Results 21 to 30 of about 29,422 (294)

Highly efficient and enzymatic regioselective undecylenoylation of gastrodin in 2-methyltetrahydrofuran-containing systems. [PDF]

PLoS ONE, 2014
Highly efficient and regioselective acylation of pharmacologically interesting gastrodin with vinyl undecylenic acid has been firstly performed through an enzymatic approach. The highest catalytic activity and regioselectivity towards the acylation of 7'-
Rongling Yang, Xueming Liu, Zhiyi Chen, Chunying Yang, Yaosheng Lin, Siyuan Wang   +5 more
doaj   +1 more source

Regioselective conversion of epoxides to β-acetoxy alcohols catalyzed by a novel green and recyclable phase transfer catalyst [PDF]

شیمی کاربردی روز, 2018
A new mild and efficient procedure for the ring opening of epoxides by acetate anion in the presence of catalytic amounts of silica-bound polyethylene glycol substituted 1-methylimidazolium bromide, SiO2-PEG-ImBr, as an effective heterogeneous phase ...
ندا عیاشی, Mehdi Fallah-Mehrjardi, علیرضا کیاست   +2 more
doaj   +1 more source

Reactivity, Regioselectivity, and Synthetic Application of 2-Pyrenyl Units in Scholl Reactions

, 2023
We herein report the reactivity and regioselectivity of 2-pyrenyl as a coupling unit in Scholl reactions. On the basis of the Scholl reactions of hexaarylbenzene substrates, we have found that pyrenyl units are preferably oxidized over naphthyl and ...
Han, Chen, Ethan Chi Ho, Wen, Zeming, Xia, Felix R., Fischer, Qian, Miao, Sai Ho, Pun   +5 more
core   +1 more source

The Highly Regioselective Synthesis of Novel Imidazolidin-2-Ones via the Intramolecular Cyclization/Electrophilic Substitution of Urea Derivatives and the Evaluation of Their Anticancer Activity

Molecules, 2021
A series of novel 4-(het)arylimidazoldin-2-ones were obtained by the acid-catalyzed reaction of (2,2-diethoxyethyl)ureas with aromatic and heterocyclic C-nucleophiles.
Almir S. Gazizov, Andrey V. Smolobochkin, Elizaveta A. Kuznetsova, Dinara S. Abdullaeva, Alexander R. Burilov, Michail A. Pudovik, Alexandra D. Voloshina, Victor V. Syakaev, Anna P. Lyubina, Syumbelya K. Amerhanova, Julia K. Voronina   +10 more
doaj   +1 more source

Insights into the Mechanism and Regioselectivity of Palladium-Catalyzed Arylation of α,β-Unsaturated Ketones

, 2023
Transition-metal catalyzed coupling reactions of carbonyl compounds using simple chemical feedstocks have become a cornerstone of modern synthetic organic chemistry.
Xiaoxi, Su, Jinbo, Luo, Zhizheng, Chen, Shuanglin, Qu   +3 more
core   +1 more source

An efficient synthesis of novel triazoles incorporating barbituric motifs via [3+2] cycloaddition reaction: An experimental and theoretical study [PDF]

Journal of the Serbian Chemical Society, 2018
In this work, the synthesis of novel triazole derivatives with barbituric motifs in good yields is described. The alkyne was prepared through the Knoevenagel reaction of barbituric derivatives with ortho and para O-propargylated hydroxybenzaldehyde.
Darroudi Mahdieh, Sarrafi Yaghoub, Hamzehloueian Mahshid   +2 more
doaj   +1 more source

Heavy atom effects in the Paternò–Büchi reaction of pyrimidine derivatives with 4,4’-disubstituted benzophenones

Beilstein Journal of Organic Chemistry, 2011
The regioselectivity and the photochemical efficiency were investigated in the Paternò–Büchi reaction of 1,3-dimethylthymine (DMT) and 1,3-dimethyluracil (DMU) with benzophenone (1b) and some 4,4’-disubstituted derivatives (dimethoxy (1a), difluoro (1c),
Feng-Feng Kong, Jian-Bo Wang, Qin-Hua Song   +2 more
doaj   +1 more source

The Nitrilimine–Alkene Cycloaddition Regioselectivity Rationalized by Density Functional Theory Reactivity Indices

Molecules, 2017
Conventional frontier molecular orbital theory is not able to satisfactorily explain the regioselectivity outcome of the nitrilimine–alkene cycloaddition.
Giorgio Molteni, Alessandro Ponti
doaj   +1 more source

On the regioselective molecular sieves-promoted oxidative three-component synthesis of fused-benzimidazoles from $\beta $-ketoesters

Comptes Rendus. Chimie, 2022
The regioselectivity of molecular sieves-promoted oxidative three-component reaction between $\beta $-ketoesters, aromatic o-diamines and acrolein, leading to pyrido[1,2-a]benzimidazoles, has been investigated by a combination of experimental and ...
Martin, Anthony, Cheshmedzhieva, Diana, Palermo, Valeria, Liéby-Muller, Frédéric, Romanelli, Gustavo P., Gaudel-Siri, Anouk, Coquerel, Yoann, Constantieux, Thierry, Rodriguez, Jean   +8 more
doaj   +1 more source

Reverse Regioselectivity in Reductive Ring Opening of Epoxide Enabled by Zirconocene and Photoredox Catalysis

, 2021
A ring opening of epoxide with zirconocene and photoredox catalysis has been developed. Compared to the ring opening methods with titanocene, the present protocol exhibited reverse regioselectivity to afford more-substituted alcohols via putative less ...
Eisuke, Ota, Marina, Hirao, Junichiro, Yamaguchi, Aiko, Funabashi, Natsuhiko, Sugimura, Kazuhiro, Aida   +5 more
core   +1 more source