128165-52-6Relevant academic research and scientific papers
Generation, optimization and characterization of novel anti-prion compounds
Altieri, Andrea,Biasini, Emiliano,Biggi, Silvia,Ishibashi, Daisuke,Kurkin, Alexander V.,Nishida, Noriyuki,Sivtzev, Semen I.,Spiridonov, Evgeny A.
, (2020/09/09)
Prions are misfolded proteins involved in neurodegenerative diseases of high interest in veterinary and public health. In this work, we report the chemical space exploration around the anti-prion compound BB 0300674 in order to gain an understanding of its Structure Activity Relationships (SARs). A series of 43 novel analogues, based on four different chemical clusters, were synthetized and tested against PrPSc and mutant PrP toxicity assays. From this biological screening, two compounds (59 and 65) emerged with a 10-fold improvement in anti-prion activity compared with the initial lead compound, presenting at the same time interesting cell viability.
Nucleophilic Organic Base DABCO-Mediated Chemospecific Meinwald Rearrangement of Terminal Epoxides into Methyl Ketones
Li, Siqi,Shi, Yi,Li, Pingfan,Xu, Jiaxi
, p. 4443 - 4450 (2019/04/30)
Nucleophilic organic base DABCO (1,4-diazabicyclo[2.2.2]octane)-mediated Meinwald rearrangement of various epoxides was investigated. 2-Aryl-, alkenyl-, and alkynylepoxides generate the corresponding methyl ketones chemospecifically in good to excellent yields. The current DABCO-mediated Meinwald rearrangement of epoxides features readily accessible starting materials, a wide substrate scope, a transition-metal- and acid-free environment, and chemospecificity in the isomerization of epoxides.
Copper-catalyzed silylation reactions of propargyl epoxides: Easy access to 2,3-allenols and stereodefined alkenes
Chang, Xi-Hao,Liu, Zheng-Li,Luo, Yun-Cheng,Yang, Chao,Liu, Xiao-Wei,Da, Bing-Chao,Li, Jie-Jun,Ahmad, Tanveer,Loh, Teck-Peng,Xu, Yun-He
supporting information, p. 9344 - 9347 (2017/08/23)
Efficient silylation reactions of propargyl epoxides catalyzed by copper catalysts have been developed. Under mild reaction conditions, tri- and tetra-substituted functionalized allenols and alkenes could be selectively obtained in moderate to high yields
Chemo-, regio-, and stereo-selective perfluoroalkylations by a Grignard complex with zirconocene
Fujiu, Motohiro,Negishi, Kazuyuki,Guang, Jie,Williard, Paul G.,Kuroki, Shigeki,Mikami, Koichi
supporting information, p. 19464 - 19468 (2015/11/27)
The synthesis of highly reactive perfluoroalkyl Grignard reagents with early transition metal zirconocene complexes and their new types of highly chemo-, regio-, and stereo-selective perfluoroalkylation reactions are reported with epoxides in particular. The zirconocene complex is advantageous in activating the perfluoroalkyl Grignard species. The zirconocene·Grignard complexes were clarified by DOSY. Both 1H and 19F DOSY analyses show that the addition of MAO and dioxane to the mixture of RFMgCl and Cp2ZrCl2 connects Cp2Zr and RFMg to generate the zirconocene/perfluoroalkyl-Grignard/dioxane complex.
Leveraging the micellar effect: Gold-catalyzed dehydrative cyclizations in water at room temperature
Minkler, Stefan R. K.,Isley, Nicholas A.,Lippincott, Daniel J.,Krause, Norbert,Lipshutz, Bruce H.
supporting information, p. 724 - 726 (2014/03/21)
The first examples of gold-catalyzed cyclizations of diols and triols to the corresponding hetero- or spirocycles in an aqueous medium are presented. These reactions take place within nanomicelles, where the hydrophobic effect is operating, thereby driving the dehydrations, notwithstanding the surrounding water. By the addition of simple salts such as sodium chloride, reaction times and catalyst loadings can be significantly decreased.
Mechanistic investigations of cooperative catalysis in the enantioselective fluorination of epoxides
Kalow, Julia A.,Doyle, Abigail G.
supporting information; experimental part, p. 16001 - 16012 (2011/11/13)
This report describes mechanistic studies of the (salen)Co- and amine-cocatalyzed enantioselective ring opening of epoxides by fluoride. The kinetics of the reaction, as determined by in situ 19F NMR analysis, are characterized by apparent first-order dependence on (salen)Co. Substituent effects, nonlinear effects, and reactivity with a linked (salen)Co catalyst provide evidence for a rate-limiting, bimetallic ring-opening step. To account for these divergent data, we propose a mechanism wherein the active nucleophilic fluorine species is a cobalt fluoride that forms a resting-state dimer. Axial ligation of the amine cocatalyst to (salen)Co facilitates dimer dissociation and is the origin of the observed cooperativity. On the basis of these studies, we show that significant improvements in the rates, turnover numbers, and substrate scope of the fluoride ring-opening reactions can be realized through the use of a linked salen framework. Application of this catalyst system to a rapid (5 min) fluorination to generate the unlabeled analog of a known PET tracer, F-MISO, is reported.
Convenient access to functionalized vinylcyclopentenols from alkynyloxiranes
Wang, Letian,Maddess, Matthew L.,Lautens, Mark
, p. 1822 - 1825 (2007/10/03)
β,γ-Alkynyl aldehydes, generated in situ by treatment of alkynyloxiranes with a catalytic amount of Sc(OTf)3 or BF 3· OEt2, are effectively trapped by a variety of allyl nucleophiles to afford homopropargylic homoallylic a
Synthesis of alkylidenecyclopentenones and dialkylidenecyclopentenones via the coupling of propargylic alcohol and 2-alkyne-1,4-diol derivatives with cyclopropylcarbene-chromium complexes
Herndon, James W.,Zhu, Jin,Sampedro, Diego
, p. 4985 - 4993 (2007/10/03)
The coupling of propargylic alcohols and their derivatives with cyclopropylcarbene-chromium complexes has been investigated. The coupling reaction leads to alkylidenecyclopentenones or alkoxyalkyl-cyclopentenones, depending on the leaving group ability of
Novel (α,β-Epoxyalkyl)lithium Reagents via the Lithiation of Organyl-Substituted Epoxides
Eisch, John J.,Galle, James E.
, p. 4835 - 4840 (2007/10/02)
A series of epoxides bearing unsaturated organyl groups attached directly to the epoxy group was found to have sufficient kinetic acidity to undergo clean lithiation at low temperatures.Epoxides of the type is aryl, vinylic, acetylenic, alkoxycarbonyl, or cyano, were smoothly converted into by either t-BuLi or LDA in the temperature range of -80 to -115 deg C.The resulting (α,β-epoxyalkyl)lithium reagents could be transformed into a variety of substituted epoxides, such as R2C-CE(Un)-O, where E = D, R3Si, R3Sn, R, RCO, CO2H, or COH(R)2.In cases where Un is acyl, addition to the carbonyl, rather than lithiation, occurred preferentially.Attempted lithiations of aziridines and thiiranes led to extrusion of nitrogen and sulfur, respectively.Even the relatively stable intermediates generated at -90 deg C underwent carbenoid-like decomposition at higher temperatures to yield isomerization and intermolecular-insertion products.Observation of these processes gives direct corroboration of reaction mechanisms proposed for the base-promoted isomerizations of epoxides.
