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Indole
Terms modified by Indole Selected AbstractsWater-Accelerated Cationic ,-(7- endo) Cyclisation: Application to Indole-Based Peri-Annulated Polyheterocycles,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 26 2010Mohammad Saifuddin Abstract An efficient and versatile method for the synthesis of indole-based polycyclic indolo-benzazepine and its derivatives through water-accelerated cationic ,-cyclisation is described. The strategy involves condensation of arylamine moieties linked to C-4 in indole/azaindole systems with arylaldehydes in water containing catalytic amount of Brønsted acids. The C,C bond formation in water is complete within 10,30 min, furnishing the title compounds in excellent yields and purities, whereas in organic solvents 10,12 h are required. Furthermore, aldehydes both with electron-donating and-withdrawing substituents facilitate the ,-cyclisation equally. [source] Indole in DNA: Comparison of a Nucleosidic with a Non-Nucleosidic DNA Base SubstitutionEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2009Janez Barbaric Abstract The synthetic incorporation of indole as an artificial DNA base into oligonucleotides by two different structural approaches is described. For both types of modification, the indole moiety is attached through the C-3 position to the oligonucleotides. As a mimic of natural nucleosides, the indole nucleoside of ,-2,-deoxyribofuranoside (In) was synthesized. The corresponding In-modified duplexes were compared with duplexes that contained the indole group connected through (S)-3-amino-1,2-propanediol as an acyclic linker between the phosphodiester bridges of the oligonucleotides. This linker was tethered to the C-3 position of the indole heterocycle either directly (In,) or by a carbamate function (In,). The melting temperatures of the corresponding indole-modified DNA duplexes were measured and compared. Interestingly, not only the In, and In, modifications but also the natural-like In base surrogate destabilize the DNA duplex strongly. This result supports our approach to apply the acyclic glycol linker to incorporate aromatic molecules as artificial DNA base substitutions. The major advantage of acyclic glycol linkers [such as the applied (S)-3-amino-1,2-propanediol] is that the corresponding modifications are synthetically more easily and readily accessible, as it avoids the preparation of the nucleosidic bond and the separation and purification of the ,- and ,-anomers. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] 2H -Pyrrole Derivatives from an Aza-Nazarov Reaction Cascade Involving Indole as the Neutral Leaving GroupEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 21 2008Nugzar Ghavtadze Abstract Trifluoromethyl-substituted N -indolinyl-1-aza-1,4-dien-3-ones 4, which are accessible in good yields from indolinylimino esters 6 in a two-step procedure, undergo a novel type of aza-Nazarov cyclization if treated with strong acids to give the hitherto unknown 3-hydroxy-5H -pyrrole derivatives 8a,p. The solvent-free polyphosphoric acid/acyl anhydride system as the acidic reaction medium is especially efficient and requires only short reaction times. According to quantum chemical calculations the key step in the reaction cascade is the cleavage of the N,N bond of the hydrazone fragment of a protonated N -(indolin-1-yl)-1-aza-1,4-dien-3-one intermediate such as 10. This intermediate releases 3H -indole as an unusual, but very efficient neutral leaving group. Several 1-aza-1,4-dien-3-ones 4 and some 3-hydroxy-5H -pyrrole derivatives 8 were characterized by X-ray diffraction.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Indole as an intercellular signal in microbial communitiesFEMS MICROBIOLOGY REVIEWS, Issue 4 2010Jin-Hyung Lee Abstract Bacteria can utilize signal molecules to coordinate their behavior to survive in dynamic multispecies communities. Indole is widespread in the natural environment, as a variety of both Gram-positive and Gram-negative bacteria (to date, 85 species) produce large quantities of indole. Although it has been known for over 100 years that many bacteria produce indole, the real biological roles of this molecule are only now beginning to be unveiled. As an intercellular signal molecule, indole controls diverse aspects of bacterial physiology, such as spore formation, plasmid stability, drug resistance, biofilm formation, and virulence in indole-producing bacteria. In contrast, many non-indole-producing bacteria, plants and animals produce diverse oxygenases which may interfere with indole signaling. It appears indole plays an important role in bacterial physiology, ecological balance, and possibly human health. Here we discuss our current knowledge and perspectives on indole signaling. [source] Highly Enantioselective Friedel,Crafts Reaction of Indole with Alkylidenemalonates Catalyzed by Heteroarylidene Malonate-Derived Bis(oxazoline) Copper(II) ComplexesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 18 2009Yan-Jin Sun Abstract A series of cheap and easily accessible heteroarylidenemalonate-derived bis(oxazoline) ligands 1 and 2 were synthesized and their copper(II) complexes were applied to the catalytic Friedel,Crafts reaction between indoles and diethyl alkylidenemalonates, Excellent asymmetric enantioselectivities were afforded for the S -enantiomer (up to >99% ee) in isobutyl alcohol, and the R -enantiomer (up to 96.5% ee) in dichloromethane. [source] Indole, a core nucleus for potent inhibitors of tubulin polymerization,MEDICINAL RESEARCH REVIEWS, Issue 2 2007Andrea Brancale Abstract Microtubules are the basic components of cell structure, which take part in a wide number of pivotal cellular functions. Drugs that are able to modulate the microtubule assembly either by inhibition of tubulin polymerization or by blocking microtubule disassembly are of great interest in anti-cancer therapy. Several tubulin polymerization inhibitors characterized by the presence of an indole nucleus have been obtained from natural sources or have been prepared by semi-synthesis. In the last decade an ever increasing number of synthetic indoles have been reported. We have reviewed anti-tubulin agents obtained by synthesis having an indole as core nucleus. The synthesis, the biological activity, and the structure,activity relationship aspects of 3-formyl-2-phenylindoles, heterocombretastatins, diarylindoles, 2-aroylindoles, D-24851, 2-aryl-3-aroylindoles, 3-aroyl- and 1-aroylindoles, and arylthioindoles are discussed. © 2006 Wiley Periodicals, Inc. Med Res Rev [source] Indole and 7-hydroxyindole diminish Pseudomonas aeruginosa virulenceMICROBIAL BIOTECHNOLOGY, Issue 1 2009Jintae Lee Summary Indole is an extracellular biofilm signal for Escherichia coli, and many bacterial oxygenases readily convert indole to various oxidized compounds including 7-hydroxyindole (7HI). Here we investigate the impact of indole and 7HI on Pseudomonas aeruginosa PAO1 virulence and quorum sensing (QS)-regulated phenotypes; this strain does not synthesize these compounds but degrades them rapidly. Indole and 7HI both altered extensively gene expression in a manner opposite that of acylhomoserine lactones; the most repressed genes encode the mexGHI-opmD multidrug efflux pump and genes involved in the synthesis of QS-regulated virulence factors including pyocyanin (phz operon), 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS) signal (pqs operon), pyochelin (pch operon) and pyoverdine (pvd operon). Corroborating these microarray results, indole and 7HI decreased production of pyocyanin, rhamnolipid, PQS and pyoverdine and enhanced antibiotic resistance. In addition, indole affected the utilization of carbon, nitrogen and phosphorus, and 7HI abolished swarming motility. Furthermore, 7HI reduced pulmonary colonization of P. aeruginosa in guinea pigs and increased clearance in lungs. Hence, indole-related compounds have potential as a novel antivirulence approach for the recalcitrant pathogen P. aeruginosa. [source] Gold-Catalyzed Cycloisomerization Reactions of 2-Tosylaminophenylprop-1-yn-3-ols as a Versatile Approach for Indole Synthesis,ANGEWANDTE CHEMIE, Issue 27 2010Prasath Kothandaraman Gold und Indole: Die Titelreaktion verläuft vermutlich über ein Vinyl-Gold-Intermediat, das in,situ durch Einwirkung von AuCl/AgOTf entsteht. Unter den Reaktionsbedingungen werden Inden-anellierte und 2,3-disubstituierte Indolderivate in Ausbeuten bis 94,% erhalten (siehe Schema). [source] Orthogonal Enantioselectivity Approaches Using Homogeneous and Heterogeneous Catalyst Systems: Friedel,Crafts Alkylation of Indole,ANGEWANDTE CHEMIE, Issue 26 2010Young Kim Dr. Mit Träger oder ohne? Komplementäre homogene und heterogene Katalysatorsysteme für die asymmetrische Friedel-Crafts-Alkylierung von Indolen mit Nitroalkenen wurden entwickelt. Je nach Reaktionsbedingungen (d.,h. mit oder ohne Zugabe eines festen Trägers; siehe Schema) war so jedes der beiden enantiomeren Produkte 2 selektiv zugänglich. [source] Direct Alkynylation of Indole and Pyrrole Heterocycles,ANGEWANDTE CHEMIE, Issue 49 2009Jonathan Dreifach einfach: Die einzigartigen Eigenschaften von Benziodoxolonalkinylperiodinan 1 und Goldkatalysatoren ermöglichten die Entwicklung einer einfach auszuführenden Reaktion (bei Raumtemperatur, ohne absolute Lösungsmittel oder inerte Bedingungen, mit käuflichem Katalysator), durch die sich Silylacetylen-Reste in hohen Ausbeuten einführen lassen. Als Substrate eignen sich vielfältige Indole und Pyrrole mit einem breiten Spektrum an funktionellen Gruppen (siehe Schema). [source] Iridium-Catalyzed Regio- and Enantioselective N-Allylation of Indoles,ANGEWANDTE CHEMIE, Issue 42 2009Iridium verschmäht C: Hoch regio- und enantioselektive iridiumkatalysierte N-Allylierungen von Indolen ergänzen üblichere Umsetzungen, in denen die Indole als Kohlenstoffnucleophile wirken (siehe Schema). Die Reaktionen führen zu stark enantiomerenangereicherten N -Allylindolen, aus denen sich leicht enantiomerenangereicherte 3-(1H -Indol-1-yl)- N -methyl-3-arylpropan-1-amine, Dihydropyrrolo[1,2- a]indole und (Indol-1-yl)propansäurederivate erhalten lassen. [source] Asymmetric Construction of Polycyclic Indoles through Olefin Cross-Metathesis/Intramolecular Friedel,Crafts Alkylation under Sequential Catalysis,ANGEWANDTE CHEMIE, Issue 40 2009Quan Cai Abgekürzt: Eine hocheffiziente Kaskadenreaktion (siehe Schema) liefert mit ausgezeichneter Enantioselektivität polycyclische Indole. Die Verknüpfung der beiden Stufen in einer sequentiellen Katalyse ermöglicht den Einsatz leichter zugänglicher Ausgangsmaterialien und macht die Synthese praktikabler. Boc=tert -Butoxycarbonyl. [source] Indole- and carbazole-substituted pyridinium iodide salts: a rare case of conformational isomerism in crystalsACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2001Zheng Wang A series of indole- and carbazole-substituted pyridinium iodide salts has been synthesized and characterized. X-ray analysis revealed that the iodide salt of the indole-substituted cation (E)-4-(1H -indol-3-ylvinyl)- N -methylpyridinium (IMPE+), C16H15N2+·I,, (I), has two polymorphic modifications, (Ia) and (Ib), and a hemihydrate structure, C16H15N2+·I,·0.5H2O, (II). Until now, only one crystal modification has been identified for the (E)-4-(9-ethyl-9H -carbazol-3-ylvinyl)- N -methylpyridinium (ECMPE+) iodide salt, C22H21N2+·I,, (III). Crystals of (Ia) and (Ib) comprise stacks of antiparallel cations with iodide anions located in the channels between the stacks. Due to the presence of the water molecules, the packing in (II) is quite different to that found in (Ia) and (Ib), and positional disorder involving a statistical superposition of two rotamers of IMPE+, with different orientations of the indole fragment, was found. Crystals of (III) contain two independent ECMPE+ rotamers with different orientations of their carbazole substituents. The cations are packed in stacks, with the iodide anions located in the channels between the stacks. In (III), the iodide was found to be disordered over two sites, with occupancies of 0.83 and 0.17. [source] ChemInform Abstract: Iron Salt-Catalyzed Cascade Type One-Pot Double Alkylation of Indole with Vinyl Ketones.CHEMINFORM, Issue 42 2010Jun-ka Kobayashi No abstract is available for this article. [source] ChemInform Abstract: Oxazolidin-2-one as Efficient Ligand for the Copper-Catalyzed N-Arylation of Pyrrole, Imidazole and Indole.CHEMINFORM, Issue 39 2010Hengchang Ma Abstract The easy preparation, broad substrate applicability and substituent compatibility of this catalyst system renders the oxazolidine-2-one system great advantages over previous Cu-catalyzed N-arylation methods. [source] ChemInform Abstract: Gallium Trichloride-Catalyzed Conjugate Addition of Indole and Pyrrole to ,,,-Unsaturated Ketones in Aqueous Media.CHEMINFORM, Issue 42 2009Rong Xu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Efficient Chirality Switching in the Asymmetric Addition of Indole to N-Tosylarylimines in the Presence of Axially Chiral Cyclometalated Bidentate N-Heterocyclic Carbene Palladium(II) Complexes.CHEMINFORM, Issue 32 2009Zhen Liu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Sc(OTf)3 -Catalyzed or tBuOK-Promoted Tandem Reaction of 2-(2-(Alkynyl)benzylidene)malonate with Indole.CHEMINFORM, Issue 42 2008Ke Gao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Catalytic Reaction of Aryldiazoacetates with Indole and Its Derivatives: Profound Effect of N-1 Substitutent on the Reaction Pathways.CHEMINFORM, Issue 35 2008Xue-Jing Zhang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis of Novel Indole-Based Ring Systems by Acid-Catalyzed Condensation from ,-Amino Aldehydes and L-Trp-OMe.CHEMINFORM, Issue 31 2008Paolo Grieco Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Study on the Conjugate Addition of Indole with 1,5-Diaryl-1,4-pentadien-3-ones Catalyzed by AlCl3 under Ultrasonication.CHEMINFORM, Issue 23 2008Ji-Tai Li Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis of Functionalized Phosphonates by Three-Component Reaction Between Phosphites, Dialkyl Acetylenedicarboxylates and Pyrrole, Indole or Benzotriazole.CHEMINFORM, Issue 47 2007Mohammad Anary-Abbasinejad Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Reactions of 3-(Polyfluoroacyl)chromones with Indole and N-Methylindole.CHEMINFORM, Issue 45 2007V. Ya. Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis and SAR of Selective Benzothiophene, Benzofuran, and Indole-Based Peroxisome Proliferator-Activated Receptor , Agonists.CHEMINFORM, Issue 43 2007Gary F. Filzen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Efficient Synthesis of Medium-Sized Rings Incorporating Indole or Pyrrole Units by Samarium Diiodide Induced Cyclizations.CHEMINFORM, Issue 11 2007Virginie Blot Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Potassium Carbonate as a Base for the N-Alkylation of Indole and Pyrrole in Ionic Liquids.CHEMINFORM, Issue 29 2006Yogesh R. Jorapur Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] CAN- and Iodine-Catalyzed Reaction of Indole or 1-Methylindole with ,,,-Unsaturated Ketone or Aldehyde.CHEMINFORM, Issue 18 2006Shengkai Ko Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] I2 -Catalyzed Michael Addition of Indole and Pyrrole to Nitroolefins.CHEMINFORM, Issue 12 2006Chunchi Lin Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Sequential Sonogashira and Suzuki Cross-Coupling Reactions in the Indole and Indazole Series.CHEMINFORM, Issue 33 2005Bernhard Witulski Abstract For Abstract see ChemInform Abstract in Full Text. [source] Novel Synthesis of Bicycles with Fused Pyrrole, Indole, Oxazole, and Imidazole Rings.CHEMINFORM, Issue 20 2005Alan R. Katritzky Abstract For Abstract see ChemInform Abstract in Full Text. [source] | ||||||||||||||||||||||||||||||||||||||||