Chem. Pharm. Bull.(オピニオン)

Thiosemicarbazone complexes of copper(II): structural and biological studies

http://ssu.ac.ir/cms/fileadmin/user_upload/Mtahghighat/tfood/ARTICLES/chemical_safety/Selenium_in_food_and_the_human_body_A_review.pdf

Selenium in food and the human body: A review

Bonding and structure trends of thiosemicarbazone derivatives of metals—An overview

The nature of metal complexes of heterocyclic thiosemicarbazones reported in the literature through 1989 have been reviewed with an emphasis on variations in stoichiometry and stereochemistry. A brief introduction is followed by a survey of the biological activity of the uncomplexed thiosemicarbazones. Next is a section on the chemical nature of thiosemicarbazones including a discussion of preparative methods, modes of coordination and isomerism. This is followed by a discussion of structural information and biological activity of the iron(III), iron(II), copper(II), cobalt(III), cobalt(II) and nickel(II) complexes of heterocyclic thiosemicarbazones. Short sections on the biological activity of other chelating thiosemicarbazones and metal complexes are also included.

Structural and physical correlations in the biological properties of transition metal heterocyclic thiosemicarbazone and S -alkyldithiocarbazate complexes

Physical and spectroscopic studies on novel vanadyl complexes of some substituted thiosemicarbazides.

Mono- and binuclear complexes of malonyl bis(thiosemicarbazide), H4 MBT, with VO2+, Co2+, Ni2+, Cu2+, Cd2+ and Pt4+ have been isolated. The elemental analyses, magnetic moments, spectra [u.v.–vis., i.r., e.s.r. (for Cu2+; VO2+) and mass], thermal and voltammetric measurements [for Co2+ and Ni2+] have been used to characterize the isolated complexes. The ligand behaves as binegative quadridentate with Cu2+, Co2+ and VO2+ ions, binegative pentadentate with Pt4+ and hexadentate, either as trinegative in [Cd2(HMBT)(OC2H5)(C2H5OH)]H2O or mononegative in [Ni2(H3MBT)(OAc)3(C2H5OH)]. The lack of thiol and/or enol hydrogen during the complex formation was confirmed pH-metrically. The pK’s (10.70, 8.50 and 8.15) of H4MBT reveal the removal of CSNH protons in one step and CONH in two steps. Also, the stability constants reveal a higher value for the Cu2+ complex and a lower one for VO2+. The TG analyses suggest high stability for most complexes followed by thermal decomposition in different steps. The kinetic and thermodynamic parameters for some decomposition steps in VO2+and Pt4+ thermograms have been calculated

Spectral, magnetic, electrical and thermal studies on malonyl bis(thiosemicarbazide) complexes

The coordination behaviour of phthaloyl bis(thiosemicarbazide), H4PBT, towards VO2+, Co(II), Ni(II), Cu(II), Zn(II) and ions has been investigated. The elemental analyses, magnetic moments, spectra [UV-Vis, IR, ESR and MS] and thermal studies were used to characterize the isolated complexes. Cyclic voltammetry was used to study the electrochemical behaviour of the Cu(II) complex. The IR spectra showed that the ligand is deprotonated in the complexes and acts as a binegative SSNN donor. The f U–O (mdyn A−1) and the length r U−O (A) of the UO bond are calculated spectroscopically from the IR data. The loss of thiol hydrogen during the formation of complexes was confirmed from the pH-metric titrations of the ligand and its metal(II) complexes. The protonation constants of the ligand (pK1 = 9.45 and pK2 = 7.25) as well as the stability constants of its complexes were calculated. The intensity and position of the V=O band in the IR spectra reflect the geometry of the formed complex. Also, its colour (dark gree...

Spectral, magnetic, thermal and electrochemical studies on phthaloyl bis(thiosemicarbazide) complexes

The chelation behavior of some =N(1) and NH(4) thiosemicarbazones towards copper(II) ions has been investigated The isolated complexes are characterized by elemental analysis, magnetic moment, electronic, IR, ESR and ms spectra, and by thermal and voltammetric measurements The substituents on =N(1) and/or NH(4) thiosemicarbazones and the log K values of the ligands play an important role in complex formation The IR spectra showed that the reagents HAT, HAET, HAPT, HApClPT, H2ST and HBT are deprotonated in the complexes and act as mononegative SN donors; H2SET, H2SpClPT, H2HyMBPT and H2HyMBpClPT, as binegative NSO donors while H2SPT is a mononegative NSO donor The ESR spectra of the complexes are quite similar and exhibit axially symmetric g-tensor parameters with g ‖ > g ⊥ > 20023 The loss of thiol and/or hydroxyl hydrogen was confirmed from potentiometric titrations of the ligands and their copper(II) complexes The protonation constants of the ligands as well as the stability constants of their Cu

Spectral, magnetic, thermal and electrochemical studies on new copper(II) thiosemicarbazone complexes

The preparation and characterization of CuII, CoII, NiII and HgII complexes containing 1,4-diphenylthiosemicarbazide (DPhTSC) of the type [Cu(DPhTSC-H)X.H2O]nH2O (X= Cl, Br or Ac; n=0 or 1) · [M(DPhTSC-H)2yH2O] (M=CoII or NiII; y=0 or 1) and [Hg(DPhTSC)Cl2]2 H2O and [Cu(D-PhTSC)2SO4]H2O are reported. The stereochemistry of the complexes have been studied with the help of magnetic and electronic measurements. The anomalous magnetic moments observed in all cases have been explained. The i.r. spectral studies have been used to determine the bonding sites in the complexes.

Ahmed A. El-Asmy

Papers

Physical and spectroscopic studies on novel vanadyl complexes of some substituted thiosemicarbazides.

Spectral, magnetic, electrical and thermal studies on malonyl bis(thiosemicarbazide) complexes

Spectral, magnetic, thermal and electrochemical studies on phthaloyl bis(thiosemicarbazide) complexes

Spectral, magnetic, thermal and electrochemical studies on new copper(II) thiosemicarbazone complexes

Copper(II), cobalt(II), nickel(II) and mercury(II) complexes of 1,4-diphenylthiosemicarbazide