- Fluspirilene Analogs Activate the 20S Proteasome and Overcome Proteasome Impairment by Intrinsically Disordered Protein Oligomers
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Oligomerization of aggregation-prone intrinsically disordered proteins (IDPs), such as α-synuclein, amyloid β, and tau, has been shown to be associated with the pathogenesis of several neurodegenerative diseases, including Parkinson's and Alzheimer's disease. The proteasome is charged with regulating cellular levels of IDPs, but this degradation pathway can become dysregulated leading to their accumulation and subsequent aggregation. Although the pathogenesis of these neurodegenerative diseases is still under intense investigation, it has been shown that the oligomeric forms of IDPs, including α-synuclein and amyloid β, can impair proteasome function. This leads to additional accumulation of the IDPs, further promoting disease progression. Herein, we report the use of small molecule activators of the 20S subcomplex of the proteasome to restore impaired 20S proteasome activity and prevent IDP accumulation and oligomerization. We found that fluspirilene and its new synthetic analog (16) show strong 20S proteasome enhancement (doubling 20S proteolytic activity at μ2 μM, with maximum fold enhancement of μ1000%), overcome impaired proteasome function, and prevent the accumulation of pathogenic IDPs. These findings provide support for the use of 20S enhancers as a possible therapeutic strategy to combat neurodegenerative diseases.
- Fiolek, Taylor J.,Keel, Katarina L.,Tepe, Jetze J.
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p. 1438 - 1448
(2021/05/04)
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- Remote C(sp3)?H Arylation and Vinylation of N-Alkoxypyridinium Salts to δ-Aryl and δ-Vinyl Alcohols
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The reaction of readily available and bench-stable N-alkoxypyridinium salts with arylboronic and vinylboronic acids afforded δ-aryl and δ-vinyl alcohols, respectively, in the presence of fac-Ir(ppy)3 and Cu(OTf)2 dual catalysts. The reaction takes place through a domino process involving the reductive generation of alkoxyl radicals, 1,5-hydrogen atom transfer (1,5-HAT) and the copper-catalyzed cross-coupling reaction of the resulting translocated carbon radicals with boronic acids. Complementary to the Minisci reaction, this method allows for the arylation of nucleophilic alkyl radicals with both electron-rich and electron-poor arenes under mild reaction conditions.
- Bao, Xu,Wang, Qian,Zhu, Jieping
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supporting information
(2019/08/21)
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- Heterocyclization involving benzylic C(sp3)-H functionalization enabled by visible light photoredox catalysis
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A general and efficient method for heterocyclization involving benzylic C(sp3)-H functionalization enabled by visible light photoredox catalysis to access a wide range of structurally diverse oxygen as well as nitrogen heterocycles up to a gram scale is reported. The potential application of this new methodology is demonstrated by the total synthesis of (-)-codonopsinine and (+)-centrolobine. Herein it is proposed that selectfluor, unlike a fluorinating reagent, acts as an oxidative quencher and a hydrogen radical acceptor.
- Pandey, Ganesh,Laha, Ramkrishna,Mondal, Pradip Kumar
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p. 9689 - 9692
(2019/08/15)
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- New 1,3-dioxolane and 1,3-dioxane derivatives as effective modulators to overcome multidrug resistance
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Multidrug resistance (MDR) to antitumor agents represents a major obstacle to a successful chemotherapy of cancer. Overexpression of P-glycoprotein (p-gp) seems to be the major factor responsible for MDR. A large number of chemically unrelated compounds are known to interact with p-gp resulting in a decreasing resistance. In our efforts related to structure-activity studies of new potential MDR reversal agents we synthesized a series of compounds that differ in the aromatic core structure, the linker, and the basic moiety. For our search of new aromatic core structures we synthesized novel 2,2-diphenyl-1,3-dioxolane, 2,2- diphenyl-1,3-dioxane, and 4,5-diphenyl-1,3-dioxolane derivatives. A range of lipophilic linker structures and protonable basic moieties were synthesized and investigated to optimize the structure of the potential MDR-modulators. The compounds were tested in vitro using human Caco-2 cells. Both the cytotoxicity of the synthons and their ability to resensitize the cells were determined with a MTT assay. The results show that at low concentration various substances reverse tumor cell MDR. Some of the new structures show better effects than established modulators like trifluoperazine.
- Schmidt, Matthias,Ungvari, Johannes,Gloede, Julia,Dobner, Bodo,Langner, Andreas
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p. 2283 - 2297
(2007/10/03)
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- SIP3 RECEPTOR ANTAGONIST
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PROBLEM TO BE SOLVED: To obtain a compound having selective SIP3 receptor antagonism and a medicine containing the same. SOLUTION: The medicine comprises an aminopropionic acid derivative represented by general formula (1) (R1 is a hydrogen atom or a lower alkyl group; R2 is formula A; A is CO or CH2; E is an oxygen atom or an NR4; R3 is a lower alkyl group or formula B; G is CH, a nitrogen atom or a phosphorus atom; J is an oxygen atom or a sulfur atom; R4 is a hydrogen atom or a lower alkyl group; R5, R6 and R7 are each the same or different and a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group or a haloalkyl group; m is an integer of 1-8; n is an integer of 1-5) or its pharmaceutically permissible salt as an active ingredient.
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Page/Page column 22
(2010/02/14)
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- Dihydropyridine derivatives
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Compounds having a selective N-type calcium channel antagonistic activity are provided. Dihydropyridine derivatives represented by the following formula: analogs thereof and pharmaceutically acceptable salts thereof have an activity of selectively inhibiting the action of N-type calcium channel, and they are used as therapeutic agents for various diseases relating to N-type calcium channel.
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- DIHYDROPYRIDINE DERIVATIVE
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Compounds having a selective N-type calcium channel antagonistic activity are provided. Dihydropyridine derivatives represented by the following formula: analogs thereof and pharmaceutically acceptable salts thereof have an activity of selectively inhibiting the action of N-type calcium channel, and they are used as therapeutic agents for various diseases relating to N-type calcium channel.
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- Discovery of novel non-peptide CCR1 receptor antagonists
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Ligands for the CCR1 receptor (MIP-1α and RANTES) have been implicated in a number of chronic inflammatory diseases, most notably multiple sclerosis and rheumatoid arthritis. Because these ligands share a common receptor, CCR1, we sought to discover antagonists for this receptor as an approach to treating these disorders. A novel series of 4-hydroxypiperidines has been discovered by high throughput screening (HTS) which potently inhibits the binding of MIP-1α and RANTES to the recombinant human CCR1 chemokine receptor. The structure-activity relationships of various segments of this template are described as the initial HTS lead 1 was optimized synthetically to the highly potent receptor antagonist 6s. This compound has been shown to have at least 200-fold selectivity for inhibition of CCR1 over other human 7- TM receptors, including other chemokine receptors. In addition, data obtained from in vitro functional assays demonstrate the functional antagonism of compound 6s and structurally related analogues against the CCR1 receptor in a concentration dependent manner. The discovery and optimization of potent and selective CCR1 receptor antagonists represented by compound 6s potentially represent a novel approach to the treatment of chronic inflammatory diseases.
- Ng, Howard P.,Karen, May,Bauman, John G.,Ghannam, Ameen,Islam, Imadul,Liang, Meina,Horuk, Richard,Hesselgesser, Joseph,Snider, R. Michael,Perez, H. Daniel,Morrissey, Michael M.
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p. 4680 - 4694
(2007/10/03)
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- SUBSTITUTED QUINOLINES AND ISOQUINOLINES AS CALCIUM CHANNEL BLOCKERS, THEIR PREPARATION AND THE USE THEREOF
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The present invention relates to novel substituted quinolines and isoquinolines and derivatives thereof useful in the treatment of neurological disorders. Methods of preparing the compounds, intermediates useful in the preparation and pharmaceutical compositions containing the compounds are also included. The compounds are useful in treating pain, cerebral ischemia, and other cerebrovascular disorders.
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- Method of preparing optically active homo-beta-amino acids
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The present invention is directed to synthesis of homo-β-amino acids of an optical purity sufficient to exhibit optical activity wherein Curtius rearrangement of 3-mono-substituted succinate acid half ester of an optical purity sufficient to exhibit optical activity is affected and the incipient isocyanate is trapped with a primary or secondary alcohol. The resulting carbamate-protected homo-β-amino esters are then saponified to produce the corresponding carbamate-protected homo-β-amino acids which are deprotected to yield homo-β-amino acids of an optical purity sufficient to exhibit optical activity.
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- GABA-uptake inhibitors: Construction of a general pharmacophore model and successful prediction of a new representative
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A model for the pharmacophore of GABA-uptake inhibitors was established using published structure-activity data and molecular modeling. The model accounted for the activities of different classes of GABA-uptake inhibitors. Analogues of guvacine substituted at position 6 were synthesized in order to confirm the model. 6-(3,3-Diphenylpropyl)guvacine (30f), which fit well with the pharmacophore, had an in vitro IC50 of 0.1 μM. This value is as good as those of the best GABA-uptake inhibitors known today.
- N'Goka,Schlewer,Linget,Chambon,Wermuth
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p. 2547 - 2557
(2007/10/02)
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- Carbanion Rearrangements by Intramolecular 1,ω Proton Shifts, IV. The Reaction of ω,ω-Diphenylalkyllithium Compounds: Proof for an Intramolecular Transmetallation Reaction by Crossover Experiments Using Isotopic Labelled Starting Material
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3,3-Diphenylpropyllithium (2) and 2-(9-fluorenyl)ethyllithium (43) do not show a 1,3 proton shift but splitt off ethylene.On the other hand 4,4-diphenylbutyllithium (19) in diethyl ether can be forced to rearrange to 1,1-diphenylbutyllithium (18) by the addition of THF.The half reaction time for this 1,4 proton shift was found to be about 4 minutes.Proof for the intramolecular character of this transmetallation reaction was obtained by crossover experiments with specifically deuterated starting material.The 1,5 proton shift with 5,5-diphenylpentyllithium (12) occurs considerably slower than the 1,4 shift with 4,4-diphenylbutyllithium (19).The rearrangement also takes place in pure diethyl ether although with a half reaction time of about 2 days.Only 3-(9-fluorenyl)propyllithium (41) in diethyl ether spontaneously shows rearrangement already at -30 deg C, whereby 9-propyl-9-fluorenyllithium (42) is formed by a 1,4 proton shift.A 1,ω phenyl migration according to Grovenstein-Zimmerman in no case could be observed.
- Maercker, Adalbert,Passlack, Michael
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p. 710 - 723
(2007/10/02)
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- Possible Antihypertensive Agents: Syntheses of N-Aralkyl-β-substituted Phenylethylamines and N-Alkyl/acyl-6,7-dimethoxy-1--1,2,3,4-tetrahydroisoquinolines
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Syntheses of a number of N-arylalkyl-β-phenylethylamines and N-alkyl/acyl-6,7-dimethoxy-1--1,2,3,4-tetrahydroisoquinolines along with the results of antihypertensive screening in experimental animals have been described.
- Kansal, V. K.,Bhaduri, A. P.
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p. 885 - 890
(2007/10/02)
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- Acylation of Alcohols by Fatty Acid Esters in Presence of Lithium Aluminium Hydride
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A novel acylation of alcohols by fatty acid esters in the presence of lithium aluminium hydride is reported.A plausible mechanism of this acylation through the formation of a lithium aluminium tetraalkoxide complex has been suggested.
- Kumar, Shiv,Kansal, V. K.,Prashad, Mahavir,Bhaduri, A. P.
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p. 856 - 858
(2007/10/02)
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