4370-96-1Relevant academic research and scientific papers
Rhodium-catalysed diastereo- And enantioselective cyclopropanation of α-boryl styrenes
Sun, Xiao,Gu, Peiming,Qin, Jiao,Su, Yan
supporting information, p. 12379 - 12382 (2020/10/30)
A rhodium-catalyzed diastereo- and enantio-selective cyclopropanation of a-boryl styrenes with a-diazoarylacetates was established. Rh2(S-PTTL)4 (0.2 mol%) was found to be effective for the conversion, and 21 diastereopure cyclopropylboronates were prepared in high yields with excellent enantioselectivity (ee up to 99%).
Cu/PCy3-Catalyzed Formal Carbene Insertion into Electron-Deficient C?H Bonds
Ren, Yuan-Yuan,Mao, Hong-Xiang,Hu, Meng-Yang,Zhu, Shou-Fei,Zhou, Qi-Lin
, p. 4267 - 4271 (2020/07/06)
A carbene insertion into electron-deficient C?H bonds of 1,3-diesters, β-ketoesters, β-ketonitriles, and malononitriles was realized by using CuCN/PCy3 as the catalyst. The reaction provides a straightforward approach to the synthetically important multi-substituted succinic acid derivatives. A plausible reaction mechanism with cyclopropanation/ring opening as key steps was proposed based on control experiments.
Design, synthesis and investigation of new diphenyl substituted pyridazinone derivatives as both cholinesterase and Aβ-aggregation inhibitors
Kilic, Burcu,Erdogan, Merve,Gulcan, Hayrettin O.,Aksakal, Fatma,Oruklu, Nihan,Bagriacik, Emin U.,Dogruer, Deniz S.
, p. 59 - 76 (2019/06/11)
Background: With respect to the increase in the average life expectancy, Alzheimer Disease (AD), the most common form of age-related dementia, has become a major threat to the population over the age of 65 during the past several decades. The majority of AD treatments are focused on cholinergic and amyloid hypotheses. Objective: In this study, three series of diphenyl-2-(2-(4-substitutedpiperazin-1-yl)ethyl)pyridazin- 3(2H)-one derivatives were designed, synthesized and investigated for their ability to inhibit both cholinesterase enzymes and amyloid-β aggregation. Method: The inhibitory activities of the synthesized compounds on AChE (from electric eel) and BChE (from equine serum) were determined by the modified Ellman’s method. The reported thioflavin T-based fluorometric assay was performed to investigate the effect of the selected compounds on the aggregation of Aβ1-42. The cytotoxic effect of the compounds (4g, 11g and 18g) was monitored in 3T3 cell lines to gain insight into therapeutic potential of the compounds by using MTT assay. The crystal structures of the AChE (1EVE) and BChE (1P0I) enzymes were retrieved from the RCSB Protein Data Bank and Molecular Operating Environment (MOE) software was used for molecular docking of the ligands. Results: Among the tested compounds, 5,6-diphenyl derivative 18g was identified as the most potent and selective AChE inhibitor (IC50 = 1.75 μM, Selectivity Index for AChE > 22.857). 4,6- Diphenyl derivative 11g showed the highest and the most selectivity for BChE (IC50= 4.97 μM, SI for AChE 0.124). Interestingly, 4,5-diphenyl derivative 4g presented dual cholinesterase inhibition (AChE IC50= 5.11 μM; BChE IC50= 14.16 μM, SI for AChE = 2.771). Conclusion: Based on biological activity results and low toxicity of the compounds, it can be said that diphenyl substituted pyridazinone core is a valuable scaffold. Especially, dual inhibitory potencies of 4,5-diphenylpyridazin-3(2H)-one core for the cholinesterase enzymes and Aβ- aggregation makes this core a promising disease-modifying agent.
Asymmetric Synthesis of α-Quaternary γ-Lactams through Palladium-Catalyzed Asymmetric Allylic Alkylation
Song, Tao,Arseniyadis, Stellios,Cossy, Janine
supporting information, p. 603 - 607 (2019/02/28)
The synthesis of chiral unsaturated γ-lactams is reported featuring a highly enantioselective palladium-catalyzed asymmetric allylic alkylation of α, γ-disubstituted 2-silyloxypyrroles. This method allows a straightforward access to optically active γ-lactams bearing an α-quaternary stereogenic center in high yields (up to 93%), high regioselectivities (up to >20:1), and excellent enantioselectivities (up to 95% ee). To further demonstrate the synthetic utility of the method, the resulting allylated products were converted to various versatile chiral building blocks, such as pyrrolidines and pyrrolidinones.
Catalyst-Dependent Chemoselective Formal Insertion of Diazo Compounds into C?C or C?H Bonds of 1,3-Dicarbonyl Compounds
Liu, Zhaohong,Sivaguru, Paramasivam,Zanoni, Giuseppe,Anderson, Edward A.,Bi, Xihe
, p. 8927 - 8931 (2018/05/14)
A catalyst-dependent chemoselective one-carbon insertion of diazo compounds into the C?C or C?H bonds of 1,3-dicarbonyl species is reported. In the presence of silver(I) triflate, diazo insertion into the C(=O)?C bond of the 1,3-dicarbonyl substrate leads
Formation of γ-oxoacids and 1 H-pyrrol-2(5 H)-ones from α,β-unsaturated ketones and ethyl nitroacetate
Aginagalde, Maialen,Bello, Tamara,Masdeu, Carme,Vara, Yosu,Arrieta, Ana,Cossio, Fernando P.
experimental part, p. 7435 - 7438 (2010/12/25)
Michael addition of ethyl nitroacetate on α,β-unsaturated ketones followed by Nef oxidation under hydrolytic conditions yields γ-oxoacids instead of the corresponding α,δ-dioxoesters. A concerted decarboxylation step is proposed on the basis of computational results. Finally, conversion of the γ-ketoacids thus prepared into 1H-pyrrol-2(5H)-ones by reaction with primary amines under Paal-Knorr conditions is also reported.
3,4,6-Substituted pyridazines for treating neuropathic pain and associated syndromes
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Page/Page column 17, (2008/06/13)
The present invention is directed to the use of 3,4,6-substituted pyridazines such as those characterized by structure I for treating conditions such as neuropathic pain among others.
THERAPEUTIC AGENT FOR DIABETES
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, (2008/06/13)
A therapeutic agent for diabetes, which comprises a compound of the formula [I] wherein Xis a group of the formula wherein R4and R5are the same or different and each is a hydrogen atom, an optionally substituted alkyl having 1 to 5 carbon atoms and the like, and R6is a hydrogen atom or an amino-protecting group; R1is an optionally substituted alkyl having 1 to 5 carbon atoms, an optionally substituted alkenyl having 2 to 6 carbon atoms and the like, R2is a hydrogen atom, an optionally substituted alkyl having 1 to 5 carbon atoms and the like, R2' is a hydrogen atom, and R3is an optionally substituted alkyl having 1 to 5 carbon atoms and the like, a prodrug thereof, a pharmaceutically acceptable salt thereof, a hydrate thereof and a solvate thereof. The compound of the present invention shows superior blood sugar decreasing action on the state of hyperglycemia, but does not affect the blood sugar when it is in the normal range or in the hypoglycemic state, which means that it is free of serious side effects such as hypoglycemia. Therefore, the compound of the present invention is useful as a therapeutic drug for diabetes and also useful as a preventive of the chronic complications of diabetes.
Formaldehyde dialkylhydrazones as neutral formyl anion and cyanide equivalents: Nucleophilic addition to conjugated enones
Diez,Fernandez,Gasch,Lassaletta,Llera,Martin-Zamora,Vazquez
, p. 5144 - 5155 (2007/10/03)
A versatile methodology for the nucleophihc formylation and cyanation of conjugated enones is reported. The procedure is based on the use of formaldehyde dimethylhydrazone, which, acting as a neutral formyl anion equivalent, adds to preformed trialkylsilyl-enone complexes. Both 4-(silyl- oxy)-3-enal hydrazones 3 or deprotected 4-oxo aldehyde monohydrazones 4 can be obtained at products depending on quenching conditions. In full analogy, an asymmetric version of the reaction using chiral formaldehyde SAMP- hydrazone as a neutral synthon of the chiral formyl anion has been developed, giving rise to the corresponding adducts 5 and 6 in good yields and with excellent diastereoselectivities (de 85-≤98%). Ozonolysis or HCl-mediated hydrolysis of adducts 4 and 6 readily affords racemic and optically enriched 4-oxo aldehydes 7, respectively. Additionally, high-yielding MMPP-oxidative cleavage of 4-oxo hydrazones 4 and 6 has been performed to obtain 4-oxo nitriles 8 in racemic and optically enriched forms, respectively. In this way, interesting chiral bifunctional building blocks, some of them bearing newly created stereogenic quaternary centers, have been efficiently synthesized.
A New Synthetic Route to 4,6-Diarylpyridazinones and Some of their Derivatives
Coudert, P.,Couquelet, J.,Tronche, P.
, p. 799 - 802 (2007/10/02)
A novel approach to the titled ring system starting from conveniently available chalcones 1 is proposed.It involves a catalysed exchange of hydrogen cyanide between acetone cyanohydrin and 1.The resulting γ-ketonitriles 2 give the expected 4,6-diarylpyrid
