ISSN 1070-3632, Russian Journal of General Chemistry, 2018, Vol. 88, No. 2, pp. 305–311. © Pleiades Publishing, Ltd., 2018.
Synthesis and Characterization
of Disulfide-Schiff Base Derivatives and in vitro Investigation
of Their Antibacterial Activity Against Multidrug-Resistant
Acinetobacter baumannii Isolates: A New Study
*, A. Dalmaz
, E. Calıskan
, and G. Dulger
Department of Chemistry, Faculty of Science and Arts, Duzce University, Konuralp, Duzce, 81620 Turkey
Department of Chemistry, Graduate School Natural and Applied Sciences,
Duzce University, Konuralp, Duzce, 81620 Turkey
Department of Medical Microbiology, Faculty of Medicine, Duzce University, Konuralp, Duzce, 81620 Turkey
Department of Medical Biology, Faculty of Medicine, Duzce University, Duzce University, Konuralp, Duzce, 81620 Turkey
Received October 30, 2017
Abstract—In this study two different methods without a catalyst and with a CeO
nano catalyst were used for
the synthesis of dimeric disulfide-Schiff bases. The dimeric disulfide-Schiff base derivatives were
characterized by FT-IR, NMR, and MS spectra, and elemental analysis. The disulfide-Schiff bases and their
derivatives 2–5c were screened for in vitro antibacterial activity against 40 multidrug-resistant strains of
Acinetobacter baumannii, and their minimum inhibitory concentrations were determined. Most of products
exhibited high antibacterial activity against Acinetobacter baumannii.
Keywords: dimeric disulfide-Schiff bases, antibacterial activity, Acinetobacter baumannii, minimum
inhibitory concentration (MIC), nanoceria, multidrug-resistant
The text was submitted by the authors in English.
Metal nanoparticles have attracted considerable
attention in synthetic organic chemistry due to their
high catalytic activity and reusability. However, nano
catalyzed reactions are not common in organic
synthesis . Condensation of 2,2'-diaminodiphenyl
2,2'-disulfide with different aromatic aldehydes gives
rise to a series of interesting Schiff bases of SNNS,
donors, with potential applications in medicine.
Steric and electronic properties of these compounds
can be finely adjusted, thus making them attractive in
coordination and inorganic chemistry [2, 3].
Over recent years, there have been many reports on
applications of Schiff base compounds as antibacterial,
antifungal, anticancer, antioxidant, anti-inflammatory,
antimalarial, and antiviral agents [4, 5].
The Acinetobacter species are gram negative, non-
motile, non-fermentative, opportunistic pathogens that
are widely spread in soil and water and can colonize in
hospitals . Antimicrobial treatment of multidrug-
resistant Acinetobacter baumannii (MDRAB) poses a
significant problem at present time .
RESULTS AND DISCUSSION
In the current study, the title compounds were
synthesized for the first time using a CeO
catalyst, thus adding a new approach to the existing
methods. Synthesis of the dimeric disulfide-Schiff
bases 3–5c was carried out by reacting compound 2
with several aldehydes including 2-hydroxy benzal-
dehyde, 2,3-dihydroxy benzaldehyde, 2,4-dihydroxy
benzaldehyde, 2,5-dihydroxy benzaldehyde, 2-hydroxy-
3-methoxy benzaldehyde, 2-hydroxy-4-methoxy benz-
aldehyde, and 2-hydroxy-5-methoxy benzaldehyde.
Synthesis of these dimeric disulfide-Schiff bases was
carried out in two different ways without catalysts and
nanocatalyst (Schemes 1 and 2). Both
methods were determined to be efficient, however, the
yield of the process catalyzed by CeO