108714-18-7Relevant academic research and scientific papers
Rh(II)/Br?nsted acid cocatalyzed intramolecular trapping of ammonium ylides with enones: Diastereoselective synthesis of 2,2,3-trisubstituted indolines
Jiang, Liqin,Xu, Renqi,Kang, Zhenghui,Feng, Yixiao,Sun, Fengxia,Hu, Wenhao
, p. 8440 - 8446 (2014)
Highly diastereoselective intramolecular trapping of ammonium ylides with enones has been developed through a Rh(II)/Br?nsted acid cocatalytic strategy. This process allows rapid and efficient construction of N-unprotected polyfunctional 2,2,3-trisubstitu
Enantioselective Rauhut–Currier Reaction with β-Substituted Acrylamides Catalyzed by N-Heterocyclic Carbenes
Pitchumani, Venkatachalam,Breugst, Martin,Lupton, David W.
, p. 9413 - 9418 (2021/12/09)
β-Substituted acrylamides have low electrophilicity and are yet to be exploited in the enantioselective Rauhut–Currier reaction. By exploiting electron-withdrawing protection of the amide and moderate nucleophilicity N-heterocyclic carbenes, such substrates have been converted to enantioenriched quinolones. The reaction proceeds with complete diastereoselectivity, good yield, and modest enantioselectivity. Derivatizations are reported, as are computational studies, supporting decreased amide bond character with electron-withdrawing protection of the nitrogen.
Diastereoselective Synthesis of Tetracyclic Tetrahydroquinoline Derivative Enabled by Multicomponent Reaction of Isocyanide, Allenoate, and 2-Aminochalcone
Wang, Zhishuang,Fei, Youwen,Tang, Chongrong,Cui, Lei,Shen, Jie,Yin, Kun,Lu, Shanya,Li, Jian
supporting information, p. 4094 - 4098 (2021/05/26)
We report here a multicomponent protocol to assemble several polycyclic dihydropyran-fused tetrahydroquinoline structures with excellent diastereoselectivity. This procedure employs simple feedstocks to accomplish a series of diverse structures, which is
Design and synthesis of novel anti-inflammatory/anti-ulcer hybrid molecules with antioxidant activity
Balaini, Ajitesh,Bali, Alka,Chaudhari, Bhim Bahadur
, p. 994 - 1006 (2021/11/30)
Background: NSAIDs are the most widely prescribed medications worldwide for their anti-inflammatory, antipyretic, and analgesic effects. However, their chronic use can lead to several adverse drug events including GI toxicity. The selective COX-2 inhibitors developed as gastro-sparing NSAIDs also suffer from serious adverse effects which limit their efficacy. Objective: Local generation of reactive oxygen species is implicated in NSAID-mediated gastric ul-ceration and their combination with H2 antagonists like famotidine reduces the risk of ulcers. The objective of this work was to design and synthesize novel methanesulphonamido isoxazole derivatives by hybridizing the structural features of NSAIDs with those of antiulcer drugs (ranitidine, fa-motidine, etc.) to utilize a dual combination of anti-inflammatory activity and reducing (antioxidant) potential. Methods: The designing process utilized three dimensional similarity studies and utilized an isoxa-zole core having a potential for anti-inflammatory as well as radical scavenging antioxidant activity. The compounds were assayed for their anti-inflammatory activity in established in vivo models. The in vitro antioxidant activity was assessed in potassium ferricyanide reducing power (PFRAP) assay employing ascorbic acid as the standard drug. Results: Compounds 5, 6, 9 and 10 showed anti-inflammatory activity comparable to the standard drugs and were also found to be non-ulcerogenic at the test doses. Compounds 6-10 exhibited good antioxidant effect in the concentration range of 1.0-50.0 μmol/ml. The test compounds were also found to comply with the Lipinski rule suggesting good oral absorption. Conclusion: A new series of isoxazole based compounds is being reported with good anti-inflammatory activity coupled with antioxidant potential as gastro-sparing anti-inflammatory agents.
Superbase-Mediated Indirect Friedl?nder Reaction: A Transition Metal-Free Oxidative Annulation toward Functionalized Quinolines
Rahul,Nitha,Omanakuttan, Vishnu K.,Babu, Sheba Ann,Sasikumar,Praveen, Vakayil K.,Hopf, Henning,John, Jubi
, p. 3081 - 3089 (2020/05/08)
A superbase mediated indirect Friedl?nder reaction towards functionalized quinolines has been realized. The reaction was performed with o-aminobenzyl alcohol and ketones having an active methylene moiety in the presence of KOH and in DMSO. The reaction proceeds predominantly via initial formation of an imine intermediate and subsequent oxidation of the benzyl alcohol functionality and condensation to afford substituted quinolines. We could also demonstrate that a minor fraction of the reaction proceeds via a chalcone intermediate. The transition metal-free oxidative annulation was found to be general affording 2-substituted, 2,3-disubstituted/fused or multi-substituted quinolines. The reaction was extended towards the functionalization of natural products and the applicability of the reaction for gram-scale synthesis of quinolines was also demonstrated.
Visible-light driven synthesis of polycyclic benzo[: D] [1,3]oxazocine from 2-aminochalcone
Chen, Junhan,Gao, Yu-Qi,He, Yu-Peng,Hou, Yi,Li, Ruoxin,Xie, Weiqing,Zhang, Sheng-Yong,Zhu, Liming
supporting information, p. 6739 - 6742 (2020/07/13)
Herein, we report a tandem cycloisomerization/nucleophilic addition/cyclization of 2-amino chalcone with bifunctional nucleophiles driven by visible light. This cascade process is realized by the irradiation of a blue LED at room temperature, which provides a concise route to structurally diverse benzo[d][1,3]oxazocine scaffolds. Mechanistic studies show that the reaction is initiated with the E to Z isomerization of a C-C double bond upon the irradiation of visible light, followed by cyclization/rearomatization to generate a transient quinolinium intermediate, which is trapped by the nucleophile and cyclized to produce the polycyclic benzo[d][1,3]oxazocine.
Homogeneous Nickel-Catalyzed Sustainable Synthesis of Quinoline and Quinoxaline under Aerobic Conditions
Bains, Amreen K.,Singh, Vikramjeet,Adhikari, Debashis
supporting information, p. 14971 - 14979 (2020/11/30)
Dehydrogenative coupling-based reactions have emerged as an efficient route toward the synthesis of a plethora of heterocyclic rings. Herein, we report an efficacious, nickel-catalyzed synthesis of two important heterocycles such as quinoline and quinoxaline. The catalyst is molecularly defined, is phosphine-free, and can operate at a mild reaction temperature of 80 °C. Both the heterocycles can be easily assembled via double dehydrogenative coupling, starting from 2-aminobenzyl alcohol/1-phenylethanol and diamine/diol, respectively, in a shorter span of reaction time. This environmentally benign synthetic protocol employing an inexpensive catalyst can rival many other transition-metal systems that have been developed for the fabrication of two putative heterocycles. Mechanistically, the dehydrogenation of secondary alcohol follows clean pseudo-first-order kinetics and exhibits a sizable kinetic isotope effect. Intriguingly, this catalyst provides an example of storing the trapped hydrogen in the ligand backbone, avoiding metal-hydride formation. Easy regeneration of the oxidized form of the catalyst under aerobic/O2 oxidation makes this protocol eco-friendly and easy to handle.
Continuous Flow Synthesis of Quinolines via a Scalable Tandem Photoisomerization-Cyclization Process
Di Filippo, Mara,Baumann, Marcus
, p. 6199 - 6211 (2020/08/26)
A continuous photochemical process is presented that renders a series of quinoline products via an alkene isomerization and cyclocondensation cascade. It is demonstrated that a high-power LED lamp generates the desired targets with higher productivity and efficiency than a medium-pressure Hg-lamp. The scope of this tandem process is established and allows for the generation of various substituted quinolines in high yields and with throughputs of greater than one gram per hour. Finally, this effective flow process is coupled with a telescoped hydrogenation reaction to render a series of tetrahydroquinolines including the antimalarial natural product galipinine.
Enantioselective Synthesis of Tetrahydroquinolines via One-Pot Cascade Biomimetic Reduction?
Zhao, Zi-Biao,Li, Xiang,Chen, Mu-Wang,Wu, Bo,Zhou, Yong-Gui
supporting information, p. 1691 - 1695 (2020/11/03)
A novel and efficient protocol for the synthesis of chiral tetrahydroquinoline derivatives with excellent enantioselectivities and high yields has been developed through one-pot cascade biomimetic reduction. The detailed reaction pathway includes the acid-catalyzed and ruthenium-catalyzed formation of aromatic quinoline intermediates and biomimetic asymmetric reduction.
Ultraspecific live imaging of the dynamics of zebrafish neutrophil granules by a histopermeable fluorogenic benzochalcone probe
Colucci-Guyon, Emma,Batista, Ariane S.,Oliveira, Suellen D. S.,Blaud, Magali,Bellettini, Ismael C.,Marteyn, Benoit S.,Leblanc, Karine,Herbomel, Philippe,Duval, Romain
, p. 3654 - 3670 (2019/03/28)
Neutrophil granules (NGs) are key components of the innate immune response and mark the development of neutrophilic granulocytes in mammals. However, there has been no specific fluorescent vital stain up to now to monitor their dynamics within a whole live organism. We rationally designed a benzochalcone fluorescent probe (HAB) featuring high tissue permeability and optimal photophysics such as elevated quantum yield, pronounced solvatochromism and target-induced fluorogenesis. Phenotypic screening identified HAB as the first cell- and organelle-specific small-molecule fluorescent tracer of NGs in live zebrafish larvae, with no labeling of other cell types or organelles. HAB staining was independent of the state of neutrophil activation, labeling NGs of both resting and phagocytically active neutrophils with equal specificity. By high-resolution live imaging, we documented the dynamics of HAB-stained NGs during phagocytosis. Upon zymosan injection, labeled NGs were rapidly recruited to the forming phagosomes. Despite being a reversible ligand, HAB could not be displaced by high concentrations of pharmacologically relevant competing chalcones, indicating that this specific labeling was the result of the HAB's precise physicochemical signature rather than a general feature of chalcones. However, one of the competitors was discovered as a promising interstitial fluorescent tracer illuminating zebrafish histology, similarly to BODIPY-ceramide. As a yellow-emitting histopermeable vital stain, HAB functionally and spectrally complements most genetically incorporated fluorescent tags commonly used in live zebrafish biology, holding promise for the study of neutrophil-dependent responses relevant to human physiopathology such as developmental defects, inflammation and infection. Furthermore, HAB intensely labeled isolated live human neutrophils at the level of granulated subcellular structures consistent with human NGs, suggesting that the labeling of NGs by HAB is not restricted to the zebrafish model but also relevant to mammalian systems.
