402
SPASOV et al.
Salts of 9ꢀ(2ꢀdialkylaminoethyl)ꢀ2ꢀ(4ꢀcyanopheꢀ
nyl)imidazo[1,2ꢀ
]benzimidazoles (IV), (V). Benzimiꢀ bind to the 5ꢀНТ2Аꢀreceptors was confirmed by the
dazolium bromide (3.2 mmol) was refluxed in water radioligand analysis [26] using the tritiumꢀlabeled ketꢀ
35 mL for (II)) or aqueous ethanol (60 mL for (III)) anserin with the specific activity of 72 Ci/mmol (Perꢀ
For the most active compounds the capacity to
a
(
until the reaction completion (1.5–3 h). Bromide (II
was completely dissolved, whereas compound (III
was refluxed as a suspension. The solution was cooled,
and the precipitated hydrobromides were filtered off
and dried in air to give 93.3 and 97.5% of (IV) and (V),
respectively. The salts were treated with 22% ammoꢀ
nium hydroxide to pH 8.0, and the bases were
extracted with chloroform. The extract was concenꢀ
trated to a minimal volume and purified by column
chromatography on Al O . The solvent was evaporated
and the bases (IV) and (
tonitrile. Hydrochlorides of (IV) and (
obtained by the treatment of the tricyclic bases in aceꢀ
tone with HClꢀsaturated isopropanol.
)
)
kinꢀElmer).
The study was performed on the membranes isoꢀ
lated from the tissues of cerebral hemisphere frontal
area of Wistar rats. The compounds were studied in the
range of 1 nM to 1 mM. The radioactivity of the samꢀ
ples was measured on a liquid scintillation TriCarb
2
900TR counter (PerkinꢀElmer) with the counting
efficacy of 42–46%. The results were analyzed using
the GraphPad Prism 4 Demo and Statistica 6.0 proꢀ
grams.
2
3
V
) were crystallized from aceꢀ
V
) were
ACKNOWLEDGMENTS
The work was partially supported by the project
section of the state task in the area of scientific activiꢀ
ties, project no. 4.196.2014/K, and was conducted
with the equipment of TsKP Molecular Spectroscopy
of Southern Federal University.
9
ꢀ(2ꢀDiethylaminoethyl)ꢀ2ꢀ(4ꢀcyanophenyl)imiꢀ
dazo[1,2ꢀ ]benzimidazole dihydrochloride (IV 2HCl).
mp 254–255 , cm : 2223 (CN), 1664,
a
⋅
–
1
°
С
. IR,
611 (C=N), 1554–1473 (C=C). Found: C 61.36; H
.91; Cl 16.47; N 16.23%; C H Cl N5. Calc.: C
ν
max
1
5
6
2
2
25
2
1
1.38; H 5.85; Cl 16.50; N 16.27%. H NMR: 11.2 (br
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ꢀ(2ꢀPiperidinoethyl)ꢀ2ꢀ(4ꢀcyanophenyl)imidazoꢀ
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1
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1
2. Šukalovic
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ꢁ
, V., Andric
ꢁ
ꢁ
ꢁ Rajacicꢁ,
ꢁ
RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY Vol. 42
No. 4
2016