27049-45-2Relevant academic research and scientific papers
Phenyl-1-Pyridin-2yl-Ethanone-Based Iron Chelators Increase IκB-α Expression, modulate CDK2 and CDK9 activities, and inhibit HIV-1 transcription
Kumari, Namita,Iordanskiy, Sergey,Kovalskyy, Dmytro,Breuer, Denitra,Niu, Xiaomei,Lin, Xionghao,Xu, Min,Gavrilenko, Konstantin,Kashanchi, Fatah,Dhawan, Subhash,Nekhai, Sergei
, p. 6558 - 6571 (2014)
HIV-1 transcription is activated by the Tat protein, which recruits CDK9/cyclin T1 to the HIV-1 promoter. CDK9 is phosphorylated by CDK2, which facilitates formation of the high-molecular-weight positive transcription elongation factor b (P-TEFb) complex. We previously showed that chelation of intracellular iron inhibits CDK2 and CDK9 activities and suppresses HIV-1 transcription, but the mechanism of the inhibition was not understood. In the present study, we tested a set of novel iron chelators for the ability to inhibit HIV-1 transcription and elucidated their mechanism of action. Novel phenyl-1-pyridin-2yl-ethanone (PPY)-based iron chelators were synthesized and examined for their effects on cellular iron, HIV-1 inhibition, and cytotoxicity. Activities of CDK2 and CDK9, expression of CDK9-dependent and CDK2-inhibitory mRNAs, NF-κB expression, and HIV-1- and NF-κB-dependent transcription were determined. PPY-based iron chelators significantly inhibited HIV-1, with minimal cytotoxicity, in cultured and primary cells chronically or acutely infected with HIV-1 subtype B, but they had less of an effect on HIV-1 subtype C. Iron chelators upregulated the expression of IκB-α, with increased accumulation of cytoplasmic NF- κB. The iron chelators inhibited CDK2 activity and reduced the amount of CDK9/cyclin T1 in the large P-TEFb complex. Iron chelators reduced HIV-1 Gag and Env mRNA synthesis but had no effect on HIV-1 reverse transcription. In addition, iron chelators moderately inhibited basal HIV-1 transcription, equally affecting HIV-1 and Sp1- or NF-κB-driven transcription. By virtue of their involvement in targeting several key steps in HIV-1 transcription, these novel iron chelators have the potential for the development of new therapeutics for the treatment of HIV-1 infection.
Catalytic α-Deracemization of Ketones Enabled by Photoredox Deprotonation and Enantioselective Protonation
Chen, Shuming,Gao, Anthony Z.,Ivlev, Sergei I.,Meggers, Eric,Nie, Xin,Ye, Chen-Xi,Zhang, Chenhao
supporting information, p. 13393 - 13400 (2021/09/03)
This study reports the catalytic deracemization of ketones bearing stereocenters in the α-position in a single reaction via deprotonation, followed by enantioselective protonation. The principle of microscopic reversibility, which has previously rendered this strategy elusive, is overcome by a photoredox deprotonation through single electron transfer and subsequent hydrogen atom transfer (HAT). Specifically, the irradiation of racemic pyridylketones in the presence of a single photocatalyst and a tertiary amine provides nonracemic carbonyl compounds with up to 97% enantiomeric excess. The photocatalyst harvests the visible light, induces the redox process, and is responsible for the asymmetric induction, while the amine serves as a single electron donor, HAT reagent, and proton source. This conceptually simple light-driven strategy of coupling a photoredox deprotonation with a stereocontrolled protonation, in conjunction with an enrichment process, serves as a blueprint for other deracemizations of ubiquitous carbonyl compounds.
Site-Selective Pd-Catalyzed C(sp3)?H Arylation of Heteroaromatic Ketones
Kudashev, Anton,Baudoin, Olivier
supporting information, p. 17688 - 17694 (2021/11/16)
A ligand-controlled site-selective C(sp3)?H arylation of heteroaromatic ketones has been developed using Pd catalysis. The reaction occurred selectively at the α- or β-position of the ketone side-chain. The switch from α- to β-arylation was realized by addition of a pyridone ligand. The α-arylation process showed broad scope and high site- and chemoselectivity, whereas the β-arylation was more limited. Mechanistic investigations suggested that α-arylation occurs through C?H activation/oxidative addition/reductive elimination whereas β-arylation involves desaturation and aryl insertion.
Photoenzymatic Hydrogenation of Heteroaromatic Olefins Using ‘Ene’-Reductases with Photoredox Catalysts
Biegasiewicz, Kyle F.,Black, Michael J.,Chung, Megan M.,Hyster, Todd K.,Meichan, Andrew J.,Nakano, Yuji,Sandoval, Braddock A.,Zhu, Tianyu
, p. 10484 - 10488 (2020/04/29)
Flavin-dependent ‘ene’-reductases (EREDs) are highly selective catalysts for the asymmetric reduction of activated alkenes. This function is, however, limited to enones, enoates, and nitroalkenes using the native hydride transfer mechanism. Here we demonstrate that EREDs can reduce vinyl pyridines when irradiated with visible light in the presence of a photoredox catalyst. Experimental evidence suggests the reaction proceeds via a radical mechanism where the vinyl pyridine is reduced to the corresponding neutral benzylic radical in solution. DFT calculations reveal this radical to be “dynamically stable”, suggesting it is sufficiently long-lived to diffuse into the enzyme active site for stereoselective hydrogen atom transfer. This reduction mechanism is distinct from the native one, highlighting the opportunity to expand the synthetic capabilities of existing enzyme platforms by exploiting new mechanistic models.
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.
Octahedral iridium complex catalyzed α-chlorination of 2-acyl imidazoles with tosyl chloride
Deng, Tao,Bora, Pranjal P.,Lin, Shao-Xia,Li, Yi,Kang, Qiang
supporting information, p. 1102 - 1106 (2017/03/02)
An efficient and catalytic α-chlorination of 2-acyl imidazoles with readily available tosyl chloride catalyzed by an octahedral iridium complex under mild condition was reported. A range of 2-acyl imidazoles were converted to their corresponding α-chlorin
A Nitrogen-Assisted One-Pot Heteroaryl Ketone Synthesis from Carboxylic Acids and Heteroaryl Halides
Demkiw, Krystyna,Araki, Hirofumi,Elliott, Eric L.,Franklin, Christopher L.,Fukuzumi, Yoonjoo,Hicks, Frederick,Hosoi, Kazushi,Hukui, Tadashi,Ishimaru, Yoichiro,O'Brien, Erin,Omori, Yoshimasa,Mineno, Masahiro,Mizufune, Hideya,Sawada, Naotaka,Sawai, Yasuhiro,Zhu, Lei
, p. 3447 - 3456 (2016/05/19)
A practical and highly effective one-pot synthesis of versatile heteroaryl ketones directly from carboxylic acids and heteroaryl halides under mild conditions is reported. This method does not require derivatization of carboxylic acids (preparation of acid chlorides, Weinreb amides, etc.) or the use of any additives/catalysts. A wide substrate scope of carboxylic acids with high functional group tolerance has also been demonstrated. The results reveal that the presence of an α-nitrogen on the halide substrate greatly improves the desired ketone formation.
Enantioselective, catalytic trichloromethylation through visible-light-activated photoredox catalysis with a chiral iridium complex
Huo, Haohua,Wang, Chuanyong,Harms, Klaus,Meggers, Eric
supporting information, p. 9551 - 9554 (2015/08/18)
An enantioselective, catalytic trichloromethylation of 2-acyl imidazoles and 2-acylpyridines is reported. Several products are formed with enantiomeric excess of ≥99%. In this system, a chiral iridium complex serves a dual function, as a catalytically active chiral Lewis acid and simultaneously as a precursor for an in situ assembled visible-light-triggered photoredox catalyst.
Rhodium Catalyzed Asymmetric Hydrogenation of 2-Pyridine Ketones
Yang, Hailong,Huo, Ningning,Yang, Ping,Pei, Hao,Lv, Hui,Zhang, Xumu
supporting information, p. 4144 - 4147 (2015/09/15)
Catalyzed by [Rh(COD)Binapine]BF4, the asymmetric hydrogenation of 2-pyridine ketones has been achieved with excellent enantioselectivities (enantiomeric excesses up to 99%) under mild conditions. This method is suitable for various kinds of 2-pyridine ketones and their derivatives. A number of enantiomerically pure chiral 2-pyridine-aryl/alkyl alcohols were prepared through hydrogenation, which can be used directly in organic synthesis.
Sp3C-H bond alkylation of ketones with alkenes via ruthenium(ii) catalysed dehydrogenation of alcohols
Li, Bin,Darcel, Christophe,Dixneuf, Pierre H.
supporting information, p. 5970 - 5972 (2014/05/20)
The sp3C-H bond functionalisation of 2-pyridyl ethanols upon reaction with alkenes, in the presence of a [RuCl2(arene)] 2 catalyst and Cu(OAc)2·H2O, is performed under mild conditions without additional base. This reaction proceeds via a tandem alcohol dehydrogenation/alkylation with alkenes of the resulting ketone at its α sp3C-H bond. the Partner Organisations 2014.
