583-02-8Relevant articles and documents
CARBON-13 SUBSTITUENT CHEMICAL SHIFTS IN THE SIDE-CHAIN CARBONS OF AROMATIC SYSTEMS: THE IMPORTANCE OF Π-POLARIZATION IN DETERMINING CHEMICAL SHIFTS
Bromilow, John,Brownlee, Robert T. C.,Craik, David J.,Fiske, Peter R.,Rowe, Jeffrey E.,Sadek, Maruse
, p. 753 - 759 (1981)
13C substituent chemical shifts of the carbonyl sites in the side-chains of meta- and para-substituted benzenes of the type XC6H4COZ have been measured.Analysis of this data using the dual substituent parameter method shows that inductive effeccts are predominant.The reverse inductive contribution observed is explained in therms of a Π-polarization mechanism.Critical support for this mechanism is obtained from additional series where the carbonyl is complexed with Lewis acids.The concepts of 'extended' and 'localized' Π-polarization are discussed.
A Bifunctional Copper Catalyst Enables Ester Reduction with H2: Expanding the Reactivity Space of Nucleophilic Copper Hydrides
Kaicharla, Trinadh,Ngoc, Trung Tran,Teichert, Johannes F.,Tzaras, Dimitrios-Ioannis,Zimmermann, Birte M.
supporting information, p. 16865 - 16873 (2021/10/20)
Employing a bifunctional catalyst based on a copper(I)/NHC complex and a guanidine organocatalyst, catalytic ester reductions to alcohols with H2 as terminal reducing agent are facilitated. The approach taken here enables the simultaneous activation of esters through hydrogen bonding and formation of nucleophilic copper(I) hydrides from H2, resulting in a catalytic hydride transfer to esters. The reduction step is further facilitated by a proton shuttle mediated by the guanidinium subunit. This bifunctional approach to ester reductions for the first time shifts the reactivity of generally considered "soft"copper(I) hydrides to previously unreactive "hard"ester electrophiles and paves the way for a replacement of stoichiometric reducing agents by a catalyst and H2.
Pleuromutilin derivative with 1, 3, 4-oxadiazole side chain and preparation and application thereof
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Paragraph 0055-0056; 0070; 0090; 0092; 0095; 0103, (2021/07/24)
The invention belongs to the field of medicinal chemistry, and particularly relates to a pleuromutilin derivative with a 1, 3, 4-oxadiazole side chain and preparation and application thereof The pleuromutilin derivative with the 1, 3, 4-oxadiazole side chain is a compound shown in a formula 2 or a pharmaceutically acceptable salt thereof, and a solvent compound, an enantiomer, a diastereoisomer and a tautomer of the compound shown in the formula 2 or the pharmaceutically acceptable salt thereof or a mixture of the solvent compound, the enantiomer, the diastereoisomer and the tautomer in any proportion, including a racemic mixture. The pleuromutilin derivative has good antibacterial activity, is especially suitable for being used as a novel antibacterial agent for systemic system infection of animals or human beings, and has good water solubility.