551
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De Simone F, Gertsch J, Waser J. Catalytic selective cyclizations of aminocyclopropanes: formal synthesis of aspidospermidine and total synthesis of goniomitine. Angew Chem Int Ed Engl 2011; 49:5767-70. [PMID: 20533490 DOI: 10.1002/anie.201001853] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Filippo De Simone
- Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland
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552
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Tae HS, Hines J, Schneekloth AR, Crews CM. Total synthesis and biological evaluation of tyroscherin. Org Lett 2011; 12:4308-11. [PMID: 20831175 DOI: 10.1021/ol101801u] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The efficient synthesis and biological evaluation of both the reported and revised structures of tyroscherin have been achieved. Central to our synthesis is a cross metathesis reaction that generated the trans-olefin regioselectively. This synthetic strategy enabled the facile manipulation of tyroscherin stereochemistry, facilitating the generation of all 16 tyroscherin diastereomers and a photoactivatable tyroscherin-based affinity probe for future mode of action studies.
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Affiliation(s)
- Hyun Seop Tae
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06511, USA
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553
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Kusari S, Spiteller M. Are we ready for industrial production of bioactive plant secondary metabolites utilizing endophytes? Nat Prod Rep 2011; 28:1203-7. [DOI: 10.1039/c1np00030f] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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554
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Tan JL, Zon LI. Chemical screening in zebrafish for novel biological and therapeutic discovery. Methods Cell Biol 2011; 105:493-516. [PMID: 21951544 DOI: 10.1016/b978-0-12-381320-6.00021-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Zebrafish chemical screening allows for an in vivo assessment of small molecule modulation of biological processes. Compound toxicities, chemical alterations by metabolism, pharmacokinetic and pharmacodynamic properties, and modulation of cell niches can be studied with this method. Furthermore, zebrafish screening is straightforward and cost-effective. Zebrafish provide an invaluable platform for novel therapeutic discovery through chemical screening.
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Affiliation(s)
- Justin L Tan
- Stem Cell Program and Division of Hematology and Oncology, Children’s Hospital Boston, Dana-Farber Cancer Institute, Howard Hughes Medical Institute and Harvard Medical School, Boston, Massachusetts, USA
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555
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Anderl T, Nicolas L, Münkemer J, Baro A, Sasse F, Steinmetz H, Jansen R, Höfle G, Taylor RE, Laschat S. Gephyronic acid, a missing link between polyketide inhibitors of eukaryotic protein synthesis (part II): Total synthesis of gephyronic acid. Angew Chem Int Ed Engl 2010; 50:942-5. [PMID: 21246697 DOI: 10.1002/anie.201005605] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Indexed: 11/10/2022]
Affiliation(s)
- Timo Anderl
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
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556
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Ghosh AK. Capturing the essence of organic synthesis: from bioactive natural products to designed molecules in today's medicine. J Org Chem 2010; 75:7967-89. [PMID: 20936876 PMCID: PMC2993809 DOI: 10.1021/jo101606g] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this Perspective, I outline my group's research involving the chemical syntheses of medicinally important natural products, exploration of their bioactivity, and the development of new asymmetric carbon-carbon bond-forming reactions. This paper also highlights our approach to molecular design and synthesis of conceptually novel inhibitors against target proteins involved in the pathogenesis of human diseases, including AIDS and Alzheimer's disease.
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Affiliation(s)
- Arun K Ghosh
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, USA.
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557
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Orth R, Böttcher T, Sieber SA. The biological targets of acivicin inspired 3-chloro- and 3-bromodihydroisoxazole scaffolds. Chem Commun (Camb) 2010; 46:8475-7. [PMID: 20936198 DOI: 10.1039/c0cc02825h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Target analysis of acivicin derived 3-halodihydroisoxazoles scaffolds in living non-pathogenic and pathogenic bacteria.
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Affiliation(s)
- Ronald Orth
- Center for Integrated Protein Science Munich CIPSM, Department of Chemistry, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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558
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559
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Snaddon TN, Buchgraber P, Schulthoff S, Wirtz C, Mynott R, Fürstner A. Total Synthesis of Berkelic Acid. Chemistry 2010; 16:12133-40. [DOI: 10.1002/chem.201001133] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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560
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Xu WM, He J, Yu MQ, Shen GX. Site-Selective Modification of Vitamin D Analogue (Deltanoid) through a Resin-Based Version of Organoselenium 2,3-Sigmatropic Rearrangement. Org Lett 2010; 12:4431-3. [DOI: 10.1021/ol101879k] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wei-Ming Xu
- College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, P. R. China
| | - Jun He
- College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, P. R. China
| | - Min-Qiang Yu
- College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, P. R. China
| | - Guo-Xiang Shen
- College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, P. R. China
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561
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Hou X, Ren J, Wang S, He L. Establishment of a High Expression of α1A Adrenergic Receptor Cell Membrane Chromatography-RPLC Method for Screening Target Components from Radix Caulophylli. Chromatographia 2010. [DOI: 10.1365/s10337-010-1723-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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562
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Weitman M, Major DT. Challenges posed to bornyl diphosphate synthase: diverging reaction mechanisms in monoterpenes. J Am Chem Soc 2010; 132:6349-60. [PMID: 20394387 DOI: 10.1021/ja910134x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The simplest form of terpenoid chemistry is found for the monoterpenes, which give plants fragrance, flavor, and medicinal properties. Monoterpene synthases employ geranyl diphosphate as a substrate to generate an assortment of cyclic products. In the current study we present a detailed analysis of the multiple gas-phase reaction pathways in the synthesis of bornyl cation from geranyl diphosphate. Additionally, the fate of the proposed bornyl cation intermediate in the bornyl diphosphate synthase reaction is investigated by molecular dynamics simulations. We employ accurate density functional theory (DFT) methods after careful validation against high-level ab initio data for a set of model carbocations. The gas-phase results for the monoterpene reactions indicate a diverging reaction mechanism with multiple products in the absence of enzymatic control. This complex potential energy surface includes several possible bifurcation points due to the presence of secondary cations. Additionally, the suggested bornyl cation intermediate in the bornyl diphosphate synthase reaction is studied by molecular dynamics simulations employing a hybrid quantum mechanics (DFT)-molecular mechanics potential energy function. The simulations suggest that the bornyl cation is a transient species as in the gas phase and that electrostatic steering directs the formation of the final product, bornyl diphosphate.
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Affiliation(s)
- Michal Weitman
- Department of Chemistry and the Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel
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563
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Rajaganesh R, Jayakumar J, Sivaraj C, Raaman N, Das TM. Synthesis and antioxidant activity of a novel class of 4,6-O-protected O-glycosides and their utility in disaccharide synthesis. Carbohydr Res 2010; 345:1649-57. [DOI: 10.1016/j.carres.2010.04.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 02/09/2010] [Accepted: 04/22/2010] [Indexed: 10/19/2022]
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564
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A new A431/cell membrane chromatography and online high performance liquid chromatography/mass spectrometry method for screening epidermal growth factor receptor antagonists from Radix sophorae flavescentis. J Chromatogr A 2010; 1217:5246-52. [PMID: 20609442 DOI: 10.1016/j.chroma.2010.06.037] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 05/20/2010] [Accepted: 06/15/2010] [Indexed: 11/20/2022]
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565
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Guimarães DO, Borges WS, Vieira NJ, de Oliveira LF, da Silva CHTP, Lopes NP, Dias LG, Durán-Patrón R, Collado IG, Pupo MT. Diketopiperazines produced by endophytic fungi found in association with two Asteraceae species. PHYTOCHEMISTRY 2010; 71:1423-1429. [PMID: 20541231 DOI: 10.1016/j.phytochem.2010.05.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Revised: 05/07/2010] [Accepted: 05/11/2010] [Indexed: 05/29/2023]
Abstract
Diketopiperazine (DKP) derivatives, named colletopiperazine, fusaperazine C and E as well as four known DKPs were isolated from cultures of Colletotrichum gloeosporioides, Penicillium crustosum, both endophytic fungi isolated from Viguiera robusta, and a Fusarium spp., an endophyte of Viguiera arenaria, respectively. Their structures were established on the basis of their spectroscopic data. Conformational analysis of two known DKPs showed that folded conformations were as energetically stable as the extended one.
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Affiliation(s)
- Denise O Guimarães
- Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n, 14040-903 Ribeirão Preto, SP, Brazil
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566
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Abstract
Natural products have evolved to encompass a broad spectrum of chemical and functional diversity. It is this diversity, along with their structural complexity, that enables nature's small molecules to target a nearly limitless number of biological macromolecules and to often do so in a highly selective fashion. Because of these characteristics, natural products have seen great success as therapeutic agents. However, this vast pool of compounds holds much promise beyond the development of future drugs. These features also make them ideal tools for the study of biological systems. Recent examples of the use of natural products and their derivatives as chemical probes to explore biological phenomena and assemble biochemical pathways are presented here.
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Affiliation(s)
- Erin E. Carlson
- Departments of Chemistry and Molecular and Cellular Biochemistry, Indiana University, 212 S. Hawthorne Drive, Bloomington, Indiana 47405
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567
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Horai H, Arita M, Kanaya S, Nihei Y, Ikeda T, Suwa K, Ojima Y, Tanaka K, Tanaka S, Aoshima K, Oda Y, Kakazu Y, Kusano M, Tohge T, Matsuda F, Sawada Y, Hirai MY, Nakanishi H, Ikeda K, Akimoto N, Maoka T, Takahashi H, Ara T, Sakurai N, Suzuki H, Shibata D, Neumann S, Iida T, Tanaka K, Funatsu K, Matsuura F, Soga T, Taguchi R, Saito K, Nishioka T. MassBank: a public repository for sharing mass spectral data for life sciences. JOURNAL OF MASS SPECTROMETRY : JMS 2010; 45:703-14. [PMID: 20623627 DOI: 10.1002/jms.1777] [Citation(s) in RCA: 1438] [Impact Index Per Article: 102.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
MassBank is the first public repository of mass spectra of small chemical compounds for life sciences (<3000 Da). The database contains 605 electron-ionization mass spectrometry (EI-MS), 137 fast atom bombardment MS and 9276 electrospray ionization (ESI)-MS(n) data of 2337 authentic compounds of metabolites, 11 545 EI-MS and 834 other-MS data of 10,286 volatile natural and synthetic compounds, and 3045 ESI-MS(2) data of 679 synthetic drugs contributed by 16 research groups (January 2010). ESI-MS(2) data were analyzed under nonstandardized, independent experimental conditions. MassBank is a distributed database. Each research group provides data from its own MassBank data servers distributed on the Internet. MassBank users can access either all of the MassBank data or a subset of the data by specifying one or more experimental conditions. In a spectral search to retrieve mass spectra similar to a query mass spectrum, the similarity score is calculated by a weighted cosine correlation in which weighting exponents on peak intensity and the mass-to-charge ratio are optimized to the ESI-MS(2) data. MassBank also provides a merged spectrum for each compound prepared by merging the analyzed ESI-MS(2) data on an identical compound under different collision-induced dissociation conditions. Data merging has significantly improved the precision of the identification of a chemical compound by 21-23% at a similarity score of 0.6. Thus, MassBank is useful for the identification of chemical compounds and the publication of experimental data.
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Affiliation(s)
- Hisayuki Horai
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0035, Japan
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568
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569
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Riva R, Banfi L, Basso A, Cerulli V, Guanti G, Pani M. A Highly Convergent Synthesis of Tricyclic N-Heterocycles Coupling an Ugi Reaction with a Tandem SN2′-Heck Double Cyclization. J Org Chem 2010; 75:5134-43. [DOI: 10.1021/jo100859y] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Renata Riva
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
| | - Luca Banfi
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
| | - Andrea Basso
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
| | - Valentina Cerulli
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
| | - Giuseppe Guanti
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
| | - Marcella Pani
- Dipartimento di Chimica e Chimica Industriale, Via Docecaneso 31, 16146 Genova, Italy
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570
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De Simone F, Gertsch J, Waser J. Catalytic Selective Cyclizations of Aminocyclopropanes: Formal Synthesis of Aspidospermidine and Total Synthesis of Goniomitine. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201001853] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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571
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Harvey AL, Clark RL, Mackay SP, Johnston BF. Current strategies for drug discovery through natural products. Expert Opin Drug Discov 2010; 5:559-68. [PMID: 22823167 DOI: 10.1517/17460441.2010.488263] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE TO THE FIELD Natural products are the most consistently successful source of drug leads, both historically and currently. Despite this, the use of natural products in industrial drug discovery has fallen out of favour. Natural products are likely to continue to be sources of new commercially viable drug leads because the chemical novelty associated with natural products is higher than that of any other source: this is particularly important when searching for lead molecules against newly discovered targets for which there are no known small molecule leads. Areas to be covered: Current drug discovery strategies involving natural products are described in three sections: developments from traditionally used medicines, random testing of natural compounds on biological assays and use of virtual screening techniques with structures of natural products. WHAT THE READER WILL GAIN The reader will gain an insight into the potential for natural products in current drug discovery paradigms, particularly in the value of using natural products in virtual screening approaches. TAKE HOME MESSAGE Drug discovery would be enriched if fuller use was made of the chemistry of natural products.
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Affiliation(s)
- Alan L Harvey
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Sciences, 27 Taylor Street, Glasgow G4 0NR, UK +44 141 553 4155 ; +44 141 552 8376 ;
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572
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Xiao J, Wong ZZ, Lu YP, Loh TP. Hexahydropyrrolo[2,3-b]indoles: A New Class of Structurally Rigid Tricyclic Skeleton for Oxazaborolidine-Catalyzed Asymmetric Borane Reduction. Adv Synth Catal 2010. [DOI: 10.1002/adsc.200900908] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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573
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Zhou CY, Li J, Peddibhotla S, Romo D. Mild Arming and Derivatization of Natural Products via an In(OTf)3-Catalyzed Arene Iodination. Org Lett 2010; 12:2104-7. [DOI: 10.1021/ol100587j] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cong-Ying Zhou
- Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012
| | - Jing Li
- Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012
| | | | - Daniel Romo
- Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012
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574
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Erb J, Alden-Danforth E, Kopf N, Scerba MT, Lectka T. Combining asymmetric catalysis with natural product functionalization through enantioselective alpha-fluorination. J Org Chem 2010; 75:969-71. [PMID: 20039641 DOI: 10.1021/jo9024072] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An examination into the derivatization of various natural products using newly developed alpha-fluorination methodology is disclosed. An activated ketene enolate, generated from an acid chloride, is allowed to react with an electrophilic fluorine source (NFSi). Quenching the reaction with a nucleophilic natural product produces biologically relevant alpha-fluorinated carbonyl derivatives of select chemotherapeutics, antibiotics, and other pharmaceuticals.
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Affiliation(s)
- Jeremy Erb
- Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA
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575
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Hammill JT, Contreras-García J, Virshup AM, Beratan D, Yang W, Wipf P. Synthesis and chemical diversity analysis of bicyclo[3.3.1]non-3-en-2-ones. Tetrahedron 2010; 66:5852-5862. [PMID: 20798897 PMCID: PMC2925319 DOI: 10.1016/j.tet.2010.04.112] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Functionalized bicyclo[3.3.1]non-3-en-2-ones are obtained from commercially available phenols by a hypervalent iodine oxidation, enone epoxidation, epoxide thiolysis, and intramolecular aldol reaction sequence. Reaction optimization studies identified room temperature as well as microwave-mediated procedures, providing moderate to good yields (57%-88%) in the thiophenol-mediated epoxide opening and intramolecular aldol reaction. In addition, the isolation of a key intermediate and in situ NMR studies supported the mechanistic hypothesis. The bicyclic ring products occupy novel chemical space according to ChemGPS and Chemaxon chemical diversity and cheminformatics analyses.
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Affiliation(s)
- Jared T Hammill
- Center for Chemical Methodologies and Library Development, University of Pittsburgh, Pittsburgh, PA 15260, USA
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576
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Biochemical characterization of a novel indole prenyltransferase from Streptomyces sp. SN-593. J Bacteriol 2010; 192:2839-51. [PMID: 20348259 DOI: 10.1128/jb.01557-09] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genome sequencing of Streptomyces species has highlighted numerous potential genes of secondary metabolite biosynthesis. The mining of cryptic genes is important for exploring chemical diversity. Here we report the metabolite-guided genome mining and functional characterization of a cryptic gene by biochemical studies. Based on systematic purification of metabolites from Streptomyces sp. SN-593, we isolated a novel compound, 6-dimethylallylindole (DMAI)-3-carbaldehyde. Although many 6-DMAI compounds have been isolated from a variety of organisms, an enzyme catalyzing the transfer of a dimethylallyl group to the C-6 indole ring has not been reported so far. A homology search using known prenyltransferase sequences against the draft sequence of the Streptomyces sp. SN-593 genome revealed the iptA gene. The IptA protein showed 27% amino acid identity to cyanobacterial LtxC, which catalyzes the transfer of a geranyl group to (-)-indolactam V. A BLAST search against IptA revealed much-more-similar homologs at the amino acid level than LtxC, namely, SAML0654 (60%) from Streptomyces ambofaciens ATCC 23877 and SCO7467 (58%) from S. coelicolor A3(2). Phylogenetic analysis showed that IptA was distinct from bacterial aromatic prenyltransferases and fungal indole prenyltransferases. Detailed kinetic analyses of IptA showed the highest catalytic efficiency (6.13 min(-1) microM(-1)) for L-Trp in the presence of dimethylallyl pyrophosphate (DMAPP), suggesting that the enzyme is a 6-dimethylallyl-L-Trp synthase (6-DMATS). Substrate specificity analyses of IptA revealed promiscuity for indole derivatives, and its reaction products were identified as novel 6-DMAI compounds. Moreover, DeltaiptA mutants abolished the production of 6-DMAI-3-carbaldehyde as well as 6-dimethylallyl-L-Trp, suggesting that the iptA gene is involved in the production of 6-DMAI-3-carbaldehyde.
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577
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Robert FO, Pandhal J, Wright PC. Exploiting cyanobacterial P450 pathways. Curr Opin Microbiol 2010; 13:301-6. [PMID: 20299274 DOI: 10.1016/j.mib.2010.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 02/22/2010] [Accepted: 02/23/2010] [Indexed: 10/19/2022]
Abstract
Cytochrome P450s are hemoprotein oxygenases involved in natural product synthetic pathways. Cyanobacteria are oxygenic photosynthetic microorganisms and are considered a rich source of natural products, and are now known to harbour P450s. A variety of cyanobacterial species have been found to contain multiple copies of P450s in their genomes, and over 100 have been predicted. Interestingly, some are membrane-bound as in eukaryotes, as opposed to cytoplasmic in bacteria. Furthermore, they can complement plant P450s and perform bioremediation of oil spills by the breakdown of alkanes. Functional expression of a selection Nostoc spp. P450s in Escherichia coli, with associated enzymes, has successfully produced the sesquiterpenes--germacradienol, germacrene and B-elemene, although others have failed for undetermined reasons.
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Affiliation(s)
- Faith O Robert
- ChELSI Institute, Department of Chemical and Process Engineering, The University of Sheffield, Mappin Street, S1 3JD, Sheffield, UK
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578
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Vetter I, Davis JL, Rash LD, Anangi R, Mobli M, Alewood PF, Lewis RJ, King GF. Venomics: a new paradigm for natural products-based drug discovery. Amino Acids 2010; 40:15-28. [DOI: 10.1007/s00726-010-0516-4] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 02/04/2010] [Indexed: 10/19/2022]
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579
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Kanashiro A, Machado RR, Malvar DDC, Aguiar FA, Souza GEP. Quercetin does not alter lipopolysaccharide-induced fever in rats. J Pharm Pharmacol 2010; 60:357-62. [DOI: 10.1211/jpp.60.3.0011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Fever is considered an important component of the acute phase response of the body in defence against invading organisms such as bacteria. Quercetin, an important representative of the flavonoid class, has been extensively studied as an anti-inflammatory agent. In the present study, we investigated the effect of quercetin, administered orally (5, 25 and 50 mg kg−1) or intraperitoneally (50 mg kg−1), on the febrile response induced by either intraperitoneally (50 μg kg−1) or intravenously (5 μg kg−1) injected lipopolysaccharide (LPS from Escherichia coli) in rats. In contrast with the well known anti-inflammatory activity of quercetin, the results demonstrate that quercetin, at the doses used, did not alter the fever induced by LPS, regardless of the route of administration.
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Affiliation(s)
- Alexandre Kanashiro
- Departamento de Física e Química, Faculdade de Ciẽncias Farmacẽuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Renes R Machado
- Departamento de Física e Química, Faculdade de Ciẽncias Farmacẽuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - David do C Malvar
- Departamento de Física e Química, Faculdade de Ciẽncias Farmacẽuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernando A Aguiar
- Departamento de Física e Química, Faculdade de Ciẽncias Farmacẽuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Glória E P Souza
- Departamento de Física e Química, Faculdade de Ciẽncias Farmacẽuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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580
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Abstract
Methylene C-H bonds are among the most difficult chemical bonds to selectively functionalize because of their abundance in organic structures and inertness to most chemical reagents. Their selective oxidations in biosynthetic pathways underscore the power of such reactions for streamlining the synthesis of molecules with complex oxygenation patterns. We report that an iron catalyst can achieve methylene C-H bond oxidations in diverse natural-product settings with predictable and high chemo-, site-, and even diastereoselectivities. Electronic, steric, and stereoelectronic factors, which individually promote selectivity with this catalyst, are demonstrated to be powerful control elements when operating in combination in complex molecules. This small-molecule catalyst displays site selectivities complementary to those attained through enzymatic catalysis.
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Affiliation(s)
- Mark S Chen
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL 61801, USA
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581
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Neier R, Kholod I, Vallat O, Buciumas AM. Synthesis of Rhazinilam: A Comparative Review of Forty Years of Synthetic Endeavors. HETEROCYCLES 2010. [DOI: 10.3987/rev-10-sr(e)2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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582
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Nicolai S, Erard S, González DF, Waser J. Pd-Catalyzed Intramolecular Oxyalkynylation of Alkenes with Hypervalent Iodine. Org Lett 2009; 12:384-7. [DOI: 10.1021/ol9027286] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stefano Nicolai
- Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland
| | - Stéphane Erard
- Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland
| | - Davinia Fernández González
- Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland
| | - Jérôme Waser
- Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015 Lausanne, Switzerland
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583
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Wu J, Zhang HB, Xu JL, Cox RJ, Simpson TJ, Zhang LH. 13C labeling reveals multiple amination reactions in the biosynthesis of a novel polyketide polyamine antibiotic zeamine from Dickeya zeae. Chem Commun (Camb) 2009; 46:333-5. [PMID: 20024369 DOI: 10.1039/b916307g] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structure of zeamine, a novel polyamino-amide antibiotic metabolite of Dickeya zeae has been established by NMR and detailed MS analyses; labelling studies with (13)C-labelled acetates suggest that the repeating secondary amine containing motif may be biosynthesised via a modular PKS containing aminotransferase domains.
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Affiliation(s)
- Jien Wu
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673.
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584
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Maréchal JP, Hellio C. Challenges for the development of new non-toxic antifouling solutions. Int J Mol Sci 2009; 10:4623-4637. [PMID: 20087457 PMCID: PMC2808003 DOI: 10.3390/ijms10114623] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 10/26/2009] [Indexed: 11/30/2022] Open
Abstract
Marine biofouling is of major economic concern to all marine industries. The shipping trade is particularly alert to the development of new antifouling (AF) strategies, especially green AF paint as international regulations regarding the environmental impact of the compounds actually incorporated into the formulations are becoming more and more strict. It is also recognised that vessels play an extensive role in invasive species propagation as ballast waters transport potentially threatening larvae. It is then crucial to develop new AF solutions combining advances in marine chemistry and topography, in addition to a knowledge of marine biofoulers, with respect to the marine environment. This review presents the recent research progress made in the field of new non-toxic AF solutions (new microtexturing of surfaces, foul-release coatings, and with a special emphasis on marine natural antifoulants) as well as the perspectives for future research directions.
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Affiliation(s)
- Jean-Philippe Maréchal
- Observatoire du Milieu Marin Martiniquais, 3 avenue Condorcet, 97 200 Fort de France, Martinique, FWI, France; E-Mail:
| | - Claire Hellio
- School of Biological Sciences, King Henry Building, Portsmouth University, Portsmouth PO1 2DY, UK
- Author to whom correspondence should be addressed; E-Mail:
; Tel.: + 44-239-284-2073; Fax: +44-239-284-2070
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585
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Affiliation(s)
- Jon Clardy
- Department of Biological Chemistry and Molecular Pharmacology, Harvard University, Boston, MA 02115, USA.
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586
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Kumar BRP, Soni M, Bhikhalal UB, Kakkot IR, Jagadeesh M, Bommu P, Nanjan MJ. Analysis of physicochemical properties for drugs from nature. Med Chem Res 2009. [DOI: 10.1007/s00044-009-9244-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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587
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Hou X, Zhou M, Jiang Q, Wang S, He L. A vascular smooth muscle/cell membrane chromatography–offline-gas chromatography/mass spectrometry method for recognition, separation and identification of active components from traditional Chinese medicines. J Chromatogr A 2009; 1216:7081-7. [DOI: 10.1016/j.chroma.2009.08.062] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 08/15/2009] [Accepted: 08/25/2009] [Indexed: 11/15/2022]
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588
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Cragg GM, Grothaus PG, Newman DJ. Impact of natural products on developing new anti-cancer agents. Chem Rev 2009; 109:3012-43. [PMID: 19422222 DOI: 10.1021/cr900019j] [Citation(s) in RCA: 887] [Impact Index Per Article: 59.1] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Gordon M Cragg
- Natural Products Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, NCI-Frederick, Fairview Center, Suite 206, P.O. Box B, Frederick, Maryland 21702-1201, USA
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589
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Increasing diterpene yield with a modular metabolic engineering system in E. coli: comparison of MEV and MEP isoprenoid precursor pathway engineering. Appl Microbiol Biotechnol 2009; 85:1893-906. [PMID: 19777230 PMCID: PMC2811251 DOI: 10.1007/s00253-009-2219-x] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Accepted: 08/22/2009] [Indexed: 12/05/2022]
Abstract
Engineering biosynthetic pathways in heterologous microbial host organisms offers an elegant approach to pathway elucidation via the incorporation of putative biosynthetic enzymes and characterization of resulting novel metabolites. Our previous work in Escherichia coli demonstrated the feasibility of a facile modular approach to engineering the production of labdane-related diterpene (20 carbon) natural products. However, yield was limited (<0.1 mg/L), presumably due to reliance on endogenous production of the isoprenoid precursors dimethylallyl diphosphate and isopentenyl diphosphate. Here, we report incorporation of either a heterologous mevalonate pathway (MEV) or enhancement of the endogenous methyl erythritol phosphate pathway (MEP) with our modular metabolic engineering system. With MEP pathway enhancement, it was found that pyruvate supplementation of rich media and simultaneous overexpression of three genes (idi, dxs, and dxr) resulted in the greatest increase in diterpene yield, indicating distributed metabolic control within this pathway. Incorporation of a heterologous MEV pathway in bioreactor grown cultures resulted in significantly higher yields than MEP pathway enhancement. We have established suitable growth conditions for diterpene production levels ranging from 10 to >100 mg/L of E. coli culture. These amounts are sufficient for nuclear magnetic resonance analyses, enabling characterization of enzymatic products and hence, pathway elucidation. Furthermore, these results represent an up to >1,000-fold improvement in diterpene production from our facile, modular platform, with MEP pathway enhancement offering a cost effective alternative with reasonable yield. Finally, we reiterate here that this modular approach is expandable and should be easily adaptable to the production of any terpenoid natural product.
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590
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Antibacterial activity of 2-(2',4'-dibromophenoxy)-4,6-dibromophenol from Dysidea granulosa. Mar Drugs 2009; 7:464-71. [PMID: 19841726 PMCID: PMC2763112 DOI: 10.3390/md7030464] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 09/01/2009] [Accepted: 09/21/2009] [Indexed: 11/16/2022] Open
Abstract
2-(2′,4′-Dibromophenoxy)-4,6-dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity, especially against methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), vancomycin resistant Enterococci (VRE), vancomycin sensitive Enterococci (VSE) and Bacillus spp. Minimal inhibitory concentration (MIC) was evaluated against 57 clinical and standard strains of Gram positive and Gram negative bacteria. The observed MIC range was 0.117–2.5 μg/mL against all the Gram positive bacteria and 0.5–2 μg/mL against Gram negative bacteria. The in-vitro antibacterial activity observed was better than that of the standard antibiotic linezolid, a marketed anti-MRSA drug. The results establish 2-(2′,4′-dibromophenoxy)-4,6-dibromophenol, as a potential lead molecule for anti-MRSA and anti-VRE drug development.
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591
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Preventive and curative glycoside kaempferol treatments attenuate the TH2-driven allergic airway disease. Int Immunopharmacol 2009; 9:1540-8. [PMID: 19755174 DOI: 10.1016/j.intimp.2009.09.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 08/19/2009] [Accepted: 09/06/2009] [Indexed: 02/05/2023]
Abstract
Asthma is a chronic respiratory disease characterized by airway inflammation and airway hyperresponsiveness (AHR). One strategy to treat allergic diseases is the development of new drugs. Flavonoids are compounds derived from plants and are known to have antiallergic, anti-inflammatory, and antioxidant properties. To investigate whether the flavonoid kaempferol glycoside 3-O-[beta-d-glycopiranosil-(1-->6)-alpha-l-ramnopiranosil]-7-O-alpha-l-ramnopiranosil-kaempferol (GRRK) would be capable of modulating allergic airway disease (AAD) either as a preventive (GRRK P) or curative (GRRK C) treatment in an experimental model of asthma. At weekly intervals, BALB/c mice were subcutaneously (sc) sensitized twice with ovalbumin (OVA)/alum and challenged twice with OVA administered intranasally. To evaluate any preventive effect, GRRK was administered 1h (hour) before each OVA-sensitization and challenge, while to analyze the curative effect, mice were first sensitized with OVA, followed by GRRK given at day 18 through 21. The onset of AAD was evaluated 24h after the last OVA challenge. Both treatments resulted in a dose-dependent reduction in total leukocyte and eosinophil counts in the bronchoalveolar lavage fluid (BAL). GRRK also decreased CD4(+), B220(+), MHC class II and CD40 molecule expressions in BAL cells. Histology and lung mechanic showed that GRRK suppressed mucus production and ameliorated the AHR induced by OVA challenge. Furthermore, GRRK impaired Th2 cytokine production (IL-5 and IL-13) and did not induce a Th1 pattern of inflammation. These findings demonstrate that GRRK treatment before or after established allergic lung disease down-regulates key asthmatic features. Therefore, GRRK has a potential clinical use for the treatment of allergic asthma.
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592
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Jyothi D, Vanathi P, Mangala Gowri P, Rama Subba Rao V, Madhusudana Rao J, Sreedhar AS. Diferuloylmethane augments the cytotoxic effects of piplartine isolated from Piper chaba. Toxicol In Vitro 2009; 23:1085-91. [PMID: 19501152 DOI: 10.1016/j.tiv.2009.05.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 05/26/2009] [Accepted: 05/29/2009] [Indexed: 01/01/2023]
Abstract
Natural compound based anticancer drug discovery is gaining interest against a wide variety of tumors. E-piplartine (trans-piplartine), a natural compound isolated from Piper chaba roots is examined against rat histiocytoma (BC-8), mouse embryonal carcinoma (PCC4), mouse macrophages (P388D1 and J774), and human neuroblastoma (IMR32) tumor cells. While Z-piplartine (cis-piplartine) failed to induce cytotoxicity (even at higher concentrations, 50 microM), E-piplartine induced a dose-dependent cytotoxicity (2-24 microM) in different tumor cells. The combinatorial treatment of piplartine with diferuloylmethane (curcumin), an anti-inflammatory and anticancer agent, significantly enhanced the piplartine induced cytotoxicity in tumor cells. Diferuloylmethane itself is not cytotoxic at 15 microM concentration; however, potentiated the piplartine induced cytotoxicity. The tumor cell killing with piplartine is preceded by G1 cell cycle arrest, and surpassed diferuloylmethane induced G2/M arrest when used in combination. In PCC4 cells, piplartine inhibited the cell cycle progression by inactivating cdk2 and destabilizing cyclin D1, whereas diferuloylmethane combination inhibited the ERK1/2 and Raf-1 signaling in addition to the inhibition of cell cycle progression. The over expression of heat shock protein 70, Hsp70 in rat histiocytic tumor cells interfered with piplartine induced cytotoxicity, hence, a cross talk between stress response and anticancer agents is presented. Our data demonstrates the biological and medicinal importance of piplartine isolated from the roots of P. chaba, and indicates that E-piplartine may be a promising candidate to use in combinatorial treatments to combat cancer.
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Affiliation(s)
- D Jyothi
- Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
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593
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Triggle DJ. The chemist as astronaut: Searching for biologically useful space in the chemical universe. Biochem Pharmacol 2009; 78:217-23. [DOI: 10.1016/j.bcp.2009.02.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 02/19/2009] [Accepted: 02/19/2009] [Indexed: 12/21/2022]
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594
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Salazar MO, Ramallo IA, Micheloni O, Sierra MG, Furlan RLE. Chemically engineered extracts: bioactivity alteration through sulfonylation. Bioorg Med Chem Lett 2009; 19:5067-70. [PMID: 19635668 DOI: 10.1016/j.bmcl.2009.07.038] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 07/03/2009] [Accepted: 07/07/2009] [Indexed: 12/16/2022]
Abstract
The chemical composition and the biomolecular properties of a series of crude plant extracts were altered without previous knowledge of their detailed chemical composition.
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Affiliation(s)
- Mario O Salazar
- Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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595
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Prabhakar KR, Veerapur VP, Parihar KV, Priyadarsini KI, Rao BSS, Unnikrishnan MK. Evaluation and optimization of radioprotective activity ofCoronopus didymusLinn. in γ-irradiated mice. Int J Radiat Biol 2009; 82:525-36. [PMID: 16966180 DOI: 10.1080/09553000600876686] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate and optimize the radioprotective ability of the most potent fraction of an aqueous extract of Coronopus didymus in whole body gamma-irradiated Swiss albino mice and to evaluate the antioxidant status and lipid peroxidation of the livers of the surviving mice. To correlate the free radical scavenging studies with in vivo radioprotection ability. MATERIALS AND METHODS Swiss albino mice were treated with either vehicle or the different doses of extract/fraction suspension by an i.p. route, 30 min before exposure to 10 Gy gamma-irradiation and the animals were monitored twice daily for any signs of radiation toxicity and mortality. Radiation dose response (7-11 Gy), optimization of route, time of drug administration and evaluation of dose response factor (DRF) at the best dose of the fraction was studied. Endogenous antioxidant status and lipid peroxidation of the livers of the mice surviving on the 31st day was evaluated by using spectrophotometric methods. RESULTS The most active free radical scavenging fraction (CDF1) as assessed by competition kinetic studies using pulse radiolysis showed maximum in vivo radioprotection of 70% at a dose of 400 mg/kg body weight (bw) compared to corresponding 10 Gy irradiated control. Optimum radioprotection was observed upon i.p. administration, 30 min prior to 10 Gy irradiation and DRF at a dose of 400 mg/kg bw for 30 day survival was found to be 1.07. The levels of endogenous antioxidant enzymes and lipid peroxidation in the CDF1 treated surviving mice were found to reverse back to their normal levels. CONCLUSIONS The optimum dose, time and route of drug administration for maximum radioprotection by CDF1 were determined. The reversal of the levels of endogenous antioxidant enzymes and lipid peroxidation indicates reduced oxidative stress in CDF1 treated surviving mice.
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Affiliation(s)
- K R Prabhakar
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal, India
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596
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Forbey JS, Harvey AL, Huffman MA, Provenza FD, Sullivan R, Tasdemir D. Exploitation of secondary metabolites by animals: A response to homeostatic challenges. Integr Comp Biol 2009; 49:314-28. [PMID: 21665822 DOI: 10.1093/icb/icp046] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We propose that the exploitation of the bioactive properties of secondary metabolites (SMs) by animals can provide a "treatment" against various challenges that perturb homeostasis in animals. The unified theoretical framework for the exploitation of SMs by animals is based on a synthesis of research from a wide range of fields and although it is focused on providing generalized predictions for herbivores that exploit SMs of plants, predictions can be applied to understand the exploitation of SMs by many animals. In this review, we argue that the probability of SM exploitation is determined by the relative difference between the cost of a homeostatic challenge and the toxicity of the SM and we provide various predictions that can be made when considering behavior under a homeostatic perspective. The notion that animals experience and respond to costly challenges by exploiting therapeutic SMs provides a relatively novel perspective to explain foraging behavior in herbivores, specifically, and behavior of animals in general. We provide evidence that animals can exploit the biological activity of SMs to mitigate the costs of infection by parasites, enhance reproduction, moderate thermoregulation, avoid predation, and increase alertness. We stress that a better understanding of animal behavior requires that ecologists look beyond their biases that SMs elicit punishment and consider a broader view of avoidance or selection of SMs relative to the homeostatic state. Finally, we explain how understanding exploitation of SMs by animals could be applied to advance practices of animal management and lead to discovery of new drugs.
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Affiliation(s)
- Jennifer S Forbey
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA.
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597
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Yan J, Gupta S, Sherman DH, Reynolds KA. Functional dissection of a multimodular polypeptide of the pikromycin polyketide synthase into monomodules by using a matched pair of heterologous docking domains. Chembiochem 2009; 10:1537-43. [PMID: 19437523 PMCID: PMC4652847 DOI: 10.1002/cbic.200900098] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Indexed: 11/08/2022]
Abstract
The pikromyin polyketide synthase (PKS) in Streptomyces venezulae is comprised of a loading module and six extension modules, which generate the corresponding 14-membered macrolactone product. PikAI is a multimodular component of this PKS and houses both the loading domain and the first two extension modules, joined by short intraprotein linkers. We have shown that PikAI can be separated into two proteins at either of these linkers, only when matched pairs of docking domains (DDs) from a heterologous modular phoslactomycin PKS are used in place of the intraprotein linker. In both cases the yields of pikromycin produced by the S. venezuelae mutant were 50% of that of a S. venezuelae strain expressing the native trimodular PikAI. This observation provides the first demonstration that such separations do not dramatically impact the efficiency of the entire in vivo biosynthetic process. Expression of module 2 as a monomodular protein fused to a heterologous N-terminal docking domain was also observed to give almost a tenfold improvement in the in vivo generation of pikromycin from a synthetic diketide intermediate. These results demonstrate the utility of DDs to manipulate biosynthetic processes catalyzed by modular PKSs and the quest to generate novel polyketide products.
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Affiliation(s)
- John Yan
- Department of Chemistry, Portland State University, 262 Science Building 2, 1719 SW 10th Avenue, Portland, OR 97201, FAX: 503- 725 9525
| | - Shuchi Gupta
- Department of Chemistry, Portland State University, 262 Science Building 2, 1719 SW 10th Avenue, Portland, OR 97201, FAX: 503- 725 9525
| | - David H. Sherman
- Life Sciences Institute and Department of Medicinal Chemistry, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, Fax: 734-615-3641
| | - Kevin A. Reynolds
- Department of Chemistry, Portland State University, 262 Science Building 2, 1719 SW 10th Avenue, Portland, OR 97201, FAX: 503- 725 9525
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598
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Yang P, Litwinski GR, Pursch M, McCabe T, Kuppannan K. Separation of natural product using columns packed with Fused-Core particles. J Sep Sci 2009; 32:1816-22. [DOI: 10.1002/jssc.200900005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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599
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Kinghorn AD, Carcache de Blanco EJ, Chai HB, Orjala J, Farnsworth NR, Soejarto DD, Oberlies NH, Wani MC, Kroll DJ, Pearce CJ, Swanson SM, Kramer RA, Rose WC, Fairchild CR, Vite GD, Emanuel S, Jarjoura D, Cope FO. Discovery of anticancer agents of diverse natural origin. ACTA ACUST UNITED AC 2009; 81:1051-1063. [PMID: 20046887 DOI: 10.1351/pac-con-08-10-16] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A collaborative multidisciplinary research project is described in which new natural product anticancer drug leads are obtained from a diverse group of organisms, constituted by tropical plants, aquatic cyanobacteria, and filamentous fungi. Information is provided on how these organisms are collected and processed. The types of bioassays are indicated in which crude extracts of these acquisitions are tested. Progress made in the isolation of lead bioactive secondary metabolites from three tropical plants is discussed.
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600
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Miller SJ. Chemistry. Total chemical synthesis peers into the biosynthetic black box. Science 2009; 324:186-7. [PMID: 19359569 DOI: 10.1126/science.1172081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Scott J Miller
- Department of Chemistry, Yale University, New Haven, CT 06520, USA.
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