Theoretical analysis of apical bonding in copper(II) chelates withN-substituted amino acids

The interdependence between the side of apical coordination of H2O and steric crowding at the apical positions was investigated on a set of 34 copper(II) bis-complexes withN- andN,N-substituted amino acids. As a measure of steric crowding, overlapping volumesV* were used, calculated using a modified overlapping spheres method. Steric crowding around the apically bonded ligand was the same for this set of complexes as for the copper(II) bis-complexes with naturally occurring amino acids, with the optimal occupied volume values between 1 and 1.5 Å3. The interdependence between the length of the apical bond and distortion of the coordination polyhedron was also studied. The apical bond length showed sigmoidal dependence on the magnitude of distortion.

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Theoretical analysis of apical bonding in copper(II) chelates with amino acids

Journal of Applied Crystallography ◽

10.1107/s0021889809023589 ◽

2009 ◽

Vol 42 (5) ◽

pp. 793-797 ◽

Cited By ~ 1

Author(s):

Ante Miličević ◽

Nenad Raos

Keyword(s):

Amino Acids ◽

Theoretical Analysis ◽

Bond Length ◽

Dimethyl Sulfoxide ◽

Coordination Polyhedron ◽

Side Chain ◽

Naturally Occurring ◽

Steric Crowding ◽

Overlapping Spheres

The interdependence between the side of apical coordination (H2O, >C=O, dimethyl sulfoxide and Cl−) and steric crowding at the apical positions was investigated for a set of 20 copper(II) bis complexes with naturally occurring amino acids. As a measure of steric crowding the overlapping volumes,V*, were used, calculated by the modified overlapping spheres method. It was found that the apically coordinated side of a complex is more hindered by the side-chain atoms. In addition, if both sides are apically coordinated, the apical bond is shorter at the more crowded side. The interdependence between the length of the apical bond and distortion of the coordination polyhedron was also studied. The apical bond length shows sigmoidal dependence on the magnitude of distortion, and is also dependent on the kind of distortion (square-pyramidal or tetrahedral).

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A note on the distortion theorem

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s205252061700912x ◽

2017 ◽

Vol 73 (5) ◽

pp. 874-878

Author(s):

M. S. Nickolsky

Keyword(s):

Theoretical Analysis ◽

Bond Length ◽

Coordination Polyhedron ◽

Distortion Theorem ◽

Bond Valence ◽

Conditional Statement ◽

The Mean

The distortion theorem is a conditional statement that establishes the certain relations between the variation of the mean bond length and the variation of the valence of a central ion of a coordination polyhedron. It was found that in some principal cases the conditional part of the distortion theorem is not necessary. A combinatorial evaluation of the distortion theorem and a theoretical analysis of the bond length–bond valence correlation were performed. An extension of the distortion theorem is proposed.

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Chelates of copper(II) with N-alkylated amino acids: distortion of coordination polyhedron and apical bond length

Journal of Molecular Structure ◽

10.1016/0022-2860(95)08900-g ◽

1995 ◽

Vol 355 (2) ◽

pp. 211-218 ◽

Cited By ~ 4

Author(s):

Nenad Raos

Keyword(s):

Amino Acids ◽

Bond Length ◽

Coordination Polyhedron

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THEORETICAL ANALYSIS OF THE STRUCTURE AND VIBRATIONAL SPECTR OF ASPARAGINE AND GLUTAMIC AMINO ACIDS IN WATER AT DIFFERENT pH

NATURAL SCIENCES ◽

10.21672/1818-507x-2017-60-3-094-107 ◽

2017 ◽

Vol 60 (3) ◽

pp. 094-107

Author(s):

Galina N. Ten ◽

◽

N.E. Shcherbakova ◽

Viktor I. Baranov ◽

◽

...

Keyword(s):

Amino Acids ◽

Theoretical Analysis

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Helix-Coil Stability for the Naturally Occurring Amino Acids in Water. VIII. Valine Parameters from Random Poly(hydroxypropylglutamine-co-L-valine) and Poly(hydroxybutylglutamine-co-L-valine)

Macromolecules ◽

10.1021/ma60034a019 ◽

1973 ◽

Vol 6 (4) ◽

pp. 564-570 ◽

Cited By ~ 43

Author(s):

J. E. Alter ◽

R. H. Andreatta ◽

G. T. Taylor ◽

H. A. Scheraga

Keyword(s):

Amino Acids ◽

Naturally Occurring

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Regulation of rat magnocellular neurosecretory system by D-aspartate: evidence for biological role(s) of a naturally occurring free D-amino acid in mammals

Journal of Endocrinology ◽

10.1677/joe.0.1670247 ◽

2000 ◽

Vol 167 (2) ◽

pp. 247-252 ◽

Cited By ~ 57

Author(s):

H Wang ◽

H Wolosker ◽

J Pevsner ◽

SH Snyder ◽

DJ Selkoe

Keyword(s):

Gene Expression ◽

Amino Acids ◽

Amino Acid ◽

Physiological Function ◽

Neurosecretory System ◽

Milk Ejection ◽

Magnocellular Neurons ◽

Rat Hypothalamus ◽

Naturally Occurring

Little evidence is available for the physiological function of D-amino acids in species other than bacteria. Here we demonstrate that naturally occurring freed -aspartate (D-Asp) is present in all magnocellular neurons of rat hypothalamus. The levels of this naturally occurring D-amino acid were elevated during lactation and returned to normal thereafter in the magnocellular neurosecretory system, which produces oxytocin, a hormone responsible for milk ejection during lactation. Intraperitoneal injections of D-Asp reproducibly increased oxytocin gene expression and decreased the concentration of circulating oxytocin in vivo. Similar changes were observed in the vasopressin system. These results provide evidence for the role(s) of naturally occurring free D-Asp in mammalian physiology. The findings argue against the conventional concept that only L-stereoisomers of amino acids are functional in higher species.

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