2051-97-0Relevant academic research and scientific papers
Synthesis of a poly(ethylene glycol)-supported tetrakis ammonium salt: A recyclable phase-transfer catalyst of improved catalytic efficiency
Benaglia, Maurizio,Cinquini, Mauro,Cozzi, Franco,Tocco, Graziella
, p. 3391 - 3393 (2002)
The immobilization of four quaternary ammonium groups on a poly(ethylene glycol) support provided an efficient and recyclable phase-transfer catalyst.
Discovery of allosteric and selective inhibitors of inorganic pyrophosphatase from mycobacterium tuberculosis
Pang, Allan H.,Garzan, Atefeh,Larsen, Martha J.,McQuade, Thomas J.,Garneau-Tsodikova, Sylvie,Tsodikov, Oleg V.
, p. 3084 - 3092 (2016)
Inorganic pyrophosphatase (PPiase) is an essential enzyme that hydrolyzes inorganic pyrophosphate (PPi), driving numerous metabolic processes. We report a discovery of an allosteric inhibitor (2,4-bis(aziridin-1-yl)-6-(1-phenylpyrrol-2-yl)-s-triazine) of bacterial PPiases. Analogues of this lead compound were synthesized to target specifically Mycobacterium tuberculosis (Mtb) PPiase (MtPPiase). The best analogue (compound 16) with a Ki of 11 μM for MtPPiase is a species-specific inhibitor. Crystal structures of MtPPiase in complex with the lead compound and one of its analogues (compound 6) demonstrate that the inhibitors bind in a nonconserved interface between monomers of the hexameric MtPPiase in a yet unprecedented pairwise manner, while the remote conserved active site of the enzyme is occupied by a bound PPi substrate. Consistent with the structural studies, the kinetic analysis of the most potent inhibitor has indicated that it functions uncompetitively, by binding to the enzyme-substrate complex. The inhibitors appear to allosterically lock the active site in a closed state causing its dysfunctionalization and blocking the hydrolysis. These inhibitors are the first examples of allosteric, species-selective inhibitors of PPiases, serving as a proof-of-principle that PPiases can be selectively targeted.
Pyrrole synthesis using a tandem Grubbs' carbene-RuCl3 catalytic system
Dieltiens, Nicolai,Stevens, Christian V.,Vos, David De,Allaert, Bart,Drozdzak, Renata,Verpoort, Francis
, p. 8995 - 8998 (2004)
A straightforward pyrrole synthesis from diallylamines is developed by using a tandem catalyst system leading to ring-closing metathesis with the second generation Grubbs' catalyst (10%) followed by dehydrogenation in the presence of RuCl3 × H2O (2%).
A new method to N-arylmethylenepyrroles from N-acylpyrroles
D'Silva, Claudius,Iqbal, Rifat
, p. 457 - 458 (1996)
An efficient general method for the preparation of N-arylmethylenepyrroles based on the reduction of N-acylpyrroles is reported. The reduction procedure described is sufficiently mild to make it applicable to a variety of sensitive acyl and heterocyclic acyl compounds where reduction results in cleavage of the C-N bond. The method can also be used in the preparation of pyrrole derivatives containing base sensitive protecting groups.
Palladium-promoted 1,4-Cycloamination of 1,3-Dienes to Pyrroles
Baeckvall, Jan-E.,Nystroem, Jan-E.
, p. 59 - 61 (1981)
1,3-Dienes react with palladium(II) chloride and acetic acid with the formation of 4-acetoxy-alk-2-enyl-palladium complexes (2), which on reaction with primary amines give N-alkylpyrroles.
Arylation of indoles using cyclohexanones dually-catalyzed by niobic acid and palladium-on-carbons
Ban, Kazuho,Sajiki, Hironao,Sawama, Yoshinari,Yamamoto, Yuta
supporting information, p. 3898 - 3902 (2020/06/03)
3-Arylindoles were easily constructed from indoles and cyclohexanone derivatives using a combination of catalytic niobic acid-on-carbon (Nb2O5/C) and palladium-on-carbon (Pd/C) under heating conditions without any oxidants. The Lewis acidic Nb2O5/C promoted the nucleophilic addition of indoles to the cyclohexanones, and the subsequent dehydration and Pd/C-catalyzed dehydrogenation produced the 3-arylindoles. The additive 2,3-dimethyl-1,3-butadiene worked as a hydrogen acceptor to facilitate the dehydrogenation step.
Lactam derivatives and preparation method and application thereof
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Paragraph 0066-0070, (2020/02/10)
The invention relates to lactam derivatives and a preparation method and application thereof. Compared with the prior art, the invention provides lactam compounds with a novel structure. The compoundsand compositions thereof have remarkable activity in inhibition of the proliferation of cancer cells (including, but not limited to, the liver cancer cell line HepG2 and the lung cancer cell line A549), and the activity of multiple compounds is in the same order of magnitude as the activity of the commercial drug adriamycin or superior to the activity of adriamycin. The compounds of the inventioncan be prepared from N-substituted pyrrole compounds through a reaction, and the preparation method is convenient, rapid and efficient.
Sulfoxide-Promoted Chlorination of Indoles and Electron-Rich Arenes with Chlorine as Nucleophile
Ji, Yuan-Zhao,Li, Hui-Jing,Wang, Yi-Ruo,Wu, Yan-Chao,Zhang, Zheng-Yan
supporting information, (2020/02/05)
An efficient chlorination of indoles and electron-rich arenes with chlorine anion as nucleophile is described. With the use of ethyl phenyl sulfoxide as the promoter, the reaction went smoothly under metal-free and mild conditions. Various indoles and electron-rich arenes are converted into the corresponding chlorinated compounds in moderate to excellent yields. A plausible interrupted Pummerer reaction mechanism was proposed without the oxidation of chloride anion. In addition, the byproduct thioether could be easily converted to the starting material sulfoxide just by a simple oxidation reaction. (Figure presented.).
Development of Pd(OAc)2-catalyzed tandem oxidation of C[sbnd]N, C[sbnd]C, and C(sp3)–H bonds: Concise synthesis of 1-aroylisoquinoline, oxoaporphine, and 8-oxyprotoberberine alkaloids
Nishimoto, Saeko,Nakahashi, Hiromichi,Toyota, Masahiro
, (2020/11/13)
A catalytic tandem oxidation of C[sbnd]N, C[sbnd]C, and C(sp3)–H bonds is developed. This tandem oxidation is applied to two-step total syntheses of papaveraldine and pulcheotine A. Additionally, the total synthesis of liriodenine is achieved in six steps from homopiperonyl alcohol and 2-bromophenylacetonitrile by applying this catalytic tandem oxidation. Moreover, the direct conversion of xylopinine to 8-oxypseudopalmatine in a 76% yield demonstrates the versatility of this catalytic reaction.
Sustainable Manganese-Catalyzed Solvent-Free Synthesis of Pyrroles from 1,4-Diols and Primary Amines
Borghs, Jannik C.,Lebedev, Yury,Rueping, Magnus,El-Sepelgy, Osama
supporting information, p. 70 - 74 (2019/01/11)
A general and selective metal-catalyzed conversion of biomass-derived primary diols and amines to the highly valuable 2,5-unsubstituted pyrroles has been developed. The reaction is catalyzed by a stable nonprecious manganese complex (1 mol %) in the absence of organic solvents whereby water and molecular hydrogen are the only side products. The manganese catalyst shows unprecedented selectivity, avoiding the formation of pyrrolidines, cyclic imides, and lactones.
