European Journal of Organic Chemistry

Cover image for Vol. 2012 Issue 27

September 2012

Volume 2012, Issue 27

Pages 5099–5405

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. You have free access to this content
      Epicolactone – Natural Product Isolated from the Sugarcane Endophytic Fungus Epicoccum nigrum (Eur. J. Org. Chem. 27/2012)

      Francisca Diana da Silva Araújo, Léia Cecilia de Lima Fávaro, Welington Luiz Araújo, Fábio Lazzarotto de Oliveira, Ricardo Aparicio and Anita Jocelyne Marsaioli

      Version of Record online: 10 SEP 2012 | DOI: 10.1002/ejoc.201290072

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      The cover picture shows on the left-hand side, sugarcane growing in S. Paulo, Brazil, from which the endophytic fungus Epicoccum nigrum was isolated. A picture of this fungus growing on an agar plate is also shown. The X-ray crystallographic structure of epicolactone, a novel E. nigrum pentacyclic metabolite isolated from an ethyl acetate extract, is depicted on the right-hand side. Evidence suggests that epicolactone is produced through a polyketide synthase (PKS) biosynthetic pathway. Details are discussed in the article by A. J. Marsaioli et al. on p. 5225 ff. We thank Yara Gomes Pereira Aparicio for the cover picture design.

  2. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
  3. News

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
  4. Microreview

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Diterpene Drugs

      Diterpenes from European Euphorbia Species Serving as Prototypes for Natural-Product-Based Drug Discovery (pages 5115–5130)

      Andrea Vasas, Dóra Rédei, Dezső Csupor, Joseph Molnár and Judit Hohmann

      Version of Record online: 20 AUG 2012 | DOI: 10.1002/ejoc.201200733

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      This review covers recent discoveries involving the isolation, structure determination and pharmacological investigation of diterpenes from Euphorbia species, including the main aspects of the development of ingenol 3-angelate as a drug.

      Corrected by:

      Correction: Diterpenes from European Euphorbia Species Serving as Prototypes for Natural-Product-Based Drug Discovery

      Vol. 2012, Issue 35, 6996, Version of Record online: 7 NOV 2012

  5. Short Communications

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Marine Natural Products

      Antifungal Diterpene Alkaloids from the Caribbean Sponge Agelas citrina: Unified Configurational Assignments of Agelasidines and Agelasines (pages 5131–5135)

      E. Paige Stout, Lily C. Yu and Tadeusz F. Molinski

      Version of Record online: 25 JUN 2012 | DOI: 10.1002/ejoc.201200572

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      Chiroptical methods, including molar rotations and application of van't Hoff's principle of optical superposition, were applied to solve the configurations of two new diterpenoid alkaloids isolated from Agelas citrina, a sponge endemic to the Bahamas.

    2. Photochromism

      The Δ2,2′-Bi(2H-1,4-benzothiazine) Structural Motif of Red Hair Pigments Revisited: Photochromism and Acidichromism in a Unique Four-State System (pages 5136–5140)

      Loredana Leone, Orlando Crescenzi, Alessandra Napolitano, Vincenzo Barone and Marco d'Ischia

      Version of Record online: 25 JUL 2012 | DOI: 10.1002/ejoc.201200673

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      The stable yellow form of Δ2,2′-bi(2H-1,4-benzothiazine) (BBTZ) is shown to be the Z rather than E isomer, as originally suggested. The latter configuration pertains to the red photoexcited form. A blue species produced by diprotonation of BBTZ in 2 M HCl is also disclosed. BBTZ is thus proposed as a robust bioinspired four-state chromic system.

  6. Full Papers

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Cytotoxic Lipopeptides

      Lyngbyabellins K–N from Two Palmyra Atoll Collections of the Marine Cyanobacterium Moorea bouillonii (pages 5141–5150)

      Hyukjae Choi, Emily Mevers, Tara Byrum, Frederick A. Valeriote and William H. Gerwick

      Version of Record online: 14 AUG 2012 | DOI: 10.1002/ejoc.201200691

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      Two independent collections of the marine cyanobacterium Moorea bouillonii led to the isolation of five lipopeptides of the lyngbyabellin structure class. Their structures were elucidated by various spectroscopy, synthesis, and chromatography techniques. Lyngbyabellin N showed strong cytotoxic activity against the HCT116 colon cancer cell line (IC50 = 40.9 ± 3.3 nM).

    2. Total Synthesis

      Evolution of a Synthetic Strategy for the Variecolortides (pages 5151–5161)

      Christian A. Kuttruff, Peter Mayer and Dirk Trauner

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200712

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      Variations on a theme by Aspergillus variecolor: The concise total syntheses of the variecolortides, in particular of variecolortide C, are presented.

    3. Natural Products

      Sesquiterpenoids from Common Ragweed (Ambrosia artemisiifolia L.), an Invasive Biological Polluter (pages 5162–5170)

      Orazio Taglialatela-Scafati, Federica Pollastro, Alberto Minassi, Giuseppina Chianese, Luciano De Petrocellis, Vincenzo Di Marzo and Giovanni Appendino

      Version of Record online: 3 AUG 2012 | DOI: 10.1002/ejoc.201200650

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      Eight novel sesquiterpenoids were isolated from the aerial parts of Ambrosia artemisiifolia, an invasive weed whose pollen is responsible for severe allergic reactions. α,β-Unsaturated carbonyl derivatives were present in all aerial parts of the plant, and their reaction with thiols was correlated with the activation of TRPA1, a polymodal sensor involved in airways sensory irritation.

    4. Blurring the Boundary between Bio- and Geohopanoids: Plakohopanoid, a C32 Biohopanoid Ester from Plakortis cf. lita (pages 5171–5176)

      Valeria Costantino, Gerardo Della Sala, Alfonso Mangoni, Cristina Perinu and Roberta Teta

      Version of Record online: 14 AUG 2012 | DOI: 10.1002/ejoc.201200676

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      Plakohopanoid is a new type of hopanoid composed of a C32 hopanoic acid ester linked to a mannosyl-myo-inositol. It is probably produced by bacterial symbionts of Plakortis cf. lita. The existence of a biosynthetic pathway to the C32 hopanoic acid shows that this compound should not be necessarily considered to be a geohopanoid.

    5. Structures and Antibacterial Activities of Minor Dolabellanes from the Brown Alga Dilophus spiralis (pages 5177–5186)

      Efstathia Ioannou, Antonio Quesada, M. Mukhlesur Rahman, Simon Gibbons, Constantinos Vagias and Vassilios Roussis

      Version of Record online: 2 AUG 2012 | DOI: 10.1002/ejoc.201200533

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      Thirteen new minor dolabellane diterpenes (113) were isolated from the brown alga Dilophus spiralis. Their structures were established through analyses of their spectroscopic data. Compounds 1 and 4 exhibited comparable to 64-fold stronger activities than the standard antibiotic norfloxacin against one methicillin-resistant and two multidrug-resistant effluxing Staphylococcus aureus strains.

    6. Total Synthesis

      The First Total Synthesis of Solomonsterol B, a Marine Pregnane X Receptor Agonist (pages 5187–5194)

      Valentina Sepe, Raffaella Ummarino, Maria Valeria D'Auria, Barbara Renga, Stefano Fiorucci and Angela Zampella

      Version of Record online: 19 JUL 2012 | DOI: 10.1002/ejoc.201200619

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      We report the first total synthesis of solomonsterol B, a marine steroid endowed with potent agonistic activity towards the pregnane X receptor (PXR). This synthesis was completed in a total of 13 steps starting from hyodeoxycholic acid, with an overall yield of 10 %. The preparation of a side-chain-modified derivative and a preliminary structure–activity relationship on PXR is also reported.

    7. Natural Product Synthesis

      Synthesis of SHIP1-Activating Analogs of the Sponge Meroterpenoid Pelorol (pages 5195–5207)

      Labros G. Meimetis, Matt Nodwell, Lu Yang, Xiaoxia Wang, Joyce Wu, Curtis Harwig, Grant R. Stenton, Lloyd F. Mackenzie, Thomas MacRury, Brian O. Patrick, Andrew Ming-Lum, Christopher J. Ong, Gerald Krystal, Alice L. -F. Mui and Raymond J. Andersen

      Version of Record online: 3 AUG 2012 | DOI: 10.1002/ejoc.201200631

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      Two biomimetic routes have been used to synthesize analogs of the SHIP1-activating sponge meroterpenoid pelorol (1) in high ee. Resorcinol analog 18 is the most effective SHIP1-activating pelorol analog made to date and racemic 28·HCl, an amino analog, activates SHIP1 in vitro, and has effective antiinflammatory activity in a mouse model (ED50 ≈ 0.1 mg/kg).

    8. Natural Products

      Diterpenoids from Marine Ciliates: Chemical Polymorphism of Euplotes rariseta (pages 5208–5216)

      Graziano Guella, Emanuela Callone, Ines Mancini, Fernando Dini and Graziano Di Giuseppe

      Version of Record online: 2 AUG 2012 | DOI: 10.1002/ejoc.201200559

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      A thorough investigation carried out on several strains of marine ciliate species Euplotes rariseta allowed us to isolate regular and irregular diterpenoids, the structures of which are based on the rarisetane skeleton. A plausible comprehensive metabolic pathway is reported and phylogenetic relationships are discussed.

    9. Medicinal Chemistry

      Resveratrol-Related Dehydrodimers: Laccase-Mediated Biomimetic Synthesis and Antiproliferative Activity (pages 5217–5224)

      Vedamurthy M. Bhusainahalli, Carmela Spatafora, Malik Chalal, Dominique Vervandier-Fasseur, Philippe Meunier, Norbert Latruffe and Corrado Tringali

      Version of Record online: 26 JUL 2012 | DOI: 10.1002/ejoc.201200664

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      Seven resveratrol-related dehydrodimers were obtained by biomimetic oxidative coupling in the presence of laccase from Trametes versicolor. Some of these products were found to be active in an antiproliferative bioassay against SW480 human colon cancer cells.

    10. Natural Products Chemistry

      Epicolactone – Natural Product Isolated from the Sugarcane Endophytic Fungus Epicoccum nigrum (pages 5225–5230)

      Francisca Diana da Silva Araújo, Léia Cecilia de Lima Fávaro, Welington Luiz Araújo, Fábio Lazzarotto de Oliveira, Ricardo Aparicio and Anita Jocelyne Marsaioli

      Version of Record online: 15 AUG 2012 | DOI: 10.1002/ejoc.201200757

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      Chemical studies of an ethyl acetate extract of E. nigrum led to the isolation of mellein, 4,5-dimethylresorcinol, and the new natural product epicolactone. E. nigrum strains modified by Agrobacterium tumefaciens produced 4-hydroxymellein, indicating that genes responsible for regulation of monooxygenase were activated in the mutants.

    11. Donor–Acceptor Dyes

      Arylamine-Modified Thiazoles as Donor–Acceptor Dyes: Quantum Chemical Evaluation of the Charge-Transfer Process and Testing as Ligands in Ruthenium(II) Complexes (pages 5231–5247)

      Roberto Menzel, Stephan Kupfer, Ralf Mede, Dieter Weiß, Helmar Görls, Leticia González and Rainer Beckert

      Version of Record online: 9 AUG 2012 | DOI: 10.1002/ejoc.201200688

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      Several 4-hydroxy-1,3-thiazole-based chromophores bearing different arylamine donor and N-heterocyclic acceptor moieties were synthesized and their electronic properties were investigated experimentally and theoretically (DFT and TDDFT). The nature of the charge-transfer transition was identified. Additionally, the dyes were applied as light-harvesting ligands in heteroleptic RuII complexes.

    12. Dye-Sensitized Solar Cells

      Efficient Metal-Free Organic Sensitizers Containing Tetraphenylethylene Moieties in the Donor Part for Dye-Sensitized Solar Cells (pages 5248–5255)

      Jie Shi, Jing Huang, Runli Tang, Zhaofei Chai, Jianli Hua, Jingui Qin, Qianqian Li and Zhen Li

      Version of Record online: 2 AUG 2012 | DOI: 10.1002/ejoc.201200530

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      Two novel propeller-shaped D-π-A organic sensitizers that contain two tetraphenylethylene (TPE) moieties in the donor part of the triphenylamine group are designed and utilized in dye-sensitized solar cells.

    13. Indolo-sesquiterpenes

      N–N-Coupled Indolo-sesquiterpene Atropo-Diastereomers from a Marine-Derived Actinomycete (pages 5256–5262)

      Qingbo Zhang, Attila Mándi, Sumei Li, Yuchan Chen, Wenjun Zhang, Xinpeng Tian, Haibo Zhang, Huixian Li, Weimin Zhang, Si Zhang, Jianhua Ju, Tibor Kurtán and Changsheng Zhang

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200599

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      Dixiamycins A (1) and B (2), two atropo-diastereomers with an unusual N–N-coupled dimeric indolo-sesquiterpene skeleton and a stereogenic N–N axis, were characterized from a marine-derived Actinomycete and showed better bioactivities than the corresponding monomers. In addition, two new indolo-sesquiterpenes, oxiamycin (3) and chloroxiamycin (4), and the known compound xiamycin A (5) are reported.

    14. Bifunctional Materials

      Synthesis, Properties and Applications of Biphenyl Functionalized 9,9-Bis(4-diphenylaminophenyl)fluorenes as Bifunctional Materials for Organic Electroluminescent Devices (pages 5263–5274)

      A-monrat Thangthong, Narid Prachumrak, Supawadee Namuangruk, Siriporn Jungsuttiwong, Tinnagon Keawin, Taweesak Sudyoadsuk and Vinich Promarak

      Version of Record online: 2 AUG 2012 | DOI: 10.1002/ejoc.201200641

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      Newly designed biphenyl functionalized9,9-bis(4-diphenylaminophenyl)fluorenesshow promising potential as deep-blue emitters and hole-transporters for OLEDs. Efficient nondoped deep-blue and Alq3-based green OLEDs with maximum luminance efficiencies of 2.48 and 4.40 cd/A are achieved, respectively

    15. Lectin–Ligand Interactions

      Structural Study of Binding of α-Mannosides to Mannan-Binding Lectins (pages 5275–5281)

      Roberta Marchetti, Rosa Lanzetta, Ian C. Michelow, Antonio Molinaro and Alba Silipo

      Version of Record online: 16 AUG 2012 | DOI: 10.1002/ejoc.201200697

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      We have used an NMR-based approach to study, at atomic level, the mannose-binding activities both of recombinant human MBL (rhMBL) and of the chimeric molecule L-FCN/MBL76, in order to find new therapeutic strategies against N-glycosylated viruses.

    16. Dioxopyrrolopyrrole Derivatives

      Synthesis and Characterization of Dioxopyrrolopyrrole Derivatives Having Electron-Withdrawing Groups (pages 5282–5290)

      Takuya Yamagata, Junpei Kuwabara and Takaki Kanbara

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200761

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      The redox properties of the DPP (dioxopyrrolopyrrole) core were modulated by the introduction of electron-withdrawing groups, which resulted in the enhancement of the electron-accepting ability of the DPP core. In particular, DPP derivatives with 1,1,4,4-tetracyanobutadiene (TCBD) moieties exhibited a unique electrochemical response such as undergoing a reversible five-electron reduction.

    17. Peptides Containing Fullerenes

      An Approach to Nanobioparticles – Synthesis and Characterization of Fulleropeptides (pages 5291–5300)

      Mira Bjelaković, Nina Todorović and Dragana Milić

      Version of Record online: 7 AUG 2012 | DOI: 10.1002/ejoc.201200274

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      The synthesis of 11 new fulleropeptides Fp-GABAn-Glym-OtBu (n = 1–3, m = 0–2) containing 4-aminobutyric acid (GABA) and glycyl residues was achieved either by DCC/DMAP-assisted amidation or by [3+2] cycloaddition. In addition, the complete assignment of the peptides' spin systems was accomplished by extensive NMR analysis.

    18. Asymmetric Conjugate Addition

      Chiral NHC Ligands for the Copper-Catalyzed Asymmetric Conjugate Addition of Grignard Reagents (pages 5301–5306)

      Nicolas Germain, Magaly Magrez, Stefan Kehrli, Marc Mauduit and Alexandre Alexakis

      Version of Record online: 15 AUG 2012 | DOI: 10.1002/ejoc.201200479

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      Stepping up selectivity! New ligands were easily prepared by starting from cheap chiral materials. Thus, a new class of ligands and new conditions resulted in high product ee values in the copper-catalyzed conjugate addition of Grignard reagents to cyclic enones. Diverse substituted quaternary centers were formed in a very regioselective and side-reaction-free process. This was achieved with only 0.75 mol-% catalyst loading.

    19. Allylic Substitution

      Synthesis of Cyclic N-Tosyliminocarbonates by Lewis Acid Catalyzed Allylic Substitution of Trichloroacetimidates (pages 5307–5316)

      Liene Grigorjeva and Aigars Jirgensons

      Version of Record online: 8 AUG 2012 | DOI: 10.1002/ejoc.201200378

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      N-Tosyliminocarbonates were prepared by a Lewis acid catalyzed cyclization of allylic trichloroacetimidates bearing a δ-N-tosylcarbamoyloxy group. The synthetic utility of iminocarbonates was demonstrated by transforming them into 1,2-diols, cyclic carbonates, and N-tosyloxazolidinones.

    20. Hydrophobic Zipper

      Amphiphilic DNA Duplex Stabilized by a Hydrophobic Zipper (pages 5317–5323)

      Chikara Dohno, Tomonori Shibata, Masatsugu Okazaki, Shingo Makishi and Kazuhiko Nakatani

      Version of Record online: 31 JUL 2012 | DOI: 10.1002/ejoc.201200540

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      A new amphiphilic DNA consisting of dodecyl phosphotriester linkages was synthesized. The internal hydrophobic region stabilizes the duplex by hydrophobic zipper formation.

    21. Amino Acid Derivatives

      Controllable Regioselective Construction of Both Functional α-Methylene-β- and -γ-amino Acid Derivatives Through an Organocatalyzed Tandem Allylic Alkylation and Amination (pages 5324–5334)

      Feng Pan, Jian-Ming Chen, Tian-You Qin, Sean Xiao-An Zhang and Wei-Wei Liao

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200642

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      A controllable regioselective allylic alkylation and amination reaction has been developed by using α-amino nitriles for the highly selective construction of β- and γ-amino acid derivatives incorporating multiple functional groups. Subsequent multicomponent tandem reactions and transformations of the densely functionalized products were shown to readily afford a range of useful building blocks.

    22. Phenylacetylene Macrocycles

      Studies Toward the Synthesis of Phenylacetylene Macrocycle Based Rotaxane Precursors as Building Blocks for Organic Nanotubes (pages 5335–5349)

      Katy Cantin, Antoine Lafleur-Lambert, Philippe Dufour and Jean-François Morin

      Version of Record online: 1 AUG 2012 | DOI: 10.1002/ejoc.201200655

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      Synthetic efforts towards phenylacetylene macrocycle based rotaxane precursors are presented. Macrocycles with different sizes and functional groups have been prepared and attached to bulky blockers through a Sonogashira coupling reaction. Hydrolysis of the ester groups that bind the macrocycle to the rigid rod was undertaken to assess whether or not the rotaxane precursor conformation has been obtained.

    23. Tetrahydrofuran Synthesis

      Efficiency of Acid- and Mercury-Catalyzed Cyclization Reactions in the Synthesis of Tetrahydrofurans from Allylsilyl Alcohols (pages 5350–5356)

      Francisco J. Pulido, Asunción Barbero, Patricia Val, Alberto Diez and Alfonso González-Ortega

      Version of Record online: 2 AUG 2012 | DOI: 10.1002/ejoc.201200666

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      The synthesis of highly substituted tetrahydrofurans from allylsilyl alcohols is described, comparing the efficiency of the mercury- versus the acid-catalyzed cyclization.

    24. Nitrogen Heterocycles

      Synthesis and Reactivity of the 3-Substituted Isoindolinone Framework to Assemble Highly Functionalized Related Structures (pages 5357–5365)

      Carmen Petronzi, Selene Collarile, Gianluca Croce, Rosanna Filosa, Paolo De Caprariis, Antonella Peduto, Laura Palombi, Valentina Intintoli, Antonia Di Mola and Antonio Massa

      Version of Record online: 9 AUG 2012 | DOI: 10.1002/ejoc.201200678

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      Potassium carbonate efficiently catalyses the synthesis of 3-substituted isoindolinones through a tandem aldol/cyclization/rearrangement reaction. An exploration of the chemical space of the obtained isoindolinones led to diverse, highly functionalized compounds.

    25. Enzyme Models

      Two Diastereomeric Artificial Enzymes with Different Catalytic Activity (pages 5366–5372)

      Emil Lindbäck, You Zhou, Christian Marcus Pedersen and Mikael Bols

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200699

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      Two epimeric cyclodextrin aldehyde hydrates catalyse the hydrolysis of aryl glycosides, but with widely different effectiveness: for one epimer the rate is 1000 times faster, whereas it is only 100 times faster for the other.

    26. Building Blocks for Natural Products

      Synthesis of 4-Hydroxy-5-methyl- and 4-Hydroxy-6-methylcyclohexenones by PdII-Catalyzed Oxidation and Lipase-Catalyzed Hydrolysis (pages 5373–5380)

      Anne C. Meister, Martin Nieger and Stefan Bräse

      Version of Record online: 31 JUL 2012 | DOI: 10.1002/ejoc.201200704

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      A six-step synthesis of enantiomerically enriched cyclohexenone building blocks for natural products is presented. The key step is a lipase-catalyzed, monohydrolysis of a racemic diacetate, which provides two separable alcohols. Both can be converted into the desired cyclohexenones within two steps.

    27. Heterocyclic Chemistry

      Access to 2,3-Disubstituted Benzofurans through One-Pot Acid-Catalyzed Nucleophilic Substitution/TBAF-Mediated Oxacycloisomerization (pages 5381–5388)

      Chada Raji Reddy, Gaddam Krishna, Nerella Kavitha, Bellamkonda Latha and Dong-Soo Shin

      Version of Record online: 8 AUG 2012 | DOI: 10.1002/ejoc.201200708

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      A one-pot method for the synthesis of diversely 2,3-disubstituted benzofurans from propargylic alcohols is described. The strategy involves acid-catalyzed nucleophilic substitution followed by TBAF-mediated desilylative exo-dig-oxacycloisomerization.

    28. Natural Products

      Nine 2-(2-Phenylethyl)chromone Derivatives from the Resinous Wood of Aquilaria sinensis and Their Inhibition of LPS-Induced NO Production in RAW 264.7 Cells (pages 5389–5397)

      Dong Chen, Zhengren Xu, Xingyun Chai, Kewu Zeng, Yanxing Jia, Dan Bi, Zhizhong Ma and Pengfei Tu

      Version of Record online: 13 AUG 2012 | DOI: 10.1002/ejoc.201200725

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      Nine new 2-(2-phenylethyl)chromone derivatives were isolated from the resin-deposited wood of Aquilaria sinensis. Their structures were elucidated by means of NMR spectroscopy, mass spectrometry, X-ray diffraction, and chemical methods. These compounds exhibit significant inhibition of LPS-induced NO production in RAW 264.7 cells.

    29. Palladium Catalysis

      PdII-Catalyzed Conjugate Addition of Boronic Acids to Ketoglutaconic Esters toward the Synthesis of Functionalized Pyridazin-3(2H)-ones with Neuroprotective Activity (pages 5398–5405)

      Silvia Roscales, Andrea Ortega, Sagrario Martín-Aragón, Paloma Bermejo-Bescós and Aurelio G. Csákÿ

      Version of Record online: 6 AUG 2012 | DOI: 10.1002/ejoc.201200734

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      Dicationic PdII catalysts were found to be efficient for the regioselective conjugate addition of boronic acids to ketoglutaconic esters. The resulting 4-aryl-2-oxopentadienoates were transformed into pyridazin-3(2H)-ones, which simultaneously exhibited β-secretase activity, inhibition of βA aggregation, and disaggregation of pre-formed βA fibrils, and also had an ROS-scavenging profile.

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