Synthesis and fungicidal activity of 3,5-dichloropyrazin-2(1H)-one derivatives
摘要:
We synthesized a family of 3,5-dichloropyrazin-2(1H)-one derivatives and assessed their in vitro fungicidal activity against Candida albicans. Compounds 11 and 20 were most active against C. albicans and induced accumulation of reactive oxygen species in this pathogen. Using a genome-wide approach in the yeast Saccharomyces cerevisiae, we demonstrated that genes involved in vacuolar functionality and DNA-related functions play an important role in cellular mechanisms underlying the fungicidal activity of these compounds. (C) 2009 Elsevier Ltd. All rights reserved.
Alkylation of 3,5-dichloro-2(1H)-pyrazinones using malonate esters
作者:Nigam M. Mishra、Vsevolod A. Peshkov、Olga P. Pereshivko、Sachin G. Modha、Erik V. Van der Eycken
DOI:10.1016/j.tetlet.2012.06.080
日期:2012.8
3-alkylation of 3,5-dichloro-2(1H)-pyrazinones with various malonate esters is described. The method constitutes a simple example of a C–C bond forming process at the 3-position of the pyrazinone core allowing to attain 3-substituted pyrazinones in good to high yields. 3-Alkylation of 3,5-dichloro-2(1H)-pyrazinones with acetoacetic ester was accompanied by further retro-Claisen fragmentation.
Diversely Substituted Imidazo[1,2-<i>a</i>]pyrazine-8-oxo-3-carbaldehydes: An Iodine-Mediated Cyclization/Oxidation Approach
作者:Nigam M. Mishra、Dipak D. Vachhani、Sachin G. Modha、Erik V. Van der Eycken
DOI:10.1002/ejoc.201201150
日期:2013.2
and efficient iodine-mediated intramolecular heteroannulation approach for the construction of the imidazo[1,2-a]pyrazinone core has been developed. Under ambient conditions, this metal-free protocol allows easy access to densely functionalized imidazo[1,2-a]pyrazinone-3-carbaldehydes or (aminomethyl)imidazo[1,2-a]pyrazinones from substrates containing terminal alkynes by cyclization and subsequent
The title compounds were obtained from reaction of variously substituted 2(1H)pyrazinones with acetylenic derivatives. Experimental evidence points out to a two step mechanism : a DielsAlder cycloaddition followed by immediate decomposition of the adducts into the title products via two competitive retro DielsAlderreactions. The product distribution, which is shown to be highly dependent on the
Microwave-Assisted Synthesis of Pyrazino[2,1-b]quinazolines and 3-Indolyl-2(1H)-pyrazinones Employing a Chemoselective Silver(I)- and Gold(I)-Catalyzed Reaction
作者:Dipak D. Vachhani、Vaibhav P. Mehta、Sachin G. Modha、Kristof Van Hecke、Luc VanMeervelt、Erik V. Van der Eycken
DOI:10.1002/adsc.201100881
日期:2012.5.21
Novel microwave‐assisted syntheses of pyrazino[2,1‐b]quinazolines and 3‐indolyl‐2(1H)‐pyrazinones employingsilver(I)‐ or gold(I)‐catalyzed protocols have been elaborated. The scope and limitations of these processes have been investigated.