Development of a Formal Catalytic Asymmetric [4 + 2] Addition of Ethyl-2,3-butadienoate with Acyclic Enones
摘要:
Allene esters are unique not only as excellent electrophiles but also because of their ability for subsequent reactivity after the initial nucleophilic attack. A mechanistically inspired cyclization using ethyl-2,3-butadienoate and acyclic enones to provide dihydropyrans In excellent yields and enantioselectivity under solvent-free conditions at room temperature is reported.
Development of a Formal Catalytic Asymmetric [4 + 2] Addition of Ethyl-2,3-butadienoate with Acyclic Enones
摘要:
Allene esters are unique not only as excellent electrophiles but also because of their ability for subsequent reactivity after the initial nucleophilic attack. A mechanistically inspired cyclization using ethyl-2,3-butadienoate and acyclic enones to provide dihydropyrans In excellent yields and enantioselectivity under solvent-free conditions at room temperature is reported.
Synthetic chalcones as efficient inhibitors of Mycobacterium tuberculosis protein tyrosine phosphatase PtpA
作者:Louise Domeneghini Chiaradia、Alessandra Mascarello、Marcela Purificação、Javier Vernal、Marlon Norberto Sechini Cordeiro、María Emilia Zenteno、Andréa Villarino、Ricardo José Nunes、Rosendo Augusto Yunes、Hernán Terenzi
DOI:10.1016/j.bmcl.2008.09.105
日期:2008.12
In the search for lead compounds for new drugs for tuberculosis, the activity of 38 synthetic chalcones were assayed for their potential inhibitory action towards a protein tyrosine phosphatase from Mycobacterium tuberculosis - PtpA. The compounds were obtained by aldolic condensation between aldehydes and acetophenones, under basic conditions. Five compounds presented moderate or good activity. The structure - activity analysis reveals that the predominant factor for the activity is the molecule planarity/hydrophobicity and the nature of the substituents. (C) 2008 Elsevier Ltd. All rights reserved.
Antihyperglycemic activity of naphthylchalcones
作者:Rosangela Guollo Damazio、Ana Paula Zanatta、Luisa Helena Cazarolli、Louise Domeneghini Chiaradia、Alessandra Mascarello、Ricardo José Nunes、Rosendo Augusto Yunes、Fátima Regina Mena Barreto Silva
DOI:10.1016/j.ejmech.2009.12.017
日期:2010.4
The purpose of the present work was to investigate, following previous works, naphthylchalcones as antihyperglycemic agent in glucose loaded animal model, insulin secretion as well as the action of these compounds on glucose uptake in a target tissue of insulin. The naphthylchalcones were found to have an acute serum glucose-lowering effect in hyperglycemic normal rats. In addition, chalcones 2 and 4 stimulated significantly the insulin secretion induced by glucose. These results suggest that the presence of nitro group and their position in the phenyl rings are responsible for the antihyperglycemic activity of chalcones. Additionally, the effect of chalcones on serum glucose-lowering seems to be a consequence of insulin secretion and these chalcones represent potential compounds with strong antihyperglycemic properties. (C) 2009 Elsevier Masson SAS. All rights reserved.
Development of a Formal Catalytic Asymmetric [4 + 2] Addition of Ethyl-2,3-butadienoate with Acyclic Enones
作者:Kumar Dilip Ashtekar、Richard J. Staples、Babak Borhan
DOI:10.1021/ol202301f
日期:2011.11.4
Allene esters are unique not only as excellent electrophiles but also because of their ability for subsequent reactivity after the initial nucleophilic attack. A mechanistically inspired cyclization using ethyl-2,3-butadienoate and acyclic enones to provide dihydropyrans In excellent yields and enantioselectivity under solvent-free conditions at room temperature is reported.