C,C- and C,N-Chelated Organocopper Compounds

Copper-catalyzed and organocopper-involved reactions are of great significance in organic synthesis. To have a deep understanding of the reaction mechanisms, the structural characterizations of organocopper intermediates become indispensable. Meanwhile, the structure-function relationship of organocopper compounds could advance the rational design and development of new Cu-based reactions and organocopper reagents. Compared to the mono-carbonic ligand, the C,N- and C,C-bidentate ligands better stabilize unstable organocopper compounds. Bidentate ligands can chelate to the same copper atom via η2-mode, forming a mono-cupra-cyclic compounds with at least one acute C-Cu-C angle. When the bidentate ligands bind to two copper atoms via η1-mode at each coordinating site, the bimetallic macrocyclic compounds will form nearly linear C-Cu-C angles. The anionic coordinating sites of the bidentate ligand can also bridge two metals via μ2-mode, forming organocopper aggregates with Cu-Cu interactions and organocuprates with contact ion pair structures. The reaction chemistry of some selected organocopper compounds is highlighted, showing their unique structure–reactivity relationships.

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Rational Design of Artificial Metalloproteins and Metalloenzymes with Metal Clusters

Molecules ◽

10.3390/molecules24152743 ◽

2019 ◽

Vol 24 (15) ◽

pp. 2743 ◽

Cited By ~ 6

Author(s):

Ying-Wu Lin

Keyword(s):

Active Sites ◽

Rational Design ◽

Metal Clusters ◽

De Novo ◽

Deep Understanding ◽

Zinc Clusters ◽

Synthetic Metal ◽

Function Relationship ◽

Structure And Function Relationship ◽

And Function

Metalloproteins and metalloenzymes play important roles in biological systems by using the limited metal ions, complexes, and clusters that are associated with the protein matrix. The design of artificial metalloproteins and metalloenzymes not only reveals the structure and function relationship of natural proteins, but also enables the synthesis of artificial proteins and enzymes with improved properties and functions. Acknowledging the progress in rational design from single to multiple active sites, this review focuses on recent achievements in the design of artificial metalloproteins and metalloenzymes with metal clusters, including zinc clusters, cadmium clusters, iron–sulfur clusters, and copper–sulfur clusters, as well as noble metal clusters and others. These metal clusters were designed in both native and de novo protein scaffolds for structural roles, electron transfer, or catalysis. Some synthetic metal clusters as functional models of native enzymes are also discussed. These achievements provide valuable insights for deep understanding of the natural proteins and enzymes, and practical clues for the further design of artificial enzymes with functions comparable or even beyond those of natural counterparts.

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Structure–property–function relationship of fluorescent conjugated microporous polymers

Materials Chemistry Frontiers ◽

10.1039/d0qm00769b ◽

2021 ◽

Author(s):

M. G. Monika Bai ◽

H. Vignesh Babu ◽

V. Lakshmi ◽

M. Rajeswara Rao

Keyword(s):

Long Range ◽

Structure Property ◽

Porous Organic Polymers ◽

Aggregation Induced Emission ◽

Microporous Polymers ◽

Exciton Migration ◽

Wide Range ◽

Function Relationship ◽

Relationship Of ◽

Conjugated Microporous Polymers

Fluorescent porous organic polymers are a unique class of materials owing to their strong aggregation induced emission, long range exciton migration and permanent porosity, thus envisioned to possess a wide range of applications (sensing, OLEDs).

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Structure-Acid Lability Relationship of N-alkylated α,α-dialkylglycine Obtained via a Ugi Multicomponent Reaction

Molecules ◽

10.3390/molecules26010197 ◽

2021 ◽

Vol 26 (1) ◽

pp. 197

Author(s):

Iván Ramos-Tomillero ◽

Marisa K. Sánchez ◽

Hortensia Rodríguez ◽

Fernando Albericio

Keyword(s):

Solid Phase Synthesis ◽

Solid Phase ◽

Structural Features ◽

Amide Bond ◽

Acidic Media ◽

Phase Synthesis ◽

Acyl Chains ◽

Cyclic Compounds ◽

Relationship Of ◽

Fine Tune

Using the classical Ugi four-component reaction to fuse an amine, ketone, carboxylic acid, and isocyanide, here we prepared a short library of N-alkylated α,α-dialkylglycine derivatives. Due to the polyfunctionality of the dipeptidic scaffold, this highly steric hindered system shows an interesting acidolytic cleavage of the C-terminal amide. In this regard, we studied the structure-acid lability relationship of the C-terminal amide bond (cyclohexylamide) of N-alkylated α,α-dialkylglycine amides 1a–n in acidic media and, afterward, it was established that the most important structural features related to its cleavage. Then, it was demonstrated that electron-donating effects in the aromatic amines, flexible acyl chains (Gly) at the N-terminal and the introduction of cyclic compounds into dipeptide scaffolds, increased the rate of acidolysis. All these effects are related to the ease with which the oxazolonium ion intermediate forms and they promote the proximity of the central carbonyl group to the C-terminal amide, resulting in C-terminal amide cleavage. Consequently, these findings could be applied for the design of new protecting groups, handles for solid-phase synthesis, and linkers for conjugation, due to its easily modulable and the fact that it allows to fine tune its acid-lability.

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Structure-Function Relationship of Human Parathyroid Hormone on Vitamin D Receptor Regulation in Osteoblast-Like Cells (ROS 17/2.8)

Vitamin D ◽

10.1515/9783110882513-085 ◽

1994 ◽

pp. 245-246

Keyword(s):

Vitamin D ◽

Parathyroid Hormone ◽

Structure Function ◽

Vitamin D Receptor ◽

Receptor Regulation ◽

Human Parathyroid Hormone ◽

Structure Function Relationship ◽

Function Relationship ◽

Relationship Of

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Morphology-Function Relationship of Thermoelectric Nanocomposite Films from PEDOT:PSS with Silicon Nanoparticles

Advanced Electronic Materials ◽

10.1002/aelm.201700181 ◽

2017 ◽

Vol 3 (8) ◽

pp. 1700181 ◽

Cited By ~ 27

Author(s):

Nitin Saxena ◽

Mihael Čorić ◽

Anton Greppmair ◽

Jan Wernecke ◽

Mika Pflüger ◽

...

Keyword(s):

Silicon Nanoparticles ◽

Nanocomposite Films ◽

Function Relationship ◽

Relationship Of

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High-resolution single-cell 3D-models of chromatin ensembles during Drosophila embryogenesis

Nature Communications ◽

10.1038/s41467-020-20490-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Qiu Sun ◽

Alan Perez-Rathke ◽

Daniel M. Czajkowsky ◽

Zhifeng Shao ◽

Jie Liang

Keyword(s):

High Resolution ◽

Single Cell ◽

3D Models ◽

Computational Method ◽

Midblastula Transition ◽

Genome Wide ◽

Large Ensembles ◽

Chromatin Folding ◽

Function Relationship ◽

Relationship Of

AbstractSingle-cell chromatin studies provide insights into how chromatin structure relates to functions of individual cells. However, balancing high-resolution and genome wide-coverage remains challenging. We describe a computational method for the reconstruction of large 3D-ensembles of single-cell (sc) chromatin conformations from population Hi-C that we apply to study embryogenesis in Drosophila. With minimal assumptions of physical properties and without adjustable parameters, our method generates large ensembles of chromatin conformations via deep-sampling. Our method identifies specific interactions, which constitute 5–6% of Hi-C frequencies, but surprisingly are sufficient to drive chromatin folding, giving rise to the observed Hi-C patterns. Modeled sc-chromatins quantify chromatin heterogeneity, revealing significant changes during embryogenesis. Furthermore, >50% of modeled sc-chromatin maintain topologically associating domains (TADs) in early embryos, when no population TADs are perceptible. Domain boundaries become fixated during development, with strong preference at binding-sites of insulator-complexes upon the midblastula transition. Overall, high-resolution 3D-ensembles of sc-chromatin conformations enable further in-depth interpretation of population Hi-C, improving understanding of the structure-function relationship of genome organization.

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