2251-65-2Relevant articles and documents
Inhibitors of ribosome rescue arrest growth of francisella tularensis at all stages of intracellular replication
Goralski, Tyler D. P.,Dewan, Kalyan K.,Alumasa, John N.,Avanzato, Victoria,Place, David E.,Markley, Rachel L.,Katkere, Bhuvana,Rabadi, Seham M.,Bakshi, Chandra Shekhar,Keiler, Kenneth C.,Kirimanjeswara, Girish S.
, p. 3276 - 3282 (2016)
Bacteria require at least one pathway to rescue ribosomes stalled at the ends of mRNAs. The primary pathway for ribosome rescue is trans-translation, which is conserved in >99% of sequenced bacterial genomes. Some species also have backup systems, such as ArfA or ArfB, which can rescue ribosomes in the absence of sufficient trans-translation activity. Small-molecule inhibitors of ribosome rescue have broad-spectrum antimicrobial activity against bacteria grown in liquid culture. These compounds were tested against the tier 1 select agent Francisella tularensis to determine if they can limit bacterial proliferation during infection of eukaryotic cells. The inhibitors KKL-10 and KKL-40 exhibited exceptional antimicrobial activity against both attenuated and fully virulent strains of F. tularensis in vitro and during ex vivo infection. Addition of KKL-10 or KKL-40 to macrophages or liver cells at any time after infection by F. tularensis prevented further bacterial proliferation. When macrophages were stimulated with the proinflammatory cytokine gamma interferon before being infected by F. tularensis, addition of KKL-10 or KKL-40 reduced intracellular bacteria by >99%, indicating that the combination of cytokine-induced stress and a nonfunctional ribosome rescue pathway is fatal to F. tularensis. Neither KKL-10 nor KKL-40 was cytotoxic to eukaryotic cells in culture. These results demonstrate that ribosome rescue is required for F. tularensis growth at all stages of its infection cycle and suggest that KKL-10 and KKL-40 are good lead compounds for antibiotic development.
Prazosin-Related Compounds. Effect of Transforming the Piperazinylquinazoline Moiety into an Aminomethyltetrahydroacridine System on the Affinity for α1-Adrenoreceptors
Rosini, Michela,Antonello, Alessandra,Cavalli, Andrea,Bolognesi, Maria L.,Minarini, Anna,Marucci, Gabriella,Poggesi, Elena,Leonardi, Amedeo,Melchiorre, Carlo
, p. 4895 - 4903 (2003)
In a search for structurally new α1-adrenoreceptor (α1-AR) antagonists, prazosin (1)-related compounds 2-11 were synthesized and their affinity profiles were assessed by functional experiments in isolated rat vas deferens (α1A), spleen (β 1B), and aorta (α1D) and by binding assays in CHO cells expressing human cloned α1-AR subtypes. Transformation of the piperazinylquinazoline moiety of 1 into an aminomethyltetrahydroacridine system afforded compound 2, endowed with reduced affinity, in particular for the α1A-AR subtype. Then, to investigate the optimal features of the tricyclic moiety, the aliphatic ring of 2 was modified by synthesizing the lower and higher homologues 3 and 4. An analysis of the pharmacological profile, together with a molecular modeling study, indicated the tetrahydroacridine moiety as the most promising skeleton for α 1-antagonism. Compounds 5-8, where the replacement of the furoyl group of 2 with a benzoyl moiety afforded the possibility to evaluate the effect of the substituent trifluoromethyl on receptor binding, resulted, except for 7, in a rather surprising selectivity toward α1B-AR, in particular vs the α1A subtype. Also the insertion of the 2,6-dimethoxyphenoxyethyl function of WB 4101 on the tetrahydroacridine skeleton of 2, and/or the replacement of the aromatic amino function with a hydroxy group, affording derivatives 9-11, resulted in α1B-AR selectivity also vs the α1D subtype. On the basis of these results, the tetrahydroacridine moiety emerged as a promising tool for the characterization of the α1-AR, owing to the receptor subtype selectivity achieved by an appropriate modification of the lateral substituents.
Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates
Chattopadhyay, Buddhadeb,Hassan, Mirja Md Mahamudul,Hoque, Md Emdadul
supporting information, p. 5022 - 5037 (2021/05/04)
Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.
Rhodium(III)-catalyzed chemodivergent annulations between phenyloxazoles and diazos via C–H activation
Zhang, Xueguo,Wang, Peigen,Zhu, Liangwei,Chen, Baohua
supporting information, p. 695 - 699 (2020/06/28)
Acid-controlled, chemodivergent and redox-neutral annulations for the synthesis of isocoumarins and isoquinolinones have been realized via Rh(III)-catalyzed C[sbnd]H activation. Diazo compounds act as a carbene precursor, and coupling occurs in one-pot process, where adipic acid and trimethylacetic acid promote chemodivergent cyclizations.
Ni-Catalyzed C(sp2)-H alkylation ofN-quinolylbenzamides using alkylsilyl peroxides as structurally diverse alkyl sources
Kano, Taichi,Maruoka, Keiji,Matsumoto, Akira,Sakurai, Shunya,Tsuzuki, Saori
supporting information, p. 7942 - 7945 (2021/08/17)
A Ni-catalyzed direct C-H alkylation ofN-quinolylbenzamides using alkylsilyl peroxides as alkyl-radical precursors is described. The reaction forms a new C(sp3)-C(sp2) bondviathe selective cleavage of both C(sp3)-C(sp3) and C(sp2)-H bonds. This transformation shows a high functional-group tolerance and, due to the structural diversity of alkylsilyl peroxides, a wide range of alkyl chains including functional groups and complex structures can be introduced at theortho-position of readily availableN-quinolylbenzamide derivatives. Mechanistic studies suggest that the reaction involves a radical mechanism.
Synthesis and structure-activity relationship studies of n-monosubstituted aroylthioureas as urease inhibitors
Dawalamu,Fang, Hai-Lian,Fu, Zi-Juan,Li, Fang,Li, Ke,Li, Wei-Yi,Liu, Li,Ni, Wei-Wei,Ouyang, Hui,Xiao, Zhu-Ping,Ye, Ya-Xi,Zhu, Hai-Liang,Zhu, Wen-Yan,Zou, Xia
, p. 1046 - 1059 (2021/11/30)
Background: Thiourea is a classical urease inhibitor which is usually used as a positive control, and many N,N'-disubstituted thioureas have been determined as urease inhibitors. However, due to steric hindrance, N,N'-disubstituted thiourea motif could not bind urease as thiourea. On the contrary, N-monosubstituted thiourea with a tiny thiourea motif could theoretically bind into the active pocket as thiourea. Objective: A series of N-monosubstituted aroylthioureas were designed and synthesized for evaluation as urease inhibitors. Methods: Urease inhibition was determined by the indophenol method and IC50 values were calculated using computerized linear regression analysis of quantal log dose-probit functions. The kinetic parameters were estimated via surface plasmon resonance (SPR) and by nonlinear regression analysis based on the mixed type inhibition model derived from Michaelis-Menten kinetics. Results: Compounds b2, b11, and b19 reversibly inhibited urease with a mixed mechanism, and showed excellent potency against both cell-free urease and urease in the intact cell, with IC50 values being 90-to 450-fold and 5-to 50-fold lower than the positive control acetohydroxamic acid, respectively. The most potent compound b11 showed an IC50 value of 0.060 ± 0.004μM against cell-free urease, which bound to urea binding site with a very low KD value (0.420±0.003nM) and a very long residence time (6.7 min). Compound b11 was also demonstrated to have very low cytotoxicity to mammalian cells. Conclusion: The results revealed that N-monosubstituted aroylthioureas bound to the active site of urease as expected, and represent a new class of urease inhibitors for the development of potential therapeutics against infections caused by urease-containing pathogens.
Copper-mediated C–H thiolation of (hetero)arenes using weakly coordinating directing group
Wu, Peng,Cheng, Tai-Jin,Lin, Hai-Xia,Xu, Hui,Dai, Hui-Xiong
supporting information, (2020/06/17)
We have developed a copper-mediated C–H thiolation of (hetero)arenes by using monodentate amide as weakly coordinating directing group. This protocol features excellent functional group tolerance and shows satisfactory compatibility with various heterocycles, such as indole, pyrrole, imidazole, pyridine, thiophene and quinoline. The robust nature of this protocol renders that it has potential value in the synthetic application.
Base-promoted Lewis acid catalyzed synthesis of quinazoline derivatives
Cui, Xin-Feng,Hu, Fang-Peng,Huang, Guo-Sheng,Lu, Guo-Qiang
supporting information, p. 4376 - 4380 (2020/10/20)
A one-pot protocol has been developed for the synthesis of quinazolinones from amide-oxazolines with TsCl via a cyclic 1,3-azaoxonium intermediate and 6π electron cyclization in the presence of a Lewis acid and base. The process is operationally simple and has a broad substrate scope. This method provides a unique strategy for the construction of quinazolinones.
Divergent Synthesis of Tunable Cyclopentadienyl Ligands and Their Application in Rh-Catalyzed Enantioselective Synthesis of Isoindolinone
Cui, Wen-Jun,Wu, Zhi-Jie,Gu, Qing,You, Shu-Li
supporting information, p. 7379 - 7385 (2020/08/19)
A series of rhodium complexes bearing sterically and electronically tunable cyclopentadienyl ligands, prepared by utilizing Co2(CO)8-mediated [2+2+1] cyclization as a key step, were synthesized. In the presence of 2.5 mol% of CpmRh4, unprecedented enantioselective [4+1] annulation reaction of benzamides and alkenes was achieved with a broad substrate scope under mild reaction conditions, providing a variety of isoindolinones with excellent regio-and enantioselectivity (up to 94% yield, 97:3 er). Preliminary mechanistic studies suggest that the reaction involves an oxidative Heck reaction and an intramolecular enantioselective alkene hydroamination reaction.
Synthesis of quinazolin-4(1 H)-ones via amination and annulation of amidines and benzamides
Hu, Fangpeng,Cui, Xinfeng,Ban, Zihui,Lu, Guoqiang,Luo, Nan,Huang, Guosheng
supporting information, p. 2356 - 2360 (2019/03/06)
Quinazolinones have broad applications in the biological, pharmaceutical and material fields. Studies on the synthesis of these compounds are therefore widely conducted. Herein, a novel and highly efficient copper-mediated tandem C(sp2)-H amination and annulation of benzamides and amidines for the synthesis of quinazolin-4(1H)-ones is proposed. This synthetic route can be useful for the construction of quinazolin-4(1H)-one frameworks.
