19655-56-2Relevant academic research and scientific papers
Cobalt-catalyzed ring-opening addition of azabenzonorbornadienes: Via C(sp3)-H bond activation of 8-methylquinoline
Tan, Heng,Khan, Ruhima,Xu, Dandan,Zhou, Yongyun,Zhang, Xuexin,Shi, Guangrui,Fan, Baomin
, p. 12570 - 12573 (2020)
The first ring-opening addition of a benzylic C(sp3)-H bond to azabenzonorbornadienes is demonstrated. The reaction proceeded under the catalytic system of [Cp?CoI2(CO)], AgSbF6 and Fe(OAc)2 in PhOMe. The methodology showed a good substrate scope with up to 96 yield. The relative configuration of the product was determined as cis-configuration by X-ray crystallography.
Cp*Rh(III)-Catalyzed Regioselective C(sp3)-H Methylation of 8-Methylquinolines with Organoborons
Kumar, Rakesh,Sharma, Ritika,Kumar, Rohit,Sharma, Upendra
, p. 305 - 309 (2020)
Rh(III)-catalyzed highly regioselective methylation of the unactivated C(sp3)-H bond of 8-methylquinolines with bench stable organoboron reagents is described. A variety of substituted 8-methylquinolines provided the highly regioselective monom
Design and development of photoswitchable DFG-Out RET kinase inhibitors
Andréasson, Joakim,Andreasson, M?ns,Carrasco, Marta P.,Fleming, Cassandra,Gao, Chunxia,Gr?tli, Morten,H?versen, Liliana,Lundb?ck, Thomas,Xu, Yongjin
, (2022/03/23)
REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase that is required for development of multiple human tissues, but which is also an important contributor to human cancers. RET activation through rearrangement or point mutations occurs in thyroid and lung cancers. Furthermore, activation of wild type RET is an increasingly recognized mechanism promoting tumor growth and dissemination of a much broader group of cancers. RET is therefore an attractive therapeutic target for small-molecule kinase inhibitors. Non-invasive control of RET signaling with light offers the promise of unveiling its complex spatiotemporal dynamics in vivo. In this work, photoswitchable DFG-out RET kinase inhibitors based on heterocycle-derived azobenzenes were developed, enabling photonic control of RET activity. Based on the binding mode of DFG-out kinase inhibitors and using RET kinase as the test model, we developed a photoswitchable inhibitor with a quinoline “head” constituting the azoheteroarene. This azo compound was further modified by three different strategies to increase the difference in biological activity between the E-isomer and the light enriched Z-isomer. Stilbene-based derivatives were used as model compounds to guide in the selection of substituents that could eventually be introduced to the corresponding azo compounds. The most promising quinoline-based compound showed more than a 15-fold difference in bioactivity between the two isomers in a biochemical assay. However, the same compound showed a decreased Z/E (IC50) ratio in the cellular assay, tentatively assigned to stability issues. The corresponding stilbene compound gave a Z/E (IC50) ratio well above 100, consistent with that measured in the biochemical assay. Ultimately, a 7-azaindole based photoswitchable DFG-out kinase inhibitor was shown to display more than a 10-fold difference in bioactivity between the two isomers, in both a biochemical and a cell-based assay, as well as excellent stability even under reducing conditions.
Cobalt-catalysed C–H methylation for late-stage drug diversification
Ackermann, Lutz,Friis, Stig D.,Johansson, Magnus J.
, p. 511 - 519 (2020/06/05)
The magic methyl effect is well acknowledged in medicinal chemistry, but despite its significance, accessing such analogues via derivatization at a late stage remains a pivotal challenge. In an effort to mitigate this major limitation, we here present a strategy for the cobalt-catalysed late-stage C–H methylation of structurally complex drug molecules. Enabling broad applicability, the transformation relies on a boron-based methyl source and takes advantage of inherently present functional groups to guide the C–H activation. The relative reactivity observed for distinct classes of functionalities were determined and the sensitivity of the transformation towards a panel of common functional motifs was tested under various reaction conditions. Without the need for prefunctionalization or postdeprotection, a diverse array of marketed drug molecules and natural products could be methylated in a predictable manner. Subsequent physicochemical and biological testing confirmed the magnitude with which this seemingly minor structural change can affect important drug properties. [Figure not available: see fulltext.]
Non-electronic aromatic ring activation by simple steric repulsion between substituents in 1-methylquinolinium salt systems
Iwai, Kento,Yokoyama, Soichi,Asahara, Haruyasu,Nishiwaki, Nagatoshi
, p. 50 - 57 (2020/01/21)
A systematic study of non-electronic activation of an aromatic ring was performed using a series of 8-substituted 1-methylquinolinium salts. As the 8-substituent became bulkier, the quinoline framework was distorted by steric repulsion between substituents at the 1- A nd 8-positions. This was accompanied by lack of coplanarity, which brought about dearomatization. Consequently, quinolinium ions possessing a bulky 8-substituent exhibited high reactivity undergoing nucleophilic addition at the 2-position efficiently. We demonstrate that the activation was achieved sterically and not electronically.
Cp*RhIII-Catalyzed Sterically Controlled C(sp3)?H Selective Mono- and Diarylation of 8-Methylquinolines with Organoborons
Chandra, Devesh,Dhiman, Ankit Kumar,Gupta, Shiv Shankar,Kumar, Rakesh,Parmar, Diksha,Sharma, Upendra
supporting information, (2020/03/23)
Herein, the RhIII-catalyzed selective monoarylation and diarylation (symmetrical and unsymmetrical) of 8-methylquinolines with organoboron reagents are disclosed. The selective monoarylation of primary C(sp3)?H bonds is achieved by using 7-substituted 8-methylquinolines or by changing the quantity of the aryl boronic acids. The method is also applicable for the arylation of 2-ethylpyridines, and the heteroarylation with thiophene-2-ylboronic acids. Symmetrical and unsymmetrical diarylation of 8-methylquinolines have been carried out in one-pot and sequential manner, respectively. Late-stage monoarylation of oxime derivatives and gram-scale synthesis of monoarylated products has also been carried out. A mechanistic study revealed that the current reaction is first order with respect to both reactants and a five-membered rhodacycle intermediate may be involved in the catalytic cycle.
Pd-Catalyzed Alkylation of (Iso)quinolines and Arenes: 2-Acylpyridine Compounds as Alkylation Reagents
Wu, Qingsong,Han, Shuaijun,Ren, Xiaoxiao,Lu, Hongtao,Li, Jingya,Zou, Dapeng,Wu, Yangjie,Wu, Yusheng
supporting information, p. 6345 - 6348 (2018/10/20)
The first Pd-catalyzed alkylation of (iso)quinolines and arenes is reported. The readily available and bench-stable 2-acylpyridine compounds were used as an alkylation reagent to form the structurally versatile alkylated (iso)quinolines and arenes. The method affords a convenient pathway for the introduction of alkyl groups into organic molecules.
Cp?Rh(III)-Catalyzed Mild Addition of C(sp3)-H Bonds to α,β-Unsaturated Aldehydes and Ketones
Liu, Bingxian,Hu, Panjie,Zhou, Xukai,Bai, Dachang,Chang, Junbiao,Li, Xingwei
supporting information, p. 2086 - 2089 (2017/04/28)
A Rh(III)-catalyzed addition of benzylic C(sp3)-H bond to α,β-unsaturated ketones/aldehydes has been realized, leading to efficient synthesis of γ-aryl ketones/aldehydes. This atom-economic reaction proceeded under mild and redox-neutral conditions with a broad substrate scope. Besides benzylic C-H, allylic C-H bonds are also applicable when assisted by O-methyl ketoxime directing groups.
Synthesis of quinolines by iron-catalyzed reaction of anilines with propane-1,3-diol
Khusnutdinov,Bayguzina,Aminov
, p. 2725 - 2727 (2016/02/18)
Quinoline and its derivatives were synthesized by cyclocondensation of anilines with propane-1,3-diol in 57-96% yield in the presence of iron-containing catalysts in carbon tetrachloride.
Gold-catalyzed highly regioselective oxidation of C-C triple bonds without acid additives: Propargyl moieties as masked α,β-unsaturated carbonyls
Lu, Biao,Li, Chaoqun,Zhang, Liming
supporting information; experimental part, p. 14070 - 14072 (2011/01/04)
Gold-catalyzed intermolecular oxidations of internal alkynes have been achieved with high regioselectivities using 8-alkylquinoline N-oxides as oxidants and in the absence of acid additives. Synthetically versatile α,β-unsaturated carbonyls are obtained in good to excellent yields and with excellent E-selectivities. A range of functional groups such as THP, MOMO, N3, OTBS, and N-Boc are tolerated. This reaction allows α,β-unsaturated carbonyls to be masked as propargyl moieties, thus offering a practical solution to compatibility issues with these functional groups likely encountered in syntheses of complex structures.
