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J Incl Phenom Macrocycl Chem (2016) 86:19–25
So, synthetic analogues of such systems are very inter-
(0.003 mol) in 150 cm3 of methanol. After the addition, the
reaction mixture was stirred to room temperature, and
0.006 mol of sodium borohydride in 15 mL of dimethyl
formamide was added in portions with stirring. The yellow
colour of the reaction mixture disappears with addition of
all portion of sodium borohydride, indicated to completion
of hydrogenation. When the reduction was completed,
mixture was poured in cold distilled water. Formed white
precipitate was washed with water and diethyl ether, and
then dried over anhydrous sodium sulphate.
esting, in term of its supramolecular properties, imitating the
properties of naturally occurring systems. The crown ethers
can demonstrate the properties of naturally occurring
membrane active antibiotics, thanks to ionophore feature of
macrocycle cavity to bind the cations trough ion-dipole,
dipole–dipole non-covalent bonds. [3] After the binding, the
ionophore antibiotics, such as valinomycin and nonactin,
drag ions into the bacterial cell, change the permeability of
the membrane and disrupt the oxidative phosphorylation. [4]
Azacrown ethers, cryptands, thiacrown ethers and their
derivatives, having nitrogen, sulphur atoms in macrocyclic
ring, are able to selectively bind to metal ions. The substi-
tution of macrocycle’s oxygen atoms by nitrogen atoms
increases the complex formation ability, as the nitrogen
atoms are softer bases. Azacrown ethers are able to bind the
ions of transfer and rare earth metals. [5] Beside this, the
synthesis of macroheterocycles, having various functional
groups in their molecule, notably influences on the ability of
these compounds to form supramolecular ensembles by
means of non-covalent interactions [6].
Yield of (3) 0.57 g (70 %), m.p. 122–124 °C. Found: C
70.62, H 7.39, N 10.26. Calc. For C16H20O2N2:C 70.59, H
7.35, N 10.29 %. NaOH, dissolved in 0.1 cm3 of water was
added to (3) (0.003 mol) in 150 cm3 of n-butanol
(0.006 mol). The reaction mixture was heated and then
(0.003 mol) of 1,3-dichloro-2-propanol, dissolved in
15 cm3 of n-butanol, was added dropwise during 30 min.
Reaction mixture was stirred and refluxed 30 h. When the
reaction was completed, the mixture was filtered, and then
the filtrate was evaporated to minimum volume. The resi-
due was dissolved in 50 cm3 of water and extracted with
chloroform (3 9 50 cm3). Removal of the solvent gave the
product (4).The further purification was carried by recrys-
tallization from mixture butanol-1:toluene, yield 0.70 g
(65 %), m.p. 148–149 °C. Found: C 69.5, H 7.4, N 8.7.
Calc. for C19H24N2O3: C 69.5, H 7.4, N. 8.5 %. IR (KBr):
3350 (OH); 3330, 1455 (NH); 1604, 1590, 1492 (Ar);
1255, 1035 (Ar–O–CH2); 754 (1,2-Ar) cm-1 .1H NMR (d):
2.64 (s, 4H, NCH2CH2N), 3.24 (br, 3H, NH and OH), 3.65
(s, 4H, ArCH2), 4.14 (m, 5H, CH2CHCH2), 6.74–7.25 (m,
8H, ArH) ppm.
At the same time the potential applications of nanoma-
terial in biomedicine field attract more attention in modern
science. The magnetite nanoparticles have already shown
promising results in preclinical experiments for imaging
contrast enhancement, tissue repair, magnetic hyperthermia
and drug delivery [7–10]. In this regard, the combination of
two perspective approaches in designing new drugs can be
very useful, due to the new advantages, created by unique
features of both nanoparticles and supramolecular com-
pounds. So, the functionalization of magnetite nanoparticle
with hydroxyl substituted diazacrown ether, able to mimic
natural siderophores, is a matter of great scientific and
practical interest.
Synthesis of nanostructures by functionalization
of Fe3O4 with MC (MC@Fe3O4 NPs)
Magnetic iron oxide nanoparticles are usually prepared by
wet chemical precipitation from aqueous iron salt solutions
in alkaline milieu, created by using NH4OH, in the atmo-
sphere of gaseous nitrogen. [11] The formed Fe3O4
nanoparticles (NPs) were separated by strong NdFeB per-
manent magnet, repeatedly washed with distilled water and
dispersed in ethanol. The ethanol solution of MC, taken in
excess, was added to ethanol solution of Fe3O4 nanopar-
ticles and vigorously stirred. After stirring during 8 h at
ambient, the prepared nanostructures were separated by
strong NdFeB permanent magnet and repeatedly were
washed with distilled water. The obtained NPs were dried
at ambient conditions and the iron content in the samples
was analyzed by atom absorption spectroscopy and per-
formed on Varian SpectrAA 220FS Atomic absorption
spectrometer. Samples were prepared by Milestone
ETHOS 1 Microwave extraction unit. The UV spectra have
been recorded on Spectrophotometer specord 250 Plus. UV
Materials and methods
All chemicals, used in the synthesis, were of analytical
grade and used as received. Ethylenediamine, 1,3-dichloro-
2-propanol, salysilaldehyde were purified by distillation
under reduced pressure, created by water pump. FeCl3-
6H2O, FeSO4Á7H2O, NH4OH (25 %), were purchased from
Sigma-Aldrich (Taufkirchen, Germany); Nutrient Broth
was purchased from Biolife (Milano, Italia).
Synthesis of (4) MC 1,13-Diaza-5,9-dioxa-7-hydroxy-
3,4:10,1-dibenzocyclopentadecan
Preparation of MC-general procedure
The ethylenediamine (0.003 mol), dissolved in 20 cm3 of
methanol, was added dropwise to salysilaldehyde (1)
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