451466-81-2Relevant articles and documents
Enantiomerically Pure Quinoline-Based κ-Opioid Receptor Agonists: Chemoenzymatic Synthesis and Pharmacological Evaluation
Martin, Benedikt,Schepmann, Dirk,Bernal, Freddy A.,Schmidt, Thomas J.,Che, Tao,Loser, Karin,Wünsch, Bernhard
, p. 1408 - 1420 (2020/07/06)
Racemic K-opioid receptor (KOR) agonist 2-(3,4-dichlorophenyl)-1-[(4aRS,8SR,8aSR)-8-(pyrrolidin-1-yl)-3,4,4a,5,6,7,8,8a-octahydroquinolin-1(2H)-yl]ethan-1-one ((±)-4) was prepared in a diastereoselective synthesis. The first key step of the synthesis was the diastereoselective hydrogenation of the silyl ether of 1,2,3,4-tetrahydroquinoin-8-ol ((±)-9) to afford cis,cis-configured perhydroquinoline derivative (±)-10. Removal of the TBDMS protecting group led to a β-aminoalcohol that reacted with SO2Cl2 to form an oxathiazolidine. Nucleophilic substitution with pyrrolidine resulted in the desired cis,trans-configured perhydroquinoline upon inversion of the configuration. In order to obtain enantiomerically pure KOR agonists 4 (99.8 % ee) and ent-4 (99.0 % ee), 1,2,3,4-tetrahydroquinolin-8-ols (R)-8 (99.1 % ee) and (S)-8 (98.4 % ee) were resolved by an enantioselective acetylation catalyzed by Amano lipase PS-IM. The absolute configuration was determined by CD spectroscopy. The 4aR,8S,8aS-configured enantiomer 4 showed sub-nanomolar KOR affinity (Ki=0.81 nM), which is more than 200 times higher than the KOR affinity of its enantiomer ent-4. In the cAMP assay and the Tango β-arrestin-2 recruitment assay, 4 behaved as a KOR agonist. Upon incubation of human macrophages, human dendritic cells, and mouse myeloid immune cells with 4, the number of cells expressing co-stimulatory receptor CD86 and proinflammatory cytokines interleukin 6 and tumor necrosis factor α was significantly reduced; this indicates the strong anti-inflammatory activity of 4. The anti-inflammatory effects correlated well with the KOR affinity: (4aR,8S,8aS)-4 was slightly more potent than the racemic mixture (±)-4, and the distomer ent-4 was almost inactive.
Chiral amino-pyridine-phosphine tridentate ligand, manganese complex, and preparation method and application thereof
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Paragraph 0597-0600; 0605, (2020/07/13)
The invention discloses a chiral amino-pyridine-phosphine tridentate ligand, a manganese complex, and a preparation method and application thereof. The chiral amino-pyridine-phosphine tridentate ligand is shown as a formula II, and the manganese complex of the chiral amino-pyridine-phosphine tridentate ligand can be used for efficiently catalyzing and hydrogenating ketone compounds to prepare chiral alcohol compounds in a high enantioselectivity mode. The chiral amino-pyridine-phosphine tridentate ligand and the manganese complex are simple in synthesis process, good in stability, high in catalytic activity and mild in reaction conditions.
Lutidine-Based Chiral Pincer Manganese Catalysts for Enantioselective Hydrogenation of Ketones
Zhang, Linli,Tang, Yitian,Han, Zhaobin,Ding, Kuiling
supporting information, p. 4973 - 4977 (2019/03/17)
A series of MnI complexes containing lutidine-based chiral pincer ligands with modular and tunable structures has been developed. The complex shows unprecedentedly high activities (up to 9800 TON; TON=turnover number), broad substrate scope (81 examples), good functional-group tolerance, and excellent enantioselectivities (85–98 % ee) in the hydrogenation of various ketones. These aspects are rare in earth-abundant metal catalyzed hydrogenations. The utility of the protocol have been demonstrated in the asymmetric synthesis of a variety of key intermediates for chiral drugs. Preliminary mechanistic investigations indicate that an outer-sphere mode of substrate–catalyst interactions probably dominates the catalysis.
Asymmetric Hydroboration of Heteroaryl Ketones by Aluminum Catalysis
Lebedev, Yury,Polishchuk, Iuliia,Maity, Bholanath,Dinis Veloso Guerreiro, Miguel,Cavallo, Luigi,Rueping, Magnus
supporting information, p. 19415 - 19423 (2019/12/24)
A series of methyl aluminum complexes bearing chiral biphenol-type ligands were found to be highly active catalysts in the asymmetric reduction of heterocyclic ketones (S/C = 100-500, ee up to 99%). The protocol is suitable for a wide range of substrates and has a high tolerance to functional groups. The formed 2-heterocyclic-alcohols are valuable building blocks in drug discovery or can be used as ligands in asymmetric catalysis. Isolation and comprehensive characterization of the reaction intermediates support a catalysis cycle proposed by DFT calculations.
Iridium/f-Amphol-catalyzed Efficient Asymmetric Hydrogenation of Benzo-fused Cyclic Ketones
Yin, Congcong,Dong, Xiu-Qin,Zhang, Xumu
supporting information, p. 4319 - 4324 (2018/10/15)
Iridium/f-Amphol-catalyzed asymmetric hydrogenation of various benzo-fused five to seven-membered cyclic ketones was successfully developed, affording a series of chiral benzo-fused cyclic alcohols with excellent results (75%–99% yields, 93%–>99% ee, and TON up to 297 000). The enantioenriched products can be employed as key intermediates or motifs for the synthesis of some important biologically active compounds, such as rasagiline mesylate TVP-1012 used for the treatment of Parkinson's disease, the enantiomer of anticonvulsant drug eslicarbazepine acetate (BIA 2-093). (Figure presented.).
Catalytic asymmetric hydrogenation of quinoline carbocycles: Unusual chemoselectivity in the hydrogenation of quinolines
Kuwano, Ryoichi,Ikeda, Ryuhei,Hirasada, Kazuki
supporting information, p. 7558 - 7561 (2015/05/04)
The reduction of quinolines selectively took place on their carbocyclic rings to give 5,6,7,8-tetrahydroquinolines, when the hydrogenation was conducted in the presence of a Ru(η3-methallyl)2(cod)-PhTRAP catalyst. The chiral ruthenium catalyst converted 8-substituted quinolines into chiral 5,6,7,8-tetrahydroquinolines with up to 91:9 er. This journal is
Iron(ii)-bis(isonitrile) complexes: Novel catalysts in asymmetric transfer hydrogenations of aromatic and heteroaromatic ketones
Naik, Anu,Maji, Tapan,Reiser, Oliver
supporting information; experimental part, p. 4475 - 4477 (2010/11/03)
Chiral iron(ii)-bis(isonitrile) complexes catalyse the transfer hydrogenation of aromatic ketones with enantioselectivities up to 91% ee, most likely via hydride transfer through imine intermediates, generated by in situ reduction of the isonitrile ligands, whereas iron acts as a Lewis acid to activate the ketone.
Iridium catalysts with bicyclic pyridine-phosphinite ligands: Asymmetric hydrogenation of olefins and furan derivatives
Kaiser, Stefan,Smidt, Sebastian P.,Pfaltz, Andreas
, p. 5194 - 5197 (2007/10/03)
(Chemical Equation Presented) Superior bicyclics: Iridium catalysts as 1 derived from pyridine-phosphinite ligands considerably extend the scope of asymmetric hydrogenation. In addition to various unfunctionalized and functionalized olefins, furans, and benzofurans, for which no catalysts were known before, are also hydrogenated with high enantioselectivity (see scheme).
Synthesis of enantiomerically pure 8-substituted 5,6,7,8-tetrahydro quinolines
Uenishi, Junichi,Hamada, Masahiro
, p. 625 - 630 (2007/10/03)
Enantiomerically pure (S)-5,6,7,8-tetrahydroquinolin-8-ol [(S)-1] and (R)-8-acetoxy-5,6,7,8-tetrahydroquinoline [(R)-2] have been prepared by the lipase-catalyzed kinetic acetylation of racemic 5,6,7,8-tetrahydroquinolin-8-ol [(±)-1] in excellent chemical
