mali. Compounds C1 and C2 showed the higher activity with average EC50 values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure-activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkylgroup in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between
[EN] MYOGLOBIN-BASED CATALYSTS FOR CARBENE TRANSFER REACTIONS<br/>[FR] CATALYSEURS À BASE DE MYOGLOBINE POUR RÉACTIONS DE TRANSFERT DE CARBÈNE
申请人:UNIV ROCHESTER
公开号:WO2016086015A1
公开(公告)日:2016-06-02
Methods are provided for carrying out carbene transfer transformations such as olefin cyclopropanation reactions, carbene heteroatom-H insertion reactions (heteroatom = N, S, Si), sigmatropic rearrangement reactions, and aldehyde olefination reactions with high efficiency and selectivity by using a novel class of myoglobin-based biocatalysts. These methods are useful for the synthesis of a variety of organic compounds which contain one or more new carbon-carbon or carbon-heteroatom (N, S, or Si) bond. The methods can be applied for conducting these transformations in vitro (i.e., using the biocatalyst in isolated form) and in vivo (i.e., using the biocatalyst in a whole cell system).
Borane-Catalyzed Reductive α-Silylation of Conjugated Esters and Amides Leaving Carbonyl Groups Intact
作者:Youngchan Kim、Sukbok Chang
DOI:10.1002/anie.201508669
日期:2016.1.4
valuable α‐silyl carbonyl products. The α‐silylation occurs chemoselectively, thus leaving the labile carbonylgroups intact. The reaction features a broad scope of both acyclic and cyclic substrates, and the synthetic utility of the obtained α‐silyl carbonyl products is also demonstrated. Mechanistic studies revealed two operative steps: fast 1,4‐hydrosilylation of conjugated carbonyls and then slow
本文描述了由B(C 6 F 5)3催化的α,β-不饱和酯和酰胺的氢化硅烷化反应,以提供具有合成价值的α-甲硅烷基羰基产物。α-甲硅烷基化是化学选择性发生的,因此保留了不稳定的羰基。该反应具有无环和环状底物的广泛范围,并且还证明了所得α-甲硅烷基羰基产物的合成效用。机理研究揭示了两个操作步骤:共轭羰基的快速1,4-氢化硅烷化,然后减慢甲硅烷基醚中间体的甲硅烷基迁移。
Benzyne-Mediated Esterification Reaction
作者:Jinlong Zhao、Jiarong Shi、Yang Li
DOI:10.1021/acs.orglett.1c02702
日期:2021.9.17
A benzyne-mediated esterification of carboxylic acids and alcohols under mild conditions has been realized, which is made possible via a selective nucleophilic addition of carboxylic acid to benzyne in the presence of alcohol. After a subsequent transesterification with alcohol, the corresponding esters can be produced efficiently. This benzyne-mediated protocol can be used on the modification of Ibuprofen
Herein we show that glycerol can be considered as a promising cheap and green solvent for the regioselective β,β-diarylation of alkenes. Whereas this reaction is generally catalyzed under an inert atmosphere by expensive phosphine or carbene-palladium complexes, we show here that the diarylation of alkenes can be conveniently achieved in glycerol in the presence of air-stable palladium nanoparticles. These palladium nanoparticles were stabilized over a sugar-based surfactant derived from biomass. By an adjustment of the reaction temperature, we were able to control the mono- and diarylation step of alkenes, thus offering a convenient route to unsymmetrical diarylated alkenes. At the end of the reaction, the diarylated alkenes were cleanly and selectively extracted from the glycerol-palladium catalytic phase using supercritical carbon dioxide, thus affording a convenient purification work-up. Within the framework of green chemistry, this work combines (i) catalysis in a cheap, safe and sustainable medium, (ii) easily made and air-stable palladium nanoparticles as the catalyst, and (iii) a clean and selective extraction of the reaction products with supercritical carbon dioxide.