3618-37-9Relevant academic research and scientific papers
Macrolide Synthesis through Intramolecular Oxidative Cross-Coupling of Alkenes
Jiang, Bing,Zhao, Meng,Li, Shu-Sen,Xu, Yun-He,Loh, Teck-Peng
supporting information, p. 555 - 559 (2018/02/21)
A RhIII-catalyzed intramolecular oxidative cross-coupling between double bonds for the synthesis of macrolides is described. Under the optimized reaction conditions, macrocycles containing a diene moiety can be formed in reasonable yields and with excellent chemo- and stereoselectivity. This method provides an efficient approach to synthesize macrocyclic compounds containing a 1,3-conjugated diene structure.
Bifunctional ligands for Pd-catalyzed selective alkoxycarbonylation of alkynes
Qi, Huimin,Huang, Zijun,Wang, Menglan,Yang, Peiju,Du, Chen-Xia,Chen, Shu-Wei,Li, Yuehui
, p. 63 - 68 (2018/05/04)
Catalytic carbonylations of alkynes represent straightforward and atom-economic synthesis of α,β-unsaturated carbonyl compounds. One of the issues associated with the currently known catalytic systems is insufficient efficiency. In this context, Pd/ligand-catalyzed regioselective and efficient alkoxycarbonylation of terminal alkynes is desirable for the synthesis of α,β-unsaturated esters. Herein, we present the use of a newly designed bifunctional ligand for efficient Pd-catalyzed alkoxycarbonylation of alkynes. Both aliphatic and aromatic alkynes were smoothly transformed to the branched desired products with high selectivity (28 examples, 45–96% yields, 95.0–99.9% selectivity).
Rh(I)-bisphosphine-catalyzed asymmetric, intermolecular hydroheteroarylation of α-substituted acrylate derivatives
Filloux, Claire M.,Rovis, Tomislav
supporting information, p. 508 - 517 (2015/01/30)
Asymmetric hydroheteroarylation of alkenes represents a convenient entry to elaborated heterocyclic motifs. While chiral acids are known to mediate asymmetric addition of electron-rich heteroarenes to Michael acceptors, very few methods exploit transition metals to catalyze alkylation of heterocycles with olefins via a C-H activation, migratory insertion sequence. Herein, we describe the development of an asymmetric, intermolecular hydroheteroarylation reaction of α-substituted acrylates with benzoxazoles. The reaction provides 2-substitued benzoxazoles in moderate to excellent yields and good to excellent enantioselectivities. Notably, a series of mechanistic studies appears to contradict a pathway involving enantioselective protonation of a Rh(I)-enolate, despite the fact that such a mechanism is invoked almost unanimously in the related addition of aryl boronic acids to methacrylate derivatives. Evidence suggests instead that migratory insertion or beta-hydride elimination is enantiodetermining and that isomerization of a Rh(I)-enolate to a Rh(I)-heterobenzyl species insulates the resultant α-stereocenter from epimerization. A bulky ligand, CTH-(R)-Xylyl-P-Phos, is crucial for reactivity and enantioselectivity, as it likely discourages undesired ligation of benzoxazole substrates or intermediates to on- or off-cycle rhodium complexes and attenuates coordination-promoted product epimerization.
Design, synthesis and antibacterial activity of novel N-formylhydroxylamine derivatives as PDF inhibitors
Yin,Jia,Zhao,Xu,Tang,Wang
experimental part, p. 695 - 703 (2011/07/29)
A new series of N-formylhydroxylamines 11a-i have been synthesized through a multi-step protocol starting from diethyl malonate. These compounds have been structurally characterized by IR, 1H NMR and HRMS. All the synthesized compounds 11a-i have been screened for antibacterial activities. All the compounds are found to exhibit potent in vitro inhibitory activity against Staphylococcus aureus and relatively weak antibacterial activity against Klebsiella pneumoniae.
Synthesis and antimicrobial activities of novel peptide deformylase inhibitors
Yin, Ling,Xu, Wei-Ren,Wang, Zhi-Guo,Zhang, Da-Tong,Jia, Jiong,Ge, Yan-Qing,Li, Yan,Wang, Jian-Wu
experimental part, p. 196 - 205 (2010/10/19)
A new series of N-formylhydroxylamine compounds were designed, optimized with the AutoDock 4.0.1to investigate the interactions between the target compounds and the amino acid residues of the Escherichia coli PDF?Ni enzyme, and then synthesized through mu
Isoxazoline derivative and a process for the preparation thereof
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Page/Page column 40, (2010/02/07)
The present invention provides to an isoxazoline derivative of formula (I), the pharmaceutically acceptable salts, esters and stereochemically isomeric forms thereof, and the use of the derivative in inhibiting the activity of caspases. The present invent
Nitration of α,β-unsaturated esters. Evidence for positive charge build-up adjacent to carbonyl carbon
Hewlins, Stuart A.,Murphy, John A.,Lin, Jian,Hibbs, David E.,Hursthouse, Michael B.
, p. 1559 - 1570 (2007/10/03)
Reactive intermediates formed in the nitration of certain α,β-unsaturated esters with nitronium tetrafluoroborate exhibit behaviour expected of highly reactive α-carbonyl cations. Three diagnostic reaction types have been observed which indicate the presence of these destabilised cations: (i) trapping in a Ritter reaction, (ii) cyclopropane formation from propyl cations, (iii) Wagner-Meerwein migration of alkyl groups. Semi-empirical calculations of the relative gas-phase stabilities of the proposed intermediate cations are useful in rationalising the observed chemistry.
Enantioselective hydrogenation of α,β-unsaturated acids. Substrate-modifier interaction over cinchonidine modified Pd/Al2O3
Borszeky,Mallat,Baiker
, p. 3745 - 3753 (2007/10/03)
X-Ray diffraction, IR measurements and catalytic hydrogenation of various substituted acrylic acids in apolar solvents, as well as molecular modelling provide new insight into the nature of the cinchonidine-substrate interaction and a general rule to predict the major enantiomer.
Kinetics and Mechanism of Oxidative Alkoxylation of Unsaturated Aldehydes
Kuptsevich,Pikh
, p. 781 - 783 (2007/10/03)
Kinetic trends and mechanism of catalytic oxidation of unsaturated aldehydes with hydrogen peroxide in alcohols was studied. The participation of semiacetals of unsaturated aldehydes in the formation of reaction products is established and the dependence
Preparation et etude de nouveaux derives organozinciques allyliques fonctionnels
Lambert, Francois,Kirschleger, Bernard,Villieras, Jean
, p. 273 - 286 (2007/10/02)
Stable organozinc compounds derived from alkyl-3-alkyl-2-(bromomethyl)-propenoates have been prepared.NMR 13C, 1H and IR studies show only one Z stereoisomer (no methylenic form) with a strong chelation between zinc and the carbonyl oxygen of the ester and solvated by only one solvent molecule.Hydrolysis can be achieved by two concurrent mechanisms with or without transposition.
