Efficient synthesis of 4-substituted pyrazole via microwave-promoted Suzuki cross-coupling reaction
摘要:
Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds. In contrast to 3 or 5-aryl pyrazole, the preparation of 4-aryl pyrazole is fairly rare. Utilizing microwave irradiation, the synthesis of 4-substituted-arylpyrazole via Suzuki cross-coupling has been developed with a wide range of substrates. The remarkable advantages of this method are mild reaction conditions, simple operation, high yield, and short reaction time. Product structures were identified by MS, H-1 NMR, C-13 NMR, and elemental analysis. (C) 2014 Qiong-You Wu and Guang-Fu Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
Inhibitors of Acyl-CoA:Cholesterol <i>O</i>-Acyltransferase. 2. Identification and Structure−Activity Relationships of a Novel Series of <i>N</i>-Alkyl-<i>N</i>-(heteroaryl-substituted benzyl)-<i>N‘</i>-arylureas
tuted benzyl)-N'-arylurea and related derivatives represented by 2 and 3 have been prepared and evaluated for their ability to inhibitacyl-CoA:cholesterol O-acyltransferase in vitro and to lower plasma cholesterol levels in cholesterol-fed rats in vivo. Among these novel compounds, the type 3 series was superior. A pyrazol-3-yl group on the N-benzyl group of this trisubstituted urea (i.e. 3, Ar1 =
Probing the Azaaurone Scaffold against the Hepatic and Erythrocytic Stages of Malaria Parasites
作者:Marta P. Carrasco、Marta Machado、Lídia Gonçalves、Moni Sharma、Jiri Gut、Amanda K. Lukens、Dyann F. Wirth、Vânia André、Maria Teresa Duarte、Rita C. Guedes、Daniel J. V. A. dos Santos、Philip J. Rosenthal、Ralph Mazitschek、Miguel Prudêncio、Rui Moreira
DOI:10.1002/cmdc.201600327
日期:2016.10.6
potential of azaaurones as dual‐stage antimalarial agents was investigated by assessing the effect of a small library of azaaurones on the inhibition of liver and intraerythrocytic lifecycle stages of the malariaparasite. The whole series was screened against the blood stage of a chloroquine‐resistant Plasmodium falciparum strain and the liver stage of P. berghei, yielding compounds with dual‐stage activity
Azaaurones as Potent Antimycobacterial Agents Active against MDR‐ and XDR‐TB
作者:André Campaniço、Marta P. Carrasco、Mathew Njoroge、Ronnett Seldon、Kelly Chibale、João Perdigão、Isabel Portugal、Digby F. Warner、Rui Moreira、Francisca Lopes
DOI:10.1002/cmdc.201900289
日期:2019.8.20
isosteric counterparts, azaaurones and N-acetylazaaurones, against Mycobacterium tuberculosis. Aurones were found to be inactive at 20 μm, whereas azaaurones and N-acetylazaaurones emerged as the most potent compounds, with nine derivatives displaying MIC99 values ranging from 0.4 to 2.0 μm. In addition, several N-acetylazaaurones were found to be activeagainst multidrug-resistant (MDR) and extensively drug-resistant
Palladium-catalysed direct diarylations of pyrazoles with aryl bromides: a one step access to 4,5-diarylpyrazoles
作者:Abdelilah Takfaoui、Liqin Zhao、Rachid Touzani、Pierre H. Dixneuf、Henri Doucet
DOI:10.1016/j.tetlet.2014.01.079
日期:2014.3
The palladium-catalyseddirect arylation of pyrazoles with aryl halides, using PdCl(C3H5)(dppb)/KOAc catalyst, reveals a similar reactivity of C4 and C5 CH bonds of pyrazoles, whereas the C3 CH bond is almost unreactive, and gives access in one step to a variety of 4,5-diarylpyrazoles. This CH bond functionalisation reaction tolerates a variety of substituents on the aryl bromide such as nitro, cyano
使用PdCl(C 3 H 5)(dppb)/ KOAc催化剂,钯催化吡唑与芳基卤化物的直接芳基化反应显示出吡唑的C4和C5 C H键具有相似的反应性,而C3 C H键几乎不具有反应性,并一步一步即可获得各种4,5-二芳基吡唑类化合物。该C H键官能化反应容许芳基溴化物上的各种取代基,例如硝基,氰基,甲酰基,丙酰基,酯,氯,氟或三氟甲基。
Pd-Catalysed Direct 5-Arylation of 1-Methylpyrazole with Aryl Bromides
作者:Hamed Ammar、Henri Doucet、Anissa Beladhria、Kassem Beydoun、Ridha Salem
DOI:10.1055/s-0030-1260076
日期:2011.8
the base and DMAc as the solvent, promotes the 5-arylation in moderate to high selectivities and yields. A wide variety of aryl and heteroaryl bromide derivatives have been successfully employed. Their electronic and steric properties also have an influence on the regioselectivities and yields of the coupling products. Both electron-poor and electron-rich aryl bromides gave satisfactory results, although