Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 2, pp. 285−288.
Pleiades Publishing, Ltd., 2013.
Original Russian Text © G.E. Chikisheva, Yu.E. Sapozhnikov, R.Kh. Mudarisova, L.I. Buslaeva, Z.B. Galieva, D. Davletov, 2013, published in Zhurnal
Prikladnoi Khimii, 2013, Vol. 86, No. 2, pp. 306−309.
Synthesis and Fungicidal Activity
of 2-Benzoylaminobenzimidazole Complex Compounds
G. E. Chikisheva, Yu. E. Sapozhnikov, R. Kh. Mudarisova,
L. I. Buslaeva, Z. B. Galieva, and R. D. Davletov
Scientiﬁ c and Engineering Institute of Herbicides and Plants Growth Regulators,
Academy of Sciences of Bashkortostan Republic, Ufa, Russia
Institute of Organic Chemistry, Ufa Scientiﬁ c Center, Russian Academy of Sciences, Russia
Received November 14, 2012
Abstract—Special features of the formation of 2-benzoylaminobenzimidazole complexes with copper(II) chloride,
sulfate, and acetate were studied. Optimal conditions of obtaining the complexes were found, and chemical com-
positions, some physicochemical properties, and fungicidal activity of the synthesized compounds were studied.
Benzimidazoles belong to a manifold type of chemical
compounds with a biological activity, which is not limited
to antihelminthic activity, but also covers pathogenic
fungi, viruses, and bacteria [1–4]. The methyl ether of
2-benzimidazolylcarbamine acids (BMC) is most known
among 2-aminobenzimidazole derivatives. Earlier [5–7]
various benzoylaminobenzimidazoles were synthesized
and tested for biological activity. The simplest of them,
2-benzoylaminobenzimidazole (2-BABI), is highly com-
petitive with BMC for the fungicidal activity. Benzimid-
azoles readily form complexes with transition metals.
Biological activity and structure of various derivatives of
N-(benzimidazolyl-2)carbamine acid with transition metals
were described in detail in the literature [8–10], however
similar data on the complexes of substituted 2-aminoben-
zimidazoles are practically absent.
In the present work the formation of 2-BABI com-
plexes with copper(II) chloride, sulfate, and acetate in
water-alcohol and water-acetone media was considered,
and their fungicidal activity was determined.
In the experiments we used 2-BABI obtained by
acylating of 2-aminobenzimidazole with benzoyl chloride
in acetone in the presence of triethylamine at 55°С.
Preparation of acyl derivatives of 2-aminobenzimidazole
and also the structure of these compounds studied by
С NMR method were described earlier [5–7].
Chemically-pure grade copper chloride, sulfate, and
acetate were used without additional puriﬁ cation. The
IR spectra of powders in vaseline oil were recorded on
an IR Prestige-21 Fourier-transform infrared Shimadzu
spectrophotometer in the range of 700–3600 cm
and the UV spectra of water-alcohol solutions in the
range of 190-400 nm were taken on a Hitachi M 340
Complex of 2-BABI with copper chloride. 1.185 g
(0.005 mol) of 2-BABI was loaded in a capsule, ﬁ lled in
with a solution of 0.4263 g (0.025 mol) of CuCl
3 ml of H
O, and 1 ml of acetone was added. The result-
ing suspension was heated up with stirring at 55°С within
10 min and dried under an infrared lamp. The obtained
compound was washed free from unreacted copper chlo-
ride by water, then by acetone, and dried above CaCl
The yield of the resulting complex was 87.0% with the
copper content of 10.04 wt %.
Complex of 2-BABI with copper sulfate. 0.6 g
(0.00253 mol) of 2-BABI was dissolved in 50 ml of ac-