scholarly journals Phenylamino derivatives of tris(2-pyridylmethyl)amine: hydrogen-bonded peroxodicopper complexes

2018 ◽  
Vol 54 (8) ◽  
pp. 892-895 ◽  
Author(s):  
E. W. Dahl ◽  
H. T. Dong ◽  
N. K. Szymczak
Keyword(s):  
Copper Complexes ◽  
Amine Hydrogen ◽  
Amine Ligands ◽  
Derivatives Of ◽  
Hydrogen Bonded

A series of copper complexes bearing new 6-substituted tris(2-pyridylmethyl)amine ligands (LR) appended with NH(p-R-C6H4) groups (R = H, CF3, OMe) were prepared.

Synthesis, characterization and biological activities of 1,3,4-oxadiazole derivatives of nalidixic acid and their copper complexes

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Nalidixic Acid ◽  
Copper Complexes ◽  
Biological Activities ◽  
Bidentate Coordination ◽  
Antibacterial And Antifungal Activities ◽  
Elemental Analyses ◽  
Oxadiazole Derivatives ◽  
Antibacterial And Antifungal ◽  
Derivatives Of ◽  
Substituted 1

A series of novel 1, 3, 4-oxadiazole analogues was synthesized from cyclization of hydrazones of substituted 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carbohydrazides were prepared from nalidixic acid. The structures of synthesized oxadiazole derivatives and their copper complexes were elucidated on the basis of FTIR, elemental analyses, 1H-NMR and atomic absorption spectral analysis. It was observed from spectral data that metal ligand ratio was 1:1 in all copper complexes and they were bidentate, coordination was found to be done through oxygen of 4-oxo group and nitrogen of oxadiazole ring. The synthesized compounds were further evaluated with biological activities and compared with parent hydrazones. Copper complexes possess antibacterial and antifungal activities better than the oxadiazoles while they have better antioxidant activity then copper complexes. Parent hydrazones were better in all biological activities than synthesized oxadiazoles.

scholarly journals Synthesis of new derivatives of copper complexes of Josiphos family ligands for applications in asymmetric catalysis

2014 ◽  
Vol 4 (7) ◽  
pp. 1997-2005 ◽  
Author(s):  
R. Oost ◽  
J. Rong ◽  
A. J. Minnaard ◽  
S. R. Harutyunyan
Keyword(s):  
Asymmetric Catalysis ◽  
Copper Complexes ◽  
Grignard Reagents ◽  
Aromatic Ketones ◽  
Asymmetric Catalytic ◽  
Catalytic Addition ◽  
Derivatives Of

New derivatives of copper complexes of Josiphos family ligands have been prepared and studied in asymmetric catalytic addition of Grignard reagents to enones, enoates and aromatic ketones.

Copper complexes of some amino acid derivatives of substituted coumarilic acid

1992 ◽  
Vol 15 (2) ◽  
pp. 130-133
Author(s):  
Tarek M. Ibrahim ◽  
Ahmed A. Shabana ◽  
Hamdy A. Hammad
Keyword(s):  
Amino Acid ◽  
Copper Complexes ◽  
Amino Acid Derivatives ◽  
Derivatives Of

Thio derivatives of b-diketones and their metal chelates. XXII. Dipole moments of some bivalent and trivalent metal complexes of fluorinated monothio-b-diketones

1976 ◽  
Vol 29 (4) ◽  
pp. 767 ◽  
Author(s):  
M Das ◽  
SE Livingstone ◽  
JH Mayfield ◽  
DS Moore ◽  
N Saha
Keyword(s):  
Copper Complexes ◽  
Dipole Moments ◽  
Platinum Complexes ◽  
Mean Value ◽  
Tetrahedral Configuration ◽  
Square Planar ◽  
Palladium And Platinum Complexes ◽  
Static Polarization ◽  
The Moment ◽  
Derivatives Of

Dipole moments have been determined by static polarization measurements for some iron(111), ruthenium(111), rhodium(111), nickel(11), palladium(11), platinum(11), copper(11) and zinc(11) complexes of fluorinated monothio-β-diketones RC(SH)=CHCOCF3. The moments indicate a facial-octahedral configuration for the iron, ruthenium and rhodium complexes, a cis-square-planar configuration for the nickel, palladium and platinum complexes, and a tetrahedral configuration for the zinc complexes. The copper complexes have moments 0.5-1.0 D lower than the mean value for the corresponding nickel, palladium and platinum complexes; this lowering of the moment is attributed to significant distortion from the square-planar towards the tetrahedral configuration. The dipole moments of the square-planar and octahedral complexes decrease if the R groups are arranged in the order: p-MeC6H4 ≥ 2-thienyl > β-naphthyl > m-MeC6H4 > Ph > Pr? > Bui > Me > m-ClC6H4 > m-BrC6H4 > p-FC6H4 > p-ClC6H4 > p-BrC6H4 > m,p-Cl2C6H3.

Two polymorphs and the diethylammonium salt of the barbiturate eldoral

2012 ◽  
Vol 68 (2) ◽  
pp. o65-o70 ◽  
Author(s):  
Thomas Gelbrich ◽  
Denise Rossi ◽  
Ulrich J. Griesser
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Barbituric Acid ◽  
Layer Structure ◽  
Chain Structure ◽  
Hydrogen Bond Acceptor ◽  
Layer Structures ◽  
A Chain ◽  
Derivatives Of ◽  
Hydrogen Bonded

Polymorph (Ia) of eldoral [5-ethyl-5-(piperidin-1-yl)barbituric acid or 5-ethyl-5-(piperidin-1-yl)-1,3-diazinane-2,4,6-trione], C11H17N3O3, displays a hydrogen-bonded layer structure parallel to (100). The piperidine N atom and the barbiturate carbonyl group in the 2-position are utilized in N—H...N and N—H...O=C hydrogen bonds, respectively. The structure of polymorph (Ib) contains pseudosymmetry elements. The two independent molecules of (Ib) are connectedviaN—H...O=C(4/6-position) and N—H...N(piperidine) hydrogen bonds to give a chain structure in the [100] direction. The hydrogen-bonded layers, parallel to (010), formed in the salt diethylammonium 5-ethyl-5-(piperidin-1-yl)barbiturate [or diethylammonium 5-ethyl-2,4,6-trioxo-5-(piperidin-1-yl)-1,3-diazinan-1-ide], C4H12N+·C11H16N3O3−, (II), closely resemble the corresponding hydrogen-bonded structure in polymorph (Ia). Like many other 5,5-disubstituted derivatives of barbituric acid, polymorphs (Ia) and (Ib) contain theR22(8) N—H...O=C hydrogen-bond motif. However, the overall hydrogen-bonded chain and layer structures of (Ia) and (Ib) are unique because of the involvement of the hydrogen-bond acceptor function in the piperidine group.

Molecular recognition XI. The synthesis of extensively deoxygenated derivatives of the H-type 2 human blood group determinant and their binding by an anti-H-type 2 monoclonal antibody and the lectin 1 of Ulexeuropaeus

1992 ◽  
Vol 70 (1) ◽  
pp. 254-271 ◽  
Author(s):  
Ulrike Spohr ◽  
Eugenia Paszkiewicz-Hnatiw ◽  
Naohiko Morishima ◽  
Raymond U. Lemieux
Keyword(s):  
Monoclonal Antibody ◽  
Molecular Recognition ◽  
Blood Group ◽  
Human Blood ◽  
Water Molecules ◽  
Hydroxyl Groups ◽  
Human Blood Group ◽  
Derivatives Of ◽  
Hydrogen Bonded

The relative potencies of a wide variety of deoxygenated derivatives of the methyl glycoside of α-L-Fuc-(1 → 2)-β-D-Gal-(1 → 4)- β-D-GlcNAc (the H-type 2 human blood group related trisaccharide) for the inhibition of the binding of an artificial H-type 2 antigen by the lectin I of Ulexeuropaeus confirmed the previous evidence that the key and productive interaction involves only the three hydroxyl groups of the α-L-fucose unit, the hydroxyl at the 3-position of the β-D-galactose residue, and the nonpolar groups in their immediate environment. Except for the acetamido group and the hydroxymethyl of the β-D-Gal unit, which stay in the aqueous phase, on complex formation the remaining three hydroxyl groups appear to come to reside at or near the periphery of the combining site since their replacement by hydrogen causes relatively small changes (< ± 1 kcal/mol) in the stability of the complex (ΔG0). Relatively much larger but compensating changes occur for the enthalpy and entropy terms, and these may arise primarily from the differences in the water structure about the periphery of the combining site and the oligosaccharide both prior to and after complexation. It is proposed that steric constraints lead to an ordered state of the water molecules hydrogen-bonded to the polar groups within the cleft formed by the key region of the amphiphilic combining site. Their release to form less ordered clusters of more strongly hydrogen-bonded water molecules in bulk solution would contribute importantly to the driving force for complexation. It is demonstrated that the surface used for the binding of H-type 2-OMe by a monoclonal anti-H antibody is virtually identical to that used by the Ulex lectin. Keywords: molecular recognition, H-type 2 blood group determinant and deoxygenated derivatives, lectin I of Ulexeuropaeus, anti-H-type 2 monoclonal antibody, enthalpy–entropy compensation.

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