- Copper(I)- and Phase Transfer-Catalysed Iodination of Terminal Alkynes
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A convenient synthesis of 1-iodoalk-1-ynes is reported, involving cooper(I)-catalysed iodination of terminal alkynes with molecular iodine under solid-liquid phase-transfer conditions.
- Jeffery, Tuyet
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- Halogenation of alkynes and alkynylsilanes
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Halogenation of alkynes has given 1,2-dihalogenoalkenes in good yields.Bromination of alkynylsilanes has given 1,2-dibromovinylsilanes, and reactions with iodine chloride mainly iodoalkynes.
- Al-Hassan, Mohammed I.
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Read Online
- SIRT1 Receptor agonists and drugs containing same
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The present invention belongs to the field of medicaments or nutraceutical products, and specifically relates to a compound represented by the following general formula (I), or an enantiomer, diastereomer, salt, ester, prodrug, solvate, or solvate of a salt thereof, wherein R1, R2, and R3 are as defined in the specification of the present invention. The compound prepared by the present invention brings about an effect of activating Sirt1, and can be used as a potential Sirt1 agonist. By using a hyperuricemia animal model, the compound of the present invention is found to bring about an effect of significantly lowering the level of uric acid in the body, and can be used as a potential medicament for lowering the level of uric acid or treating gout.
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Paragraph 0110-0111; 0116; 0144-0145; 0147
(2021/10/13)
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- Intramolecular Nicholas Reactions in the Synthesis of Heteroenediynes Fused to Indole, Triazole, and Isocoumarin
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The applicability of an intramolecular Nicholas reaction for the preparation of 10-membered O- and N-enediynes fused to indole, 1,2,3-triazole, and isocoumarin was investigated. The general approach to acyclic enediyne precursors fused to heterocycles inc
- Danilkina, Natalia A.,D'Yachenko, Alexander S.,Govdi, Anastasia I.,Khlebnikov, Alexander F.,Kornyakov, Ilya V.,Br?se, Stefan,Balova, Irina A.,Balova, Irina A.
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p. 9001 - 9014
(2020/08/14)
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- Synthesis and reactions of a new 1,1-disubstituted cyclopentadiene
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The synthesis and several synthetic transformations of methyl 1-benzylcyclopenta-2,4-diene-1-carboxylate are described. ARKAT USA, Inc.
- Camps, Pelayo,Gómez, Tània
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scheme or table
p. 128 - 139
(2011/05/12)
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- Pd(0)-catalyzed iodoalkynation of norbornene scaffolds: The remarkable solvent effect on reaction pathway
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A palladium-catalyzed iodoalkynation of norbornene has been realized with the use of alkynyl iodides 1, which is found to be strongly solventdependent. MeCN favors 1,7-iodoalkylation product 3 while CCl4 leads to 1,2-iodoalkylation product 4.
- Liu, Hui,Chen, Chen,Wang, Limin,Tong, Xiaofeng
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supporting information; experimental part
p. 5072 - 5075
(2011/11/29)
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- An alkynyliodide cycloaddition strategy for the construction of iodoisoxazoles
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(Figure presented) The thermally promoted cycloaddition between alkynyliodides and nitrile oxides is reported. The process offers excellent regioselectivity and a broad scope with respect to both the iodoalkynes and chloro-oximes. Further functionalization of the highly decorated iodoisoxazole motifs can be achieved via Suzuki cross-coupling.
- Crossley, James A.,Browne, Duncan L.
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supporting information; scheme or table
p. 5414 - 5416
(2010/10/04)
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- Synthesis of diacetylene-containing peptide building blocks and amphiphiles, their self-assembly and topochemical polymerization in organic solvents
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A series of functional iodoacetylenes was prepared and converted into the corresponding diacetylene-substituted amino acids and peptides via Pd/Cu-promoted sp-sp carbon cross-coupling reactions. The unsymmetrically substituted diacetylenes can be incorporated into oligopeptides without a change in the oligopeptide strand's directionality. Thus, a series of oligopeptide-based, amphiphilic diacetylene model compounds was synthesized, and their self-organization as well as their UV-induced topochemical polymerizability was investigated in comparison to related polymer-substituted macromonomers. Solution-phase IR spectroscopy, gelation experiments, and UV spectroscopy helped to confirm that a minimum of five N-H...O=C hydrogen-bonding sites was required in order to obtain reliable aggregation into stable β-sheet-type secondary structures in organic solvents. Furthermore, the non-equidistant spacing of these hydrogen-bonding sites was proven to invariably lead to β-sheets with a parallel β-strand orientation, and the characteristic IR-spectroscopic signatures of the latter in organic solution was identified. Scanning force micrographs of the organogels revealed that compounds with six hydrogen-bonding sites gave rise to high aspect ratio nanoscopic fibrils with helical superstructures but, in contrast to the related macromonomers, did not lead to uniform supramolecular polymers. The UV-induced topochemical polymerization within the β-sheet aggregates was successful, proving parallel β-strand orientation and highlighting the effect of the number and pattern of N-H...O=C hydrogen-bonding sites as well as the hydrophobic residue in the molecular structure on the formation of higher structures and reactivity.
- Jahnke, Eike,Weiss, Jan,Neuhaus, Sonja,Hoheisel, Tobias N.,Frauenrath, Holger
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experimental part
p. 388 - 404
(2009/08/07)
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- Direct C-glycosylation by indium-mediated alkynylation on sugar anomeric position
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Indium-mediated alkynylation reaction was studied for the direct preparation of C-glycosides. Easily available starting sugar derivatives with an acetyl group at the anomeric position were tested as electrophiles toward alkynylindium reagents under Barbier conditions. Good yields and stereoselectivities were observed during the reaction. The alkynylation was applied to the synthesis of an α-(1-6)-C-disaccharide analogue of isomaltoside.
- Lubin-Germain, Nadge,Baltaze, Jean-Pierre,Coste, Alexis,Hallonet, Agns,Laurano, Hugo,Legrave, Grgory,Uziel, Jacques,Aug, Jacques
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supporting information; experimental part
p. 725 - 728
(2009/04/07)
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- Ferrier-type alkynylation reaction mediated by indium
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An efficient Ferrier-type alkynylation reaction between glycals and iodoalkynes using Barbier conditions is described. These conditions require In0, In1, or In11 and lead to α-2,3-unsaturated-C-glycosides with good stereos
- Lubin-Germain, Nadege,Hallonet, Agnes,Huguenot, Florent,Palmier, Sara,Uziel, Jacques,Auge, Jacques
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p. 3679 - 3682
(2008/02/12)
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- First synthesis of Xerulin, an inhibitor of the biosynthesis of cholesterol
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Starting from L-ascorbic acid, crotonaldehyde, (trimethylsilyl)acetylene and the stannylated alcohol 15, the title compound 4 was synthesized for the first time. L-Ascorbic acid was elaborated into phosphonium bromide 19 with a high degree of Z-stereoselectivity while the other starting materials were combined for obtaining the unsaturated aldehyde 5. A Wittig reaction between this aldehyde and the ylide derived from bromide 19 provided xerulin (4) along with a mixture of isomers which was readily separable.
- Siegel, Konrad,Brückner, Reinhard
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p. 1227 - 1230
(2007/10/03)
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- New Synthetic Applications of Water-Soluble Acetate Pd/TPPTS Catalyst Generated in Situ. Evidence for a True Pd(0) Species Intermediate
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Studies on the sp-sp intermolecular coupling reactions with the palladium water-soluble catalyst prepared in situ from palladium(II) acetate and sulfonated triphenylphosphine P(C6H4-m-SO3Na)3 (TPPTS) in a homogeneous acetonitrile-water system, without Cu(I) promotor, afford diynes with moderate yields (45-65percent).Under the same conditions, the sp2-sp coupling of 2-iodophenols or 2-iodoanilines and terminal alkynes followed by intramolecular cyclization gives indolic and furanic products in good yields (60-99percent).Under these aqueous conditions, an efficient and short synthesis of eutypine illustrated the synthetic potentiality of the coupling.Furthermore, through a series of kinetic and 31P NMR experiments, we have demonstrated that a mixture of Pd(OAc)2 and TPPTS affords spontaneously a palladium(0) complex, through formation of bivalent complex Pd(OAc)2(TPPTS)2.A detailed mechanism of the reaction has been investigated thoroughly and the pertinent rate constants measured.The resulting palladium(0) complex reacts with phenyl iodide via an oxidative addition.This complex is considerably less reactive than the corresponding complex generated from PPh3, probably due to steric effects.
- Amatore, Christian,Blart, Errol,Genet, Jean Pierre,Jutand, Anny,Lemaire-Audoire, Sandrine,Savignac, Monique
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p. 6829 - 6839
(2007/10/03)
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- Terminal 1-halo and 1-pseudohalo-1-alkynes via Bis(trimethylsilyl)peroxide (BTMSPO) promoted Umpolung transfer of halides and pseudohalides
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Reaction of terminal acetylenes with readily available and inexpensive copper and zinc halides and pseudo-halides and BTMSPO has been found to be an effective and general route for obtaining, in the absence of bases and under mild conditions, 1-halo and 1-pseudohalo-1-alkynes in generally good yields.
- Casarini,Dembech,Reginato,Ricci,Seconi
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p. 2169 - 2170
(2007/10/02)
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- Reactions of Terminal Alkynes with Bis(trimethylsilyl) Peroxide and Zinc(II) Iodide: A Convenient Method for the Preparation of 1-Iodo-1-alkynes
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A convenient, mild, and general one-pot synthesis of 1-iodo-1-alkynes from terminal acetylenes, bis(trimethylsilyl) peroxide, and zinc(II) iodide in the presence of n-butyllithium is reported.
- Ricci, A.,Taddei, M.,Dembech, P.,Guerrini, A.,Seconi, G.
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p. 461 - 463
(2007/10/02)
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- SUBSTITUTION DES HALOGENO-1 ALCYNES-1 PAR LES DERIVES ORGANOMETALLIQUES DU CUIVRE. ACCES A UNE NOUVELLE CLASSE DE SYNTHONS: APPLICATION A LA SYNTHESE DU BOMBYKOL
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1-Bromo- and 1-iodo-1-alkynes are alkylated by organocopper(I) compounds.Alkenylcopper(I) derivatives undergo substitution with retention of configuration leading to conjugated and functional enynes, from which conjugated dienes can be obtained.
- Commercon, A.,Normant, J. F.,Villieras, J.
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p. 1215 - 1222
(2007/10/02)
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