Syntheses, spectroscopic, and magnetic properties of polystyrene-anchored coordination compounds of tridentate ONO donor Schiff base

Physicochemical, Spectral, and Biological Studies of Mn(II), Cu(II), Cd(II), Zr(OH)2(IV), and UO2(VI) Compounds with Ligand Containing Thiazolidin-4-one Moiety

The Schiff base (I) upon reacting with mercaptoacetic acid in dry benzene undergoes cyclization and forms N-(2-carbamoylthienyl)-C-(3′-carboxy-2′-hydroxyphenyl)thiazolidin-4-one, LH3(II). A MeOH solution ofIIreacts with Mn(II), Cu(II), Cd(II), Zr(OH)2(IV), and UO2(VI) ions and forms the coordination compounds, [Mn(LH)(MeOH)2], [Cu(LH)]2, [Cd(LH)], [Zr(OH)2(OAc)2(LH3)], and [UO2(NO3)(LH2)(MeOH)]. The compounds have been characterized on the basis of elemental analyses, molar conductance, molecular weight, spectral (IR, reflectance, and EPR) studies and magnetic susceptibility measurements. LH3behaves as a neutral tridentate ONS donor ligand in [Zr(OH)2(OAc)2(LH3)], monobasic tridentate ONS donor ligand in [UO2(NO3)(LH2)(MeOH)], dibasic tridentate OOS donor ligand in [Cu(LH)]2and dibasic tetradentate OONO donor ligand in [Mn(LH)(MeOH)2] and [Cd(LH)]. [Cu(LH)]2is dimer, while all other compounds are monomers in diphenyl. A square-planar structure for [Cu(LH)]2, a tetrahedral structure for [Cd(LH)], an octahedral structure for [Mn(LH)(MeOH)2], a pentagonal-bipyramidal structure for [Zr(OH)2(OAc)2(LH3)], and an eight-coordinate structure for [UO2(NO3)(LH2)(MeOH)] are proposed. The ligand (II) and its compounds show antibacterial activities towardsE. coli. (Gram negative) andS. aureus(Gram positive).

Syntheses, spectral characterization, and antimicrobial studies on the coordination compounds of metal ions with schiff base containing both aliphatic and aromatic hydrazide moieties

An EtOH solution of 3-ketobutanehydrazide and salicylhydrazide on refluxing in equimolar ratio forms the corresponding Schiff base, LH₃ (1). The latter reacts with Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Zr(OH)₂(IV), MoO₂(VI), and UO₂(VI) ions in equimolar ratio and forms the corresponding coordination compounds, [M(LH)(MeOH)₃] (2, M = Mn, Co, Ni), [Cu(LH)]₂ (3), [M′(LH)(MeOH)] (4, M′ = Zn, Cd), [Zr(OH)₂(LH)(MeOH)₂] (5), [MoO₂(LH)(MeOH)] (6), and [UO₂(LH)(MeOH)] (7). The coordination compounds have been characterized on the basis of elemental analyses, molar conductance, spectral (IR, reflectance, ¹H NMR, ESR) studies, and magnetic susceptibility measurements. They are nonelectrolytes in DMSO. The coordination compounds, except 3, are monomers in diphenyl. They are active against gram-positive bacteria (S. aureus, B. subtilis), gram-negative bacteria (E. coli, P. aeruginosa), and yeast (S. cerevisiae, C. albicans). 1 acts as a dibasic tridentate ONO donor ligand in 2–7 coordinating through its both enolic O and azomethine N atoms. The coordination compounds 2 and 3 are paramagnetic, while rest of the compounds are diamagnetic. A square-planar structure to 3, a tetrahedral structure to 4, an octahedral structure to 2, 6, and 7, and a pentagonal bipyramidal structure to 5 are proposed.

Physico-Chemical Studies on the Coordination Compounds of Thiazolidin-4-One

A dry benzene solution of the Schiff base,N-(2-hydroxyphenyl)-3′-carboxy-2′-hydroxybenzylideneimine upon reacting with mercaptoacetic acid undergoes cyclization and formsN-(2-hydroxyphenyl)-C-(3′-carboxy-2′-hydroxyphenyl)thiazolidin-4-one, LH3(I). A MeOH solution ofIreacts with , , , and Mo ions and forms the monomeric coordination compounds, [Mn(LH)(MeOH)3] (II), [Cu(LH)(MeOH)] (III), [Zn(LH)(MeOH)] (IV), [FeCl(LH)(MeOH)2] (V), and [MoO2(LH)(MeOH)](VI). The coordination compounds have been characterized on the basis of elemental analyses, molar conductance, molecular weight, spectral (IR, reflectance, ESR) studies, and magnetic susceptibility measurements.Ibehaves as a dibasic tridentate OOS donor ligand in these compounds. The compounds are nonelectrolytes ( = 6.2–13.8 mho cm2 mol−1) in DMF. A square-planar structure forIII; a tetrahedral structure forIVand an octahedral structure forII,V, andVIare suggested.