nickel/Lewis acid (LA) cooperative catalysis to give beta-cyano-substituted acrylates and acrylamides, respectively, in highly stereoselective and regioselective manners. The resulting adducts serve as versatile synthetic building blocks through chemoselective transformations of the ester, amide, and cyano groups as demonstrated by the synthesis of typical structures of beta-cyano ester, beta-amino
Et2Zn-mediated stoichiometric C(sp)-H silylation of 1-alkynes and chlorosilanes
作者:Pan Huang、Dawen Xu、Robert M. Reich、Felix Kaiser、Boping Liu、Fritz E. Kühn
DOI:10.1016/j.tetlet.2019.05.017
日期:2019.6
series of functional groups are tolerated in this reaction. Mechanistic studies support Zn alkynilides as intermediates in the reaction. This reaction protocol provides a practical method for the preparation of alkynylsilanes and expands the application of organometallic zinc in organicsynthesis.
Amino derivatives of indolone-N-oxide: Preparation and antiplasmodial properties
作者:Ennaji Najahi、Nambinina V. Rakotoarivelo、Alexis Valentin、Françoise Nepveu
DOI:10.1016/j.ejmech.2014.02.038
日期:2014.4
There is an urgent need for new antimalarial drugs with novel mechanisms of action on novel targets. Indolone-N-oxides (INODs) display antimalarial properties in vitro and in vivo, but identified leads such as 6-(4-chloro-phenyl)-5-oxy-[1,3]dioxolo[4,5-f]indol-7-one 1, suffer from very poor aqueous solubility. In this study, structural modifications have been made by introducing various amino and bulky groups to produce sufficiently water soluble and active compounds for further pharmacological and pharmacokinetic studies. We report here the preparation of twelve novel amino derivatives and their anti-plasmodial activities including those of two other structurally known compounds. The 5-methoxy-2-(4-morpholin-4-yl-phenyl)-1-oxy-indol-3-one, 9, has the highest antiplasmodial activity in vitro (IC50 = 6.5 nM; FcB1 strain) and selectivity index (SI (CC(50)MCF7/IC50 FcB1) = 4538.5). The 6-amino-2-(4-chloro-phenyl)-1-oxy-indol-3-one, 14, (IC50 = 183 nM; SI = 60), is an excellent candidate for further mechanistic studies. Indeed, this is structurally the closest analogue to the current lead, 1, bearing an NH2 group at R-2 offering possibilities for functionalization and labeling. (C) 2014 Elsevier Masson SAS. All rights reserved.
Zinc-Catalyzed Silylation of Terminal Alkynes
作者:Ronald J. Rahaim、Jared T. Shaw
DOI:10.1021/jo702557d
日期:2008.4.1
A rapid and high-yielding silylation of terminal alkynes employing TMSOTf and catalytic quantities of Zn(OTf)(2) has been developed. The reaction works well for a variety of substrates including reactive esters. Fifteen examples with yields of > 90% are reported.