Synthesis, Spectral Characterization and Biological Activity of Metal(II) Complexes of 2,4,5-Trimethoxybenzaldehyde-S-Benzyldithiocarbazone

Abstract

2,4,5-Trimethoxybenzaldehyde was condensed with S-benzyldithiocarbazate to give Schiff base 2,4,5-trimethoxy benzaldehyde-S-benzyldithiocarbazone (BBTC), which was used for complexation with Mn(II), Fe(II) and Co(II) metal ions. The complexes were formulated as M(BBTC)2X2 where X is Cl−, NO3− and CH3COO−. The FTIR spectra of the metal complexes in comparison to that of free ligand suggested the coordination through azomethine nitrogen and thion sulphur forming six membered chelating with metal ion. The magnetic susceptibility and electronic spectral bands revealed octahedral symmetry (Oh) around Mn(II) but tetragonally distorted octahedral symmetry (D4h) of Fe(II) and Co(II) complexes. The positive value of Dt for Fe(II) (68.42-135.2 cm-1) and Co(II) (263-280 cm-1) clearly indicated elongation along z-axis in these complexes which was also supported by the less value of Dq(z) than Dq(xy) for the metal complexes. The ligand as well as its metal complexes have been found active against the bacteria Escherichia coli and Staphylococcus aureus, and antibacterial activity of the free ligand has been observed to have enhanced in metal complexes.

Synthesis, Physicochemical Studies and Powder X‐Ray Diffraction Analyses for New Niclosamide Metal Complexes with Significant Bioactive Behavior

“…The expected computed value of the spin only magnetic moment (μ s.o ) of Co(II) is 3.87 B.M due to Co(II) is a d 7 system with three unpaired electrons, while the actual values of magnetic moment for [Co(NIC)(Cl 2 )(H 2 O) 2 ] complex is 4.72 B.M . The irregular μ eff value may be attributed to 4 T 1g ground state crystal field term in octahedral symmetry which contributes significantly to the magnetic moment of Co(II) complex in octahedral symmetry [26] …”

Recyclable Hypervalent Iodine Reagents in Modern Organic Synthesis

“…8 Several other polymer-supported reagents, such as poly[bis(trifluoroacetoxyiodo)styrene] ( 2 ), polystyrene-supported (hydroxytosyloxyiodo)arenes 3 , and resin-bound alkynyl iodonium salts 4 have also been reported. 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Examples of polymer-supported HVI(III) compounds 1 – 11 are shown in Figure 1 .…”

Synthesis and Physicochemical Studies for Novel Bioactive Metal Complexes of Macrolide Antibiotic Tylosin

“…B.M respectively. The irregular values for Co(II)-TYS complex µ eff may be attributed to 4 T 1g ground state crystal field term in octahedral symmetry which makes a significant contribution to the magnetic moment of Co(II) complex in octahedral symmetry [24]. Typically, Three absorption bands are predicted to occur in the electronic spectra of Co(II) complex with perfect high spin octahedral geometry due to three probable spin allowed transitions, 4 T 1 g(F) → 4 T 2 g(F), 4 T 1 g(F) → 4 T 1 g(P) and 4 T 1 g(F) → 4 A 2 g(F) that represent (ν 1 ), (ν 2 ) and (ν 3 ) respectively, while due to the splitting of 4 T 1g (F), 4 T 2 g and 4 T 1g (P) in their electronic spectra, these cobalt complex of tylosin display four bands in their electronic spectra, as shown in (Figure 3), which are an evidence of axially distorted octahedral symmetry around Co(II) in these metal complexes.…”

“…The electronic spectra of Co(II)-TYS complex reveal four bands, indicating axially distorted octahedral symmetry around Co(II). These bands can be ascribed to the transitions mentioned below under D 4h symmetry [24]: The value of Dq (xy) has been calculated by using the derived equation transition state that is unnoticeable due to the small gap between the two levels which causes absorption energy in the infrared range. From D s and D t values, the value of ν 1 has been estimated and found in 3486 cm −1 , which refers to the infrared spectrum.…”