7-Methyl-6-furylpurine forms dinuclear metal complexes with N3,N9 coordination

2018 ◽  
Vol 73 (11) ◽  
pp. 813-817 ◽  
Author(s):  
Indranil Sinha ◽  
Lukas Heller ◽  
Jutta Kösters ◽  
Jens Müller
Keyword(s):  
Metal Ions ◽  
Metal Complexes ◽  
Metal Ion ◽  
Dinuclear Complexes ◽  
Purine Derivatives ◽  
Purine Derivative ◽  
Coordination Environment ◽  
Bridging Ligand ◽  
Dinuclear Metal Complexes ◽  
Argentophilic Interaction

AbstractTwo dinuclear metal complexes bearing the purine derivative 7-methyl-6-furylpurine (1b) as a ligand are reported. In [Ag2(1b)2(DMSO)2](ClO4)2·DMSO and [Cu2(1b)2(NO3)2], two bridging purine derivatives coordinate the two metal ions via their N3 and N9 positions. In the silver(I) complex, the coordination environment of each metal ion is completed by a DMSO ligand, whereas an additional nitrato ligand coordinates to each copper(I) ion. The intramolecular Ag···Ag distance of 3.1069(5) Å is in agreement with the presence of a weak argentophilic interaction, whereas the Cu···Cu distance of 2.9382(4) Å is too long to be indicative of a cuprophilic interaction. The compounds represent the first examples of dinuclear complexes comprising two N3,N9-bridging purine derivatives without any additional bridging ligand.

scholarly journals Synthesis and Spectral Analysis of Some Metal Ions Complexes with Mixed Ligands of Schiff Base and 1, 10-Phenanthroline

2017 ◽  
Vol 14 (1) ◽  
pp. 135-147
Author(s):  
Baghdad Science Journal
Keyword(s):  
Schiff Base ◽  
Metal Ions ◽  
Metal Complexes ◽  
Mass Spectrometer ◽  
Schiff Base Ligand ◽  
Metal Ion ◽  
Molecular Structures ◽  
Spectroscopic Techniques ◽  
Metal Ion Complexes ◽  
Free Schiff Base

The free Schiff base ligand (HL1) is prepared by being mixed with the co-ligand 1, 10-phenanthroline (L2). The product then is reacted with metal ions: (Cr+3, Fe+3, Co+2, Ni+2, Cu+2 and Cd+2) to get new metal ion complexes. The ligand is prepared and its metal ion complexes are characterized by physic-chemical spectroscopic techniques such as: FT-IR, UV-Vis, spectra, mass spectrometer, molar conductivity, magnetic moment, metal content, chloride content and microanalysis (C.H.N) techniques. The results show the formation of the free Schiff base ligand (HL1). The fragments of the prepared free Schiff base ligand are identified by the mass spectrometer technique. All the analysis of ligand and its metal complexes are in good agreement with the theoretical values indicating the purity of Schiff base ligand and the metal complexes. From the above data, the molecular structures for all the metal complexes are proposed to be octahedral

Synthesis of Some Novel Dinuclear Metal Complexes, Containing Both Square-Planar and Tetrahedral Metal Ions, by the Reactions of Coordinated Diamines with an α-Hydroxy Ketone

1985 ◽  
Vol 38 (9) ◽  
pp. 1319 ◽  
Author(s):  
TE MacDermott
Keyword(s):  
Metal Ions ◽  
Metal Complexes ◽  
Hydroxy Ketone ◽  
Square Planar ◽  
Dinuclear Metal Complexes

Reactions between tris (propane-1,3-diamine)nickel(II) salts and 3- hydroxy-3-methylbutan-2-one in the presence of zinc(II) or cadmium(II) halides yield a series of di -oxygen-bridged dinuclear products which contain the square-planar nickel(II) complex of a 12-membered ligand ring one of whose members is either a zinc(II) or cadmium(II) halide. These complexes are thermally very stable but may be hydrolysed by water to give a complex of the corresponding α- imino alcohol.

Collision-Induced Dissociation Studies of Alkali Metal Adducts of Tetracyclines and Anti-Viral Agents by Electrospray Ionization, Hydrogen/Deuterium Exchange and Multiple Stage Mass Spectrometry

2008 ◽  
Vol 14 (5) ◽  
pp. 281-297 ◽  
Author(s):  
Amin Kamel ◽  
Burnaby Munson
Keyword(s):  
Metal Ions ◽  
Metal Complexes ◽  
Metal Ion ◽  
Mass Spectra ◽  
Collision Induced Dissociation ◽  
Guanine Derivatives ◽  
Product Ions ◽  
Hydrogen Deuterium ◽  
Cleavage Reactions ◽  
Metal Adducts

The collision-induced dissociation (CID) mass spectra were obtained for the X+-adducts (X = Na+ or Li+) of five tetracyclines, four pyrimidine and three purine derivatives and their fully D-exchanged species in which the labile hydrogens were replaced by deuterium by either gas- or liquid-phase exchange. The CID spectra were obtained for [M + Na]+ and [M + Li]+ and the exchanged analogs, [M(D) + Na]+ and [M(D) + Li]+, and compositions of product ions and mechanisms of decomposition were determined by comparison of the MS n spectra of the undeuterated and deuterated species. Metal ions are bound to the base of purine and pyrimidine anti-viral agents and dissociate primarily to give the metal complexes of the base [B + X]+. For vidarabine monophosphate, however, the metal ions are bound to the phosphate group, resulting in unique and characteristic cleavage reactions not observed in the uncomplexed system and dissociate through the loss of phosphate and/or a phosphate metal ion complex. The [B + X]+ of these anti-viral agents are relatively stable and show little or no fragmentation compared to [B + H]+. The CID of [B + X]+ of guanine derivatives occurs mainly through elimination of NH3 and that of trifluoromethyl uracil dissociates primarily through the loss of HF. For tetracyclines, metal ions are bound to ring A at the tricarbonylmethyl group and dissociate initially by the loss of NH3/ND3 from [MH + X]+ and [MD – X]+. The CID spectra of [M + X]+ of tetracyclines are somewhat similar to those of [M + H]+. The dominant fragments from the metal complexes of these compounds are charge remote decompositions involving molecular rearrangements and the loss of small stable molecules. Additionally, tetracyclines and the anti-viral agents show more selectivity towards the Li+ ion than the corresponding complexes with Na+ or K+.

scholarly journals Synthesis, Characterization and Antimicrobial Screening of Novel Hydrazide Ligand & It’s Transition Metal Complexes

2019 ◽  
Vol 31 (4) ◽  
pp. 938-942
Author(s):  
S.P. Bhale ◽  
A.R. Yadav ◽  
S.U. Tekale ◽  
R.B. Nawale ◽  
R.P. Marathe ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Metal Ion ◽  
Octahedral Geometry ◽  
Tetrahedral Geometry ◽  
Metal Acetate ◽  
Spectral Techniques ◽  
Chloride Salts

Different transition metal complexes were synthesized from novel 3-bromo-2-[1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)ethylidene]hydrazide ligand (H2L) and characterized by spectral techniques. The synthesized ligand was found to act mono as well as di deprotonated (OH, NH) manner and stoichiometry of the ligand to metal ions was confirmed to be 1:1 in case of complex using metal chloride salts, whereas 1:2 in case of metal(II) complexes using metal acetate(II) salt. Structures of metal complexes were confirmed by IR, 1H NMR, TGA, XRD, elemental analysis and UV technique which revealed that Mn(II), Co(II), Ni(II), Cu(II) complexes were octahedral geometry and those of Cu(II), Zn(II) showed square planner and tetrahedral geometry around metal ion respectively. Furthermore H2L and its metal complexes were screened for antimicrobial activity which showed that ligand enhanced its biological activity after coordination with metal ions. In particular, Cd(II) and Mn(II) complexes exhibited excellent antifungal activity.

Optisch aktive Übergangsmetall-Komplexe, 97 [1] C5H5Fe(CO)(COMe)-Derivate von Glyphos und Diop / Optically Active Transition Metal Complexes, 97 [1] C5H5Fe(CO)(COMe) Derivatives of Glyphos and Diop

1990 ◽  
Vol 45 (5) ◽  
pp. 579-586 ◽  
Author(s):  
Henri Brunner ◽  
Rudolf Eder
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Column Chromatography ◽  
Optically Active ◽  
Dinuclear Complexes ◽  
Dissociative Mechanism ◽  
Bridging Ligand ◽  
Active Transition ◽  
Derivatives Of

The reaction of CpFe(CO)2Me with (+)-Glyphos and (–)-Diop yields the monosubstitution products 1 and 2, which consist of pairs of diastereomers, differing only in the Fe configuration. With (–)-Diop, additionally dinuclear complexes are formed in which Diop acts as a bridging ligand. The diastereomers can be separated by column chromatography. At higher temperatures the complexes epimerize in solution with respect to the Fe configuration. The formation of free phosphine and CpFe(CO)2Me indicates a dissociative mechanism.

scholarly journals Applications of Coordination Chemistry in Biological Systems

2014 ◽  
Vol 70 (a1) ◽  
pp. C1376-C1376
Author(s):  
Gurpreet Kaur ◽  
Richard Hartshorn
Keyword(s):  
Metal Ions ◽  
Metal Binding ◽  
Binding Sites ◽  
Metal Ion ◽  
Hydrolytic Enzymes ◽  
Dinuclear Complexes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nitrophenyl Phosphate ◽  
Hydrolysis Of

A novel 2,2′:6′,2″-terpyridine–picolylamine-based bridging ligand has been synthesized and fully characterized using a variety of analysis techniques including single crystal X-ray diffraction. As shown in figure (a), the ligand has both tridentate and bidentate metal binding sites available to coordinate with various metal ions. By varying the size of anions both dinuclear complexes and supramolecular assemblies have been produced. Addition of metal salts containing small anions like halides result in formation of Cu2L and Zn2L dinuclear complexes, figure (b), where one metal ion binds at each of the binding sites of the ligand. The metal ions in these complexes mimic active site of the hydrolytic enzymes and promote phosphatediester hydrolysis of model DNA/RNA compounds. Nearly ten times increase in the rate of hydrolysis of bis(p-nitrophenyl)phosphate (BNPP) is observed in comparison to the parent terpyridine and picolylamine complexes under physiological conditions. Larger anions like PF6-, ClO4-, SO42- , NO3- result in formation of Zn4L4 type squares via. head-to-head and tail-to-tail, HH-TT, (H=tridentate site, T=bidentate site) coordination of the ligand. The octahedrally bound Zn(II) ion between two tridentate sites can be replaced with Fe(II) to prepare Fe2Zn2L4 squares. A flat molecule of terephthalic acid was also deliberately encapsulated in the middle of the Fe2Zn2L4 square as shown in figure (c). The head-to-tail, HT, coordination of the ligand in case of Ni(II) results in formation of decanickel wheels, like [Ni10L10Cl4(H2O)6](Cl)15Br·~140H2O shown in figure (d). Due to the large structure of the molecule X-ray crystallographic studies rather have been quite challenging.

Electronic energy transfer in dinuclear metal complexes containing meta-substituted phenylene units

2005 ◽  
Vol 77 (6) ◽  
pp. 1035-1050 ◽  
Author(s):  
A. D’Aléo ◽  
S. Welter ◽  
E. Cecchetto ◽  
L. De Cola
Keyword(s):  
Energy Transfer ◽  
Steady State ◽  
Metal Complexes ◽  
Photophysical Properties ◽  
Electronic Energy ◽  
Dinuclear Complexes ◽  
Time Resolved ◽  
Time Resolved Spectroscopy ◽  
Electronic Energy Transfer ◽  
Dinuclear Metal Complexes

The synthesis and photophysical properties of heterometallic dinuclear complexes based on ruthenium and osmium trisbipyridine units, Ru-mPh3-Os and Ru-mPh5-Os, in which the metal complexes are linked via an oligophenylene bridge centrally connected in the meta position, are described. Electronic energy transfer from the excited ruthenium-based component (donor) to the osmium moiety (acceptor) has been investigated using steady-state and time-resolved spectroscopy. The results obtained for the meta-substituted compounds are compared with the analogous systems in which the phenylene spacers are substituted in the para position. The mechanism of energy transfer is discussed.

Sign in / Sign up

Export Citation Format

Share Document