ISSN 1070-4272, Russian Journal of Applied Chemistry, 2015, Vol. 88, No. 6, pp. 921−925. © Pleiades Publishing, Ltd., 2015.
INORGANIC SYNTHESIS AND INDUSTRIAL
Synthesis, Characterization, and Antibacterial Activities
of Some Metal Complexes of Heptadentate Schiff Base Ligand
Derived from Acetylacetone
Roya Ranjineh Khojasteh and Sara Jalali Matin
Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran
Received June 3, 2015
Abstract—The preparation and characterization of Fe(III), Ni(II), and Mn(III) complexes of tripodalheptadentate
Schiff-base ligand N[CH
have been studied. Heptadentate Schiff base ligand was
derived from acetylacetone and tris(2-aminoethyl)amine. These compounds have been characterized by elemental
C NMR, IR, and UV–VIS spectroscopy techniques. This is the ﬁ rst study which investi-
gates the antibacterial activity of heptadentate (N
) Schiff base ligand namely tris[(4-hydroxypentenylidene-
2-imino)ethyl]amine and its complexes. The in vitro biological screening effects of the investigated compounds
were tested against the Gram-negative bacteria; Escherichia coli, Pseudomonas aeruginosa and Gram-positive
bacteria; Staphylococcus aureus, Bacillus cereus by the disc diffusion and micro-broth dilution methods. All the
compounds have shown potent antibacterial activity compared to the standards. The metal complexes were shown
to possess more antibacterial activity than the uncomplexed Schiff base.
The increasing number of bacterial and fungal strains
that have developed resistance to classical antibiotics
has intensiﬁ ed the search for new antibiotic compounds.
Heterocyclic compounds have wide applications in ﬁ elds
such as antibacterial, antiviral and have been important in
the advancement of medicinal chemistry [1, 2].
Antipyrine (N-heterocyclic compound) is a marker in
the study of the transfer of drugs in the human body. For
that, the structural features as well as the biological activ-
ity have been studied and a wide range of metal complexes
derived from antipyrine derivatives have been reported
[3–5]. On the other hand, Schiff bases have been play-
ing an important part in the development of coordination
chemistry. The azomethine linkage of the Schiff bases is
responsible for various antibacterial, antifungal activities.
Schiff base ligands can be coordinated to a metal center
from strong donor sites like phenoxo oxygen atoms and
imine nitrogen atoms and form a stable complex [6, 7].
Potential applications of macrocyclic Schiff base as
supramolecular devices are contrast agents in magnetic
resonance imaging (MRI) a nd radiopharmaceuticals. It
can also be used in nanotechnology and as models for bio-
logical systems [8–11]. The complexes with these ligands
and kinetic stability can be regarded as being useful for
applications in diagnostics and medicine. Heptadentate
Schiff base complexes have been synthesized such as:
Cryptate , Cu(II) N
Schiff base , and two In(III)
complexes  of tricarboxylatetraazamacrocycles. The
ﬁ rst two complexes are pentagonal bipyramidal and the
latter two complexes contain tribasic ligands in a trigonal
prismatic geometry capped on a square face. In this study,
) Schiff base ligand derived from
condensation reactions of tris(2-aminoethyl)amine(tren)
with acetylacetone, and their coordination chemistry with
a number of metal ions have been prepared. We also
studied the capability of this ligand and its complexes
The text was submitted by the authors in English.