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Ivanova E, Osipova M, Vasilieva T, Eremkin A, Markova S, Zazhivihina E, Smirnova S, Mitrasov Y, Nasakin O. The Recycling of Substandard Rocket Fuel N,N-Dimethylhydrazine via the Involvement of Its Hydrazones Derived from Glyoxal, Acrolein, Metacrolein, Crotonaldehyde, and Formaldehyde in Organic Synthesis. Int J Mol Sci 2023; 24:17196. [PMID: 38139025 PMCID: PMC10742919 DOI: 10.3390/ijms242417196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/05/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
"Heptil" (unsymmetrical dimethylhydrazine-UDMH) is extensively employed worldwide as a propellant for rocket engines. However, UDMH constantly loses its properties as a result of its continuous and uncontrolled absorption of moisture, which cannot be rectified. This situation threatens its long-term usability. UDMH is an exceedingly toxic compound (Hazard Class 1), which complicates its transportation and disposal. Incineration is currently the only method used for its disposal, but this process generates oxidation by-products that are even more toxic than the original UDMH. A more benign approach involves its immediate reaction with a formalin solution to form 1,1-dimethyl-2-methylene hydrazone (MDH), which is significantly less toxic by an order of magnitude. MDH can then be polymerized under acidic conditions, and the resulting product can be burned, yielding substantial amounts of nitrogen oxides. This review seeks to shift the focus of MDH from incineration towards its application in the synthesis of relatively non-toxic and readily available analogs of various pharmaceutical substances. We aim to bring the attention of the international chemical community to the distinctive properties of MDH, as well as other hydrazones (such as glyoxal, acrolein, crotonal, and meta-crolyl), wherein each structural fragment can initiate unique transformations that have potential applications in molecular design, pharmaceutical research, and medicinal chemistry.
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Affiliation(s)
- Elizaveta Ivanova
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Margarita Osipova
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Tatyana Vasilieva
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Alexey Eremkin
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Svetlana Markova
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Ekaterina Zazhivihina
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Svetlana Smirnova
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
| | - Yurii Mitrasov
- Organic and Pharmaceutical Chemistry Department, Yakovlev Chuvash State Pedagogical University, K. Marx Street, 38, 428000 Cheboksary, Russia;
| | - Oleg Nasakin
- Organic and Pharmaceutical Chemistry Department, Ulyanov Chuvash State University, Moskovsky Prospect, 15, 428015 Cheboksary, Russia; (E.I.); (M.O.); (T.V.); (A.E.); (S.M.); (E.Z.); (S.S.)
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2
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Li W, Xin J, Zhai P, Lin J, Huang S, Gao W, Li X. Access to highly functionalized imidazolones bearing α-amino acid esters via KOH-promoted annulation of amidines, nitrosoarenes and malonic esters. Org Biomol Chem 2021; 19:6473-6477. [PMID: 34236374 DOI: 10.1039/d1ob00930c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient approach to obtain highly functionalized imidazolones bearing α-amino acid esters through KOH-mediated one-pot three-component annulation of amidines, nitrosoarenes and malonic esters is reported. This reaction features broad substrate scope, a cheap and readily available promoter, good to high yields for most substrates and mild reaction conditions. The mechanism study shows that the KOH-mediated formation of the imine intermediate via the reaction of nitrosoarenes with malonic esters is a key step.
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Affiliation(s)
- Wenhui Li
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
| | - Jie Xin
- Feicheng Hospital Affiliated to Shandong First Medical University, Feicheng 271600, China
| | - Pingan Zhai
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
| | - Jianying Lin
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
| | - Shuangping Huang
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
| | - Wenchao Gao
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
| | - Xing Li
- College of Biomedical Engineering, Taiyuan University of Technology, 79 West Yingze Street, Taiyuan 030024, China.
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3
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Steinmetzger C, Bessi I, Lenz AK, Höbartner C. Structure-fluorescence activation relationships of a large Stokes shift fluorogenic RNA aptamer. Nucleic Acids Res 2020; 47:11538-11550. [PMID: 31740962 PMCID: PMC7145527 DOI: 10.1093/nar/gkz1084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/13/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
The Chili RNA aptamer is a 52 nt long fluorogen-activating RNA aptamer (FLAP) that confers fluorescence to structurally diverse derivatives of fluorescent protein chromophores. A key feature of Chili is the formation of highly stable complexes with different ligands, which exhibit bright, highly Stokes-shifted fluorescence emission. In this work, we have analyzed the interactions between the Chili RNA and a family of conditionally fluorescent ligands using a variety of spectroscopic, calorimetric and biochemical techniques to reveal key structure–fluorescence activation relationships (SFARs). The ligands under investigation form two categories with emission maxima of ∼540 or ∼590 nm, respectively, and bind with affinities in the nanomolar to low-micromolar range. Isothermal titration calorimetry was used to elucidate the enthalpic and entropic contributions to binding affinity for a cationic ligand that is unique to the Chili aptamer. In addition to fluorescence activation, ligand binding was also observed by NMR spectroscopy, revealing characteristic signals for the formation of a G-quadruplex only upon ligand binding. These data shed light on the molecular features required and responsible for the large Stokes shift and the strong fluorescence enhancement of red and green emitting RNA–chromophore complexes.
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Affiliation(s)
- Christian Steinmetzger
- Institute of Organic Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Irene Bessi
- Institute of Organic Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Ann-Kathrin Lenz
- Institute of Organic Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Claudia Höbartner
- Institute of Organic Chemistry, Julius-Maximilians-University Würzburg, Am Hubland, 97074 Würzburg, Germany
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4
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Dolgopolova EA, Berseneva AA, Faillace MS, Ejegbavwo OA, Leith GA, Choi SW, Gregory HN, Rice AM, Smith MD, Chruszcz M, Garashchuk S, Mythreye K, Shustova NB. Confinement-Driven Photophysics in Cages, Covalent−Organic Frameworks, Metal–Organic Frameworks, and DNA. J Am Chem Soc 2020; 142:4769-4783. [DOI: 10.1021/jacs.9b13505] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Ekaterina A. Dolgopolova
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Anna A. Berseneva
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Martín S. Faillace
- INFIQC-UNC, CONICET, Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba X5000HUA, Argentina
| | - Otega A. Ejegbavwo
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Gabrielle A. Leith
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Seok W. Choi
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Haley N. Gregory
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Allison M. Rice
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Mark D. Smith
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Maksymilian Chruszcz
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Sophya Garashchuk
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Karthikeyan Mythreye
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Natalia B. Shustova
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
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Chopra B, Dhingra AK, Prasad DN. Imidazole: An Emerging Scaffold Showing its Therapeutic Voyage to Develop Valuable Molecular Entities. Curr Drug Res Rev 2019; 12:103-117. [PMID: 31782364 DOI: 10.2174/2589977511666191129152038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 10/14/2019] [Accepted: 10/17/2019] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Imidazole is a heterocyclic moiety having immense biological importance. Since ancient times, the imidazole nucleus is considered to be a promising moiety in the field of chemistry. Preliminary in vitro and in vivo studies have provided valuable scientific evidence for its use. Subsequently, imidazole constitutes a new class of compounds for new drug development as the presence of this nucleus in diverse therapeutic categories viz; antimicrobial, anti-inflammatory, anticancer, immunomodulator, antiviral etc. has made it an interesting moiety for the design and development of new pharmacological agents. Thus, this review aims to summarize the reported molecular entities which were synthesized by using conventional as well as microwave processes, chemistry and biological potential of imidazole containing heterocyclic molecules while identifying potential areas of further research on imidazole. RESULTS The review comprises literature pertaining to the evidence-based pharmacological or therapeutic potential of imidazole using published articles and worldwide databases. Various pharmacological experiments using different models exclusively proved the potential of imidazole. SUMMARY Focusing on the discovery and development of new imidazole nucleus based molecules at a faster rate, there is a need to search previous information available in the market in the field of medicinal chemistry. Therefore, the present review aims to elaborate the therapeutic worth of imidazole and its analogs.
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Affiliation(s)
- Bhawna Chopra
- Department of Pharmaceutical Science, Guru Gobind Singh College of Pharmacy, Yamuna Nagar-135001, Haryana, India
| | - Ashwani K Dhingra
- Department of Pharmaceutical Science, Guru Gobind Singh College of Pharmacy, Yamuna Nagar-135001, Haryana, India
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Haung JY, Barve IJ, Sun CM. One-pot synthesis of 4-arylidene imidazolin-5-ones by reaction of amino acid esters with isocyanates and α-bromoketones. Org Biomol Chem 2019; 17:3040-3047. [PMID: 30816898 DOI: 10.1039/c8ob03111h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A simple and new multicomponent reaction for the one-pot synthesis of substituted 4-arylidene imidazolin-5-ones from l-amino acid methyl esters, iso-, isothio- or isoselenocyanates, and α-bromoketones is demonstrated. Isolation of thiohydantoin and 5-benzylidene 2-thioxoimidazolidin-4-one intermediates revealed a possible reaction mechanism. The strategy was further extended to the synthesis of 2-iminothiazolines and 2-thioxoimidazolin-4-ones.
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Affiliation(s)
- Jia-Yun Haung
- Department of Applied Chemistry, 1001 Ta-Hseuh Road, National Chiao-Tung University, Hsinchu 300-10, Taiwan.
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7
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Steinmetzger C, Palanisamy N, Gore KR, Höbartner C. A Multicolor Large Stokes Shift Fluorogen-Activating RNA Aptamer with Cationic Chromophores. Chemistry 2019; 25:1931-1935. [PMID: 30485561 DOI: 10.1002/chem.201805882] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Indexed: 12/31/2022]
Abstract
Large Stokes shift (LSS) fluorescent proteins (FPs) exploit excited state proton transfer pathways to enable fluorescence emission from the phenolate intermediate of their internal 4-hydroxybenzylidene imidazolone (HBI) chromophore. An RNA aptamer named Chili mimics LSS FPs by inducing highly Stokes-shifted emission from several new green and red HBI analogues that are non-fluorescent when free in solution. The ligands are bound by the RNA in their protonated phenol form and feature a cationic aromatic side chain for increased RNA affinity and reduced magnesium dependence. In combination with oxidative functionalization at the C2 position of the imidazolone, this strategy yielded DMHBO+ , which binds to the Chili aptamer with a low-nanomolar KD . Because of its highly red-shifted fluorescence emission at 592 nm, the Chili-DMHBO+ complex is an ideal fluorescence donor for Förster resonance energy transfer (FRET) to the rhodamine dye Atto 590 and will therefore find applications in FRET-based analytical RNA systems.
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Affiliation(s)
- Christian Steinmetzger
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Navaneethan Palanisamy
- International Max Planck Research School Molecular Biology, University of Göttingen, Germany.,Present address: BIOSS Center for Biological Signaling Studies, University of Freiburg, Germany
| | - Kiran R Gore
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.,Present address: Department of Chemistry, University of Mumbai, India
| | - Claudia Höbartner
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany.,International Max Planck Research School Molecular Biology, University of Göttingen, Germany.,Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
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8
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Synthesis of dioxolanes and oxazolidines by silica gel catalysis. MONATSHEFTE FUR CHEMIE 2018. [DOI: 10.1007/s00706-018-2198-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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9
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Jones BL, Walker C, Azizi B, Tolbert L, Williams LD, Snell TW. Conservation of estrogen receptor function in invertebrate reproduction. BMC Evol Biol 2017; 17:65. [PMID: 28259146 PMCID: PMC5336670 DOI: 10.1186/s12862-017-0909-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 02/08/2017] [Indexed: 11/12/2022] Open
Abstract
Background Rotifers are microscopic aquatic invertebrates that reproduce both sexually and asexually. Though rotifers are phylogenetically distant from humans, and have specialized reproductive physiology, this work identifies a surprising conservation in the control of reproduction between humans and rotifers through the estrogen receptor. Until recently, steroid signaling has been observed in only a few invertebrate taxa and its role in regulating invertebrate reproduction has not been clearly demonstrated. Insights into the evolution of sex signaling pathways can be gained by clarifying how receptors function in invertebrate reproduction. Results In this paper, we show that a ligand-activated estrogen-like receptor in rotifers binds human estradiol and regulates reproductive output in females. In other invertebrates characterized thus far, ER ligand binding domains have occluded ligand-binding sites and the ERs are not ligand activated. We have used a suite of computational, biochemical and biological techniques to determine that the rotifer ER binding site is not occluded and can bind human estradiol. Conclusions Our results demonstrate that this mammalian hormone receptor plays a key role in reproduction of the ancient microinvertebrate Brachinous manjavacas. The presence and activity of the ER within the phylum Rotifera indicates that the ER structure and function is highly conserved throughout animal evolution. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0909-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Brande L Jones
- School of Biology, Georgia Institute of Technology, Atlanta, GA, 30332-0230, USA.
| | - Chris Walker
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332-0230, USA
| | - Bahareh Azizi
- Dasman Diabetes Institute, P.O. Box 1180, Dasman, 15462, Kuwait
| | - Laren Tolbert
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332-0230, USA
| | - Loren Dean Williams
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332-0230, USA
| | - Terry W Snell
- School of Biology, Georgia Institute of Technology, Atlanta, GA, 30332-0230, USA
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10
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Floyd DM, Stein P, Wang Z, Liu J, Castro S, Clark JA, Connelly M, Zhu F, Holbrook G, Matheny A, Sigal MS, Min J, Dhinakaran R, Krishnan S, Bashyum S, Knapp S, Guy RK. Hit-to-Lead Studies for the Antimalarial Tetrahydroisoquinolone Carboxanilides. J Med Chem 2016; 59:7950-62. [PMID: 27505686 DOI: 10.1021/acs.jmedchem.6b00752] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phenotypic whole-cell screening in erythrocytic cocultures of Plasmodium falciparum identified a series of dihydroisoquinolones that possessed potent antimalarial activity against multiple resistant strains of P. falciparum in vitro and show no cytotoxicity to mammalian cells. Systematic structure-activity studies revealed relationships between potency and modifications at N-2, C-3, and C-4. Careful structure-property relationship studies, coupled with studies of metabolism, addressed the poor aqueous solubility and metabolic vulnerability, as well as potential toxicological effects, inherent in the more potent primary screening hits such as 10b. Analogues 13h and 13i, with structural modifications at each site, were shown to possess excellent antimalarial activity in vivo. The (+)-(3S,4S) enantiomer of 13i and similar analogues were identified as the more potent. On the basis of these studies, we have selected (+)-13i for further study as a preclinical candidate.
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Affiliation(s)
- David M Floyd
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - Philip Stein
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - Zheng Wang
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - Jian Liu
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - Steve Castro
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - Julie A Clark
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Michele Connelly
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Fangyi Zhu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Gloria Holbrook
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Amy Matheny
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Martina S Sigal
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Jaeki Min
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
| | - Rajkumar Dhinakaran
- Syngene International Ltd. , Plot No. 2 & 3, Bommasandra IV Phase, Jigani Link Road, Bangalore, India 560 099
| | - Senthil Krishnan
- Syngene International Ltd. , Plot No. 2 & 3, Bommasandra IV Phase, Jigani Link Road, Bangalore, India 560 099
| | - Sridevi Bashyum
- Syngene International Ltd. , Plot No. 2 & 3, Bommasandra IV Phase, Jigani Link Road, Bangalore, India 560 099
| | - Spencer Knapp
- Department of Chemistry & Chemical Biology, Rutgers The State University of New Jersey , 610 Taylor Road, Piscataway, New Jersey 08854 United States
| | - R Kiplin Guy
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , 262 Danny Thomas Place, Memphis, Tennessee 38105 United States
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11
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Dolgopolova EA, Moore TM, Fellows WB, Smith MD, Shustova NB. Photophysics of GFP-related chromophores imposed by a scaffold design. Dalton Trans 2016; 45:9884-91. [DOI: 10.1039/c5dt05063d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In this paper, a rigid scaffold imposes the photophysics of chromophores with a benzylidene imidazolidinone core by mimicking the β-barrel structure of the green fluorescent protein (GFP) and its analogs.
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Affiliation(s)
- E. A. Dolgopolova
- Department of Chemistry and Biochemistry
- University of South Carolina
- Columbia
- USA
| | - T. M. Moore
- Department of Chemistry and Biochemistry
- University of South Carolina
- Columbia
- USA
| | - W. B. Fellows
- Department of Chemistry and Biochemistry
- University of South Carolina
- Columbia
- USA
| | - M. D. Smith
- Department of Chemistry and Biochemistry
- University of South Carolina
- Columbia
- USA
| | - N. B. Shustova
- Department of Chemistry and Biochemistry
- University of South Carolina
- Columbia
- USA
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12
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Baranov MS, Solntsev KM, Baleeva NS, Mishin AS, Lukyanov SA, Lukyanov KA, Yampolsky IV. Red-shifted fluorescent aminated derivatives of a conformationally locked GFP chromophore. Chemistry 2014; 20:13234-41. [PMID: 25171432 DOI: 10.1002/chem.201403678] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Indexed: 11/09/2022]
Abstract
A novel class of fluorescent dyes based on conformationally locked GFP chromophore is reported. These dyes are characterized by red-shifted spectra, high fluorescence quantum yields and pH-independence in physiological pH range. The intra- and intermolecular mechanisms of radiationless deactivation of ABDI-BF2 fluorophore by selective structural locking of various conformational degrees of freedom were studied. A unique combination of solvatochromic and lipophilic properties together with "infinite" photostability (due to a dynamic exchange between free and bound dye) makes some of the novel dyes promising bioinspired tools for labeling cellular membranes, lipid drops and other organelles.
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Affiliation(s)
- Mikhail S Baranov
- Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow (Russia).
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13
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Egloff J, Ranocchiari M, Schira A, Schotes C, Mezzetti A. Highly Enantioselective Ruthenium/PNNP-Catalyzed Imine Aziridination: Evidence of Carbene Transfer from a Diazoester Complex. Organometallics 2013. [DOI: 10.1021/om400735p] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joël Egloff
- Department of Chemistry and Applied
Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Marco Ranocchiari
- Department of Chemistry and Applied
Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Amata Schira
- Department of Chemistry and Applied
Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Christoph Schotes
- Department of Chemistry and Applied
Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Antonio Mezzetti
- Department of Chemistry and Applied
Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland
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14
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Baranov MS, Lukyanov KA, Yampolsky IV. Synthesis of the chromophores of fluorescent proteins and their analogs. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2013; 39:255-76. [DOI: 10.1134/s1068162013030047] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Lee CY, Chen YC, Lin HC, Jhong Y, Chang CW, Tsai CH, Kao CL, Chien TC. Facile synthesis of 4-arylidene-5-imidazolinones as synthetic analogs of fluorescent protein chromophore. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.04.102] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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16
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Tolbert LM, Baldridge A, Kowalik J, Solntsev KM. Collapse and recovery of green fluorescent protein chromophore emission through topological effects. Acc Chem Res 2012; 45:171-81. [PMID: 21861536 DOI: 10.1021/ar2000925] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Housed within the 11-stranded β-barrel of the green fluorescent protein (GFP) is the arylideneimidazolidinone (AMI) chromophore, the component responsible for fluorescence. This class of small-molecule chromophore has drawn significant attention for its remarkable photophysical and photochemical properties, both within the intact protein and after its denaturation. All of the proteins so far isolated that have visible light fluorescence have been found to contain an AMI chromophore. These proteins comprise an extensive rainbow, ranging from GFP, which contains the simplest chromophore, p-hydroxybenzylideneimidazolidinone (p-HOBDI), to proteins having molecules with longer conjugation lengths and a variety of intraprotein interactions. The fluorescence invariably almost vanishes upon removal of the protective β-barrel. The role of the barrel in hindering internal conversion has been the subject of numerous studies, especially in our laboratories and those of our collaborators. A better understanding of these chromophores has been facilitated by the development of numerous synthetic protocols. These syntheses, which commonly use the Erlenmeyer azlactone method, have evolved in recent years with the development of a [2 + 3] cycloaddition exploited in our laboratory. The synthetic AMI chromophores have allowed delineation of the complex photophysics of GFP and its derivatives. Upon denaturation, AMI chromophores are marked by 4 orders of magnitude of diminution in emission quantum yield (EQY). This result is attributed to internal conversion resulting from conformational freedom in the released chromophore, which is not allowed within the restrictive β-barrel. To date, the photophysical properties of the AMI chromophore remain elusive and have been attributed to a variety of mechanisms, including cis-trans isomerization, triplet formation, hula twisting, and proton transfer. Advanced studies involving gas-phase behavior, solvent effects, and protonation states have significantly increased our understanding of the chromophore photophysics, but a comprehensive picture is only slowly emerging. Most importantly, mechanisms in structurally defined chromophores may provide clues as to the origin of the "blinking" behavior of the fluorescent proteins themselves. One approach to examining the effect of conformational freedom on rapid internal conversion of the chromophores is to restrict the molecules, both through structural modifications and through adjustments of the supramolecular systems. We thus include here a discussion of studies involving the crystalline state, inclusion within natural protein-binding pockets, complexation with metal ions, and sequestration within synthetic cavities; all of this research affirms the role of restricting conformational freedom in partially restoring the EQY. Additionally, new photochemistry is observed within these restricted systems. Many of the studies carried out in our laboratories show promise for these molecules to be adapted as molecular probes, wherein inclusion turns on the fluorescence and provides a signaling mechanism. In this Account, we present an overview of the AMI chromophores, including synthesis, overall photophysics, and supramolecular behavior. A significant amount of work remains for researchers to fully understand the properties of these chromophores, but important progress achieved thus far in photophysics and photochemistry is underscored here.
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Affiliation(s)
- Laren M. Tolbert
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, United States
| | - Anthony Baldridge
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, United States
| | - Janusz Kowalik
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, United States
| | - Kyril M. Solntsev
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, United States
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Baldridge A, Amador A, Tolbert LM. Fluorescence turn on by cholate aggregates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:3271-3274. [PMID: 21395254 DOI: 10.1021/la2003244] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bile salts, including sodium cholate (NaCh), are amphiphilic molecules with a concave hydrophilic side and a convex hydrophobic side. By forming aggregates in aqueous solution, these natural surfactants fulfill vital biological roles in the solubilization of cholesterol, lipids, and fat-soluble vitamins and thus are involved in the transport and absorption of important biological molecules. Following our success with the encapsulation of fluorescent protein chromophore (FP) analogs by synthetic hydrophobic and hydrophilic hosts, based upon substitution patterns, we now report the binding and turn on of other analogs by bile salt aggregates, observations which may lead to new tools for studying trafficking in these important systems.
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Affiliation(s)
- Anthony Baldridge
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States
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Baldridge A, Samanta SR, Jayaraj N, Ramamurthy V, Tolbert LM. Steric and electronic effects in capsule-confined green fluorescent protein chromophores. J Am Chem Soc 2010; 133:712-5. [PMID: 21174415 DOI: 10.1021/ja1094606] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The turn-on of emission in fluorescent protein chromophores sequestered in an "octaacid" capsule is controlled by stereoelectronic effects described by a linear free energy relationship. The stereochemical effects are governed by both the positions and volumes of the aryl substituents, while the electronic effects, including ortho effects, can be treated with Hammett σ parameters. The use of substituent volumes rather than A values reflects packing of the molecule within the confines of the capsule.
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Affiliation(s)
- Anthony Baldridge
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, United States
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Baldridge A, Samanta SR, Jayaraj N, Ramamurthy V, Tolbert LM. Activation of Fluorescent Protein Chromophores by Encapsulation. J Am Chem Soc 2010; 132:1498-9. [DOI: 10.1021/ja908870k] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anthony Baldridge
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, and Department of Chemistry, University of Miami, Coral Gables, Florida 33146
| | - Shampa R. Samanta
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, and Department of Chemistry, University of Miami, Coral Gables, Florida 33146
| | - Nithyanandhan Jayaraj
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, and Department of Chemistry, University of Miami, Coral Gables, Florida 33146
| | - V. Ramamurthy
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, and Department of Chemistry, University of Miami, Coral Gables, Florida 33146
| | - Laren M. Tolbert
- School of Chemistry and Biochemistry, 901 Atlantic Drive, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, and Department of Chemistry, University of Miami, Coral Gables, Florida 33146
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Wang L, Ma H. Zinc complexes supported by multidentate aminophenolate ligands: synthesis, structure and catalysis in ring-opening polymerization of rac-lactide. Dalton Trans 2010; 39:7897-910. [DOI: 10.1039/c0dt00250j] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Candeias NR, Branco LC, Gois PMP, Afonso CAM, Trindade AF. More Sustainable Approaches for the Synthesis of N-Based Heterocycles. Chem Rev 2009; 109:2703-802. [DOI: 10.1021/cr800462w] [Citation(s) in RCA: 292] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nuno R. Candeias
- Centro de Química-Física Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Química e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Luís C. Branco
- Centro de Química-Física Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Química e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Pedro M. P. Gois
- Centro de Química-Física Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Química e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Carlos A. M. Afonso
- Centro de Química-Física Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Química e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Alexandre F. Trindade
- Centro de Química-Física Molecular (CQFM) and Institute of Nanosciences and Nanotechnology (IN), Departamento de Engenharia Química e Biológica, Instituto Superior Técnico, 1049-001 Lisboa, Portugal, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal, and iMed.UL, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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Carreaux F, Pierre Bazureau J, Debdab M, Renault S, Eid S, Lozach O, Meijer L. An Efficient Method for the Preparation of New Analogs of Leucettamine B under Solvent-Free Microwave Irradiation. HETEROCYCLES 2009. [DOI: 10.3987/com-08-11594] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Kim Y, Kim J, Park SB. Regioselective Synthesis of Tetrasubstituted Pyrroles by 1,3-Dipolar Cycloaddition and Spontaneous Decarboxylation. Org Lett 2008; 11:17-20. [DOI: 10.1021/ol8022193] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yongju Kim
- Department of Chemistry, Seoul National University, Seoul 151-747, Korea
| | - Jonghoon Kim
- Department of Chemistry, Seoul National University, Seoul 151-747, Korea
| | - Seung Bum Park
- Department of Chemistry, Seoul National University, Seoul 151-747, Korea
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Renault S, Bertrand S, Carreaux F, Bazureau JP. Parallel Solution-Phase Synthesis of 2-Alkylthio-5-arylidene-3,5-dihydro-4H-imidazol-4-one by One-Pot Three-Component Domino Reaction. ACTA ACUST UNITED AC 2007; 9:935-42. [PMID: 17822301 DOI: 10.1021/cc070022i] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A practical protocol for the preparation of a parallel solution-phase library of 5-arylidene imidazolone is reported. Target compounds were obtained in good yield, stereoselectively, and purity by one-pot domino reaction from various thiohydantoines, arylaldimines, and halogenoalkanes. Purification of the final products by recrystallization with a mixture of pentane/ethanol allowed simple isolation of the 17 components of the array.
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Affiliation(s)
- Stéven Renault
- Laboratoire Sciences Chimiques de Rennes, UMR CNRS 6226, Groupe Ingénierie Chimique et Molécules pour le Vivant, Université de Rennes 1, Bat. 10A, Campus de Beaulieu, Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France
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Pospíšil J, Potáček M. Microwave-assisted solvent-free intramolecular 1,3-dipolar cycloaddition reactions leading to hexahydrochromeno[4,3-b]pyrroles: scope and limitations. Tetrahedron 2007. [DOI: 10.1016/j.tet.2006.10.074] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Microwave-assisted solvent-free heterocyclic synthesis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2005. [DOI: 10.1016/j.jphotochemrev.2005.07.001] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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El Ashry E, Ramadan E, Kassem A, Hagar M. Microwave Irradiation for Accelerating Organic Reactions. Part I: Three-, Four- and Five-Membered Heterocycles. ADVANCES IN HETEROCYCLIC CHEMISTRY 2005. [DOI: 10.1016/s0065-2725(04)88001-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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de la Hoz A, Díaz-Ortis A, Moreno A, Langa F. Cycloadditions under Microwave Irradiation Conditions: Methods and Applications. European J Org Chem 2000. [DOI: 10.1002/1099-0690(200011)2000:22%3c3659::aid-ejoc3659%3e3.0.co;2-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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de la Hoz A, Díaz-Ortis A, Moreno A, Langa F. Cycloadditions under Microwave Irradiation Conditions: Methods and Applications. European J Org Chem 2000. [DOI: 10.1002/1099-0690(200011)2000:22<3659::aid-ejoc3659>3.0.co;2-0] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Jouneau S, Bazureau JP. Solvent free aza-annulation using 4-dimethylamino 2-aza-1,3-dienes as γ-dielectrophiles for a new synthesis of imidazole-4-carboxylates. Tetrahedron Lett 1999. [DOI: 10.1016/s0040-4039(99)01696-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Arrieta A, Ramón Carrillo J, Cossío FP, Díaz-Ortiz A, JoséGómez-Escalonilla M, de la Hoz A, Langa F, Moreno A. Efficient tautomerization hydrazone-azomethine imine under microwave irradiation. Synthesis of [4,3′] and [5,3′]bipyrazoles. Tetrahedron 1998. [DOI: 10.1016/s0040-4020(98)00798-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Jolivet-Fouchet S, Hamelin J, Texier-Boullet F, Toupet L, Jacquault P. Novel pathway to 1-aminopyrroles and other nitrogen heterocycles from glyoxal monohydrazones and acylated active methylene compounds in solvent-free reactions under microwave irradiation. Tetrahedron 1998. [DOI: 10.1016/s0040-4020(98)00159-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Lerestif JM, Toupet L, Sinbandhit S, Tonnard F, Bazureau JP, Hamelin J. A new route to 2-oxazolines, bis-oxazolines, and 2-imidazoline-5-ones from imidates using solvent-free cycloadditions: Synthesis, chemical properties, and PM3 MO calculations. Tetrahedron 1997. [DOI: 10.1016/s0040-4020(97)00295-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Unusual and stereoselective ring closure of unsaturated monohydrazones with β-ketoesters in a solvent-free reaction. Tetrahedron 1996. [DOI: 10.1016/0040-4020(96)00177-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rahmouni M, Derdour A, Bazureau JP, Hamelin J. A New Access to 2,3-Dihydro Imidazo [1,2-c] Pyrimidines. SYNTHETIC COMMUN 1996. [DOI: 10.1080/00397919608003636] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Morel F, Lerestif JM, Bazureau JP, Hamelin J, Tonnard F. Acid-induced dimerization of imidates derived from glycine: Synthesis of methylN-(1,2,5-trisubstituted-4-imidazoyl)glycinates. HETEROATOM CHEMISTRY 1996. [DOI: 10.1002/(sici)1098-1071(199605)7:3<187::aid-hc5>3.0.co;2-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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