63072-15-1Relevant academic research and scientific papers
Binuclear and polymeric Hg(II) complexes of an ambidentate phosphorus ylide: Synthesis, crystal structure, antibacterial activity, and theoretical studies
Sabounchei, Seyyed Javad,Kazemi Andalib, Faeze,Hosseinzadeh, Marjan,Sedghi, Asieh,Hashemi, Ali,Karamian, Roya,Van Hecke, Kristof
, (2020)
The new α-keto-stabilized phosphorus ylide Ph3PCHC(O)PhCN (Y) was synthesized by addition of triphenylphosphine to 2-bromo-4′-cyanoacetophenone, followed by treatment with NaOH 10%. Reaction of ligand (Y) with methanolic solution of mercury(II)
Ground-State Electron Transfer as an Initiation Mechanism for Biocatalytic C-C Bond Forming Reactions
Fu, Haigen,Lam, Heather,Emmanuel, Megan A.,Kim, Ji Hye,Sandoval, Braddock A.,Hyster, Todd K.
, p. 9622 - 9629 (2021/07/01)
The development of non-natural reaction mechanisms is an attractive strategy for expanding the synthetic capabilities of substrate promiscuous enzymes. Here, we report an "ene"-reductase catalyzed asymmetric hydroalkylation of olefins using α-bromoketones as radical precursors. Radical initiation occurs via ground-state electron transfer from the flavin cofactor located within the enzyme active site, an underrepresented mechanism in flavin biocatalysis. Four rounds of site saturation mutagenesis were used to access a variant of the "ene"-reductase nicotinamide-dependent cyclohexanone reductase (NCR) from Zymomonas mobiles capable of catalyzing a cyclization to furnish β-chiral cyclopentanones with high levels of enantioselectivity. Additionally, wild-type NCR can catalyze intermolecular couplings with precise stereochemical control over the radical termination step. This report highlights the utility for ground-state electron transfers to enable non-natural biocatalytic C-C bond forming reactions.
Copper-Catalyzed N-O Cleavage of α,β-Unsaturated Ketoxime Acetates toward Structurally Diverse Pyridines
Ding, Xiaojuan,Duan, Jindian,Fang, Zheng,Guo, Kai,Li, Zhenjiang,Mao, Yiyang,Rong, Binsen,Xu, Gaochen,Zhang, Lei,Zhu, Ning
supporting information, p. 2532 - 2542 (2020/03/13)
The copper-catalyzed [4 + 2] annulation of α,β-unsaturated ketoxime acetates with 1,3-dicarbonyl compounds for the synthesis of three classes of structurally diverse pyridines has been developed. This method employs 1,3-dicarbonyl compounds as C2 synthons and enables the synthesis of multifunctionalized pyridines with diverse electron-withdrawing groups in moderate to good yields. The mechanistic investigation suggests that the reactions proceed through an ionic pathway.
Tandem Wittig Reaction-Ring Contraction of Cyclobutanes: A Route to Functionalized Cyclopropanecarbaldehydes
Aitken, David J.,Caboni, Pierluigi,Cuccu, Federico,Frongia, Angelo,Luridiana, Alberto,Secci, Francesco,Serusi, Lorenzo
supporting information, (2019/10/08)
An original tandem reaction consisting of a Wittig reaction-ring contraction process between α-hydroxycyclobutanone and phosphonium ylides has been developed. Highly functionalized cyclopropanecarbaldehydes are obtained in good to high yield.
Catalytic Cyclooligomerization of Enones with Three Methylene Equivalents
Farley, Conner M.,Zhou, You-Yun,Banka, Nishit,Uyeda, Christopher
, p. 12710 - 12714 (2018/10/09)
Cyclic structures are highly represented in organic molecules, motivating a wealth of catalytic methods targeting their synthesis. Among the various ring-forming processes, cyclooligomerization reactions possess several attractive features but require addressing a unique challenge associated with controlling ring-size selectivity. Here we describe the catalytic reductive cocyclooligomerization of an enone and three carbene equivalents to generate a cyclopentane, a process that constitutes a formal [2 + 1 + 1 + 1]-cycloaddition. The reaction is promoted by a (quinox)Ni catalyst and uses CH2Cl2/Zn as the C1 component. Mechanistic studies are consistent with a metallacycle-based pathway, featuring sequential migratory insertions of multiple carbene equivalents to yield cycloalkanes larger than cyclopropanes.
Nonenzymatic Dynamic Kinetic Resolution of in situ Generated Hemithioacetals: Access to 1,3-Disubstituted Phthalans
Nath, Utpal,Chowdhury, Deepan,Pan, Subhas Chandra
, p. 1628 - 1633 (2018/03/21)
The first nonenzymatic DKR reaction of hemithioacetals is developed. Hemithioacetals were formed in situ via thiol addition and subsequently underwent an intramolecular oxa-Michael reaction. The scope of the reaction was quite broad ranging from aliphatic to aromatic substituents and 1,3-disubstituted-1,3-dihyroisobenzofuran products were obtained in good yields with moderate diastereoselectivities and high enantioselectivities. (Figure presented.).
Novel hybrids derived from aspirin and chalcones potently suppress colorectal cancer in vitro and in vivo
Lu, Shan,Obianom, Obinna N.,Ai, Yong
, p. 1722 - 1732 (2018/10/26)
Colorectal cancer (CRC) remains the fourth leading cause of cancer deaths around the world despite the availability of many approved small molecules for treatment. The issues lie in the potency, selectivity and targeting of these compounds. Therefore, new
Synthesis of trifluoromethyl-/cyclopropyl-substituted 2-isoxazolines by DBU-promoted domino reaction
Liu, Xiao-Dong,Ma, Hai-Yan,Xing, Chun-Hui,Lu, Long
, p. 1780 - 1783 (2017/07/27)
NTrifluoromethyl and cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5- trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method could also apply to other trifluoromethyl-substituted enones.
Enantioselective Organocatalytic Cascade Approach to Different Classes of Benzofused Acetals
Paz, Bruno Matos,Klier, Lydia,N?sborg, Line,Lauridsen, Vibeke Henriette,Jensen, Frank,J?rgensen, Karl Anker
, p. 16810 - 16818 (2016/11/16)
A novel enantioselective organocatalytic strategy is presented for the synthesis of tetrahydrofurobenzofuran and methanobenzodioxepine natural product core structures. The strategy is based on a pair of divergent reaction pathways in which hydroxyarenes react with γ-keto-α,β-unsaturated aldehydes, catalyzed by a chiral secondary amine. One reaction pathway, which leads to chiral 5,5-fused acetals with two stereocenters—the tetrahydrofurobenzofuran scaffolds—proceeds in moderate yields and up to 96 % ee. The other reaction pathway provides 5,6-bridged methanobenzodioxepine scaffolds with three stereocenters in moderate to good yields and up to 95 % ee. The reaction is remarkable as it can proceed with catalyst loadings as low as 0.25 mol %, providing one of the highest known turnover numbers in iminium ion catalysis. Furthermore, the hemiacetal tetrahydrofurobenzofuran can undergo functionalizations including reduction, oxidation, and allylation. Finally, the effects involved in the substrate control for the divergent pathways, based on both experimental and computational studies, have been investigated. A model involving steric, electronic and stereoelectronic interactions is discussed to rationalize the observed selectivities.
Identification of novel chromenone derivatives as interleukin-5 inhibitors
Venkateswararao, Eeda,Kim, Min-Seok,Sharma, Vinay K.,Lee, Ki-Cheul,Subramanian, Santhosh,Roh, Eunmiri,Kim, Youngsoo,Jung, Sang-Hun
, p. 31 - 38 (2013/03/13)
A series of (E)-5-alkoxy-3-(3-phenyl-3-oxoprop-1-enyl)-4H-chromen-4-ones (4) and (E)-5-alkoxy-3-(3-hydroxy-3-phenylprop-1-enyl)-4H-chromen-4-ones (5) were synthesized and evaluated for their IL-5 inhibitory activity. Propenone analogs 4 possess some of the structurally important characteristics of isoflavone 2 and chalcone 3 previously known as potent IL-5 inhibitor. However, the inhibitory activity of 4 was weak and therefore this structural hybridization appears to be ineffective for the design of IL-5 inhibitor. Meanwhile the potent activity profile of compounds 5 was discovered. This enhanced activity of 5 compared to 4 could be due to the effective location of hydroxyl group of allylic alcohol moiety of 5 in the 3D structure. The electron withdrawing substituents at position 4 of phenyl ring of 5 enhances the activity possibly due to an increase in the strength of hydrogen bonding property of hydroxyl group of allylic alcohol moiety.
