?SYNTHESIS, CHARACTERIZATION ANDANTIBACTERIAL ACTIVITY OF SOME TRANSITION METAL COMPLEXES WITH THIOUREA DERIVATIVES

Abstract

Transition metal complexes of Mnf ll), Co(ll) and Ni(II) ions with 2-hydroxyphenylthiourea.
2-carboxyphenylthiourea and 4-methyl-phenylthiourea have been synthesized and characterized on the basis of el-
emental analyses. conductivity and magnetic measurements and from their IR spectral studies. The complexes have
thegeneral formula: Kz[Mz(U-)2 (NO)zl. U = Dinegativedeprotonatedformofthe ligand.2;hydroxyphenylthiourea;
[M(L)zNO,l. where L= 4-methylphenylthiourea and [Mz(L'NNO,)2]' where L-= Urn-negativedeprotonated formof
the ligand.2-carboxyphenylthiourea.with2-hydroxyphenylthioureaand2-carboxyphenylthiourea. MnOI).Co(ll) and
Ni(JI)metal ions form 5-coordinate bridging complexes whereas4-methylphenylthiourea gives rise to 4-coordinated
complexes with the same metal ions. The antibacterial activity of the ligands and their complexes have been tested
with Bacillus subtilis. Somecomplexes show higheractivity thenthat of the free ligand value whereas in some cases
the activity decreases. Some complexes were foundto retainthe same activity as that of the ligand.