D Nguyen
- 1] INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France [2] Institut Néel and Université Joseph Fourier, 38042 Grenoble, France
| | - W Savero Torres
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - P Laczkowski
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - A Marty
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - M Jamet
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - C Beigné
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - L Notin
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - L Vila
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
| | - J P Attané
- INAC/CEA Grenoble and Université Joseph Fourier, 38054, Grenoble, France
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42
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Savero Torres W, Laczkowski P, Nguyen VD, Rojas Sanchez JC, Vila L, Marty A, Jamet M, Attané JP. Switchable spin-current source controlled by magnetic domain walls. Nano Lett 2014; 14:4016-4022. [PMID: 24874296 DOI: 10.1021/nl501453p] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Using nonlocal spin injection, spin-orbit coupling, or spincaloritronic effects, the manipulation of pure spin currents in nanostructures underlies the development of new spintronic devices. Here, we demonstrate the possibility to create switchable pure spin current sources, controlled by magnetic domain walls. When the domain wall is located at a given point of the magnetic circuit, a pure spin current is injected into a nonmagnetic wire. Using the reciprocal measurement configuration, we demonstrate that the proposed device can also be used as a pure spin current detector. Thanks to its simple geometry, this device can be easily implemented in spintronics applications; in particular, a single current source can be used both to induce the domain wall motion and to generate the spin signal.
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Affiliation(s)
- W Savero Torres
- INAC, CEA Grenoble , 17 avenue des Martyrs, 38054, Grenoble, France
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Shelke PB, Nguyen VD, Limaye AV, Schall P. Controlling colloidal morphologies by critical Casimir forces. Adv Mater 2013; 25:1499-1503. [PMID: 23293091 DOI: 10.1002/adma.201204458] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 11/13/2012] [Indexed: 05/28/2023]
Abstract
Active control over the assembly of colloidal and nanoparticles has important applications for the design of new nanostructured materials, but it is a difficult task. Here, a new method is presented to control the morphology of colloidal aggregates using critical Casimir forces. Via direct temperature control of critical Casimir forces, the particles are assembled into aggregates with well-defined architecture.
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Affiliation(s)
- Pradip B Shelke
- Department of Physics, Ahmednagar College, Ahmednagar, India
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Nguyen VD, Vila L, Laczkowski P, Marty A, Faivre T, Attané JP. Detection of domain-wall position and magnetization reversal in nanostructures using the magnon contribution to the resistivity. Phys Rev Lett 2011; 107:136605. [PMID: 22026884 DOI: 10.1103/physrevlett.107.136605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Indexed: 05/31/2023]
Abstract
We show that magnetization reversal detection can be achieved at room temperature using the contribution of magnons to resistivity, in 50 nm wide nanowires with either perpendicular anisotropy (FePt) or in-plane magnetization (NiFe). Even though these nanowires are made from single layers, simple magnetoresistance measurements can be used to measure switching fields, or to detect the position of a domain wall along a nanowire. Surprisingly, in NiFe nanowires, and for applied fields nearly parallel to the wire, the magnon contribution is found to dominate the classical anisotropic magnetoresistance.
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Nguyen VD, Auresenia J, Kosuge H, Tan RR, Brondial Y. Vacuum fermentation integrated with separation process for ethanol production. Biochem Eng J 2011. [DOI: 10.1016/j.bej.2011.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Nguyen VD, Griffith CN, Reus J, Barclay C, Alford S, Treat L, Hanthorn M, Ball L, Lawson L, Ledeen M, Buss J. Successful AV fistula creation does not lead to higher catheter use: the experience by the Northwest Renal Network 16 Vascular Access Quality Improvement Program. Four years follow-up. J Vasc Access 2008; 9:260-268. [PMID: 19085896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
BACKGROUND In 2002, the Center for Medicare and Medicaid Services (CMS) required all 18 Renal Networks to participate in a Vascular Access Quality Improvement Program (QIP). The Northwest Renal Network (NWRN 16) chose to increase arteriovenous fistula (AVF) use. NWRN 16 hypothesized that strategies which targeted the improvement of AVF rate and the reduction of catheter use were the same. In December 2001, 44.2% of hemodialysis (HD) patients in the NWRN 16 received HD using an AVF which met the Dialysis Outcome Quality Initiative (K/DOQI) 40% AVF guideline for prevalent patients. However, 43% of HD facilities (2869 patients) had less than 40% of AVF and higher HD catheter rates than the average Network catheter rates (25.0 vs. 20.3%). To address the needs of underperforming facilities, NWRN 16 provided education and tools for their vascular access decision makers to promote AVF creation and catheter reduction. METHODS In 2002, NWRN 16 sponsored four regional workshops targeted at nephrologists, vascular surgeons, HD nurses, and interventional radiologists. RESULTS Percentage of AVFs in use in invited facilities increased from 31.3% pre-intervention to 56.2% at 4 yrs: 78% increase (99% confidence interval: 77.8% to 81.5%). Percentage of catheters increased from 25% to 25.8%: 3.2% change over 4 yrs (99% confidence interval: 2.5% to 4%). CONCLUSION The success of Network 16's AVF interventions demonstrates the effectiveness of Network education promoting multidisciplinary teamwork, and innovative strategies to increase dramatically AVF use without substantial increase in catheter use.
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Affiliation(s)
- V D Nguyen
- Memorial Nephrology Associates, Olympia, WA 98506, USA.
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Nguyen VD, Robinson K, Griffith C. A guideline misguided: a review of the 2006 KDOQI Guideline on surveillance/monitoring and prophylactic angioplasty of hemodialysis grafts. J Vasc Access 2008; 9:111-112. [PMID: 18609525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Affiliation(s)
- V D Nguyen
- Memorial Nephrology Associates, Olympia, Washington 98506, USA.
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Nguyen VD, Treat L, Griffith C, Robinson K. Creation of secondary AV fistulas from failed hemodialysis grafts: the role of routine vein mapping. J Vasc Access 2007; 8:91-6. [PMID: 17534794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Pre-existing forearm grafts lead to dilatation of upper arm veins of the ipsilateral arm that greatly facilitates the creation of secondary arteriovenous fistulas (AVF). In this retrospective review of 18 patients, the routine and periodical revision of failed grafts were discontinued. Vein mapping by physical examination or Duplex studies was performed prior to graft failure and a secondary AVF was created when the graft failed. Using this management strategy, an AVF creation success rate of 95% was achieved despite high incidence of co-morbidity factors within the patient population. This success rate demonstrates the value of vein selection by vascular mapping prior to graft failure and early vascular access planning in the successful creation of secondary AVF.
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Affiliation(s)
- V D Nguyen
- Memorial Nephrology Associates, Olympia, Washington 98506, USA.
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Nguyen VD, Lawson L, Ledeen M, Treat L, Buss J, Barclay C, Alford S, Reus J, Griffith C. Successful multidisciplinary interventions for arterio-venous fistula creation by the Pacific Northwest Renal Network 16 vascular access quality improvement program. J Vasc Access 2007; 8:3-11. [PMID: 17393364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
BACKGROUND In December 2001, 44.2% of hemodialysis (HD) patients in the Northwest Renal Network (NWRN 16) received dialysis using an arteriovenous fistula (AVF). Substantial differences were noted in percentages of patients with AVF, ranging from 5% to 90% of the facility population, suggesting wide variation in physician practice patterns within the Network. To address the needs of facilities having < 40% AVF, NWRN 16 provided education and tools for their vascular access decision-makers to promote AVF creation. METHODS In 2002, the Network sponsored 4 regional workshops targeted to nephrologists, vascular surgeons, dialysis nurses, and interventional radiologists. RESULTS 46 facilities (43% of all Network facilities) had <40% AVF in use in December, 2001, dialyzing 2940 patients (Invited Units). Percent AVF in use in all the Invited Facilities increased from 31.3% pre-intervention to 39.8% at 1 year (p<0.001 vs pre) to 56.2% at four years: 79.8% increase in the prevalent AVF rate over a four-year period (95% confidence interval: 77.8% to 81.7%). CONCLUSION Low prevalent AVF rates in many NWRN 16 facilities may have resulted from differences in physician practice patterns. The success of Network 16 AVF Intervention demonstrates the effectiveness of Network education promoting multidisciplinary teamwork, innovative strategies to increase AVF rates among dialysis patients.
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Affiliation(s)
- V D Nguyen
- Memorial Nephrology Associates, Olympia, Washington 98506, USA.
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