An Efficient, Ligand-Free, Heterogeneous Supported Copper Hydroxide Catalyst for the Synthesis of N,N-Bicyclic Pyrazolidinone Derivatives

Kazuaki Yoshimura; Takamichi Oishi; Kazuya Yamaguchi; Noritaka Mizuno

doi:10.1002/chem.201002793

ChemInform Abstract: An Efficient, Ligand-Free, Heterogeneous Supported Copper Hydroxide Catalyst for the Synthesis of N,N-Bicyclic Pyrazolidinone Derivatives.

ChemInform ◽

10.1002/chin.201128118 ◽

2011 ◽

Vol 42 (28) ◽

pp. no-no

Author(s):

Kazuaki Yoshimura ◽

Takamichi Oishi ◽

Kazuya Yamaguchi ◽

Noritaka Mizuno

Keyword(s):

Copper Hydroxide ◽

Ligand Free

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A Supported Copper Hydroxide as an Efficient, Ligand-free, and Heterogeneous Precatalyst for 1,3-Dipolar Cycloadditions of Organic Azides to Terminal Alkynes

ChemSusChem ◽

10.1002/cssc.200800202 ◽

2009 ◽

Vol 2 (1) ◽

pp. 59-62 ◽

Cited By ~ 53

Author(s):

Tatsuyori Katayama ◽

Keigo Kamata ◽

Kazuya Yamaguchi ◽

Noritaka Mizuno

Keyword(s):

Terminal Alkynes ◽

Copper Hydroxide ◽

Dipolar Cycloadditions ◽

Organic Azides ◽

Ligand Free

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CarR, a MarR-family regulator from Corynebacterium glutamicum, modulated antibiotic and aromatic compound resistance

Biochemical Journal ◽

10.1042/bcj20190320 ◽

2019 ◽

Vol 476 (21) ◽

pp. 3141-3159 ◽

Cited By ~ 2

Author(s):

Meiru Si ◽

Can Chen ◽

Zengfan Wei ◽

Zhijin Gong ◽

GuiZhi Li ◽

...

Keyword(s):

Stress Response ◽

Ligand Binding ◽

Corynebacterium Glutamicum ◽

Conformational Changes ◽

Cysteine Oxidation ◽

Transcriptional Regulatory ◽

Ligand Free ◽

Redox Sensing

Abstract MarR (multiple antibiotic resistance regulator) proteins are a family of transcriptional regulators that is prevalent in Corynebacterium glutamicum. Understanding the physiological and biochemical function of MarR homologs in C. glutamicum has focused on cysteine oxidation-based redox-sensing and substrate metabolism-involving regulators. In this study, we characterized the stress-related ligand-binding functions of the C. glutamicum MarR-type regulator CarR (C. glutamicum antibiotic-responding regulator). We demonstrate that CarR negatively regulates the expression of the carR (ncgl2886)–uspA (ncgl2887) operon and the adjacent, oppositely oriented gene ncgl2885, encoding the hypothetical deacylase DecE. We also show that CarR directly activates transcription of the ncgl2882–ncgl2884 operon, encoding the peptidoglycan synthesis operon (PSO) located upstream of carR in the opposite orientation. The addition of stress-associated ligands such as penicillin and streptomycin induced carR, uspA, decE, and PSO expression in vivo, as well as attenuated binding of CarR to operator DNA in vitro. Importantly, stress response-induced up-regulation of carR, uspA, and PSO gene expression correlated with cell resistance to β-lactam antibiotics and aromatic compounds. Six highly conserved residues in CarR were found to strongly influence its ligand binding and transcriptional regulatory properties. Collectively, the results indicate that the ligand binding of CarR induces its dissociation from the carR–uspA promoter to derepress carR and uspA transcription. Ligand-free CarR also activates PSO expression, which in turn contributes to C. glutamicum stress resistance. The outcomes indicate that the stress response mechanism of CarR in C. glutamicum occurs via ligand-induced conformational changes to the protein, not via cysteine oxidation-based thiol modifications.

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Copper-Catalyzed Hydrocarboxylation of Allenes

10.26434/chemrxiv.7862456.v1 ◽

2019 ◽

Author(s):

Rémi blieck ◽

Marc Taillefer ◽

Florian Monnier

Keyword(s):

Carboxylic Acids ◽

Copper Catalysis ◽

Ligand Free ◽

First Time

The addition of carboxylic acids to allenes was performed for the first time with copper catalysis. The hydrocarboxylation reaction is totally regio- and stereoselective, ligand-free and used catalytic amounts of copper and base.

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Tris(pyrazolyl)borate Copper Hydroxide Complexes Featuring Tunable Intramolecular H-bonding

10.26434/chemrxiv.7878065.v1 ◽

2019 ◽

Author(s):

Evan Gardner ◽

Caitlyn Cobb ◽

Jeffery A. Bertke ◽

Timothy H. Warren

Keyword(s):

Single Crystal ◽

Copper Hydroxide ◽

X Ray ◽

Modular Synthesis ◽

Pendant Arm ◽

Copper Center ◽

Vibrational Studies

A modular synthesis provides access to a series of new tris(pyrazolyl)borate ligands XpyMeTpK that possess a single functionalized pendant pyridyl (py) or pyrimidyl (pyd) arm designed to engage in tunable intramolecular H-bonding to metal–bound functionalities. To illustrate such H-bonding interactions, a series of [XpyMeTpCu]2(𝜇–OH)2(6a–6e) complexes were synthesized from the corresponding XpyMeTpCu–OAc (5a–5e) complexes. Single crystal X-ray structures of three new dinuclear [XpyMeTpCu]2(𝜇–OH)2complexes reveal H-bonding between the pendant heterocycle and bridging hydroxide ligands while the donor arm engages the copper center in an unusual monomeric DMAPMeTpCu–OH complex. Vibrational studies (IR) of each bridging hydroxide complex reveal reduced 𝜈OH frequencies that tracks with the H-bond accepting ability of the pendant arm.

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Tris(pyrazolyl)borate Copper Hydroxide Complexes Featuring Tunable Intramolecular H-bonding

10.26434/chemrxiv.7878065 ◽

2019 ◽

Author(s):

Evan Gardner ◽

Caitlyn Cobb ◽

Jeffery A. Bertke ◽

Timothy H. Warren

Keyword(s):

Single Crystal ◽

Copper Hydroxide ◽

X Ray ◽

Modular Synthesis ◽

Pendant Arm ◽

Copper Center ◽

Vibrational Studies

A modular synthesis provides access to a series of new tris(pyrazolyl)borate ligands XpyMeTpK that possess a single functionalized pendant pyridyl (py) or pyrimidyl (pyd) arm designed to engage in tunable intramolecular H-bonding to metal–bound functionalities. To illustrate such H-bonding interactions, a series of [XpyMeTpCu]2(𝜇–OH)2(6a–6e) complexes were synthesized from the corresponding XpyMeTpCu–OAc (5a–5e) complexes. Single crystal X-ray structures of three new dinuclear [XpyMeTpCu]2(𝜇–OH)2complexes reveal H-bonding between the pendant heterocycle and bridging hydroxide ligands while the donor arm engages the copper center in an unusual monomeric DMAPMeTpCu–OH complex. Vibrational studies (IR) of each bridging hydroxide complex reveal reduced 𝜈OH frequencies that tracks with the H-bond accepting ability of the pendant arm.

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