- Me3SI-promoted chemoselective deacetylation: a general and mild protocol
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A Me3SI-mediated simple and efficient protocol for the chemoselective deprotection of acetyl groups has been developedviaemploying KMnO4as an additive. This chemoselective deacetylation is amenable to a wide range of substrates, tolerating diverse and sensitive functional groups in carbohydrates, amino acids, natural products, heterocycles, and general scaffolds. The protocol is attractive because it uses an environmentally benign reagent system to perform quantitative and clean transformations under ambient conditions.
- Gurawa, Aakanksha,Kashyap, Sudhir,Kumar, Manoj
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p. 19310 - 19315
(2021/06/03)
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- 15-PGDH INHIBITOR
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[Problem] To provide a compound having a 15-PGDH inhibitory effect. [Solution] A compound represented by general formula (1) or a pharmacologically acceptable salt thereof.
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Paragraph 0330-0331
(2021/12/23)
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- SUBSTITUTED CHROMEN-4-ONE FOR THE TREATMENT AND PROPHYLAXIS OF HEPATITIS B VIRUS INFECTION
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The present invention provides novel compounds having the general formula: (I) wherein R1 to R10, Gi, G2 and m are as described herein, compositions including the impounds and methods of using the compounds for the treatment of hepatitis B.
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Page/Page column 26-27
(2020/07/31)
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- Site-Selective C?H Oxygenation via Aryl Sulfonium Salts
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Herein, we report a two-step process forming arene C?O bonds in excellent site-selectivity at a late-stage. The C?O bond formation is achieved by selective introduction of a thianthrenium group, which is then converted into C?O bonds using photoredox chemistry. Electron-rich, -poor and -neutral arenes as well as complex drug-like small molecules are successfully transformed into both phenols and various ethers. The sequence differs conceptually from all previous arene oxygenation reactions in that oxygen functionality can be incorporated into complex small molecules at a late stage site-selectively, which has not been shown via aryl halides.
- Sang, Ruocheng,Korkis, Stamatis E.,Su, Wanqi,Ye, Fei,Engl, Pascal S.,Berger, Florian,Ritter, Tobias
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supporting information
p. 16161 - 16166
(2019/11/03)
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- Structure optimization of a new class of PPARγ antagonists
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Peroxisome proliferator-activated receptor gamma (PPARγ) modulators have found wide application for the treatment of cancers, metabolic disorders and inflammatory diseases. Contrary to PPARγ agonists, PPARγ antagonists have been much less studied and alth
- Hernandez-Olmos, Victor,Knape, Tilo,Heering, Jan,von Knethen, Andreas,Kilu, Whitney,Kaiser, Astrid,Wurglics, Mario,Helmst?dter, Moritz,Merk, Daniel,Schubert-Zsilavecz, Manfred,Parnham, Michael J.,Steinhilber, Dieter,Proschak, Ewgenij
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supporting information
(2019/09/30)
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- Synthesis of Polysubstituted 3-Methylisoquinolines through the 6π-Electron Cyclization/Elimination of 1-Azatrienes derived from 1,1-Dimethylhydrazine
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A convenient one pot microwave-assisted 6π-electron cyclization/aromatization approach toward 3-methylisoquinolines is reported. The starting 1-azatriene derivatives were prepared in situ by reaction of 2-propenylbenzaldehydes with 1,1-dimethylhydrazine, which exhibited superior performance when compared with other hydrazine derivatives. Minor amounts of the related 3,4-dihydro isoquinolines were formed concomitantly with the isoquinolines, and a mechanism for their generation was proposed. The reaction conditions were optimized, and its scope and limitations were explored. In general, the transformation proceeded in moderate to good yields.
- Vargas, Didier F.,Larghi, Enrique L.,Kaufman, Teodoro S.
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supporting information
p. 5605 - 5614
(2018/10/09)
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- Synthesis and identification of metabolite biomarkers of 25C-NBOMe and 25I-NBOMe
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Synthetic routes have been developed for synthesis of potential metabolites of 25C-NBOMe and 25I-NBOMe. Nine potential metabolites have been synthesized, among which compounds 8 and 20a could be used as metabolite biomarkers of 25C-NBOMe and 20b of 25I-NB
- Wu, Xiongyu,Eriksson, Caroline,Wohlfarth, Ariane,Wallgren, Jakob,Kronstrand, Robert,Josefsson, Martin,Dahlén, Johan,Konradsson, Peter
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p. 6393 - 6400
(2017/10/16)
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- Hydrogen-Bonding-Induced Fluorescence: Water-Soluble and Polarity-Independent Solvatochromic Fluorophores
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Fluorophores with emission wavelengths that shift depending on their hydrogen-bonding microenvironment in water would be fascinating tools for the study of biological events. Herein we describe the design and synthesis of a series of water-soluble solvatochromic fluorophores, 2,5-bis(oligoethylene glycol)oxybenzaldehydes (8-11) and 2,5-bis(oligoethylene glycol)oxy-1,4-dibenzaldehydes (14-17), based on a push-pull strategy. Unlike typical examples in this class of fluorophores, the fluorescence properties of these compounds are independent of solvent polarity and become fluorescent upon intermolecular hydrogen-bonding, exhibiting high quantum yields (up to φ = 0.55) and large Stokes shifts (up to 134 nm). Furthermore, their emission wavelengths change depending on their hydrogen-bonding environment. The described fluorophores provide a starting point for unprecedented applications in the fields of chemical biology and medicinal chemistry.
- Okada, Yohei,Sugai, Masae,Chiba, Kazuhiro
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p. 10922 - 10929
(2016/11/29)
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- Studies on synthesis of quinonylidene Hoveyda-type complexes
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In a quest of redox-switchable metathesis catalysts we attempted synthesis of ruthenium quinonylidene complexes using two synthetic pathways. First, Hoveyda-type complexes bearing chelating benzylidene and naphthylidene ligands substituted with two alkoxy/hydroxy groups were synthesized and characterized. The catalysts were tested in model ring-closing metathesis reactions, and displayed interesting correlations between structure and catalytic activity. Unfortunately, numerous attempts at oxidation of the complexes to derivatives of benzo- and naphthoquinone were unsuccessful. However, the second approach, using exchange reaction of ruthenium precursor with vinylquinone ligand, gave a transient unstable product observed with 1H NMR. The experimental data suggest that conjugation of electron-deficient quinones to the ruthenium centre results in intrinsically unstable species, which undergo secondary reactions under ambient conditions.
- Grudzień, Krzysztof,Barbasiewicz, Micha?
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p. 322 - 327
(2015/04/27)
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- SUBSTITUTED BENZALDEHYDE COMPOUNDS AND METHODS FOR THEIR USE IN INCREASING TISSUE OXYGENATION
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Provided are substituted benzaldehydes and derivatives thereof that act as allosteric modulators of hemoglobin, methods and intermediates for their preparation, pharmaceutical compositions comprising the modulators, and methods for their use in treating disorders mediate by hemoglobin and disorders that would benefit from increased tissue oxygenation.
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Paragraph 0193
(2013/07/19)
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- Proton-electron transfer pathways in the reactions of peroxyl and dpph ? radicals with hydrogen-bonded phenols
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The kinetics of the reaction of peroxyl and dpph? radicals with phenols H-bonded to N-bases have been studied for the first time. Electron-transfer processes are observed in MeCN but only with the dpph radical.
- Amorati, Riccardo,Menichetti, Stefano,Viglianisi, Caterina,Foti, Mario C.
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supporting information
p. 11904 - 11906
(2013/01/16)
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- General copper-catalyzed transformations of functional groups from arylboronic acids in water
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A simple and general copper-catalyzed method has been developed for transformations of various functional groups (i I, i N3, i SO2R, i OH, i NH2, and i NO 2) on aromatic rings from arylboronic acids in water under air. The protocol uses cheap and readily available inorganic salts (KI, NaN3, NaSO2R, NaOH, NaNO2) and aqueous ammonia as the functional-group sources, simple Cu2O/NH3 as the catalyst system, environmentally friendly water as the solvent, and oxygen in air as the oxidant. Importantly, the copper catalyst system in water was recyclable. This study should provide a useful strategy for interconversions of the functional groups on aromatic rings.
- Yang, Haijun,Li, Yong,Jiang, Min,Wang, Junmei,Fu, Hua
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experimental part
p. 5652 - 5660
(2011/06/23)
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- The selective reaction of aryl halides with KOH: Synthesis of phenols, aromatic ethers, and benzofurans
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The direct and selective synthesis of phenols from aryl/heteroaryl halides and KOH has been achieved through the use of highly active monophosphine-based catalysts derived from Pd2dba3 and ligands L1 or L2 and the biphasic solvent system 1,4-dioxane/H2O. We have also demonstrated a one-pot method of phenol formation/alkylation for the preparation of alkyl aryl ethers from aryl halides. In many instances, this protocol overcomes limitations in existing Pd-catalyzed coupling reactions of aliphatic alcohols with aryl halides. Finally, we demonstrate that substituted benzofurans can be prepared efficiently via a Pd-catalyzed phenol formation/cyclization protocol starting from 2-chloroaryl alkynes. Copyright
- Anderson, Kevin W.,Ikawa, Takashi,Tundel, Rachel E.,Buchwald, Stephen L.
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p. 10694 - 10695
(2007/10/03)
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- Inhibition of Pneumocystis carinii, Toxoplasma gondii, and Mycobacterium avium dihydrofolate reductases by 2,4-diamino-5-[2-methoxy-5-(ω-carboxyalkyloxy)benzyl]pyrimidines: Marked improvement in potency relative to trimethoprim and species selectivity relative to piritrexim
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A series of previously undescribed 2,4-diamino-5-[2-methoxy-5-alkoxybenzyl]pyrimidines (3a-e) and 2,4-diamino-5-[2-methoxy-5-(ω-carboxyalkyloxy)benzyl]pyrimidines (3f-k) with up to eight CH2 groups in the alkoxy or ω-carboxyalkyloxy side chain were synthesized and tested for the ability to inhibit partially purified dihydrofolate reductase (DHFR) from Pneumocystis carinii (Pc), Toxoplasma gondii (Tg), Mycobacterium avium (Ma), and rat liver in comparison with two standard inhibitors, trimethoprim (1) and piritrexim (2). The latter drug is known to be extremely potent but shows a marked preference for binding to mammalian DHFR, whereas the former is very selective for the parasite enzymes but is a much weaker inhibitor. The underlying strategy for the synthesis of compounds 3a-k was that a hybrid structure embodying some features of both 1 and 2 might possess a more favorable combination of potency and selectivity than either parent drug. The choice of analogues 3f-k was based on the idea that the acidic ω-carboxyl group might interact preferentially with a basic center in the active site of DHFR from any of the parasite species relative to the active site of mammalian DHFR. In addition, the ω-carboxyl group was expected to improve water solubility relative to 1 or 2. In standardized spectrophotometric assays with dihydrofolate as the substrate and NADPH as the cofactor, 2,4-diamino-5-[(2-methoxy-4-carboxybutyloxy)benzyl]pyrimidine (3g) inhibited Pc DHFR with an IC50 of 0.049 μM and rat DHFR with IC50 of 3.9 μM. Its potency against Pc DHFR was 140-fold greater than that of 1 and close to that of 2, and its selectivity index, defined as the ratio IC50(rat liver)/IC50(P. carinii), was 8-fold higher than that of 1 and > 104fold higher than that of 2. Although it was less potent and less selective against Tg than Pc DHFR, it was very potent as well as highly selective against Ma DHFR, with an IC50 of 0.0058 μM and an IC50(rat liver)/IC50(M. avium) ratio of > 600. Because of this favorable combination of potency and selectivity relative to 1 and 2, compound 3g may be viewed as a promising lead in the search for new antifolates with potential clinical activity against P. carinii and other opportunistic pathogens in patients with AIDS.
- Rosowsky,Forsch,Queener
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p. 233 - 241
(2007/10/03)
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- Selective Formylation of Diphenols
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An improved procedure for the regioselective formylation of ortho- and para-diphenols is described.
- Scarpati, Maria Luisa,Bianco, Armandodoriano,Mascitelli, Livia,Passacantilli, Pietro
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p. 2565 - 2572
(2007/10/02)
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