1
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Dang HT, Porey A, Nand S, Trevino R, Manning-Lorino P, Hughes WB, Fremin SO, Thompson WT, Dhakal SK, Arman HD, Larionov OV. Kinetically-driven reactivity of sulfinylamines enables direct conversion of carboxylic acids to sulfinamides. Chem Sci 2023; 14:13384-13391. [PMID: 38033883 PMCID: PMC10685282 DOI: 10.1039/d3sc04727j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 10/08/2023] [Indexed: 12/02/2023] Open
Abstract
Sulfinamides are some of the most centrally important four-valent sulfur compounds that serve as critical entry points to an array of emergent medicinal functional groups, molecular tools for bioconjugation, and synthetic intermediates including sulfoximines, sulfonimidamides, and sulfonimidoyl halides, as well as a wide range of other S(iv) and S(vi) functionalities. Yet, the accessible chemical space of sulfinamides remains limited, and the approaches to sulfinamides are largely confined to two-electron nucleophilic substitution reactions. We report herein a direct radical-mediated decarboxylative sulfinamidation that for the first time enables access to sulfinamides from the broad and structurally diverse chemical space of carboxylic acids. Our studies show that the formation of sulfinamides prevails despite the inherent thermodynamic preference for the radical addition to the nitrogen atom, while a machine learning-derived model facilitates prediction of the reaction efficiency based on computationally generated descriptors of the underlying radical reactivity.
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Affiliation(s)
- Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Arka Porey
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Sachchida Nand
- 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
| | - Patrick Manning-Lorino
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - William B Hughes
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Seth O Fremin
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - William T Thompson
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Shree Krishna Dhakal
- 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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2
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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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3
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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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4
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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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5
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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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Herrera L, Llanes A, Álvarez J, Degracia K, Restrepo CM, Rivera R, Stephens DE, Dang HT, Larionov OV, Lleonart R, Fernández PL. Antileishmanial activity of a new chloroquine analog in an animal model of Leishmania panamensis infection. Int J Parasitol Drugs Drug Resist 2020; 14:56-61. [PMID: 32950020 PMCID: PMC7502791 DOI: 10.1016/j.ijpddr.2020.08.002] [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] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/14/2020] [Accepted: 08/07/2020] [Indexed: 01/29/2023]
Abstract
Leishmania panamensis is a relevant causative agent of tegumentary leishmaniasis in several Latin American countries. Available antileishmanial drugs have several limitations including relatively high toxicity, difficult administration, high production costs and the emergence of resistance in circulating strains. Therefore, the identification of new molecules as potential therapeutics for leishmaniasis is of great relevance. Here, we developed a murine model of L. panamensis infection and evaluated the effect of a new compound in vivo. After treatment of animals with the compound, we observed a significant reduction of inflammation and parasite load at the inoculation site, in a dose-dependent manner. We observed a reduction in IL-10 production by popliteal lymph nodes cells of infected mice. These results pave the way for future evaluation of this compound as a potential antileishmanial drug or as a suitable scaffold for lead optimization strategies.
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Affiliation(s)
- Lizzi Herrera
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama; Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh, 522510, India
| | - Alejandro Llanes
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama; Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh, 522510, India
| | - Jennifer Álvarez
- Escuela de Biología, Facultad de Ciencias Naturales, Exactas y Tecnología, Universidad de Panamá. Panama, 0801, Panama
| | - Kissy Degracia
- Escuela de Biotecnología, Facultad de Ciencias de la Salud Dr. William C. Gorgas, Universidad Latina de Panama, 0801, Panama
| | - Carlos M Restrepo
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama
| | - Rene Rivera
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama
| | - David E Stephens
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX, 78249, United States
| | - Hang T Dang
- 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
| | - Ricardo Lleonart
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama
| | - Patricia L Fernández
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Edificio 208, Ciudad del Saber, Apartado 0843-01103, Panama, 0801, Panama.
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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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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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9
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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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10
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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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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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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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14
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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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15
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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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16
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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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17
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de la Guardia C, Stephens DE, Dang HT, Quijada M, Larionov OV, Lleonart R. Antiviral Activity of Novel Quinoline Derivatives against Dengue Virus Serotype 2. Molecules 2018; 23:molecules23030672. [PMID: 29547522 PMCID: PMC5997395 DOI: 10.3390/molecules23030672] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [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: 02/19/2018] [Revised: 03/13/2018] [Accepted: 03/15/2018] [Indexed: 12/14/2022] Open
Abstract
Dengue virus causes dengue fever, a debilitating disease with an increasing incidence in many tropical and subtropical territories. So far, there are no effective antivirals licensed to treat this virus. Here we describe the synthesis and antiviral activity evaluation of two compounds based on the quinoline scaffold, which has shown potential for the development of molecules with various biological activities. Two of the tested compounds showed dose-dependent inhibition of dengue virus serotype 2 in the low and sub micromolar range. The compounds 1 and 2 were also able to impair the accumulation of the viral envelope glycoprotein in infected cells, while showing no sign of direct virucidal activity and acting possibly through a mechanism involving the early stages of the infection. The results are congruent with previously reported data showing the potential of quinoline derivatives as a promising scaffold for the development of new antivirals against this important virus.
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Affiliation(s)
- Carolina de la Guardia
- Institute of Scientific Research and High Technology Services (INDICASAT AIP), PO 0843-01103 City of Panama, Panama.
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522510, Andhra Pradesh, India.
| | - David E Stephens
- Department of Chemistry, University of Texas at San Antonio, San Antonio, TX 78249, USA.
| | - Hang T Dang
- Department of Chemistry, University of Texas at San Antonio, San Antonio, TX 78249, USA.
| | - Mario Quijada
- Institute of Scientific Research and High Technology Services (INDICASAT AIP), PO 0843-01103 City of Panama, Panama.
| | - Oleg V Larionov
- Department of Chemistry, University of Texas at San Antonio, San Antonio, TX 78249, USA.
| | - Ricardo Lleonart
- Institute of Scientific Research and High Technology Services (INDICASAT AIP), PO 0843-01103 City of Panama, Panama.
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18
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Jin S, Nguyen VT, Dang HT, Nguyen DP, Arman HD, Larionov OV. Photoinduced Carboborative Ring Contraction Enables Regio- and Stereoselective Synthesis of Multiply Substituted Five-Membered Carbocycles and Heterocycles. J Am Chem Soc 2017; 139:11365-11368. [PMID: 28780859 DOI: 10.1021/jacs.7b07128] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We report herein a photoinduced carboborative ring contraction of monounsaturated six-membered carbocycles and heterocycles. The reaction produces substituted five-membered ring systems stereoselectively and on preparative scales. The products feature multiple stereocenters, including contiguous quaternary carbons. We show that the reaction can serve as a synthetic platform for ring system alteration of natural products. The reaction can also be used in natural product synthesis. A concise total synthesis of artalbic acid has been enabled by a sequence of photoinduced carboborative ring contraction, Rauhut-Currier reaction, and nitrilase-catalyzed hydrolysis. The synthetic utility of the reaction has been further demonstrated by converting the intermediate organoboranes to alcohols, amines, and alkenes.
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Affiliation(s)
- 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
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio , San Antonio, Texas 78249, United States
| | - Dat P 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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19
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Dang HT, Park HK, Myung SC, Kim W. Development of a novel PCR assay based on the 16S-23S rRNA internal transcribed spacer region for the detection of Lactococcus garvieae. J Fish Dis 2012; 35:481-487. [PMID: 22607639 DOI: 10.1111/j.1365-2761.2012.01382.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Lactococcus garvieae is recognized as an emerging pathogen in fish. Several PCR-based methods have been developed for the detection and identification of L. garvieae; however, the sensitivity of these methods is still in question regarding the discrimination of this organism from other closely related species. Two primers, ITSLg30F and ITSLg319R, were designed from the sequence in the 16S-23S internal transcribed spacer (ITS) region and used for the specific detection of L. garvieae. L. garvieae strains including fish isolates were positive by this method. In contrast, previously developed PCR methods showed false-positive results with non-L. garvieae species. Our results indicate that a PCR method using the newly designed ITS primer set provides a sensitive and efficient tool for the detection of L. garvieae in fish and aquaculture environments.
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Affiliation(s)
- H T Dang
- Department of Microbiology, Chung-Ang University College of Medicine, Seoul, Korea
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Affiliation(s)
- Ayfer Kamali Polat
- Magee-Womens Hospital, University of Pittsburgh Medical Center, Department of Surgical Oncology, Pittsburgh, PA
| | - Hang T. Dang
- Magee-Womens Hospital, University of Pittsburgh Medical Center, Department of Surgical Oncology, Pittsburgh, PA
| | - Atilla Soran
- Magee-Womens Hospital, University of Pittsburgh Medical Center, Department of Surgical Oncology, Pittsburgh, PA
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21
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Whitfield GK, Remus LS, Jurutka PW, Zitzer H, Oza AK, Dang HT, Haussler CA, Galligan MA, Thatcher ML, Encinas Dominguez C, Haussler MR. Functionally relevant polymorphisms in the human nuclear vitamin D receptor gene. Mol Cell Endocrinol 2001; 177:145-59. [PMID: 11377830 DOI: 10.1016/s0303-7207(01)00406-3] [Citation(s) in RCA: 290] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The functional significance of two unlinked human vitamin D receptor (hVDR) gene polymorphisms was evaluated in twenty human fibroblast cell lines. Genotypes at both a Fok I restriction site (F/f) in exon II and a singlet (A) repeat in exon IX (L/S) were determined, and relative transcription activities of endogenous hVDR proteins were measured using a transfected, 1,25-dihydroxyvitamin D(3)-responsive reporter gene. Observed activities ranged from 2--100-fold induction by hormone, with higher activity being displayed by the F and the L biallelic forms. Only when genotypes at both sites were considered simultaneously did statistically significant differences emerge. Moreover, the correlation between hVDR activity and genotype segregated further into clearly defined high and low activity groups with similar genotypic distributions. These results not only demonstrate functional relevance for both the F/f and L/S common polymorphisms in hVDR, but also provide novel evidence for a third genetic variable impacting receptor potency.
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Affiliation(s)
- G K Whitfield
- Department of Biochemistry, College of Medicine, 1501 N. Campbell Ave., University of Arizona, Tucson, AZ 85724, USA
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22
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Jurutka PW, Remus LS, Whitfield GK, Thompson PD, Hsieh JC, Zitzer H, Tavakkoli P, Galligan MA, Dang HT, Haussler CA, Haussler MR. The polymorphic N terminus in human vitamin D receptor isoforms influences transcriptional activity by modulating interaction with transcription factor IIB. Mol Endocrinol 2000; 14:401-20. [PMID: 10707958 DOI: 10.1210/mend.14.3.0435] [Citation(s) in RCA: 229] [Impact Index Per Article: 9.5] [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: 11/19/2022] Open
Abstract
The human vitamin D receptor (hVDR) is a ligand-regulated transcription factor that mediates the actions of the 1,25-dihydroxyvitamin D3 hormone to effect bone mineral homeostasis. Employing mutational analysis, we characterized Arg-18/Arg-22, hVDR residues immediately N-terminal of the first DNA binding zinc finger, as vital for contact with human basal transcription factor IIB (TFIIB). Alteration of either of these basic amino acids to alanine also compromised hVDR transcriptional activity. In contrast, an artificial hVDR truncation devoid of the first 12 residues displayed both enhanced interaction with TFIIB and transactivation. Similarly, a natural polymorphic variant of hVDR, termed F/M4 (missing a FokI restriction site), which lacks only the first three amino acids (including Glu-2), interacted more efficiently with TFIIB and also possessed elevated transcriptional activity compared with the full-length (f/M1) receptor. It is concluded that the functioning of positively charged Arg-18/Arg-22 as part of an hVDR docking site for TFIIB is influenced by the composition of the adjacent polymorphic N terminus. Increased transactivation by the F/M4 neomorphic hVDR is hypothesized to result from its demonstrated enhanced association with TFIIB. This proposal is supported by the observed conversion of f/M1 hVDR activity to that of F/M4 hVDR, either by overexpression of TFIIB or neutralization of the acidic Glu-2 by replacement with alanine in f/M1 hVDR. Because the f VDR genotype has been associated with lower bone mineral density in diverse populations, one factor contributing to a genetic predisposition to osteoporosis may be the F/f polymorphism that dictates VDR isoforms with differential TFIIB interaction.
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Affiliation(s)
- P W Jurutka
- Department of Biochemistry, College of Medicine, University of Arizona, Tuscon 85724, USA
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23
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Hsieh JC, Whitfield GK, Oza AK, Dang HT, Price JN, Galligan MA, Jurutka PW, Thompson PD, Haussler CA, Haussler MR. Characterization of unique DNA-binding and transcriptional-activation functions in the carboxyl-terminal extension of the zinc finger region in the human vitamin D receptor. Biochemistry 1999; 38:16347-58. [PMID: 10587460 DOI: 10.1021/bi9916574] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The vitamin D receptor (VDR) binds 1,25-dihydroxyvitamin D(3) and mediates its actions on gene transcription by heterodimerizing with retinoid X receptors (RXRs) on direct repeat (DR+3) vitamin D responsive elements (VDREs) located in target genes. The VDRE binding function of VDR has been primarily ascribed to the zinc finger region (residues 24-87). To define the minimal VDRE binding domain for human VDR (hVDR), a series of C-terminally truncated hVDR mutants (Delta134, Delta113, Delta102, Delta90, Delta84, Delta80, and Delta60) was generated and expressed in bacteria. Only the Delta134 and Delta113 mutants bound the VDRE (predominantly as monomers), suggesting that, in addition to the conserved zinc finger region of hVDR, as many as 25 amino acids in a C-terminal extension (CTE) participate in DNA binding. Site-directed mutagenesis of conserved charged residues in full-length hVDR was then performed to dissect the functional significance of the CTE (residues 88-112) in the context of the complete hVDR-RXR-VDRE interaction. Functional assays revealed that E98K/E99K, R102A/K103A/R104A, and K109A/R110A/K111A mutant hVDRs possessed dramatically reduced DNA binding and transcriptional activities, whereas distinct point mutants, such as K103A, bound to DNA normally but lacked transcriptional activity. Therefore, the boundary for the minimal DNA-binding domain in hVDR extends C-terminal of the zinc fingers to Lys-111, with clusters of highly conserved charged amino acids playing a crucial role in binding to the DR+3 element. Further, individual residues in this region (e.g., Lys-103) may lie on the opposing face of a DNA-binding alpha-helix, where they could contact transcriptional coactivators or basal transcription factors.
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Affiliation(s)
- J C Hsieh
- Department of Biochemistry, College of Medicine, The University of Arizona, Tucson 85724, USA
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Colletti PM, Dang HT, Deseran MW, Kerr RM, Boswell WD, Ralls PW. Spinal MR imaging in suspected metastases: correlation with skeletal scintigraphy. Magn Reson Imaging 1991; 9:349-55. [PMID: 1881253 DOI: 10.1016/0730-725x(91)90422-i] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bone scintigraphy (RN) and magnetic resonance imaging (MR) were prospectively and retrospectively correlated in 64 patients with suspected spinal metastatic disease and possible spinal cord compression. Images were retrospectively interpreted and compared with the prospective official RN and MR reports to help decide relative prospective lesion conspicuity. Spinal lesions were confirmed by radiography, computed tomography, myelography or MR and RN follow-up in 56 patients (88%). Prospectively, MR detected 11 lesions not reported on RN while RN detected two lesions not reported on MR. Retrospective review of RN detected six lesions previously not reported. Retrospectively MR showed all lesions. Those lesions seen only in retrospect by RN were rather subtle and would be difficult to detect prospectively. In general, lesions not well seen on RN had relatively more bone marrow abnormality and less cortical bone involvement. In some cases, MR imaging shows spinal marrow lesions not well seen on planar RN.
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Affiliation(s)
- P M Colletti
- Department of Radiology, University of Southern California School of Medicine, Los Angeles 90033
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Abstract
MRI evaluation of primary cervical lymphoma has not been reported. We report such a case of primary cervical lymphoma, a lesion well seen and well delineated from normal tissue by MRI. Although primary lymphoma of the cervix is a rare entity, the disease does exist and can be well demonstrated by MRI. We evaluated the MR appearance of this lesion with both nonenhanced and gadolinium-enhanced imaging.
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Affiliation(s)
- H T Dang
- University of Southern California School of Medicine, Department of Radiology, Los Angeles
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