- Understanding the binding properties of phosphorylated glycoluril-derived molecular tweezers and selective nanomolar binding of natural polyamines in aqueous solution
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A modular synthetic platform for the construction of flexible glycoluril-derived molecular tweezers was developed. The binding properties of four exemplary supramolecular hosts obtained via this approach towards 16 organic amines were investigated by means of 1H NMR titration. In this work, we compare the Ka values obtained this way with those of three structurally related molecular tweezers and provide a computational approach towards an explanation of the observed behavior of those novel hosts. The results showcase that certain structural modifications lead to very potent and selective binders of natural polyamines, with observed binding of spermine below 10 nM. This journal is
- Heilmann, Michael,Knezevic, Melina,Piccini, Giovannimaria,Tiefenbacher, Konrad
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supporting information
p. 3628 - 3633
(2021/05/04)
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- Overriding Intrinsic Reactivity in Aliphatic C?H Oxidation: Preferential C3/C4 Oxidation of Aliphatic Ammonium Substrates
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The site-selective C?H oxidation of unactivated positions in aliphatic ammonium chains poses a tremendous synthetic challenge, for which a solution has not yet been found. Here, we report the preferential oxidation of the strongly deactivated C3/C4 positions of aliphatic ammonium substrates by employing a novel supramolecular catalyst. This chimeric catalyst was synthesized by linking the well-explored catalytic moiety Fe(pdp) to an alkyl ammonium binding molecular tweezer. The results highlight the vast potential of overriding the intrinsic reactivity in chemical reactions by guiding catalysis using supramolecular host structures that enable a precise orientation of the substrates.
- Heilmann, Michael,Knezevic, Melina,Piccini, Giovanni Maria,Tiefenbacher, Konrad
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supporting information
p. 12387 - 12391
(2020/07/04)
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- PREPARATION AND USES OF REACTIVE OXYGEN SPECIES SCAVENGER DERIVATIVES
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Compounds of Formula (I) a or (I) b: including certain quinone derivatives, and the corresponding pharmaceutical compositions, which may serve to modulate ferroptosis in a subject. Also disclosed herein are the preparations of these compounds and pharmaceutical compositions and their potential uses in the manufacture of a medicament in reducing reactive oxygen species (ROS) in a cell and for preventing, treating, ameliorating certain related disorder or a disease.
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Page/Page column 93-94
(2019/03/07)
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- Regioselective bromination of 1,4-dimethoxy-2,3-dimethylbenzene and conversion into sulfur-functionalised benzoquinones
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The NBS bromination of 1,4-dimethoxy-2,3-dimethylbenzene has been examined under a variety of conditions in both 1,1,1-trichloroethane and benzotrifluoride. Four different bromination products have been isolated including the previously unknown 1-bromo-4-
- Aitken, R. Alan,Jethwa, Siddharth J.,Richardson, Neville V.,Slawin, Alexandra M.Z.
-
supporting information
p. 1563 - 1566
(2018/03/29)
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- Microwave-assisted methylation of dihydroxybenzene derivatives with dimethyl carbonate
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Using a focused microwave reactor, methylation with dimethyl carbonate (DMC) of 1,2- and 1,4-dihydroxybenzene derivatives, found in the product spectrum of lignin depolymerisation, leads to the respective aromatic bis-methyl ethers with excellent isolated yields. Stoichiometric as well as catalytic amounts of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) are effective for the bis-methylation of these dihydroxybenzenes at relatively mild temperatures (160-190 °C). Conversion of resorcinol (1,3-dihydroxybenzene) under similar conditions leads to a mixture of 1,3-dimethoxybenzene and methyl 2,4-dimethoxybenzoate. The unusual reactivity of resorcinol's phenyl ring towards DMC can be explained by the synergic effect of its two strongly activating ortho/para directing groups.
- Lui, Matthew Y.,Lokare, Kapil S.,Hemming, Ellen,Stanley, Jessica N.G.,Perosa, Alvise,Selva, Maurizio,Masters, Anthony F.,Maschmeyer, Thomas
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p. 58443 - 58451
(2016/07/06)
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- Rh-Catalyzed Reactions of 1,4-Benzoquinones with Electrophiles: C-H Iodination, Bromination, and Phenylselenation
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Under Rh-catalyzed conditions, typically electrophilic 1,4-benzoquinones exhibit nucleophilic reactivity, such that exposure to appropriate electrophiles generates products of C-H iodination, bromination, and phenylselenation. This provides a mild and general method for direct halofunctionalization, and the first method that can achieve direct C-H phenylselenation of this compound class. The scope and limitations of the new protocols are outlined, and representative derivatizations are highlighted.
- Jardim, Guilherme A. M.,Bower, John F.,Da Silva Júnior, Eufranio N.
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supporting information
p. 4454 - 4457
(2016/09/28)
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- ALKYLATION OF PHENOLIC COMPOUNDS
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The invention relates to a process for O-alkyiation of a phenolic compound comprising at least two hydroxyl groups bonded to an aromatic hydrocarbon, the process comprising reacting the phenolic compound with an alkylating agent in the presence of a base, at a suitable reaction temperature and for a suitable time period, thereby alkylating the at least two hydroxy] groups. The invention also relates to O-alkylaled phenolic compounds produced by this process.
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Page/Page column 36
(2015/04/28)
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- PYRAZOLOPYRIDINE PYRAZOLOPYRIMIDINE AND RELATED COMPOUNDS
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In one aspect this invention relates generally to compounds of Formula: and sub-formulas thereof, or a tautomer of each thereof, a pharmaceutically acceptable salt of each thereof, or a pharmaceutically acceptable solvate of each of the foregoing, where X1, L1, L3, and R3 are described herein.
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-
Paragraph 0505; 0506
(2015/11/25)
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- Total synthesis of (R, R, R)-γ-tocopherol through cu-catalyzed asymmetric 1,2-addition
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Based on the asymmetric copper-catalyzed 1,2-addition of Grignard reagents to ketones, (R, R, R)-γ-tocopherol has been synthesized in 36% yield over 12 steps (longest linear sequence). The chiral center in the chroman ring was constructed with 73% ee by the 1,2-addition of a phytol-derived Grignard reagent to an a-bromo enone prepared from 2,3-dimethylquinone.
- Wu, Zhongtao,Harutyunyan, Syuzanna R.,Minnaard, Adriaan J.
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supporting information
p. 14250 - 14255
(2015/03/18)
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- Composition for treatment of pathogens that are resistant to tetracyclines
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The invention relates to compounds and pharmaceutical compositions useful in combination with tetracyclines in the treatment of bacterial infections caused by Gram-positive and Gram-negative pathogens, with particular efficacy in tetracycline resistant st
- -
-
Paragraph 0103-0104
(2014/08/19)
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- COMPOSITION FOR TREATMENT OF PATHOGENS THAT ARE RESISTANT TO TETRACYCLINES
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The invention relates to compounds and pharmaceutical compositions useful in combination with tetracyclines in the treatment of bacterial infections caused by Gram- positive and Gram-negative pathogens, with particular efficacy in tetracycline resistant s
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Page/Page column 30
(2014/08/19)
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- Synthesis of murrayaquinone A and analogues via ring-closing C-H arylation
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A compact synthesis of Murrayaquinone A is reported, based on sequential Buchwald-Hartwig amination/annulative C-H activation followed by oxidation of the intermediate carbazole. The methodology can be readily extended to other analogues with electron-rich quinone rings.
- Bedford, Robin B.,Bowen, John G.,Weeks, Amanda L.
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p. 4389 - 4394
(2013/06/26)
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- Enzymatic substrates derived from phenoxazinone and their use as developer in detection of microorganisms with peptidase activity
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Novel enzymatic substrates of the general formula below: reaction media containing the same and their use for detecting and/or identifying and/or quantifying microorganisms expressing at least one peptidase activity.
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Page/Page column 14-15
(2009/12/07)
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- Synthesis and testing of chromogenic phenoxazinone substrates for β-alanyl aminopeptidase
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Novel 7-N-(β-alanyl)aminophenoxazin-3-one salts 27a-d have been synthesized and tested as chromogenic substrates for β-alanyl aminopeptidase, which is present in Pseudomonas aeruginosa, the most common respiratory pathogen in patients with cystic fibrosis. The biological results show that 7-N-(β-alanyl)amino-1-pentylphenoxazin-3-one trifluoroacetate salt 27a is a chromogenic substrate for this bacterium, with a low degree of diffusion in nutrient media for growing bacterial cultures and a bright red colour, making it easily distinguishable from the agar background. This journal is The Royal Society of Chemistry.
- Zaytsev, Andrey V.,Anderson, Rosaleen J.,Bedernjak, Alexandre,Groundwater, Paul W.,Huang, Yongxue,Perry, John D.,Orenga, Sylvain,Roger-Dalbert, Celine,James, Arthur
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p. XX682-692
(2008/09/17)
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- Synthesis and cytotoxicity evaluation of some benzimidazole-4,7-diones as bioreductive anticancer agents
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New benzimidazole-4,7-diones substituted at 2-position were synthesized via a microwave-assisted reaction using 2-chloromethyl-1,5,6-trimethyl-1H-benzimidazole-4,7-dione 5b as a key intermediate compound. Their cytotoxicity has been evaluated on colon, br
- Gellis, Armand,Kovacic, Herve,Boufatah, Narimene,Vanelle, Patrice
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p. 1858 - 1864
(2008/12/22)
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- New Drug Delivery System for Crossing the Blood Brain Barrier
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New ubiquinol analogs are disclosed, as well as methods of using these compounds to deliver drug moieties to the body.
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Page/Page column 28
(2008/06/13)
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- Vitamin E metabolites: Synthesis of [D2]- and [D 3]-γ-CEHC
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Deuterated analogues of α- and γ-CEHC, main urinary and plasma metabolites of vitamin E, can be traced and accurately determined quantitatively by MS in complex matrices. In that regard, here we report the first synthesis of rac-[D3]-γ-CEHC together with a simple route to 7a,8a-[D2]-γ-CEHC through the set up of efficient procedures for the preparation of the corresponding deuterated hydroquinone building blocks. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Mazzini, Francesco,Galli, Francesco,Salvadori, Piero
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p. 5588 - 5593
(2008/02/04)
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- Two-photon photochemical generation of reactive enediyne
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p-Quinoid cyclopropenone-containing enediyne precursor (1) has been synthesized by monocyclopropanation of one of the triple bonds in p-dimethoxy-substituted 3,4-benzocyclodeca-1,5-diyne followed by oxidative demethylation. Cyclopropenone 1 is stable up t
- Poloukhtine, Andrei,Popik, Vladimir V.
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p. 7417 - 7421
(2007/10/03)
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- Treatment of mitochondrial diseases
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The invention relates the method of treatment or amelioration of mitochondrial disorders such as Alzheimer's disease, Parkinson's disease, Friedreich's ataxia (FRDA), cerebellar ataxias, Leber's hereditary optic neuropathy (LHON), mitochondrial myopathy,
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- Synthesis of chiral chromans by the Pd-catalyzed asymmetric allylic alkylation (AAA): Scope, mechanism, and applications
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The Pd-catalyzed asymmetric allylic alkylation (AAA) of phenol allyl carbonates serves as an efficient strategy to construct the allylic C-O bond allowing access to chiral chromans in up to 98% ee. The effect of pH and the influence of olefin geometry, as well as substitution pattern on the ee and the absolute configuration of the chiral chromans were explored in detail. These observations suggest a mechanism involving the cyclization of the more reactive π-allyl palladium diastereomeric intermediate as the enantiodiscriminating step (Curtin-Hammett conditions). This methodology led to the enantioselective synthesis of the vitamin E core, the first enantioselective total synthesis of (+)-clusifoliol and (-)-siccanin, and the synthesis of an advanced intermediate toward (+)-rhododaurichromanic acid A.
- Trost, Barry M.,Shen, Hong C.,Dong, Li,Surivet, Jean-Philippe,Sylvain, Catherine
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p. 11966 - 11983
(2007/10/03)
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- Efficient microwave-assisted synthesis of new sulfonylbenzimidazole-4,7- diones: Heterocyclic quinones with potential antitumor activity
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New benzimidazoloquinones substituted at 2-position by a sulfonyl group have been synthesized via a final microwave assisted step using 2-chloromethyl-1,5,6-trimethylbenzimidazole-4,7-dione 7 as starting material.
- Boufatah, Narimène,Gellis, Armand,Maldonado, José,Vanelle, Patrice
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p. 9131 - 9137
(2007/10/03)
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- New Benzo[b]xanthones from Diels-Alder Reactions of Chromone-3- carboxaldehydes with ortho-Benzoquinodimethanes
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New benzo[b]xanthone derivatives, having substituents in the A and D rings, were prepared from cycloaddition reactions of chromone-3-carboxaldehydes with ortho-benzoquinodimethanes, generated in situ from 1,3-dihydrobenzo[c]thiophene 2,2-dioxide, followed
- Sandulache, Angela,Silva, Artur M. S.,Cavaleiro, Jose A. S.
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p. 551 - 563
(2007/10/03)
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- Synthesis and characterization of a 5,6-dibromobenzoquinone-phenyl maleimide adduct
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A six-step synthesis was used to prepare a 5,6-dibromobenzoquinone-phenyl maleimide adduct (8). The structure of (8) and four of the intermediates are described. This dibromide is used as the starting material for the synthesis of 2-amino-1,2,3-triazoles
- Mendez-Rojas, Miguel A.,Ejsmont, Krzysztof,Watson, William H.
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p. 177 - 184
(2007/10/03)
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- New synthetic route to [bis-1,2-(aminomethyl)benzene]dichloroplatinum(II) complexes, screening for cytotoxic activity in cisplatin-sensitive and resistant human cancer cell lines, and reaction with glutathione
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A new synthetic route to [bis-1,2-(aminomethyl)benzene]dichloroplatinum(II) complexes is described. o-Xylene and the 4-methoxy substituted derivative were used as starting points for the synthesis: benzylic bromination with N-bromosuccinamide /benzoylperoxide followed by the substitution of the benzyl bromides for azide and finally a catalytic hydrogenation with Pd/C of the diazides gave the desired diamines ligands. An attempt to synthesize the 4,6-dimethoxy derivative was unsuccessful due to the bromination of the aromatic ring. The diamines were complexed with K2PtCl4 to give the target Pt(II) complexes: [1,2-bis(aminomethyl)benzene]dichloroplatinum(II) (4a) and [1,2-bis(aminomethyl)-4-methoxy-benzene]dichloroplatinum(II) (4b). Screening for cytotoxic activity was done in comparison to cisplatin in a panel of eight human cancer cell lines; in all cases, the 4-methoxy derivative 4b was less active than the unsubstituted analog, 4a. In four cell lines 4a was as potent as cisplatin, while in the other four lines cisplatin was considerably more potent then 4a. The 5637 bladder cancer cell line was made 4-5 fold resistant to either cisplatin or [d,l-trans-1,2-diaminocyclohexane]dichloroplatinum(II); 4a showed some cross resistance (2-3 fold) to both resistant cell lines. The reactivity of 4a towards substitutions with glutathione (GSH), a biological thiol involved in intrinsic and acquired resistance to Pt-complexes, was measured by a RP-HPLC method. It was found that the second-order rate constant for the reaction of 4a with GSH was similar to that that reported for CDDP, indicating that reactivity towards GSH does not explain the different levels of cross resistance.
- Rinke,Gruenert,Bednarski
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p. 763 - 769
(2007/10/03)
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- Electro-organic reactions. Part 54: Quinodimethane chemistry; Part 2 - Electrogeneration and reactivity of o-quinodimethanes
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The electrochemical generation and characterisation of a variety of o-quinodimethanes (o-QDMs) are described together with the outcome of preparative experiments in which they are key intermediates. The quinodimethanes are conveniently formed, in DMF, by both direct and redox-catalysed electroreduction of 1,2-bis(halomethyl)arenes. Their predominant reaction is polymerisation to poly(o-xylylene) (o-PX) polymers. In the presence of dienophiles the electrogenerated o-QDMs may undergo efficient cycloaddition reaction and distinctions between the possible mechanisms have been attempted on the basis of voltammetric, preparative and stereochemical experiments. Contrary to the precedent of the corresponding methyl ester, diphenyl maleate radical-anion isomerises only slowly to the fumarate radical-anion, yet co-electrolysis of 2,3-bis(bromomethyl)-1,4-dimethoxybenzene and diphenyl maleate or diphenyl fumarate gives exclusively the corresponding trans-adduct. Co-electrolysis of dimethyl maleate with either 1,2-bis(bromomethyl)benzene (more easily reduced) or 2,3-bis(bromomethyl)-1,4-dimethoxybenzene (less easily reduced) gave only o-PX polymer. The results are rationalised in terms of a double nucleophilic substitution mechanism where electron transfer between dienophile radical-anion and dihalide is relatively slow. Where electron transfer from maleate or fumarate radical-anions is likely to be fast o-quinodimethanes are formed by redox-catalysis and they polymerise rather than undergo Diels-Alder reaction. Dimerisation of the dienophile radical-anions, with k2 = 104 to 105 M-1 s-1, does not apparently compete with nucleophilic substitution or, where relevant, electron transfer.
- Utley, James H.P.,Ramesh, Shalini,Salvatella, Xavier,Szunerits, Sabine,Motevalli, Majid,Nielsen, Merete F.
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p. 153 - 163
(2007/10/03)
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- Synthesis of 2,3-dialkylquinones by Bis-SRN1 methodology
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Three series of complex dialkylquinones were prepared by reacting bis(chloromethyl)quinones with simple and more complex nitronate anions under electron transfer reaction conditions.
- Terme,Maldonado,Crozet,Vanelle
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p. 3877 - 3883
(2007/10/03)
-
- A convergent approach to coenzyme Q
-
Syntheses of coenzyme Q3-8 are described, as well as related systems such as plastoquinone-5. Preparation of the higher homologues of the ubiquinones relies on two new conjunctive reagents, or "linchpins", each of which ultimately corresponds to two or three prenyl units. These allow for attachment of a polyprenyl halide at one end, followed by a Ni(0)-catalyzed cross-coupling at the other terminus with a chloromethylated p-quinone.
- Lipshutz, Bruce H.,Bulow, Gerd,Fernandez-Lazaro, Fernando,Kim, Sung-Kyu,Lowe, Richard,Mollard, Paul,Stevens, Kirk L.
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p. 11664 - 11673
(2007/10/03)
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- Selective nitration versus oxidative dealkylation of hydroquinone ethers with nitrogen dioxide
-
Various alkyl-substituted p-dialkoxybenzenes (ArH) react readily with nitrogen dioxide (NO2) in dichloromethane solution via either nitration (ArNO2) or oxidative dealkylation to quinones (Q). Spectral transients indicate that these coupled processes proceed from the dialkoxybenzene radical cation (ArH+) formed as the common reactive intermediate from electron-transfer in the disproportionated precursor [ArH, NO+]NO3-. In fast subsequent steps, ArH+ undergoes homolytic coupling with NO2 (which leads to aromatic nitration) and nucleophilic attack of NO3- (which results in oxidative dealkylation). As such, the competition between nitration and oxidative dealkylation is effectively modulated by solvent polarity and added nitrate.
- Rathore,Bosch,Kochi
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p. 6727 - 6758
(2007/10/02)
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- Efficient synthesis of 5,8-disubstituted-1,4-dihydrobenzoxathiin-3-oxides and their isomeric structures, 4,7-disubstituted-1,3-dihydrobenzo[b] thiophene-2,2-dioxides
-
Functionalized dihydrobenzoxathiin oxides and dihydrobenzothiophene-2,2-dioxides 11-18 have been prepared via trapping of sulfur dioxide under photolytic or ground state conditions.
- Attardo, Giorgio,Wang, Wuyi,Kraus, Jean-Louis,Belleau, Bernard
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p. 4743 - 4746
(2007/10/02)
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- Synthesis of a New Rigid Quinone-Amino Acid and Diels-Alder Extension to Higher Quinones
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Electron deficient cyclic α-amino acid derivatives bearing 1,4-benzoquinone and 1,4-anthraquinone side chains were synthesized by an novel route.The common precursor, 2-amino-4,7-dimethoxy-indan-2-carboxylic acid, may be incorporated into a peptide prior
- Kotha, Sambasivarao,Kuki, Atsuo
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p. 299 - 302
(2007/10/02)
-