- Substrate-Inspired Fragment Merging and Growing Affords Efficacious LasB Inhibitors
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Extracellular virulence factors have emerged as attractive targets in the current antimicrobial resistance crisis. The Gram-negative pathogen Pseudomonas aeruginosa secretes the virulence factor elastase B (LasB), which plays an important role in the infection process. Here, we report a sub-micromolar, non-peptidic, fragment-like inhibitor of LasB discovered by careful visual inspection of structural data. Inspired by the natural LasB substrate, the original fragment was successfully merged and grown. The optimized inhibitor is accessible via simple chemistry and retained selectivity with a substantial improvement in activity, which can be rationalized by the crystal structure of LasB in complex with the inhibitor. We also demonstrate an improved in vivo efficacy of the optimized hit in Galleria mellonella larvae, highlighting the significance of this class of compounds as promising drug candidates.
- Kaya, Cansu,Walter, Isabell,Yahiaoui, Samir,Sikandar, Asfandyar,Alhayek, Alaa,Konstantinovi?, Jelena,Kany, Andreas M.,Haupenthal, J?rg,K?hnke, Jesko,Hartmann, Rolf W.,Hirsch, Anna K. H.
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supporting information
(2021/12/16)
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- A facile microwave assisted synthesis and structure elucidation of (3R)-3-alkyl-4,1-benzoxazepine-2,5-diones by crystallographic, spectroscopic and DFT studies
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The use of microwave (MW) irradiation in organic synthesis has become increasingly popular within the pharmaceutical and academic arenas because it is a new enabling technology for drug discovery and development. It is a rapid way of synthesis, which involves faster reaction rates and high selectivity to conventional heating method of syntheses. The MW-assisted 7-exo-tet cyclization of N-acylanthranilic acids afforded (3R)-3-alkyl-4,1-benzoxazepines-2,5-diones in very short duration (20 min) with extraordinary high yields in comparison to conventional heating mode of synthesis. The method development, comparative yields of MW-assisted and thermal method of syntheses, crystallographic, spectroscopic and density functional theory (DFT) studies are reported herein. Four novel compounds with chemical formulas C10H9BrClNO3 5m, C19H19NO3 6e, C13H14ClNO3 6h and C12H11Br2NO3 6h were synthesized, validated by 1HNMR, 13CNMR, FT-IR, UVVis, EIMS spectroscopic techniques and confirmed by using single crystal X-ray diffraction (SC-XRD) study. The DFT and TDDFT calculations at B3LYP/6-311 + G(d,p) level of theory were performed for comparative analysis of spectroscopic data, optimized geometries, frontier molecular orbitals (FMOs), natural bond orbital (NBO) analysis and nonlinear optical (NLO) properties of 5m, 6e, 6h and 6o. Overall, experimental findings were supported nicely by corresponding DFT computed results. The NBO analysis confirmed that the presence of non-covalent interactions, hydrogen bonding and hyper- conjugative interactions are pivotal cause for the existence of 5m, 6e, 6h and 6o in the solid-state. NLO analysis showed that 5m, 6e, 6h and 6o have significant NLO properties as compared to prototype standard compound which disclosed their potential for technology related applications.
- Raza, Abdul Rauf,Nisar, Bushra,Khalid, Muhammad,Gondal, Humaira Yasmeen,Khan, Muhammad Usman,de Alcantara Morais, Sara Figueirêdo,Tahir, Muhammad Nawaz,Braga, Ataualpa Albert Carmo
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-
- A Straightforward Homologation of Carbon Dioxide with Magnesium Carbenoids en Route to α-Halocarboxylic Acids
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The homologation of carbon dioxide with stable, (enantiopure) magnesium carbenoids constitutes a valuable method for preparing α-halo acid derivatives. The tactic features a high level of chemocontrol, thus enabling the synthesis of variously functionalized analogues. The flexibility to generate magnesium carbenoids through sulfoxide-, halogen- or proton- Mg exchange accounts for the wide scope of the reaction. (Figure presented.).
- Monticelli, Serena,Urban, Ernst,Langer, Thierry,Holzer, Wolfgang,Pace, Vittorio
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p. 1001 - 1006
(2019/01/30)
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- Di(1-naphthyl) methanol ester of carboxylic acids for absolute stereochemical determination
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The absolute stereochemistry of chiral carboxylic acids is determined as a di(1-naphthyl)methanol ester derivative. Computational scoring of conformations favoring either P or M helicity of the naphthyl groups, capable of exciton-coupled circular dichroic coupling, leads to a predicted stereochemistry for the derivatized carboxylic acids.
- Zhang, Jun,Sheng, Wei,Gholami, Hadi,Nehira, Tatsuo,Borhan, Babak
-
supporting information
p. 141 - 146
(2017/11/13)
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- Preparation method of alpha-chloro carboxylic acid
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The invention discloses a preparation method of alpha-chloro carboxylic acid. According to the preparation method, amino acids are dissolved into hydrochloric acid to form a homogeneous solution; thenobtained homogeneous solution and a sodium nitrite water solution are simultaneously pumped into a mixing valve through an injection pump A and an injection pump B of a micro-channel reaction apparatus; after the solutions are fully mixed, the mixed solution is pumped into a micro reactor of the micro-channel reaction apparatus to carry out reactions at a constant flowing speed, and the flow-outliquid namely alpha-chloro carboxylic acid is collected. The provided method realizes the continuous production of alpha-chloro carboxylic acid; furthermore, the product quality is good, the operationis simple, the using amount of raw materials is little, the process is safe, the method is green and environmentally friendly, energy is saved, the efficiency is high, and thus the method is suitablefor industrial production.
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-
Paragraph 0056; 0057
(2018/04/26)
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- Synthesis and anti-parasitic activity of C-benzylated (N-arylcarbamoyl)alkylphosphonate esters
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Unexpected substituent-dependent regioselectivty challenges in the synthesis of C-benzylated (N-arylcarbamoyl)phosphonate esters have been resolved. The C-benzylated N-furfurylcarbamoyl derivative showed low micromolar PfLDH inhibition, while one of the C-benzylated N-arylcarbamoyl analogues was active against Nagana Trypanosoma brucei parasites which are responsible for African trypanosomiasis in cattle.
- Adeyemi, Christiana M.,Isaacs, Michelle,Mnkandhla, Dumisani,Klein, Rosalyn,Hoppe, Heinrich C.,Krause, Rui W.M.,Lobb, Kevin A.,Kaye, Perry T.
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p. 1661 - 1667
(2017/03/08)
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- Enantioselective organocatalytic synthesis of 2-oxopiperazines from aldehydes: Identification of the elusive epoxy lactone intermediate
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An organocatalytic linchpin catalysis approach was envisaged to convert simple aldehydes into enantioenriched 2-oxopiperazines. A four-step reaction sequence (chlorination, oxidation, substitution, and cyclization) was developed and led to different substitution patterns in high yields and selectivities. The reaction mechanism was studied, and the previously elusive epoxy lactone intermediate was identified by HRMS.
- Kaplaneris, Nikolaos,Spyropoulos, Constantinos,Kokotou, Maroula G.,Kokotos, Christoforos G.
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p. 5800 - 5803
(2016/11/29)
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- Chiral Pool-Based Synthesis of Naphtho-Fused Isocoumarins
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A variety of chiral derivatives of benzo[d]naphtho[1,2-b]pyran-6-one were prepared in a single step by Et3N-mediated condensation of homophthalic anhydride with different derivatives of (S)-amino acid chlorides at -5 °C by employing a chiral pool methodology. Chirality 27:951-957, 2015.
- Raza, Abdul Rauf,Saddiqa, Aisha,?akmak, Osman
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p. 951 - 957
(2015/11/16)
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- Chiron based synthesis of isocoumarins: Reactivity of α-substituted carboxylic acids
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The asymmetric synthesis of a novel (S)-isocoumarin has been attempted in a single step by the coupling of homophthalic acid with (S)-N-protected amino acids and α-chloroacids at high temperature by exploiting a chiral pool methodology. The coupling of homophthalic acid with N-protected (S)-amino acids gave exclusion of the carboxyl/alkyl group. However, coupling of homophthalic acid with α-chloroacids afforded asymmetric isocoumarins in high yield.
- Saddiqa, Aisha,Raza, Abdul R.,Black, David Stc.,Kumar, Naresh
-
supporting information
p. 736 - 743
(2014/06/09)
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- Visible light photoredox-catalysed intermolecular radical addition of α-halo amides to olefins
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We present α-chloro amides as a new class of α-acetyl radical precursors, which undergo a tin-free, photoredox-catalysed intermolecular α-alkylation with various olefins exclusively in an anti-Markovnikov fashion. The reaction represents a reductive atom
- Nakajima, Masaki,Lefebvre, Quentin,Rueping, Magnus
-
supporting information
p. 3619 - 3622
(2014/04/03)
-
- Enantioselective protonation of α-hetero carboxylic acid-derived ketene disilyl acetals under chiral ionic Bronsted acid catalysis
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Highly enantioselective protonation of α-halo and alkoxy carboxylic acid-derived ketene disilyl acetals is achieved by using P-spiro chiral diaminodioxaphosphonium barfate as a Bronsted acid catalyst, where the enantiofacial discrimination by the catalyst mainly stems from the recognition of the electronic difference between two substituents on the ketene disilyl acetal.
- Uraguchi, Daisuke,Kizu, Tomohito,Ohira, Yuki,Ooi, Takashi
-
supporting information
p. 13489 - 13491
(2015/01/09)
-
- Stereoselective synthesis of (3r)-3-alkyl-4,1-benzoxazepine-2,5-diones
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Novel 3-alkyl-4,1-benzoxazepine-2,5-diones were synthesized in good ee exploiting the chiral pool methodology, an economical way of asymmetric synthesis. Various anthranilic acids are coupled with different α-haloacids to afford N-acylated anthranilic aci
- Nisar, Bushra,Raza, Abdul Rauf,Black, David Stc.,Kumar, Naresh,Tahir, Muhammad Nawaz
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p. 865 - 870
(2014/01/06)
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- Synthesis of libraries of peptidomimetic compounds containing a 2-oxopiperazine unit in the main chain
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Peptoid libraries have been shown to be a useful source of protein-binding agents. However, simple linear peptoids lack conformational constraints, which may limit their binding affinity for proteins. Here we report facile chemistry for the assembly of 2-oxopiperazine rings into the main chain of peptoid-like oligomers, thus rigidifying the structure. This modified sub-monomer synthesis is suitable for the creation of high quality combinatorial libraries. The Royal Society of Chemistry 2013.
- Suwal, Sujit,Kodadek, Thomas
-
supporting information
p. 2088 - 2092
(2013/05/09)
-
- Conformational preference in bis(porphyrin) tweezer complexes: A versatile chirality sensor for α-chiral carboxylic acids
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Metallated porphyrin tweezers have demonstrated a remarkable ability to function as reporters of absolute stereochemistry for a number of different classes of organic molecules. Flexibility in binding, however, can result in an ensemble of different Exciton Coupled Circular Dichroism (ECCD) active conformations that could lead to variable results. Linker flexibility was found to be a key determinant of binding conformation. Experimental results indicate that a balance between linker flexibility and rigidity could yield an optimum porphyrin tweezer that stabilizes a common conformation for all bound chiral guests. This leads to a more simplified approach to absolute stereochemical determination of asymmetry for small organic molecules. This was demonstrated by the use of a C3-linked zincated porphyrin tweezer that yields a common conformational preference for a variety of α-chiral carboxylic acids derivatized with a diamine carrier. Copyright
- Tanasova, Marina,Borhan, Babak
-
supporting information; experimental part
p. 3261 - 3269
(2012/07/01)
-
- A substrate-driven approach to determine reactivities of α,β-unsaturated carboxylic esters towards asymmetric bioreduction
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The degree of C=C bond activation in the asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases was studied, and general recommendations to render these "borderline-substrates" more reactive towards enzymatic reduction are proposed. The concept of "supported substrate activation" was developed. In general, an additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates, and α-cyano groups showed little effect. The alcohol moiety of the ester functionality was found to have a strong influence on the reaction rate. Overall, activities were determined by both steric and electronic effects. Biotransformation: The asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases could be tuned by varying the degree of C=C bond activation (see scheme). An additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates. Copyright
- Tasnádi, Gábor,Winkler, Christoph K.,Clay, Dorina,Sultana, Nargis,Fabian, Walter M. F.,Hall, Mélanie,Ditrich, Klaus,Faber, Kurt
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supporting information; experimental part
p. 10362 - 10367
(2012/10/08)
-
- Triazolium Carbene Catalysts and Stereoselective Bond Forming Reactions Thereof
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Provided herein are triazolium carbine catalysts useful for asymmetric hydration, fluorination, and deuteration, and processes for their preparation. Also provided are synthetic reactions in which these catalysts are used, in particular, in stereoselective formation of carbon-chlorine, carbon-hydrogen, carbon-fluorine, and carbon-deuterium bonds.
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Page/Page column 11
(2011/10/04)
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- Enantio and diastereoselective addition of phenylacetylene to racemic α-chloroketones
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In this report, we have presented the first diastereoselective addition of phenylacetylene to chiral racemic chloroketones. The addition is controlled by the reactivity of the chloroketones that allowed the stereoselective reaction to be performed at -20
- Alesi, Silvia,Emer, Enrico,Capdevila, Montse Guiteras,Petruzziello, Diego,Gualandi, Andrea,Cozzi, Pier Giorgio
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scheme or table
p. 5298 - 5314
(2011/08/06)
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- Biocatalyzed enantioselective reduction of activated C=C bonds: Synthesis of enantiomerically enriched α-halo-β-arylpropionic acids
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The enantioselective biocatalyzed reduction of the C=C bond of some (Z)-methyl α-halo-β-arylacrylates was investigated. The reaction was performed by baker's yeast fermentation and Old Yellow Enzymes 1-3 mediated biotransformations. The final products wer
- Brenna, Elisabetta,Gatti, Francesco G.,Manfredi, Alessia,Monti, Daniela,Parmeggiani, Fabio
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experimental part
p. 4015 - 4022
(2011/09/15)
-
- Synthesis of azide-alkyne fragments for "Click" chemical applications. Part 2. Formation of oligomers from orthogonally protected chiral trialkylsilylhomopropargyl azides and homopropargyl alcohols
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(Chemical Equation Presented) A small library of chiral, β3-substituted homopropargyl alcohols and chiral β3-substituted trimethylsilylhomopropargyl azides were generated starting from natural L-amino acids. The free alkynes and azides were then coupled, using a Huisgen 1,3-dipolar cycloaddition, to provide chiral oligomeric 1,4-disubstituted-1,2,3-triazoles as potential peptidomimetic compounds. The work is an extension to the previous synthesis of racemic, orthogonally protected 1,4-disubstituted-1,2,3-triazoles from the corresponding α-substituted propargyl alcohols and α-substituted trialkylsilylpropargyl azides.
- Montagnat, Oliver D.,Lessene, Guillaume,Hughes, Andrew B.
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scheme or table
p. 390 - 398
(2010/03/30)
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- Stereoselective synthesis of chiral 4-(1-Chloroalkyl)-β-lactams starting from amino acids and their transformation into functionalized chiral azetidines and pyrrolidines
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Chiral short-chain α-chloroaldehydes were prepared starting from enantiomerically pure amino acids in a three-step approach, thus providing a practical synthetic alternative for known organocatalytic α-chlorination procedures. The latter aldehydes proved
- Dekeukeleire, Stijn,Dhooghe, Matthias,Toernroos, Karl W.,De Kimpe, Norbert
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experimental part
p. 5934 - 5940
(2010/11/05)
-
- SUBSTITUTED PHENYLLUREAS AND PHENYLAMIDES AS VANILLOID RECEPTOR LIGANDS
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The invention relates to substituted phenylureas and phenylamides of formula (I), to processes for the preparation thereof, to pharmaceutical compositions containing these compounds and also to the use of these compounds for preparing pharmaceutical compositions.
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Page/Page column 116
(2010/11/18)
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- An unusual conformation of α-haloamides due to cooperative binding with zincated porphyrins
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CD and NMR spectroscopic evidence of cooperative binding between an α-halogen atom and a carboxamide group with a zinc porphyrin leads to an unprecedented conformation for the determination of the absolute stereochemistry of α-haloamides (α-halocarboxylic acids derivatized with 1,4-phenylenediamine) through the use of exciton-coupled circular dichroism (ECCD). With the use of chiral lactams, whose rotomeric contributions are minimized, both ECCD and NMR spectroscopy demonstrate that the porphyrin favors binding to the side of the sterically more demanding halogen atom as compared to the smaller hydrogen atom. In all, the data is strongly suggestive of an unusual conformation not observed before for α-chiral amides. A mnemonic for determining the absolute stereochemistry of α-halogenated carboxylic acids is provided.
- Tanasova, Marina,Yang, Qifei,Olmsted, Courtney C.,Vasileiou, Chrysoula,Li, Xiaoyong,Anyika, Mercy,Borhan, Babak
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supporting information; experimental part
p. 4242 - 4253
(2011/02/25)
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- Vanilloid receptor ligands, pharmaceutical compositions containing them, process for making them and use thereof for treating pain and other conditions
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Compounds corresponding to formula I: which act as vanilloid receptor ligands, pharmaceutical compositions containing such compounds, a process for the producing such compounds, and the use thereof to treat or inhibit pain and/or various other disorders or conditions.
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Page/Page column 37-38
(2008/12/08)
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- Quantitation of phenylalanine and its trans-cinnamic, benzoic and hippuric acid metabolites in biological fluids in a single GC-MS analysis
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We describe a sensitive, simple and convenient stable isotope dilution assay developed to study endogenous metabolism of administered stable isotope-labeled phenylalanine (Phe) in phenylketonuric (PKU) mice treated experimentally with phenylalanine ammoni
- Sarkissian, Christineh N.,Scriver, Charles R.,Mamer, Orval A.
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p. 811 - 817
(2008/02/09)
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- Enantioselective protonation of catalytically generated chiral enolates as an approach to the synthesis of α-chloroesters
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Treatment of α,α-dichloroaldehydes with various phenols in the presence of chiral triazolium salt catalysts and excess base results in the synthesis of α-chloro aryl esters in good yield and enantioselectivity. The reaction is tolerant of various function
- Reynolds, Nathan T.,Rovis, Tomislav
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p. 16406 - 16407
(2007/10/03)
-
- Design and synthesis of chromogenic thiopeptolide substrates as MetAPs active site probes
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Twenty one chromogenic thiopeptolide substrates were designed and synthesized as the active site probes and analyzed with each S1 site of mutant residues and enzymes of wild-type MetAP1s. The preliminary enzymatic experiments indicate that cysteine 70 or 202, at either Escherichia coli or human MetAP1, played a crucial role in the methionine hydrolysis.
- Cui, Yong-Mei,Li, Jing-Ya,Chen, Ling-Ling,Li, Jia,Ye, Qi-Zhuang,Nan, Fa-Jun
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p. 2853 - 2861
(2007/10/03)
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- Process for producing optically active carboxylic acid subtituted in 2-position
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A nitrous acid salt is added at a temperature of 10 to 80° C. to an aqueous solution which contains an optically active 2-aminocarboxylic acid (4) and a protonic acid, the amount of the latter acid being 1 to 3 equivalents to the former, and which has a proton concentration of 0.5 to 2 mol/kg to conduct a reaction to thereby produce an optically active 2-hydroxycarboxylic acid (1). Thionyl chloride and a basic compound are caused to act on the compound (1) to chlorinate it and simultaneously invert the configuration in the 2-position. Thus, an optically active 2-chlorocarboxylic acid chloride (5) is induced. The compound (5) is hydrolyzed to induce an optically active 2-chlorocarboxylic acid (2). The compound (2) is reacted with a thioacetic acid salt to incorporate an acetylthio group thereinto and simultaneously invert the configuration in the 2-position to thereby produce an optically active 2-acetylthiocarboxylic acid (3). 1
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- Isoquinolines useful as analgesics
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PCT No. PCT/SE97/00315 Sec. 371 Date Oct. 6, 1997 Sec. 102(e) Date Oct. 6, 1997 PCT Filed Feb. 25, 1997 PCT Pub. No. WO97/31940 PCT Pub. Date Sep. 4, 1997The present invention is directed to compounds that act as analgesics and that have the structure of
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- Pseudoephedrine as a practical chiral auxiliary for the synthesis of highly enantiomerically enriched carboxylic acids, alcohols, aldehydes, and ketones
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The use of pseudoephedrine as a practical chiral auxiliary for asymmetric synthesis is described in full. Both enantiomers of pseudoephedrine are inexpensive commodity chemicals and can be N-acylated in high yields to form tertiary amides. In the presence of lithium chloride, the enolates of the corresponding pseudoephedrine amides undergo highly diastereoselective alkylations with a wide range of alkyl halides to afford α-substituted products in high yields. These products can then be transformed in a single operation into highly enantiomerically enriched carboxylic acids, alcohols, aldehydes, and ketones.
- Myers, Andrew G.,Yang, Bryant H.,Chen, Hou,McKinstry, Lydia,Kopecky, David J.,Gleason, James L.
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p. 6496 - 6511
(2007/10/03)
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- A Highly Efficient Synthesis of the Anthelmintic Cyclooctadepsipeptide PF1022A
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The potent anthelmintic cyclooctadepsipeptide PF1022A was synthesized by a series of fragment condensations starting from the known (S)-2-chloropropanoic acid and (S)-2-chloro-3-phenylpropanoic acid in eleven steps with a total yield of 13percent.Noteworthy is the excellent yield of the BOP-Cl mediated lactamization reaction of the linear precursor 17 leading to the 24-membered macrocycle.
- Scherkenbeck, Juergen,Plant, Andrew,Harder, Achim,Mencke, Norbert
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p. 8459 - 8470
(2007/10/02)
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- Synthesis of 3,4-Bridged Indoles by Photocyclisation Reactions. Part 1. Photocyclisation of Halogenoacetyl Tryptophan Derivatives
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Although irradiation of N-chloroacetyltryptophan results in a poor yield of photocyclisation to the indole 4-position due to competing cyclisation to C-2, the photocyclisation of (dichloroacetyl)tryptophan derivatives gives, after addition of a nucleophile in work-up, 7-substituted pyrrolobenzazocines in good yield and with trans-stereospecificity.N-(Trichloroacetyl)tryptophan derivatives also undergo photocyclisation to give 3,4-bridged indoles.The structures of the azocinoindoles 13, 21, 22 and 35, and the azepinoindole 15 were confirmed by X-ray crystallography.In one case the preparation of a cycloalkaindole was possible by the irradiation of the α-chloro amide of an indol-3-yl alkanoic acid.
- Beck, Anthony L.,Mascal, Mark,Moody, Christopher J.,Slawin, Alexandra M. Z.,Williams, David J.,Coates, William J.
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p. 797 - 812
(2007/10/02)
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- Enantiomeric Recognition of Organic Ammonium Salts by Chiral Dialkyl-, Dialkenyl-, and Tetramethyl-Substituted Pyridino-18-crown-6 and Tetramethyl-Substituted Bis-pyridino-18-crown-6 Ligands: Comparison of Temperature-Dependent 1H NMR and Empirical Force
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Six new chiral pyridino-18-crown-6 and one chiral bis-pyridino-18-crown-6 ligands have been prepared.The pyridino-crowns contain either two isopropyl, two isobutyl, two (S)-sec-butyl, two benzyl, two 3-butenyl, or four methyl substituents on chiral macror
- Bradshaw, Jerald S.,Huszthy, Peter,McDaniel, Christopher W.,Zhu, Cheng Y.,Dalley, N. Kent,et al.
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p. 3129 - 3137
(2007/10/02)
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- STEREOCONTROLLED SYNTHESIS OF D-α-HYDROXY CARBOXYLIC ACIDS FROM L-AMINO ACIDS
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Optically active D-α-hydroxy carboxylic acids are obtained from L-amino acids via L-α-halocarboxylic acids and their stereoselective reaction with cesium p-nitrobenzoate.
- Kunz, Horst,Lerchen, Hans-Georg
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p. 1873 - 1876
(2007/10/02)
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- Process for producing an α-halogeno-β-phenylpropionic acid
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A process for producing an α-halogeno-β-phenylpropionic acid represented by the general formula: STR1 where X is a halogen atom, which comprises hydrolyzing under heating a halogen-containing ethylbenzene derivative represented by the general formula: STR
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- Preparation of α-Bromo- and α-Chlorocarboxylic Acids from α-Amino Acids
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Diazotization of α-amino acids in 48:52 (w/w) hydrogen fluoride/pyridine along with excess of potassium halide results in the corresponding α-halocarboxylic acids in good to excellent yields (Table 1 and 2).
- Olah, George A.,Shih, Joseph,Prakash, G. K. Surya
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p. 1028 - 1030
(2007/10/02)
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- Direct Conversion of Arylamines to the Halides by Deamination with Thionitrite or Related Compounds and Anhydrous Copper(II) Halides
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Reactions of various arylamines with either t-butyl thionitrite, t-butyl thionitrate, or p-toluenesulfonyl nitrite in the presence of anhydrous copper(II) halides under mild conditions gave corresponding aryl halides in good yields.This reaction in the presence of such olefins as acrylonitrile, styrene, and acrylic acid gave the corresponding 2-aryl-1-haloethanes as the main products. t-Butyl thionitrite, t-butyl thionitrate, and p-toluenesulfonyl nitrite were found to be better deaminative reagents than alkyl nitrites or alkyl nitrates due to their weak sulfur-nitrogen bonds.
- Oae, Shigeru,Shinhama, Koichi,Kim, Yong Hae
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p. 1065 - 1069
(2007/10/02)
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