Abstract
► Electrochemical synthesis of novel bis-thiosemicarbazide metal complexes. ► Spectral studies for the isolated polynuclear thiosemicarbazide materials. ► Kinetic and thermal stability studies for the materials. ► Test the biological activity against some organisms.
Anodic oxidation of Co, Cu, Zn, and Sn metals in an anhydrous acetone solution of 1,1-oxalyl-, malonyl- or succinyl-bis(4-
p-chlorophenylthiosemicarbazide) yields a new polynuclear complexes. The isolated complexes have the general composition [M
2(L)(H
2O)
6], L
=
pClSuTS and M
=
Co(II), Cu(II) or Sn(II), [M
2(L)(H
2O)
n
]·
nH
2O where M
=
Cu(II), Co(II) or Sn(II), L
=
pClOxTS and
n
=
2 or 6, and [M
2(L)(ac)
2]·
nH
2O where M
=
Co(II) or Zn(II), L
=
pClOxTS or pClSuTS and
n
=
2. The thermogravimetry (TG) and derivative thermogravimetry (DTG) have been used to study the thermal decomposition of the investigated bisthiosemicarbazide ligands and their metal complexes. The kinetic thermodynamic parameters such as:
E
∗, Δ
H
∗, Δ
S
∗and Δ
G
∗ are calculated using Horowitz–Metzger (HM) and Coats–Redfern (CR) equations. The kinetic thermodynamic parameters such as:
E
∗, Δ
H
∗, Δ
S
∗and Δ
G
∗ are calculated from the DTG curves. The tested compounds show a reasonable activity against four strains of Gram-negative bacteria;
Escherichia coli,
Pseudomonas aeruginosa species and Gram-positive bacteria
; Bacillus cereus and
Staphylococcus aureus.