1085-42-3Relevant articles and documents
Sulfonium ion-promoted traceless Schmidt reaction of alkyl azides
Ardiansah, Bayu,Kakiuchi, Kiyomi,Morimoto, Tsumoru,Tanimoto, Hiroki,Tomohiro, Takenori
, p. 8738 - 8741 (2021/09/08)
Schmidt reaction by sulfonium ions is described. General primary, secondary, and tertiary alkyl azides were converted to the corresponding carbonyl or imine compounds without any trace of the activators. This bond scission reaction through 1,2-migration of C-H and C-C bonds was accessible to the one-pot substitution reaction.
MOF-derived cobalt nanoparticles catalyze a general synthesis of amines
Jagadeesh, Rajenahally V.,Murugesan, Kathiravan,Alshammari, Ahmad S.,Neumann, Helfried,Pohl, Marga-Martina,Radnik, J?rg,Beller, Matthias
, p. 326 - 332 (2017/09/28)
The development of base metal catalysts for the synthesis of pharmaceutically relevant compounds remains an important goal of chemical research. Here, we report that cobalt nanoparticles encapsulated by a graphitic shell are broadly effective reductive amination catalysts. Their convenient and practical preparation entailed template assembly of cobaltdiamine- dicarboxylic acid metal organic frameworks on carbon and subsequent pyrolysis under inert atmosphere.The resulting stable and reusable catalysts were active for synthesis of primary, secondary, tertiary, and N-methylamines (more than 140 examples).The reaction couples easily accessible carbonyl compounds (aldehydes and ketones) with ammonia, amines, or nitro compounds, and molecular hydrogen under industrially viable and scalable conditions, offering cost-effective access to numerous amines, amino acid derivatives, and more complex drug targets.
Use of fenoterol and fenoterol analogues in the treatment of glioblastomas and astrocytomas
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Page/Page column 36; 55, (2016/12/07)
This disclosure concerns the discovery of the use of fenoterol and (R,R)- and (R,S)-fenoterol analogs for the treatment of a tumor expressing a β2-adrenergic receptor, such as a primary brain tumor, including a glioblastoma or astrocytoma expressing a β2-adrenergic receptor. In one example, the method includes administering to a subject a therapeutically effective amount of fenoterol, a specific fenoterol analog or a combination thereof to reduce one or more symptoms associated with the tumor, thereby treating the tumor in the subject.
Broadening the chemical scope of laccases: Selective deprotection of N-benzyl groups
Martínez-Montero, Lía,Díaz-Rodríguez, Alba,Gotor, Vicente,Gotor-Fernández, Vicente,Lavandera, Iván
supporting information, p. 2794 - 2798 (2015/05/27)
Laccase from Trametes versicolor together with TEMPO has been found to be a very efficient system to deprotect N-benzylated primary amines, differing from previously described methods since it uses oxygen as a mild oxidant in aqueous medium. Chemoselective removal of the benzyl group was achieved with excellent yields when secondary amines and alcohol moieties were also present.
Bis(amidate)bis(amido) titanium complex: A regioselective intermolecular alkyne hydroamination catalyst
Yim, Jacky C.-H.,Bexrud, Jason A.,Ayinla, Rashidat O.,Leitch, David C.,Schafer, Laurel L.
, p. 2015 - 2028 (2014/04/03)
An efficient and selective bis(amidate)bis(amido) titanium precatalyst for the anti-Markovnikov hydroamination of alkynes is reported. Hydroamination of terminal and internal alkynes with primary alkylamines, arylamines, and hydrazines is promoted by 5-10 mol % of Ti catalyst. Various functional groups are tolerated including esters, protected alcohols, and imines. The in situ generated complex shows comparable catalytic activity, demonstrating its synthetic versatility for benchtop application. Applications of this catalyst for the synthesis of amino alcohols and a one-pot procedure for indole synthesis are described. A mechanistic proposal that invokes turnover-limiting protonolysis is presented to rationalize the observed regioselectivities.
An (Aminopyrimidinato)titanium catalyst for the hydroamination of alkynes and alkenes
Brahms, Christian,Tholen, Patrik,Saak, Wolfgang,Doye, Sven
, p. 7583 - 7592 (2013/12/04)
A new (aminopyrimidinato)titanium complex has been synthesised from inexpensive and easily accessible 2-(tert-butylamino)pyrimidine and [Ti(NMe 2)4] and used as a catalyst for the intermolecular hydroamination of alkynes as well as the cyclization of aminoalkenes. The hydroamination reactions of 1-phenylpropyne and terminal arylalkynes deliver the corresponding anti-Markovnikov addition products with excellent yields and regioselectivities. A new (aminopyrimidinato)titanium complex has been synthesised from inexpensive 2-(tert-butylamino)pyrimidine and [Ti(NMe 2)4] and used as a catalyst for the intermolecular hydroamination of alkynes as well as the cyclization of aminoalkenes. The complex represents the first example of a catalyst for the hydroamination of alkynes that contains an aminoheteroaromatic ancillary ligand.
PREPARATION OF (R,R)-FENOTEROL AND (R,R)- OR (R,S)-FENOTEROL ANALOGUES AND THEIR USE IN TREATING CONGESTIVE HEART FAILURE
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Page/Page column 40, (2008/06/13)
This disclosure concerns the discovery of (R,R)- and (R,S)-fenoterol analogues which are highly effective at binding β2-adrenergic receptors. Exemplary chemical structures for these analogues are provided. Also provided are pharmaceutical compositions including the disclosed (R,R)-fenoterol and fenoterol analogues, and methods of using such compounds and compositions for the treatment of cardiac disorders such as congestive heart failure and pulmonary disorders such as asthma or chronic obstructive pulmonary disease.
Comparative molecular field analysis of the binding of the stereoisomers of fenoterol and fenoterol derivatives to the β2 adrenergic receptor
Jozwiak, Krzysztof,Khalid, Chakir,Tanga, Mary J.,Berzetei-Gurske, Ilona,Jimenez, Lucita,Kozocas, Joseph A.,Woo, Anthony,Zhu, Weizhong,Xiao, Rui-Ping,Abernethy, Darrell R.,Wainer, Irving W.
, p. 2903 - 2915 (2008/02/07)
Stereoisomers of fenoterol and six fenoterol derivatives have been synthesized and their binding affinities for the β2 adrenergic receptor (Kiβ2-AR), the subtype selectivity relative to the β1-AR (Kiβ1-AR/K iβ2-AR) and their functional activities were determined. Of the 26 compounds synthesized in the study, submicromolar binding affinities were observed for (R,R)-fenoterol, the (R,R)-isomer of the p-methoxy, and (R,R)- and (R,S)-isomers of 1-naphthyl derivatives and all of these compounds were active at submicromolar concentrations in cardiomyocyte contractility tests. The Kiβ1-AR/K iβ2-AR ratios were >40 for (R,R)-fenoterol and the (R,R)-p-methoxy and (R,S)-1-naphthyl derivatives and 14 for the (R,R)-1-napthyl derivative. The binding data was analyzed using comparative molecular field analysis (CoMFA), and the resulting model indicated that the fenoterol derivatives interacted with two separate binding sites and one steric restricted site on the pseudo-receptor and that the chirality of the second stereogenic center affected Kiβ2 and subtype selectivity.
Base-catalyzed anti-Markovnikov hydroamination of vinylarenes - Scope, limitations and computational studies
Horrillo-Martinez, Patricia,Hultzsch, Kai C.,Gil, Adria,Branchadell, Vicenc
, p. 3311 - 3325 (2008/02/10)
The hydroamination of vinylarenes with primary and secondary amines was studied with catalytic amounts as low as 2 mol-% of LiN(SiMe3) 2/TMEDA. Reactions proceeded readily at 120°C in the absence of solvent to give selective anti-Markovnikov addition. Slow addition was observed at 25°C with either electron-deficient p-chlorostyrene or secondary cyclic amines such as pyrrolidine, piperidine, or morpholine. Primary amines were prone to a second hydroamination reaction to form tertiary amine byproducts. The selectivity for the mono(hydroamination) products could be improved with a two-fold excess of the amine. KN(SiMe3)2 showed higher catalytic activity but lower selectivity in comparison to that of LiN(SiMe 3)2, resulting in undesired C-H-activation by-products. The mechanism of the lithium-catalyzed hydroamination and the influence of TMEDA was studied with density functional theory. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
[Ind2TiMe2]: A general catalyst for the intermolecular hydroamination of alkynes
Heutling, Andreas,Pohlki, Frauke,Doye, Sven
, p. 3059 - 3071 (2007/10/03)
[Ind2TiMe2] (Ind=indenyl) is a highly active and general catalyst for the intermolecular hydroamination of alkynes. It catalyzes the reaction of primary aryl-, tert-alkyl-, sec-alkyl-, and nalkylamines with internal and terminal alkynes. In the case of unsymmetrically substituted 1-phenyl-2-alkylalkynes, the reactions occur with modest to excellent regioselectivities, whereby formation of the anti-Markovnikov regioisomers is favored. While the major product of hydroamination reactions of terminal arylalkynes is always the anti-Markovnikov isomer, alkylalkynes react with arylamines to preferably give the Markovnikov products. To achieve reasonable rates for the addition of sterically less hindered n-alkyland benzylamines to alkynes, these amines must be added slowly to the reaction mixtures. This behavior is explained by the fact that the catalytic cycle proposed on the basis of an initial kinetic investigation includes the possibility that the rate of the reaction increases with decreasing concentration of the employed amine. Furthermore, no dimerization of the catalytically active imido complex is observed in the hydroamination of 1-phenylpropyne with 4-methylaniline in the presence of [Ind2TiMe2] as catalyst. In general, a combination of [Ind2TiMe2]-catalyzed hydroamination of alkynes with subsequent reduction leads to the formation of secondary amines with good to excellent yields. Particularly impressive is that [Ind 2TiMe2] makes it possible for the first time to perform the reactions of n-alkyl- and benzylamines with 1-phenylpropyne in a highly regioselective fashion.
