Metal uptake by a novel bidentate thiosemicarbazide chelating polymer

Comparative studies between 4-allyl-, 4-phenyl- and 4-ethyl-1-(2-hydroxybenzoyl) thiosemicarbazides and the synthesis, characterization and DFT calculations of binary and ternary complexes derived from 4-ethyl (L(1)) and 2,2'-dipyridyl

The metal complexes of 4-ethyl-1-(2-hydroxybenzoyl) thiosemicarbazide (L(1)) with MCl2 (M=Co(2+), Cu(2+) and Zn(2+)) and Zn(Ac)2 in EtOH were synthesized and characterized using spectral (IR, (1)H-NMR, mass, UV-Visible), magnetic moment and thermal measurements. Binary and ternary complexes with the general formulae, [Cu(L(1)-H)2]·EtOH, [Co(L(1)-H)2], [Zn3(L(1)-H)(L(1))(Ac)5], [Cu2(L(2))2(L(1)-2H)2(H2O)2]·4H2O, [Co(L(2))(L(1)-2H)]·3H2O and [Zn2(L(2))(OH)(L(1)-3H)(H2O)]·1/2EtOH where L(2) is 2,2'-dipyridyl, have been suggested and characterized. The bond lengths, bond angles, chemical reactivates, energy components, binding energies and dipole moments for the isolated complexes were evaluated by DFT method from DMOL(3). Also, the MEP for L(1) is illustrated. The existence of the OH group in the Zn(2+) ternary complexes is confirmed by IR, mass and (1)H-NMR spectra. Biological activity for the L(1) and some its complexes was tested against DNA. Comparative studies between the ligation behavior and reactivity of our previous work derived from 4-phenyl- and 4-allyl-1-(2-hydroxybenzoyl) thiosemicarbazides have been investigated.

Synthesis, spectroscopic studies and inhibitory activity against bacteria and fungi of acyclic and macrocyclic transition metal complexes containing a triamine coumarine Schiff base ligand

Two series of new mono and binuclear complexes with a Schiff base ligand derived from the condensation of 3-acetylcoumarine and diethylenetriamine, in the molar ratio 2:1 have been prepared. The ligand was characterized by elemental analysis, IR, UV-visible, (1)H-NMR and mass spectra. The reaction of the Schiff base ligand with cobalt(II), nickel(II), copper(II), zinc(II) and oxovanadium(IV) lead to mono or binuclear species of cyclic or macrocyclic complexes, depending on the mole ratio of metal to ligand and as well as on the method of preparation. The Schiff base ligand behaves as a cyclic bidentate, tetradendate or pentaentadentae ligand. The formation of macrocyclic complexes depends significantly on the dimension of the internal cavity, the rigidity of the macrocycles, the nature of its donor atoms and on the complexing properties of the anion involved in the coordination. Electronic spectra and magnetic moments of the complexes indicate that the geometries of the metal centers are either square pyramidal or octahedral for acyclic or macro-cyclic complexes. The structures are consistent with the IR, UV-visible, ESR, (1)H-NMR, mass spectra as well as conductivity and magnetic moment measurements. The Schiff base ligand and its metal complexes were tested against two pathogenic bacteria as Gram-positive and Gram-negative bacteria as well as one kind of fungi. Most of the complexes exhibit mild antibacterial and antifungal activities against these organisms.

Synthesis of novel binary and ternary complexes derived from 1-(2-hydroxy benzoyl)-4-phenylthiosemicarbazide (L(1)) and 2,2'-dipyridyl (L(2)) with Co(II), Cu(II) and Zn(II) salts

The complexes derived the reactions of 1-(2-hydroxybenzoyl)-4-phenylthiosemicarbazide (L(1)) with MX2 (M = Co(II), Cu(II) and Zn(II) ions; X = Cl(-) in case of Co(II) and Cu(II) ions, Cl(-) and Ac(-) in case of Zn(II)) in EtOH, were synthesized and characterized. The results suggested that the complexes have the general formulae, [Cu(L(1)-2H)(EtOH)(H2O)2]⋅H2O, [Co(L(1)-2H)(EtOH)(H2O)]⋅2H2O and [Zn(L(1)-2H)(EtOH)]. Also, the ternary complexes, derived from the reactions 2,2'-dipyridyl (L(2)) with the metals salts followed by adding a solution of the L(1) were synthesized and having the general formulae, [Cu2(L(2))(L(1)-2H)(H2O)(OH)2]⋅1/2H2O, [Co(L(2))(L(1)-2H)]⋅1.5EtOH⋅3H2O and [Zn(L(2))(L(1)-2H)]⋅EtOH. The binary and ternary complexes were characterized by elemental analyses, molar conductivities, spectral (IR, UV-Vis, (1)H-NMR and mass), thermal and magnetic measurements. The existence of OH group in the ternary complexes was confirmed by IR spectra. The amounts of solvent were determined from the results of TGA. The biological activity for the ligand and two complexes were tested against DNA.

Comparative spectroscopic and DFT calculations of binary and ternary complexes derived from 4-allyl-1-(2-hydroxybenzoyl) thiosemicarbazide (L¹) and 2,2'-dipyridyl

Five metal complexes derived the reactions of 4-allyl-1-(2-hydroxybenzoyl) thiosemicarbazide (L(1)) with MX2 (M=Co(2+), Cu(2+) and Zn(2+) ions; X=Cl(-) in case of Co(2+) and Cu(2+) ions and Cl(-) and Ac(-) in case of Zn(2+) ion) in EtOH were synthesized and characterized. The results suggested that the binary and ternary complexes have the general formulae, [Cu(L(1)-2H)(EtOH)], [Co(L(1)-2H)(H₂O)₂]⋅H₂O and [Zn(L(1)-2H) (H₂O)1/2]⋅½EtOH, [Cu₂(dipy)(L(1)-2H)(OH)₂(H₂O)], [Co(dipy)(L(1)-2H)]⋅4H₂O and [Zn(dipy)(L(1)-2H)]. The binary and ternary complexes were characterized by elemental analyses, molar conductivities, spectral (IR, UV-vis; (1)H NMR, mass), thermal (TGA, DTG) and magnetic moments measurements. The mode of chelation is suggested using spectral data. The existence of OH group in the ternary complexes is confirmed from the results of IR, mass and (1)H NMR spectra. All the geometries of the ligands and the complexes are confirmed using DFT method from DMOL(3). The biological activity for the L(1) and two metal complexes were tested against DNA.

Synthesis, spectroscopic, coordination and biological activities of some organometallic complexes derived from thio-Schiff base ligands

Two series of mono- and binuclear complexes cyclic or acyclic thio-ferocine Schiff base ligands, derived from the condensation of 2-aminobenzenthiol (L) with monoacetyl ferrocene in the molar ratio 1:1 or in the molar ratio 1:2 for diacetyl ferocine have been prepared. The condensation reactions yield the corresponding Schiff Base ligands, HLa-Maf and H2Lb-Daf. The chelation of the ligands to metal ions occurs through the sulfur of the thiol group as well as the nitrogen atoms of the azomethine group of the ligands. HLa-Maf acts as monobasic bidentate or dibasic tetradentate, while H2Lb-Daf behaves as twice negatively cargend tetradentate ligand. The structures of these ligands were elucidated by elemental analysis, infrared, ultraviolet-visible spectra, as well as (1)H NMR spectra. Reactions of the Schiff bases ligands with ruthenium(III), oxovanadium(IV) and dioxouranium(VI) afforded the corresponding transition metal complexes. The properties of the newly prepared complexes were analyse by elemental analyses, infrared, electronic spectra, (1)H NMR as well as the magnetic susceptibility and conductivity measurement. The metal complexes exhibits different geometrical arrangements such as octahedral and square pyramidal coordination. Schiff base ligands and their metal complexes were tested against two pathogenic bacteria as Gram-positive and Gram-negative bacteria as well as one kind of fungi to study their biological activity. All the complexes exhibit antibacterial and antifungal activities against these organisms.

Synthesis, spectroscopic and biological activities studies of acyclic and macrocyclic mono and binuclear metal complexes containing a hard-soft Schiff base

Mono- and bi-nuclear acyclic and macrocyclic complexes with hard-soft Schiff base, H(2)L, ligand derived from the reaction of 4,6-diacetylresorcinol and thiocabohydrazide, in the molar ratio 1:2 have been prepared. The H(2)L ligand reacts with Co(II), Ni(II), Cu(II), Zn(II), Mn(II) and UO(2)(VI) nitrates, VO(IV) sulfate and Ru(III) chloride to get acyclic binuclear complexes except for VO(IV) and Ru(III) which gave acyclic mono-nuclear complexes. Reaction of the acyclic mono-nuclear VO(IV) and Ru(III) complexes with 4,6-diacetylresorcinol afforded the corresponding macrocyclic mono-nuclear VO(IV) and Ru(IIII) complexes. Template reactions of the 4,6-diacetylresorcinol and thiocarbohydrazide with either VO(IV) or Ru(III) salts afforded the macrocyclic binuclear VO(IV) and Ru(III) complexes. The Schiff base, H(2)L, ligand acts as dibasic with two NSO-tridentate sites and can coordinate with two metal ions to form binuclear complexes after the deprotonation of the hydrogen atoms of the phenolic groups in all the complexes, except in the case of the acyclic mononuclear Ru(III) and VO(IV) complexes, where the Schiff base behaves as neutral tetradentate chelate with N(2)S(2) donor atoms. The ligands and the metal complexes were characterized by elemental analysis, IR, UV-vis (1)H-NMR, thermal gravimetric analysis (TGA) and ESR, as well as the measurements of conductivity and magnetic moments at room temperature. Electronic spectra and magnetic moments of the complexes indicate the geometries of the metal centers are either tetrahedral, square planar or octahedral. Kinetic and thermodynamic parameters were calculated using Coats-Redfern equation, for the different thermal decomposition steps of the complexes. The ligands and the metal complexes were screened for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria, and Pseudomonas fluorescens as Gram-negative bacteria in addition to Fusarium oxysporum fungus. Most of the complexes exhibit mild antibacterial and antifungal activities against these organisms.