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Defant A, Carloni G, Innocenti N, Trobec T, Frangež R, Sepčić K, Mancini I. Structural Insights into the Marine Alkaloid Discorhabdin G as a Scaffold towards New Acetylcholinesterase Inhibitors. Mar Drugs 2024; 22:173. [PMID: 38667790 PMCID: PMC11051419 DOI: 10.3390/md22040173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
In this study, Antarctic Latrunculia sponge-derived discorhabdin G was considered a hit for developing potential lead compounds acting as cholinesterase inhibitors. The hypothesis on the pharmacophore moiety suggested through molecular docking allowed us to simplify the structure of the metabolite. ADME prediction and drug-likeness consideration provided valuable support in selecting 5-methyl-2H-benzo[h]imidazo[1,5,4-de]quinoxalin-7(3H)-one as a candidate molecule. It was synthesized in a four-step sequence starting from 2,3-dichloronaphthalene-1,4-dione and evaluated as an inhibitor of electric eel acetylcholinesterase (eeAChE), human recombinant AChE (hAChE), and horse serum butyrylcholinesterase (BChE), together with other analogs obtained by the same synthesis. The candidate molecule showed a slightly lower inhibitory potential against eeAChE but better inhibitory activity against hAChE than discorhabdin G, with a higher selectivity for AChEs than for BChE. It acted as a reversible competitive inhibitor, as previously observed for the natural alkaloid. The findings from the in vitro assay were relatively consistent with the data available from the AutoDock Vina and Protein-Ligand ANTSystem (PLANTS) calculations.
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Affiliation(s)
- Andrea Defant
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento, Italy; (G.C.); (N.I.)
| | - Giacomo Carloni
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento, Italy; (G.C.); (N.I.)
- Unit of Structural Microbiology, Pasteur Institute, CNRS, University of Paris City, 75015 Paris, France
| | - Nicole Innocenti
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento, Italy; (G.C.); (N.I.)
| | - Tomaž Trobec
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (T.T.); (R.F.)
| | - Robert Frangež
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (T.T.); (R.F.)
| | - Kristina Sepčić
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia;
| | - Ines Mancini
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, Via Sommarive 14, 38123 Trento, Italy; (G.C.); (N.I.)
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2
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Boshoff HI, Malhotra N, Barry CE, Oh S. The Antitubercular Activities of Natural Products with Fused-Nitrogen-Containing Heterocycles. Pharmaceuticals (Basel) 2024; 17:211. [PMID: 38399426 PMCID: PMC10892018 DOI: 10.3390/ph17020211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/02/2024] [Accepted: 02/04/2024] [Indexed: 02/25/2024] Open
Abstract
Tuberculosis (TB) is notorious as the leading cause of death worldwide due to a single infectious entity and its causative agent, Mycobacterium tuberculosis (Mtb), has been able to evolve resistance to all existing drugs in the treatment arsenal complicating disease management programs. In drug discovery efforts, natural products are important starting points in generating novel scaffolds that have evolved to specifically bind to vulnerable targets not only in pathogens such as Mtb, but also in mammalian targets associated with human diseases. Structural diversity is one of the most attractive features of natural products. This review provides a summary of fused-nitrogen-containing heterocycles found in the natural products reported in the literature that are known to have antitubercular activities. The structurally targeted natural products discussed in this review could provide a revealing insight into novel chemical aspects with novel biological functions for TB drug discovery efforts.
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Affiliation(s)
| | | | | | - Sangmi Oh
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD 20892, USA; (H.I.B.); (N.M.); (C.E.B.III)
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3
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Current Perspectives on Pyrroloiminoquinones: Distribution, Biosynthesis and Drug Discovery Potential. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248724. [PMID: 36557854 PMCID: PMC9787360 DOI: 10.3390/molecules27248724] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022]
Abstract
Pyrroloiminoquinones are a group of cytotoxic alkaloids most commonly isolated from marine sponges. Structurally, they are based on a tricyclic pyrrolo[4,3,2-de]quinoline core and encompass marine natural products such as makaluvamines, tsitsikammamines and discorhabdins. These diverse compounds are known to exhibit a broad spectrum of biological activities including anticancer, antiplasmodial, antimicrobial, antifungal and antiviral activities as well as the inhibition of several key cellular enzymes. The resurgence of interest in pyrroloiminoquinones and the convoluted understanding regarding their biological activities have prompted this review. Herein, we provided a concise summary of key findings and recent developments pertaining to their structural diversity, distribution, biogenesis, and their potential as chemical probes for drug development, including a discussion of promising synthetic analogs.
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Dactylospongia elegans—A Promising Drug Source: Metabolites, Bioactivities, Biosynthesis, Synthesis, and Structural-Activity Relationship. Mar Drugs 2022; 20:md20040221. [PMID: 35447894 PMCID: PMC9033123 DOI: 10.3390/md20040221] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 03/17/2022] [Accepted: 03/22/2022] [Indexed: 02/07/2023] Open
Abstract
Marine environment has been identified as a huge reservoir of novel biometabolites that are beneficial for medical treatments, as well as improving human health and well-being. Sponges have been highlighted as one of the most interesting phyla as new metabolites producers. Dactylospongia elegans Thiele (Thorectidae) is a wealth pool of various classes of sesquiterpenes, including hydroquinones, quinones, and tetronic acid derivatives. These metabolites possessed a wide array of potent bioactivities such as antitumor, cytotoxicity, antibacterial, and anti-inflammatory. In the current work, the reported metabolites from D. elegans have been reviewed, including their bioactivities, biosynthesis, and synthesis, as well as the structural-activity relationship studies. Reviewing the reported studies revealed that these metabolites could contribute to new drug discovery, however, further mechanistic and in vivo studies of these metabolites are needed.
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Noro T, Sakata J, Tokuyama H. Synthetic studies on discorhabdin V: Construction of the A–F hexacyclic framework. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Bhattacharya A, Thirupathi A, Natarajan P, Peruncheralathan S. Chemoselective Ullmann Reaction of α-Trisubstituted Thioamides: Synthesis of Novel 2-Iminobenzothiolanes. ACS OMEGA 2021; 6:21169-21180. [PMID: 34423225 PMCID: PMC8375098 DOI: 10.1021/acsomega.1c03410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
New classes of unexplored benzo[b]thiolanes are synthesized from trisubstituted thioamides through copper-catalyzed intramolecular S-arylation of thioamides for the first time. This method provides good to excellent yields with fully controlled chemoselectivity. Unusually, iminobenzo[b]thiolanes are very stable under mild acidic conditions. A plausible mechanism is proposed for the chemoselective S-arylation process.
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Leite TOC, Novais JS, de Carvalho BLC, Ferreira VF, Miceli LA, Fraga L, Abrahim-Vieira B, Rodrigues CR, Sá Figueiredo AM, Castro HC, Cunha AC. Synthesis, In Vitro and In Silico Studies of Indolequinone Derivatives against Clinically Relevant Bacterial Pathogens. Curr Top Med Chem 2020; 20:192-208. [DOI: 10.2174/1568026620666191223110518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/05/2019] [Accepted: 11/25/2019] [Indexed: 01/09/2023]
Abstract
Background:
According to the World Health Organization, antimicrobial resistance is one of
the most important public health threats of the 21st century. Therefore, there is an urgent need for the
development of antimicrobial agents with new mechanism of action, especially those capable of evading
known resistance mechanisms.
Objective:
We described the synthesis, in vitro antimicrobial evaluation, and in silico analysis of a series
of 1H-indole-4,7-dione derivatives.
Methods:
The new series of 1H-indole-4,7-diones was prepared with good yield by using a copper(II)-
mediated reaction between bromoquinone and β-enamino ketones bearing alkyl or phenyl groups attached
to the nitrogen atom. The antimicrobial potential of indole derivatives was assessed. Molecular
docking studies were also performed using AutoDock 4.2 for Windows. Characterization of all compounds
was confirmed by one- and two-dimensional NMR techniques 1H and 13C NMR spectra [1H, 13C
– APT, 1H x 1H – COSY, HSQC and HMBC], IR and mass spectrometry analysis.
Results:
Several indolequinone compounds showed effective antimicrobial profile against Grampositive
(MIC = 16 µg.mL-1) and Gram-negative bacteria (MIC = 8 µg.mL-1) similar to antimicrobials
current on the market. The 3-acetyl-1-(2,5-dimethylphenyl)-1H-indole-4,7-dione derivative exhibited an
important effect against different biofilm stages formed by a serious hospital life-threatening resistant
strain of Methicillin-Resistant Staphylococcus aureus (MRSA). A hemocompatibility profile analysis
based on in vitro hemolysis assays revealed the low toxicity effects of this new series. Indeed, in silico
studies showed a good pharmacokinetics and toxicological profiles for all indolequinone derivatives,
reinforcing their feasibility to display a promising oral bioavailability. An elucidation of the promising
indolequinone derivatives binding mode was achieved, showing interactions with important sites to biological
activity of S. aureus DNA gyrase. These results highlighted 3-acetyl-1-(2-hydroxyethyl)-1Hindole-
4,7-dione derivative as broad-spectrum antimicrobial prototype to be further explored for treating
bacterial infections.
Conclusion:
The highly substituted indolequinones were obtained in moderate to good yields. The
pharmacological study indicated that these compounds should be exploited in the search for a leading
substance in a project aimed at obtaining new antimicrobials effective against Gram-negative bacteria.
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Affiliation(s)
- Talita Odriane Custodio Leite
- Universidade Federal Fluminense, Instituto de Quimica, Departamento de Quimica Organica, Programa de Pos- Graduacao em Quimica, 24020-141, Niteroi, Rio de Janeiro, Brazil
| | - Juliana Silva Novais
- Universidade Federal Fluminense, Programas de Pos-Graduacao em Patologia (HUAP) e em Ciencias e Biotecnologia (PPBI), 24020-150, Niteroi, Rio de Janeiro, Brazil
| | - Beatriz Lima Cosenza de Carvalho
- Universidade Federal do Rio de Janeiro, Instituto de Quimica, Departamento de Quimica Organica, 21941-909, Rio de Janeiro, Brazil
| | - Vitor Francisco Ferreira
- Universidade Federal Fluminense, Faculdade de Farmácia, 24241-000, Departamento de Tecnologia Farmaceutica, Niteroi, Rio de Janeiro, Brazil
| | - Leonardo Alves Miceli
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Professor Paulo de Goes, Programa de Pos-Graduacao em Ciencias Farmaceuticas e Faculdade de Farmacia, 21941-902, Rio de Janeiro, Brazil
| | - Letícia Fraga
- Universidade Federal do Rio de Janeiro, Laboratorio de Modelagem Molecular e QSAR (MODMOLQSAR), Faculdade de Farmacia, 21941-902, Rio de Janeiro, Brazil
| | - Bárbara Abrahim-Vieira
- Universidade Federal do Rio de Janeiro, Laboratorio de Modelagem Molecular e QSAR (MODMOLQSAR), Faculdade de Farmacia, 21941-902, Rio de Janeiro, Brazil
| | - Carlos Rangel Rodrigues
- Universidade Federal do Rio de Janeiro, Programa de Pos-Graduacao em Ciências Farmaceuticas da Faculdade de Farmacia, 21941-902, Rio de Janeiro, Brazil
| | - Agnes Marie Sá Figueiredo
- Universidade Federal do Rio de Janeiro, Laboratorio de Modelagem Molecular e QSAR (MODMOLQSAR), Faculdade de Farmacia, 21941-902, Rio de Janeiro, Brazil
| | - Helena Carla Castro
- Universidade Federal Fluminense, Programas de Pos-Graduacao em Patologia (HUAP) e em Ciencias e Biotecnologia (PPBI), 24020-150, Niteroi, Rio de Janeiro, Brazil
| | - Anna Claudia Cunha
- Universidade Federal Fluminense, Instituto de Quimica, Departamento de Quimica Organica, Programa de Pos- Graduacao em Quimica, 24020-141, Niteroi, Rio de Janeiro, Brazil
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Smith MW, Falk ID, Ikemoto H, Burns NZ. A Convenient C-H Functionalization Platform for Pyrroloiminoquinone Alkaloid Synthesis. Tetrahedron 2019; 75:3366-3370. [PMID: 31889735 DOI: 10.1016/j.tet.2019.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pyrroloiminoquinone alkaloids represent a structurally intriguing class of natural products that display an array of useful biological properties. Here, we present a versatile and scalable platform for the synthesis of this diverse family - and in particular the antitumor discorhabdins - built upon sequential selective C-H functionalization of tryptamine. The utility of this strategy is showcased through short formal syntheses of damirones A-C, makaluvamines D and I, and discorhadbin E. Additionally, we describe efforts to develop the first catalytic asymmetric entry to the discorhabdin subclass.
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Affiliation(s)
- Myles W Smith
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Isaac D Falk
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Hideya Ikemoto
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Noah Z Burns
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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9
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Kärkäs MD. Electrochemical strategies for C-H functionalization and C-N bond formation. Chem Soc Rev 2018; 47:5786-5865. [PMID: 29911724 DOI: 10.1039/c7cs00619e] [Citation(s) in RCA: 582] [Impact Index Per Article: 97.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Conventional methods for carrying out carbon-hydrogen functionalization and carbon-nitrogen bond formation are typically conducted at elevated temperatures, and rely on expensive catalysts as well as the use of stoichiometric, and perhaps toxic, oxidants. In this regard, electrochemical synthesis has recently been recognized as a sustainable and scalable strategy for the construction of challenging carbon-carbon and carbon-heteroatom bonds. Here, electrosynthesis has proven to be an environmentally benign, highly effective and versatile platform for achieving a wide range of nonclassical bond disconnections via generation of radical intermediates under mild reaction conditions. This review provides an overview on the use of anodic electrochemical methods for expediting the development of carbon-hydrogen functionalization and carbon-nitrogen bond formation strategies. Emphasis is placed on methodology development and mechanistic insight and aims to provide inspiration for future synthetic applications in the field of electrosynthesis.
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Affiliation(s)
- Markus D Kärkäs
- Department of Chemistry, Organic Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
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10
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Preclinical Evaluation of Discorhabdins in Antiangiogenic and Antitumor Models. Mar Drugs 2018; 16:md16070241. [PMID: 30029505 PMCID: PMC6071056 DOI: 10.3390/md16070241] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/09/2018] [Accepted: 07/16/2018] [Indexed: 12/12/2022] Open
Abstract
Elements of the hypoxia inducible factor (HIF) transcriptional system, a key regulator of the cellular hypoxic response, are up-regulated in a range of cancer cells. HIF is fundamentally involved in tumor angiogenesis, invasion, and energy metabolism. Inhibition of the transcriptional activity of HIF may be of therapeutic benefit to cancer patients. We recently described the identification of two marine pyrroloiminoquinone alkaloids with potent activity in inhibiting the interaction between the oncogenic transcription factor HIF-1α and the coactivator protein p300. Herein, we present further characterization data for these two screening hits: discorhabdin H (1) and discorhabdin L (2), with a specific focus on their anti-angiogenic and anti-tumor effects. We demonstrated that only discorhabdin L (2) possesses excellent anti-angiogenic activity in inhibiting endothelial cell proliferation and tube formation, as well as decreasing microvessel outgrowth in the ex vivo rat aortic ring assay. We further showed that discorhabdin L (2) significantly inhibits in vivo prostate tumor growth in a LNCaP xenograft model. In conclusion, our findings suggest that discorhabdin L (2) represents a promising HIF-1α inhibitor worthy of further drug development.
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11
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Mhd Bakri Y, Syed Abd Azizz SS, Abdul Talib M, Mohamed F. The antimicrobial activity of plants in the vicinity of a geothermal area in Perak, Malaysia. F1000Res 2017; 6:941. [DOI: 10.12688/f1000research.11858.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/02/2023] Open
Abstract
We wish to report the study of the antimicrobial activity of plants collected in the vicinity of a geothermal area in Perak, Malaysia. This is the first report of these species in the vicinity of thextis geothermal area. The plants are Cleome icosandra, locally known as Maman Pasir of the family Cleomaceae, and Stachytarpheta species of the family Lamiaceae. Both are subshrubs and are believed to have specific biological activities as a result of living in such extreme areas. Methanol extracts of both plants revealed no antimicrobial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa.
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12
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Botić T, Defant A, Zanini P, Žužek MC, Frangež R, Janussen D, Kersken D, Knez Ž, Mancini I, Sepčić K. Discorhabdin alkaloids from Antarctic Latrunculia spp. sponges as a new class of cholinesterase inhibitors. Eur J Med Chem 2017; 136:294-304. [PMID: 28505534 DOI: 10.1016/j.ejmech.2017.05.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 05/04/2017] [Accepted: 05/05/2017] [Indexed: 11/19/2022]
Abstract
The brominated pyrroloiminoquinone alkaloids discorhabdins B, L and G and 3-dihydro-7,8- dehydrodiscorhabdin C, isolated from methanol extracts of two specimens of Latrunculia sp. sponges collected near the Antarctic Peninsula, are here demonstrated for the first time to be reversible competitive inhibitors of cholinesterases. They showed Ki for electric eel acetylcholinesterase of 1.6-15.0 μM, for recombinant human acetylcholinesterase of 22.8-98.0 μM, and for horse serum butyrylcholinesterase of 5.0-76.0 μM. These values are promising when compared to the current cholinesterase inhibitors used for treatment of patients with Alzheimer's disease, to counteract the acetylcholine deficiency in the brain. Good correlation was obtained between IC50 data and results by molecular docking calculation on the binding interactions within the acetylcholinesterase active site, which also indicated the moieties in discorhabdin structures involved. To avoid unwanted peripheral side effects that can appear in patients using some acetylcholinesterase inhibitors, electrophysiological experiments were carried out on one of the most active of these compounds, discorhabdin G, which confirmed that it had no detectable undesirable effects on neuromuscular transmission and skeletal muscle function. These findings are promising for development of cholinesterase inhibitors based on the scaffold of discorhabdins, as potential new agents for treatment of patients with Alzheimer's disease.
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Affiliation(s)
- Tanja Botić
- Laboratory for Separation Processes and Product Design, Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Andrea Defant
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, via Sommarive, 14, I-38123 Povo-Trento, Italy
| | - Pietro Zanini
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, via Sommarive, 14, I-38123 Povo-Trento, Italy
| | - Monika Cecilija Žužek
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, Slovenia
| | - Robert Frangež
- Institute of Preclinical Sciences, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, Slovenia
| | - Dorte Janussen
- Marine Zoology Department, Senckenberg Research Institute and Nature Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany
| | - Daniel Kersken
- Marine Zoology Department, Senckenberg Research Institute and Nature Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany
| | - Željko Knez
- Laboratory for Separation Processes and Product Design, Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Ines Mancini
- Laboratory of Bioorganic Chemistry, Department of Physics, University of Trento, via Sommarive, 14, I-38123 Povo-Trento, Italy.
| | - Kristina Sepčić
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia.
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Walton JC. Synthetic Strategies for 5- and 6-Membered Ring Azaheterocycles Facilitated by Iminyl Radicals. Molecules 2016; 21:molecules21050660. [PMID: 27213311 PMCID: PMC6273063 DOI: 10.3390/molecules21050660] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/11/2016] [Accepted: 05/16/2016] [Indexed: 01/09/2023] Open
Abstract
The totality of chemical space is so immense that only a small fraction can ever be explored. Computational searching has indicated that bioactivity is associated with a comparatively small number of ring-containing structures. Pyrrole, indole, pyridine, quinoline, quinazoline and related 6-membered ring-containing aza-arenes figure prominently. This review focuses on the search for fast, efficient and environmentally friendly preparative methods for these rings with specific emphasis on iminyl radical-mediated procedures. Oxime derivatives, particularly oxime esters and oxime ethers, are attractive precursors for these radicals. Their use is described in conventional thermolytic, microwave-assisted and UV-vis based preparative procedures. Photoredox-catalyzed protocols involving designer oxime ethers are also covered. Choice can be made amongst these synthetic strategies for a wide variety of 5- and 6-membered ring heterocycles including phenanthridine and related aza-arenes. Applications to selected natural products and bioactive molecules, including trispheridine, vasconine, luotonin A and rutaecarpine, are included.
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Affiliation(s)
- John C Walton
- University of St. Andrews, EaStCHEM School of Chemistry, St. Andrews, Fife KY16 9ST, UK.
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14
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Wang W, Nijampatnam B, Velu SE, Zhang R. Discovery and development of synthetic tricyclic pyrroloquinone (TPQ) alkaloid analogs for human cancer therapy. Front Chem Sci Eng 2016. [DOI: 10.1007/s11705-016-1562-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Abstract
Covering: 2009 to 2013. This review covers the 188 novel marine natural products described since 2008, from deep-water (50->5000 m) marine fauna including bryozoa, chordata, cnidaria, echinodermata, microorganisms, mollusca and porifera. The structures of the new compounds and details of the source organism, depth of collection and country of origin are presented, along with any relevant biological activities of the metabolites. Where reported, synthetic studies on the deep-sea natural products have also been included. Most strikingly, 75% of the compounds were reported to possess bioactivity, with almost half exhibiting low micromolar cytotoxicity towards a range of human cancer cell lines, along with a significant increase in the number of microbial deep-sea natural products reported.
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Affiliation(s)
- Danielle Skropeta
- School of Chemistry, University of Wollongong, Wollongong, NSW 2500, Australia
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16
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Abstract
Review of deep-sea natural products covering the five-year period 2009–2013.
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Affiliation(s)
| | - Liangqian Wei
- Centre of Medicinal Chemistry
- University of Wollongong
- Wollongong, Australia
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17
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Hu JF, Fan H, Xiong J, Wu SB. Discorhabdins and Pyrroloiminoquinone-Related Alkaloids. Chem Rev 2011; 111:5465-91. [DOI: 10.1021/cr100435g] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jin-Feng Hu
- Department of Natural Products Chemistry, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai 201203, China
| | - Hui Fan
- Department of Natural Products for Chemical Genetic Research, Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, No. 3663 Zhongshan Road N, Shanghai 200062, China
| | - Juan Xiong
- Department of Natural Products Chemistry, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai 201203, China
| | - Shi-Biao Wu
- Department of Natural Products for Chemical Genetic Research, Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, No. 3663 Zhongshan Road N, Shanghai 200062, China
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18
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Kita Y, Dohi T, Morimoto K. Hypervalent Iodine Induced Metal-Free C-H Cross Couplings to Biaryls. J SYN ORG CHEM JPN 2011. [DOI: 10.5059/yukigoseikyokaishi.69.1241] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yasuyuki Kita
- College of Pharmaceutical Sciences, Ritsumeikan University
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