Discovery of trypanocidal thiosemicarbazone inhibitors of rhodesain and TbcatB
摘要:
Human African trypanosomiasis ( HAT) is caused by the protozoan parasite Trypanosoma brucei. The cysteine proteases of T. brucei have been shown to be crucial for parasite replication and represent an attractive point for therapeutic intervention. Herein we describe the synthesis of a series of thiosemicarbazones and their activity against the trypanosomal cathepsins TbcatB and rhodesain, as well as human cathepsins L and B. The activity of these compounds was determined against cultured T. brucei, and specificity was assessed with a panel of four mammalian cell lines. (c) 2008 Elsevier Ltd. All rights reserved.
A transition metal-free cascade reaction using heterogeneous tin(IV)oxide catalyzed and iodine promoted synthesis of 3-aroylimidazo[1,2-a]pyridines
作者:Nirajkumar H. Jadhav、Sachin S. Sakate、Dnyaneshwar R. Shinde、Manohar G. Chaskar、Ramdas A. Pawar
DOI:10.1016/j.tetlet.2020.152250
日期:2020.8
synthesis of 3-aroylimidazo[1,2-a]pyridines. The methodology was further extended for the one-pot three-component synthesis of 3-aroylimidazo[1,2-a]pyridines using acetophenone, benzaldehyde, and 2-aminopyridine derivatives. The present protocol describes the easy purification methodology in the synthesis of 3-aroylimidazo[1,2-a]pyridines.
在环境空气气氛下,通过SnO 2 / I 2催化体系在甲苯中使用查尔酮和2-氨基吡啶实现了3-芳基咪唑并[ 1,2 - a ]吡啶的级联合成。在3-芳基咪唑并[1,2]合成过程中,该催化剂对具有2-氨基吡啶,4-甲基2-氨基吡啶和5-甲基2-氨基吡啶的各种芳族和杂环查耳酮的广泛底物范围显示出高活性。-一个]吡啶。该方法进一步扩展为使用苯乙酮,苯甲醛和2-氨基吡啶衍生物一锅法合成3-芳基咪唑并[ 1,2 - a ]吡啶。本协议描述了3-芳基咪唑并[ 1,2 - a ]吡啶的合成中的简便纯化方法。
Base-Catalyzed Three-Component Reaction between Chalcones, Isothiocyanates, and Sulfur: Access to Thiazole-2-thiones
作者:Thanh Binh Nguyen、Pascal Retailleau
DOI:10.1021/acs.orglett.1c01653
日期:2021.7.16
A convenient synthesis of thiazole-2-thiones was developed based on base-catalyzed three-component reactions between chalcones, isothiocyanates, and elemental sulfur.
基于查耳酮、异硫氰酸酯和元素硫之间的碱催化三组分反应,开发了一种方便的噻唑-2-硫酮合成方法。
Enantioselective Seleno‐Michael Addition Reactions Catalyzed by a Chiral Bifunctional N‐Heterocyclic Carbene with Noncovalent Activation
作者:En Li、Jiean Chen、Yong Huang
DOI:10.1002/anie.202202040
日期:2022.6.7
A highly enantioselective Michael addition reaction of alkyl selenols to enones is reported. The development of a chiral bifunctional N-heterocycliccarbene (NHC)/thiourea catalyst was key in obtaining the chiral β-seleno ketones with remarkable selectivity.
Cyclic cysteine analogues were efficiently used as constrained unnatural amino acids proving able to induce stable conformation in Leu-Val containing peptides. These ultra-short peptides were then used as chiral ligands in copper(II) complexes and applied to the asymmetricMichaeladdition on differently substituted chalcones.
环状半胱氨酸类似物被有效地用作受限非天然氨基酸,证明能够在含有 Leu-Val 的肽中诱导稳定构象。然后将这些超短肽用作铜 (II) 配合物中的手性配体,并应用于不同取代的查耳酮的不对称迈克尔加成。
Lactone Enolates of Isochroman-3-ones and 2-Coumaranones: Quantification of Their Nucleophilicity in DMSO and Conjugate Additions to Chalcones
作者:Mohammad Sadeq Mousavi、Antonia Di Mola、Giovanni Pierri、Consiglia Tedesco、Magenta J. Hensinger、Aijia Sun、Yilan Wang、Peter Mayer、Armin R. Ofial、Antonio Massa
DOI:10.1021/acs.joc.4c00277
日期:——
Owing to stereoelectronic effects, lactones often deviate in reactivity from their open-chain ester analogues as demonstrated by the CH acidity (in DMSO) of 3-isochromanone (pKa = 18.8) and 2-coumaranone (pKa = 13.5), which is higher than that of ethyl phenylacetate (pKa = 22.6). We have now characterized the reactivity of the lactone enolates derived from 3-isochromanone and 2-coumaranone by following
由于立体电子效应,内酯的反应性通常与其开链酯类似物不同,如 3-异色满酮 (p Ka = 18.8) 和 2-香豆酮 (p Ka = 13.5 )的 CH 酸度(在 DMSO 中)所证明的那样,高于苯乙酸乙酯 (p K a = 22.6)。现在,我们通过跟踪 3-异苯并二氢吡喃酮和 2-香豆酮衍生的内酯烯醇化物与对醌甲基化物和亚芳基丙二酸酯(参考亲电子试剂)在 20 °C 下在 DMSO 中的迈克尔反应动力学,表征了它们的反应性。通过 Mayr-Patz 方程 lg k 2 = s N ( N + E ) 对实验确定的二阶速率常数k 2进行评估,提供了内酯烯醇化物的亲核性参数N (和s N )。通过将它们在迈尔亲核性尺度上的位置定位,它们的亲电反应伙伴的范围变得可预测,并且我们展示了一种新的催化方法,用于在甲苯中的相转移条件下内酯烯醇化物与查尔酮的一系列碳-碳键形成反应。