(E)‐stilbenes were synthesized by Mizoroki–Heck reactions and tested for their ability to inhibit the enzymes acetyl‐ and butyrylcholinesterase. Several of them are good inhibitors of butyrylcholinesterase; one of them carrying an extra fluorine substituent is a 94‐fold stronger inhibitor of butyrylcholinesterase than of acetylcholinesterase.
申请人:Board of Trustees of Michigan State University
公开号:US20040030197A1
公开(公告)日:2004-02-12
A process to synthesize substituted phenols such as those of the general formula RR′R″Ar(OH) wherein R, R′, and R″ are each independently hydrogen or any group which does not interfere in the process for synthesizing the substituted phenol including, but not limited to, halo, alkyl, alkoxy, carboxylic ester, amine, amide; and Ar is any variety of aryl or hetroaryl by means of oxidation of substituted arylboronic esters is described. In particular, a metal-catalyzed C—H activation/borylation reaction is described, which when followed by direct oxidation in a single or separate reaction vessel affords phenols without the need for any intermediate manipulations. More particularly, a process wherein Ir-catalyzed borylation of arenes using pinacolborane (HBPin) followed by oxidation of the intermediate arylboronic ester by OXONE is described.
Synthesis and antimicrobial activity of (E) stilbene derivatives
作者:Sabrina Albert、Ralf Horbach、Holger B. Deising、Bianka Siewert、René Csuk
DOI:10.1016/j.bmc.2011.07.015
日期:2011.9
Plants use multiple defence mechanisms comprising both constitutive and inducible barriers to prevent entering of phytopathogenic micro-organisms. In many plant species one of the most efficient responses to combat attacking microbes is the rapid synthesis of antimicrobial low molecular weight phytoalexins, for example, resveratrol, 3,5,4'-trihydroxystilbene (1). Resveratrol and its natural derivatives, however, display only moderate antimicrobial effects. Nevertheless, resveratrol may be a useful lead structure for the chemical synthesis of antimicrobials. In this study, several series of stilbenes have been synthesized, starting from the aldehydes using Wittig reactions to access the corresponding styrenes that were subjected to Mizoroki-Heck reactions to yield the stilbenes in good yields. The stilbenes were tested in an agar diffusion assay against several bacteria and fungi. For some of these compounds the inhibiting zones for bacteria and fungi were comparable with those of the antibiotics tetracycline, streptomycin, ampicillin, or kanamycin, directed against prokaryotes, and nourseothricin or hygromycin controlling fungi, respectively. (C) 2011 Elsevier Ltd. All rights reserved.
C−H Activation/Borylation/Oxidation: A One-Pot Unified Route To Meta-Substituted Phenols Bearing Ortho-/Para-Directing Groups
作者:Robert E. Maleczka,、Feng Shi、Daniel Holmes、Milton R. Smith
DOI:10.1021/ja0349857
日期:2003.7.1
An efficient one-pot C-H activation/borylation/oxidation protocol for the preparation of phenols is described. This method is particularly attractive for the generation of meta-substituted phenols bearing ortho-/para-directing groups, as such substrates are difficult to access by other phenol syntheses.