Inside Cover: Beryllium Complexes with Bio-Relevant Functional Groups: Coordination Geometries and Binding Affinities (Angew. Chem. Int. Ed. 29/2018)

We report on the synthesis and characterization of novel shape-persistent, optically active arylamide macrocycles, which can be obtained using a one-pot methodology. Resolved, axially chiral binol scaffolds, which incorporate either methoxy or acetoxy functionalities in the 2,2' positions and carboxylic functionalities in the external 3,3' positions, were used as the source of chirality. Two of these binaphthyls are joined through amidation reactions using rigid diaryl amines of differing shapes, to give homochiral tetraamidic macrocycles. The recognition properties of these supramolecular receptors have been analyzed, and the results indicate a modulation of binding affinities towards dicarboxylate anions, with a drastic change of binding mode depending on the steric and electronic features of the functional groups in the 2,2' positions.

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Specificity determinants of phosphoprotein phosphatases controlling kinetochore functions

Essays in Biochemistry ◽

10.1042/ebc20190065 ◽

2020 ◽

Vol 64 (2) ◽

pp. 325-336 ◽

Cited By ~ 1

Author(s):

Dimitriya H. Garvanska ◽

Jakob Nilsson

Keyword(s):

Spindle Assembly Checkpoint ◽

Activity Level ◽

Phosphorylation Sites ◽

Binding Affinities ◽

Mitotic Kinases ◽

Anaphase Onset ◽

Phosphoprotein Phosphatases ◽

Linear Motifs ◽

Temporal And Spatial ◽

Kinetochore Function

Abstract Kinetochores are instrumental for accurate chromosome segregation by binding to microtubules in order to move chromosomes and by delaying anaphase onset through the spindle assembly checkpoint (SAC). Dynamic phosphorylation of kinetochore components is key to control these activities and is tightly regulated by temporal and spatial recruitment of kinases and phosphoprotein phosphatases (PPPs). Here we focus on PP1, PP2A-B56 and PP2A-B55, three PPPs that are important regulators of mitosis. Despite the fact that these PPPs share a very similar active site, they target unique ser/thr phosphorylation sites to control kinetochore function. Specificity is in part achieved by PPPs binding to short linear motifs (SLiMs) that guide their substrate specificity. SLiMs bind to conserved pockets on PPPs and are degenerate in nature, giving rise to a range of binding affinities. These SLiMs control the assembly of numerous substrate specifying complexes and their position and binding strength allow PPPs to target specific phosphorylation sites. In addition, the activity of PPPs is regulated by mitotic kinases and inhibitors, either directly at the activity level or through affecting PPP–SLiM interactions. Here, we discuss recent progress in understanding the regulation of PPP specificity and activity and how this controls kinetochore biology.

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Improving integration between functional groups: A case in organization change and implications for theory and practice

PsycEXTRA Dataset ◽

10.1037/e611322012-293 ◽

1971 ◽

Author(s):

Warren G. Bennis ◽

Michael Beer ◽

Gerald R. Pieters ◽

Alan T. Hundert ◽

Samuel H. Marcus ◽

...

Keyword(s):

Functional Groups ◽

Organization Change ◽

Theory And Practice

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HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

Dentika Dental Journal ◽

10.32734/dentika.v19i2.457 ◽

2016 ◽

Vol 19 (2) ◽

pp. 93-100

Author(s):

Lalita El Milla

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Functional Groups ◽

Bone Growth ◽

Three Dimensional ◽

Dimensional Structure ◽

Tissue Engineering Scaffolds ◽

Hydroxyapatite Powder ◽

Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

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Investigation of the Nature of Functional Groups of Graphene Membranes by Means of IR Spectroscopy

Химия в интересах устойчивого развития ◽

10.15372/khur2020255 ◽

2020 ◽

Keyword(s):

Ir Spectroscopy ◽

Functional Groups ◽

Graphene Membranes

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High Resolution Displacement of Functional Groups onto Fluorocarbon Resin Surface by Using ArF Excimer Laser

MRS Proceedings ◽

10.1557/proc-451-521 ◽

1996 ◽

Vol 451 ◽

Cited By ~ 1

Author(s):

T. Shimizu ◽

M. Murahara

Keyword(s):

Contact Angle ◽

High Resolution ◽

Laser Beam ◽

Thin Layer ◽

Functional Groups ◽

Excimer Laser ◽

Laser Fluence ◽

Large Area ◽

Three Solutions ◽

Arf Excimer Laser

ABSTRACTA Fluorocarbon resin surface was selectively modified by irradiation with a ArF laser beam through a thin layer of NaAlO2, B(OH)3, or H2O solution to give a hydrophilic property. As a result, with low fluence, the surface was most effectively modified with the NaAlO2 solution among the three solutions. However, the contact angle in this case changed by 10 degrees as the fluence changed only 1mJ/cm2. When modifying a large area of the surface, high resolution displacement could not be achieved because the laser beam was not uniform in displacing functional groups. Thus, the laser fluence was successfully made uniform by homogenizing the laser beam; the functional groups were replaced on the fluorocarbon resin surface with high resolution, which was successfully modified to be hydrophilic by distributing the laser fluence uniformly.

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Visible Light-Promoted Catalytic Ring-Opening Isomerization of 1,2-Disubstituted Cyclopropanols to Linear Ketones

10.26434/chemrxiv.11467845.v1 ◽

2019 ◽

Author(s):

Marharyta V. Laktsevich-Iskryk ◽

Nastassia A. Varabyeva ◽

Volha V. Kazlova ◽

Vladimir N. Zhabinskii ◽

Vladimir A. Khripach ◽

...

Keyword(s):

Visible Light ◽

Functional Groups ◽

Ring Opening ◽

Radical Intermediates ◽

Reaction Proceeds

In this article, we report a photocatalytic protocol for the isomerization of 1,2-disubstituted cyclopropanols to linear ketones. The reaction proceeds via radical intermediates and tolerates various functional groups.

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Visible Light-Promoted Catalytic Ring-Opening Isomerization of 1,2-Disubstituted Cyclopropanols to Linear Ketones

10.26434/chemrxiv.11467845 ◽

2019 ◽

Author(s):

Marharyta V. Laktsevich-Iskryk ◽

Nastassia A. Varabyeva ◽

Volha V. Kazlova ◽

Vladimir N. Zhabinskii ◽

Vladimir A. Khripach ◽

...

Keyword(s):

Visible Light ◽

Functional Groups ◽

Ring Opening ◽

Radical Intermediates ◽

Reaction Proceeds

In this article, we report a photocatalytic protocol for the isomerization of 1,2-disubstituted cyclopropanols to linear ketones. The reaction proceeds via radical intermediates and tolerates various functional groups.

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Automated Assessment of Binding Affinity via Alchemical Free Energy Calculations

10.26434/chemrxiv.11812053.v1 ◽

2020 ◽

Author(s):

Maximilian Kuhn ◽

Stuart Firth-Clark ◽

Paolo Tosco ◽

Antonia S. J. S. Mey ◽

Mark Mackey ◽

...

Keyword(s):

Free Energy ◽

Protein Structures ◽

Free Energy Calculations ◽

Distinct Advantage ◽

Binding Affinities ◽

Structure Based Drug Design ◽

Energy Calculations ◽

Kendall’S Τ ◽

Experimental Values ◽

Better Than

Free energy calculations have seen increased usage in structure-based drug design. Despite the rising interest, automation of the complex calculations and subsequent analysis of their results are still hampered by the restricted choice of available tools. In this work, an application for automated setup and processing of free energy calculations is presented. Several sanity checks for assessing the reliability of the calculations were implemented, constituting a distinct advantage over existing open-source tools. The underlying workflow is built on top of the software Sire, SOMD, BioSimSpace and OpenMM and uses the AMBER14SB and GAFF2.1 force fields. It was validated on two datasets originally composed by Schrödinger, consisting of 14 protein structures and 220 ligands. Predicted binding affinities were in good agreement with experimental values. For the larger dataset the average correlation coefficient Rp was 0.70 ± 0.05 and average Kendall’s τ was 0.53 ± 0.05 which is broadly comparable to or better than previously reported results using other methods.

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