Kinetics and mechanism of the acid-catalyzed bromination of ring-substituted acetophenones in methanol. Thermodynamics of the ketone-acetal-enol ether system in methanol and water
Rearrangement of Hydroxylated Pinene Derivatives to Fenchone-Type Frameworks: Computational Evidence for Dynamically-Controlled Selectivity
作者:Marcus Blümel、Shota Nagasawa、Katherine Blackford、Stephanie R. Hare、Dean J. Tantillo、Richmond Sarpong
DOI:10.1021/jacs.8b05804
日期:2018.7.25
An acid-catalyzed Prins/semipinacolrearrangementcascade reaction of hydroxylated pinene derivatives that leads to tricyclic fenchone-type scaffolds in very high yields and diastereoselectivity has been developed. Quantum chemical analysis of the selectivity-determining step provides support for the existence of an extremely flat potential energy surface around the transition state structure. This
A novel PVP-I catalyzed acetalizations/transacetalizations of carbonyl compounds has been developed processing with a mild and easy handling fashion. Different types of Acyclic and cyclic acetals were prepared from carbonyl compounds or their acetals successfully. Further applications of newly developed catalytic combination were testified. This protocol featured with simplicity of operation, mild
A simple and efficient procedure for the synthesis of ethyl 2-methylthio- and ethyl 2-benzylthio-6-methyl(aryl)-pyrimidine-4-carboxylates and their corresponding acid derivatives is reported. The products are obtained in good yields via the cyclocondensation reaction of ethyl 4-alkoxy-2-oxo-4-methyl(aryl)-but-3-enoates with 2-methylisothiourea sulfate or 2-benzylisothiourea hydrochloride, under mild
Shell Cross‐Linked Micelles as Nanoreactors for Enantioselective Three‐Step Tandem Catalysis
作者:Michael Kuepfert、Aaron E. Cohen、Olivia Cullen、Marcus Weck
DOI:10.1002/chem.201804956
日期:2018.12.12
enantio‐enriched alcohols in the cross‐linked shell, and nucleophilic base‐catalyzed acylation in the hydrophobic core. The catalysts are positioned in close proximity on a single micelle support to take advantage of the intramicellar substrate diffusion, yet they are sufficiently spaced apart from each other in physically distinct microenvironments. These compartmentalized micelles are substrate selective
Antimalarial activity of 4-(5-trifluoromethyl-1H-pyrazol-1-yl)-chloroquine analogues
作者:Wilson Cunico、Cleber A. Cechinel、Helio G. Bonacorso、Marcos A.P. Martins、Nilo Zanatta、Marcus V.N. de Souza、Isabela O. Freitas、Rodrigo P.P. Soares、Antoniana U. Krettli
DOI:10.1016/j.bmcl.2005.10.033
日期:2006.2
the eight (4,5-dihydropyrazol-1-yl) chloroquine 2derivatives tested showed a significant activity in vitro, thus, are a promising new class of antimalarials. The three most active ones were also tested in vivo against Plasmodium berghei in mice. However, the (pyrazol-1-yl) chloroquine 3 derivatives were mostly inactive, suggesting that the aromatic functionality of the pyrazole ring was critical.