Ligand-free Suzuki–Miyaura cross-coupling with low Pd content: rapid development by a fluorescence-based high-throughput screening method
作者:Taeho Lim、Jeong Yup Ryoo、Mingyeong Jang、Min Su Han
DOI:10.1039/d0ob02359k
日期:——
high-content-Pd catalysts. Thus, in this study, a highly efficient SM cross-coupling was developed using metal oxidecatalysts: 0.02 mol% Pd, aqueous solvent, no ligand, and room temperature. Metal oxides containing low Pd content (ppm scale) were prepared by a simple co-precipitation method and used as a catalyst for the SM reaction. A fluorescence-based high-throughput screening (HTS) method was
Suzuki-Miyaura(SM)交叉偶联是形成碳-碳键的最有效策略之一,但是以前的方法存在一些缺点,例如需要复杂的配体,有毒的有机溶剂和高含量的Pd催化剂。因此,在这项研究中,使用金属氧化物催化剂(0.02摩尔%Pd,水性溶剂,无配体和室温)开发了高效的SM交叉偶联。通过简单的共沉淀方法制备了低Pd含量(ppm级)的金属氧化物,并将其用作SM反应的催化剂。为了快速评估催化活性和反应条件,开发了一种基于荧光的高通量筛选(HTS)方法。在各种金属氧化物中,Pd / Fe 2 O 3对SM反应显示出最高的活性。通过HTS进一步优化后,在最佳条件下获得了各种联芳基化合物:在温和的温度下在乙醇水溶液中的Pd / Fe 2 O 3(0.02 mol%Pd),没有任何配体。
Structurally Simple Inhibitors of Lanosterol 14α-Demethylase Are Efficacious In a Rodent Model of Acute Chagas Disease
作者:Praveen Kumar Suryadevara、Srinivas Olepu、Jeffrey W. Lockman、Junko Ohkanda、Mandana Karimi、Christophe L. M. J. Verlinde、James M. Kraus、Jan Schoepe、Wesley C. Van Voorhis、Andrew D. Hamilton、Frederick S. Buckner、Michael H. Gelb
DOI:10.1021/jm900030h
日期:2009.6.25
We report structure-activity studies of a large number of dialkyl imidazoles as inhibitors of Trypanosoma cruzi lanosterol-14 alpha-demethylase (L14DM). The compounds have a simple structure compared to posaconazole, another L14DM inhibitor that is an anti-Chagas drug candidate. Several compounds display potency for killing T cruzi amastigotes in vitro with values of EC50 in the 0.4-10 nM range. Two compounds were selected for efficacy studies in a mouse model of acute Chagas disease. At oral doses of 20-50 mg/kg given after establishment of parasite infection, the compounds reduced parasitemia in the blood to undetectable levels, and analysis of remaining parasites by PCR revealed a lack of parasites in the majority of animals. These dialkyl imidazoles are substantially less expensive to produce than posaconazole and are appropriate for further development toward an anti-Chagas disease clinical candidate.
Dialkylimidazole inhibitors of Trypanosoma cruzi sterol 14α-demethylase as anti-Chagas disease agents
作者:Praveen Kumar Suryadevara、Kishore Kumar Racherla、Srinivas Olepu、Neil R. Norcross、Hari Babu Tatipaka、Jennifer A. Arif、Joseph D. Planer、Galina I. Lepesheva、Christophe L.M.J. Verlinde、Frederick S. Buckner、Michael H. Gelb
DOI:10.1016/j.bmcl.2013.08.015
日期:2013.12
New dialkylimidazole based sterol 14 alpha-demethylase inhibitors were prepared and tested as potential anti-Trypanosoma cruzi agents. Previous studies had identified compound 2 as the most potent and selective inhibitor against parasite cultures. In addition, animal studies had demonstrated that compound 2 is highly efficacious in the acute model of the disease. However, compound 2 has a high molecular weight and high hydrophobicity, issues addressed here. Systematic modifications were carried out at four positions on the scaffold and several inhibitors were identified which are highly potent (EC50 <1 nM)against T. cruzi in culture. The halogenated derivatives 36j, 36k, and 36p, display excellent activity against T. cruzi amastigotes, with reduced molecular weight and lipophilicity, and exhibit suitable physicochemical properties for an oral drug candidate. (C) 2013 Elsevier Ltd. All rights reserved.
Design and Synthesis of Potent Nonpeptidic Farnesyltransferase Inhibitors Based on a Terphenyl Scaffold
作者:Junko Ohkanda、Jeffrey W. Lockman、Mohit A. Kothare、Yimin Qian、Michelle A. Blaskovich、Said M. Sebti、Andrew D. Hamilton
DOI:10.1021/jm0103099
日期:2002.1.1
By modification of key carboxylate, hydrophobic, and zinc-binding groups projected from a sterically restricted terphenyl scaffold, a series of simple and nonpeptide mimetics of the Cys-Val-Ile-Met tetrapeptide substrate of protein farnesyltransferase (FTase) have been designed and synthesized. A crystal structure of 4-nitro-2-phenyl-3'-methoxycarbonylbiphenyl shows that the triphenyl fragment provides a large hydrophobic surface that potentially mimics the hydrophobic side chains of the three terminal residues in the tetrapeptide. 2-Phenyl-3-(N-(1-(4-eyanobenzyl)-1H-imidazol-5-yl)methyl)amino-3'carboxylbiphenyl, in which the free thiol group was replaced with a 1-(4-cyanobenzyl)imidazole group, shows submicromolar inhibition activity against FTase in vitro and inhibits H-Ras processing in whole cells.
Development of a Tripeptide Mimetic Strategy for the Inhibition of Protein Farnesyltransferase
作者:Mohit A. Kotharé、Junko Ohkanda、Jeffrey W. Lockman、Yimin Qian、Michelle A. Blaskovich、Said M. Sebti、Andrew D. Hamilton
DOI:10.1016/s0040-4020(00)00890-5
日期:2000.12
This paper describes the development of a novel terphenyl-based tripeptide mimetic of the CAAX carboxy terminal sequence of Ras. We employ a concise synthesis to form a series of differently functionalized terphenyl inhibitors of protein farnesyltransferase (PFTase), exemplified by 5, 6 and 7. The key reaction in the synthesis of the terphenyl methyl ester 13, and therefore 6 and 7, was the Pd-catalyzed chemoselective Suzuki cross-coupling of 3-bromo-4-chloronitrobenzene 16 with an appropriate boronic acid derivative utilizing a commercially available, electron rich phosphine Ligand. We further show that one member of this series is a potent inhibitor of PFTase. (C) 2000 Elsevier Science Ltd. All rights reserved.