38079-40-2Relevant academic research and scientific papers
Cascade Synthesis of Kinase-Privileged 3-Aminoindazoles via Intramolecular N-N Bond Formation
Zhu, W. Felix,Kr?mer, Andreas,Knapp, Stefan,Proschak, Ewgenij,Hernandez-Olmos, Victor
, p. 3856 - 3862 (2022/03/02)
3-Aminoindazoles are privileged scaffolds for bioactive drug-like molecules. In this study, a microwave-assisted cascade reaction for the synthesis of N-1 substituted 3-aminoindazoles with yields up to 81% has been developed. Starting from 3-(2-bromoaryl)-1,2,4-oxadiazol-5(4H)-ones, the reaction exhibits a broad substrate scope including anilines, aliphatic amines, and sulfonamides and bypasses selectivity issues between N-1 and 3-amino group. Furthermore, the Differential Scanning Fluorimetry screen of a kinase panel demonstrated the value of targeting N-1 substituted 3-aminoindazoles as kinase-biased fragments.
Copper-Catalyzed N1 Coupling of 3-Aminoindazoles and Related Aminoazoles with Aryl Bromides
Cyr, Patrick,Joseph-Valcin, Eve-Marline,Boissarie, Patrick,Simoneau, Bruno,Marinier, Anne
supporting information, (2021/12/02)
The N1-selective arylation of 3-aminoindazoles using copper catalysis is herein reported. The reaction uses readily accessible aryl bromides as coupling partners, including those from heterocycles, and allows easy access to a broad variety of substituted 3-aminoindazoles. The methodology was also examined on other aminoazoles of interest for the pharmaceutical industry.
Method for preparing substituted 3-aminoindazole compound in one step
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Paragraph 0023-0027; 0116-0119, (2020/07/28)
The invention discloses a method for preparing a substituted 3-aminoindazole compound in one step, and belongs to the technical field of organic chemical synthesis. According to the method, simple nitrile and hydrazine compounds are adopted as initial raw
Rapid access to 3-aminoindazoles from nitriles with hydrazines: A strategy to overcome the basicity barrier imparted by hydrazines
Zhang, Chunyan,Zhao, Haowen,Li, Zehua,Liang, Zuyu,Qi, Shuo,Cai, Mingyu,Zhang, Sheng,Jia, Xiaofei,Zhang, Guoying,Hu, Mao-Lin
supporting information, p. 9521 - 9524 (2020/09/02)
A practical and efficient base mediated synthesis of free 3-aminoindazoles has been developed from the reaction of nitriles with hydrazines, which successfully overcomes the difficulty of using aromatic hydrazines as substrates and allows for the synthesis of a wide range of N-aryl substituted free 3-aminoindazoles in moderate to excellent yields under mild conditions in one-pot. This finding provides a rapid and useful strategy for the synthesis of various functionalized 3-aminoindazole derivatives. This journal is
C4-C5 fused pyrazol-3-amines: When the degree of unsaturation and electronic characteristics of the fused ring controls regioselectivity in Ullmann and acylation reactions
Borrell, José I.,Bou-Petit, Elisabeth,Estrada-Tejedor, Roger,Font-Bardia, Mercè,Plans, Arnau,Puigjaner, Cristina,Ramon Y Cajal, Santiago,Rodríguez-Picazo, Nieves,Teixidó, Jordi,Torres-Coll, Antoni
, p. 5145 - 5156 (2020/07/23)
Pyrazol-3-amine is a scaffold present in a large number of compounds with a wide range of biological activities and, in many cases, the heterocycle is C4-C5 fused to a second ring. Among the different reactions used for the decoration of the pyrazole ring, Ullmann and acylation have been widely applied. However, there is some confusion in the literature regarding the regioselectivity of such reactions (substitution at N1 or N2 of the pyrazole ring) and no predictive rule has been so far established. As a part of our work on 3-amino-pyrazolo[3,4-b]pyridones 13, we have studied the regioselectivity of such reactions in different C4-C5 fused pyrazol-3-amines. As a rule of thumb, the Ullmann and acylation reactions take place, predominantly, at the NH and non-protonated nitrogen atom of the pyrazole ring respectively, of the most stable initial tautomer (1H- or 2H-pyrazole), which can be easily predicted by using DFT calculations. This journal is
Copper immobilized at a covalent organic framework: An efficient and recyclable heterogeneous catalyst for the Chan-Lam coupling reaction of aryl boronic acids and amines
Han, Yi,Zhang, Mo,Zhang, Ya-Qing,Zhang, Zhan-Hui
, p. 4891 - 4900 (2018/11/21)
A polyimide covalent organic framework (PI-COF) with high thermal and chemical stabilities has been readily prepared from commercially available and inexpensive reagents and was employed as an effective support for heterogeneous copper. It was demonstrated that the obtained Cu@PI-COF is a highly active heterogeneous catalyst which can effectively promote the Chan-Lam coupling reaction of aryl boronic acids and amines in an open flask without the aid of any base or additive. In addition, the catalyst could be readily recovered from the reaction mixture by simple filtration and reused for at least eight cycles without any observable change in structure and catalytic activity.
Assembly of substituted 3-aminoindazoles from 2-bromobenzonitrile via a CuBr-catalyzed coupling/condensation cascade process
Xu, Lanting,Peng, Yinsheng,Pan, Qiangbiao,Jiang, Yongwen,Ma, Dawei
, p. 3400 - 3404 (2013/06/26)
CuBr-catalyzed coupling reaction of 2-halobenzonitriles with hydrazine carboxylic esters and CuBr/4-hydroxy-l-proline-catalyzed coupling reaction of 2-bromobenzonitriles with N′-arylbenzohydrazides proceed smoothly at 60-90 C to provide substituted 3-aminoindazoles through a cascade coupling/condensation (or coupling/deacylation/condensation) process. A wide range of 3-aminoindazoles with substituents at both the 1-position and the phenyl ring part can be prepared from the corresponding coupling partners.
Heterocyclic Rearrangements. N,N-Diphenylhydrazones, Oximes and O-Methyloximes of 3-Benzoyl-5-phenyl-1,2,4-oxadiazole
Vivona, Nicolo,Frenna, Vincenzo,Buscemi, Silvestre,Ruccia, Michele
, p. 97 - 99 (2007/10/02)
The behaviour of (E)- and (Z)-N,N-diphenylhydrazones and O-methyloximes of 3-benzoyl-5-phenyl-1,2,4-oxadiazole has been studied.When refluxed in benzene, or in dioxane-water (1:1), the (Z)-N,N-diphenylhydrazone 8Z gave the indazole 11 or the substituted s
