The synthesis of new amphiphilic p-tert-butylthiacalix[4]arenes containing peptide fragments and their interaction with DNA

Article abstract of DOI:10.1039/c5ob00548e

New water-soluble p-tert-butylthiacalix[4]arenes containing peptide and quaternary ammonium fragments in cone and 1,3-alternate conformations were synthesized and characterized. The interaction of the macrocycles with DNA was studied by UV-spectroscopy, DLS and TEM. It was shown that the interaction of the self-associates based on p-tert-butylthiacalix[4]arenes tetrasubstituted at the lower rim with glycine and quaternary ammonium fragments in cone and 1,3-alternate conformations with DNA led to the formation of particles of about 99-192 nm in size.

Full text of DOI:10.1039/c5ob00548e

Organic &
Biomolecular Chemistry
View Article Online
View Journal
PAPER
The synthesis of new amphiphilic p-tert-
butylthiacalix[4]arenes containing peptide
Cite this: DOI: 10.1039/c5ob00548e
fragments and their interaction with DNA†
Pavel L. Padnya,a Elena A. Andreyko,a Olga A. Mostovaya,a Ildar Kh. Rizvanovb and
Ivan I. Stoikov*a
New water-soluble p-tert-butylthiacalix[4]arenes containing peptide and quaternary ammonium frag-
ments in cone and 1,3-alternate conformations were synthesized and characterized. The interaction of
the macrocycles with DNA was studied by UV-spectroscopy, DLS and TEM. It was shown that the inter-
action of the self-associates based on p-tert-butylthiacalix[4]arenes tetrasubstituted at the lower rim with
glycine and quaternary ammonium fragments in cone and 1,3-alternate conformations with DNA led to
the formation of particles of about 99–192 nm in size.
Received 18th March 2015,
Accepted 15th April 2015
DOI: 10.1039/c5ob00548e
www.rsc.org/obc
Previously, the formation of water-soluble supramolecular
particles based on amphiphilic p-tert-butylthiacalix[4]arenes
Introduction
Synthesis of the supramolecular systems for recognition of containing amide and quaternary ammonium fragments with
biomacromolecules is one of the promising fields of investi- alkyl, aryl, ester and phthalimide groups at the nitrogen atom
gations in supramolecular chemistry and nanotechnology.1–24 in cone conformation was shown and applied for protein recog-
These systems can be applied for the formation of sensors, cat- nition.63 According to the results54–56,63 it can be expected that
alysts, biomimetic systems, selective extractants and drug self-associates based on amphiphilic p-tert-butylthiacalix[4]-
delivery systems.25–32 Synthetic receptors and aggregates based arenes containing the –N+R3 fragment in different confor-
on them can be used as supramolecular systems.6–24,33–37 The mations are able to interact with anionic macromolecules like
molecular platform for the synthesis of this type of receptors DNA. To examine this hypothesis, the amphiphilic p-tert-
should meet certain requirements: first, it should be easily butylthiacalix[4]arenes containing peptide and quaternary
obtained and modified; second, it should recognize biomacro- ammonium fragments in two conformations, i.e. cone and 1,3-
molecules. Calix[4]arene has been one of the most actively alternate, were selected for the synthesis. The introduction of
studied molecular platforms in the last decade.38–51 The ability ammonium groups and peptide fragments in the structure of
of synthetic receptors based on calixarene platform to recog- macrocycles is necessary for the creation of amphiphilic recep-
nize biopolymers is determined by the receptor conformation, tors based on p-tert-butylthiacalix[4]arene and also for the
type of functional groups and the ability of a macrocycle to interaction of the macrocycles with DNA by the formation of
self-assemble. According to the literature, calixarenes that are hydrogen bonds and electrostatic forces. Amide fragments in
able to interact with biomacromolecules contain guanidinium, the structure of macrocycles are necessary to create aggregates
pyridinium, quaternary ammonium substituents,52–56 amino by self-association inspired by the formation of hydrogen
groups,57 amino acid58 and phthalimide fragments.59 It was bonds. The formation of nanoscale aggregates based on p-tert-
also shown that the nanoscale particles based on amphiphilic butylthiacalix[4]arenes will increase the efficiency of the inter-
calixarenes can form stable complexes with DNA.60–62
action of supramolecular systems with DNA by increasing the
number of simultaneous multiple non-covalent interactions
with biomacromolecules. Depending on the conformation of
the calixarene (cone or 1,3-alternate), the formation of different
types of self-associates can be observed. According to the lit-
erature,64 macrocycles in the cone conformation (all four sub-
stituents located at one side of the macrocyclic platform) are
able to form spherical particles – micelles, and in the case of
macrocycles in 1,3-alternate conformation (two substituents
located on each side of the macrocyclic ring) the formation of
aKazan (Volga Region) Federal University, A.M. Butlerov Chemical Institute,
420008 Kremlevskaya, 18, Kazan, Russian Federation. E-mail: Ivan.Stoikov@mail.ru;
Fax: +7-8432-752253; Tel: +7-8432-337463
bA. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre
of the Russian Academy of Sciences, 420088 Kazan, Russian Federation
†Electronic supplementary information (ESI) available. See DOI: 10.1039/
c5ob00548e
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
vesicles occurred. Thus, the influence of the structure and con-
formation of p-tert-butylthiacalix[4]arenes on their interaction
with DNA will also be studied.
In this work, the synthesis of p-tert-butylthiacalix[4]arenes
tetrasubstituted at the lower rim with peptide and quaternary
ammonium groups in cone and 1,3-alternate conformations
and the ability of the macrocycles to interact with DNA in
aqueous solutions are described.
Results and discussion
Synthesis of quaternary ammonium salts based on p-tert-
Scheme 2 (i)
NH2(CH2)2NEt2, CH3OH/C6H5CH3, reflux.
NH2(CH2)3NMe2,
CH3OH/C6H5CH3,
reflux;
(ii)
butylthiacalix[4]arene containing peptide fragments
To synthesize target products, i.e. p-tert-butylthiacalix[4]arenes
containing quaternary ammonium groups, the introduction of
amide fragments in the structure of macrocycles followed by
the interaction of amine groups with the halogenoalkanes was
studied. According to the literature procedure,65 compounds 3
and 4 were synthesized by the reactions of tetraester 1 in cone
conformation with N,N-diethylethane-1,2-diamine and N,N-di-
methylpropane-1,3-diamine (Scheme 1).
Scheme 3 (i) NaHCO3, C6H6/H2O.66
To synthesize p-tert-butylthiacalix[4]arenes containing ter-
tiary amino groups in 1,3-alternate conformation, the
reactions of tetraester 2 with N,N-diethylethane-1,2-diamine
and
N,N-dimethylpropane-1,3-diamine
were
studied
amino acid and L-alanine as the closest chiral analogue of
glycine.
(Scheme 2). The reactions were carried out in toluene-
methanol (1 : 1) under 72 h reflux. Compounds 5 and 6 were
obtained in excellent yields.
The quaternary ammonium salts 14–25 containing amino
acid and peptide fragments were obtained in excellent yields
by the interaction of the p-tert-butylthiacalix[4]arenes 3–6 con-
taining tertiary amino groups with methyl and ethyl fragments
at the nitrogen atom in cone and 1,3-alternate conformations
with alkylating agents 11–13 (Scheme 4). The reactions were
carried out in acetonitrile under 8 h reflux.
To study the complexing properties of p-tert-butylthiacalix-
[4]arenes containing amide, quaternary ammonium and
amino acid fragments, the model salts 26–29 were obtained.
The replacement of bromide anions in quaternary ammonium
salts 14, 17, 20, 23 by nitrate anions is necessary to avoid the
formation of hydrogen bonds between bromide anions and
biomacromolecules. It would significantly complicate the
determination of the interaction between p-tert-butylthiacalix-
[4]arenes and DNA.67,68 The interaction of quaternary
ammonium salts 14, 17, 20, 23 with silver nitrate in aceto-
nitrile at room temperature produced the compounds 26–29
with quantitative yields (Scheme 5). The absence of bromide
anions in the structure of obtained macrocycles was confirmed
by ion chromatography.
To synthesize alkylating reagents necessary to obtain qua-
ternary ammonium salts based on p-tert-butylthiacalix[4]arene,
according to the literature procedure,66 the acylation of glycine
ethyl ester hydrochloride 7, glycylglycine ethyl ester hydro-
chloride 8 and L-alanine ethyl ester hydrochloride 9 with
bromoacetyl bromide 10 was carried out in benzene at room
temperature (Scheme 3). N-Bromoacetyl-glycine ethyl ester 11,
N-bromoacetyl-glycylglycine ethyl ester 12 and N-bromoacetyl-
L-alanine ethyl ester 13 were obtained. The alkylating
reagents 11–13 were chosen because of the presence of amino
acid groups in their structure: glycine as a simple achiral
Thus, water-soluble p-tert-butylthiacalix[4]arenes containing
peptide and quaternary ammonium fragments were syn-
thesized as potential receptors for biomacromolecules. The
structure and composition of the synthesized compounds 5, 6,
1
14–29 were determined by H and 13C NMR, IR spectroscopy,
Scheme 1 (i)
NH2(CH2)3NMe2,
CH3OH/C6H5CH3,
reflux65
;
(ii)
NH2(CH2)2NEt2, CH3OH/C6H5CH3, reflux.65
mass spectrometry and elemental analysis.
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2015

View Article Online
Organic & Biomolecular Chemistry
Paper
cular weight and small size. To determine optimal experi-
mental conditions, electronic spectra of the compounds were
studied. It was found that maximum absorption of DNA and
calix[4]arenes 26–29 coincide at 260 nm. In order to specify
optimal experimental conditions for studying the interaction
of the macrocycles with DNA, the effect of concentration on
the absorption spectra of the substances was studied. Based
on these results, 0.019 mg ml−1 concentration of DNA was
used in the following experiments. The intensity of absorption
of DNA taken at this concentration was about 0.5 and
allowed varying the concentration of the compounds in a wide
range.
It was shown by UV spectroscopy that the interaction
between thiacalix[4]arenes 26–29 and DNA led to a hypochro-
mic effect at 260 nm, however, the shift of maximum of
absorption was not observed. According to the literature,69 the
decrease of the absorption intensity (hypochromic effect)
during the interaction of receptors with DNA can be explained
by changing of the structure of the polynucleotide. It is inter-
esting to note that the rise of baseline in UV spectra was
observed during the interaction of thiacalix[4]arenes 26–29
with DNA. Probably, it can be due to the aggregation of the
DNA with thiacalix[4]arenes. Furthermore, the solutions of bio-
macromolecules were not able to absorb and scatter light
(Rayleigh scattering); hence, they could exert artificially
increased absorption. Fig. 1 shows the absorption spectrum of
DNA, thiacalix[4]arene 29 and their mixture as an example.
The data obtained demonstrate the aggregation of synthetic
macrocycles 26–29 with DNA. According to the results, we
would like to confirm an interaction of a biopolymer with
receptors that leads to the formation of aggregates and to esti-
mate their size by dynamic light scattering (DLS).
Scheme 4 (i) RBr, CH3CN, reflux.
DLS is widely used to study colloidal particles, macromole-
cules and molecular assemblies.70 To confirm the aggregation
of macrocycles with DNA, the size of particles based on thia-
calix[4]arene/DNA was determined, and self-association of
DNA and compounds 26–29 was studied.
It was shown by DLS that in the absence of macrocycles the
particles with a hydrodynamic diameter of about 5 nm were
observed in DNA solution (0.048 mg ml−1). However, the value
of polydispersity was high (PDI ∼ 0.5).
Scheme 5 (i) AgNO3, CH3CN.
The study of complexing properties of p-tert-butylthiacalix[4]-
arenes tetrasubstituted at the lower rim with peptide
fragments toward DNA
The interaction of synthesized thiacalix[4]arenes 26–29 with
the DNA from salmon sperm in 5 mM Tris-HCl buffer was
studied by UV spectroscopy. The DNA from this source was
chosen as a model substrate because of its relatively low mole-
Fig. 1 UV spectra of thiacalix[4]arene 29 (1 × 10−4 M), DNA (0.019 mg
ml−1) and mixture – DNA (0.019 mg ml−1) and thiacalix[4]arene 29
(1 × 10−4 M).
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
Table 1 Size of particles and polydispersity index obtained with macrocycles 26–29 at different concentrations in Tris-HCl buffer (pH 7.5)
Particle size (d, nm); PDI
The concentration of
thiacalix[4]arene
26
27
99.7 (0.21)
104.3 (0.22)
207.4 (0.28)
239.5 (0.40)
896.0 (0.41)
28
75.4 (0.21)
145.5 (0.22)
201.2 (0.23)
244.7 (0.25)
453.7 (0.40)
29
92.8 (0.19)
139.9 (0.20)
425.7 (0.23)
824.5 (0.40)
1004.0 (0.41)
1 × 10−3
M
141.6 (0.13)
161.6 (0.18)
208.9 (0.26)
389.5 (0.37)
488.7 (0.40)
8 × 10−4 M
1 × 10−4 M
1 × 10−5
M
1 × 10−6 M
Fig. 3 TEM images of self-associates based on thiacalix[4]arene 28 at
10−5 M concentration.
amino acid fragments in cone conformation were also investi-
gated by transmission electron microscopy (TEM). The exist-
ence of spherical nanoparticles with the sizes very close to
those determined by DLS (Table 1) was confirmed (Fig. 3).
The interaction of macrocycles 26, 28 and 27, 29 in cone
and 1,3-alternate conformations with DNA was studied. In the
case of aggregates based on DNA and macrocycles 26, 28 in
cone conformation, the increase of the size of associates was
observed for decreasing thiacalix[4]arene concentration. Then,
the formation of aggregates with a minimum size of about
191.6 nm and 166.6 nm, respectively, occurred at 10−5 M con-
centration. The polydispersity index of these systems changed
in the same direction. In the case of associates based on DNA
and the thiacalix[4]arenes 27, 29 in 1,3-alternate conformation,
the size of aggregates and polydispersity index decreased with
the concentration of thiacalix[4]arenes. The minimum size of
aggregates was also observed at 10−5 M concentration (98.7 nm
and 131.0 nm, respectively) (Table 2).
Fig. 2 Possible paths for the formation of supramolecular associates.
The solutions of thiacalix[4]arenes 26, 28 (cone) and 27, 29
(1,3-alternate) at different concentrations (10−3–10−6 M) were
studied. The consistent increase in the size of aggregates
corresponded to the decrease in the concentration observed
for macrocycles 26–29 with no respect for the macrocycle con-
formation. The value of polydispersity was increased simul-
taneously (Table 1). It can be assumed that the increasing size
of aggregates with decreasing thiacalix[4]arene concentration
can be explained by changing the shape of self-associates
(Fig. 2). As a rule, spherical aggregates (Fig. 2(A and A′))
should be smaller than the elongated self-associates (Fig. 2(B,
B′ and C)).35
It was shown that DNA can interact with macrocycles54–56
and self-associates based on them.60–62 It can be assumed that
in the case of formation of aggregates based on a macrocycle
and DNA with sizes larger than the size of self-associates
The nanoscale aggregates formed by the p-tert-butylthia-
calix[4]arene 28 containing amide, quaternary ammonium and
Table 2 Size of particles and polydispersity index obtained with macrocycles 26–29 and DNA (0.048 mg ml−1) in Tris-HCl buffer (pH 7.5)
Particle size (d, nm); PDI
The concentration of
thiacalix[4]arene
DNA and 26
DNA and 27
DNA and 28
DNA and 29
8 × 10−4 M
1 × 10−4 M
1 × 10−5 M
528.2 (0.30)
926.7 (0.74)
191.6 (0.21)
700.5 (0.25)
630.5 (0.21)
98.7 (0.11)
295.5 (0.50)
757.7 (0.70)
166.6 (0.09)
695.3 (0.33)
559.3 (0.27)
131.0 (0.16)
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2015

View Article Online
Organic & Biomolecular Chemistry
Paper
thiacalix[4]arenes 26–29. The existence of spherical self-associ-
ates based on macrocycle 28 and spherical aggregates formed
by thiacalix[4]arene 28 with DNA was confirmed by TEM.
Conclusions
Thus, water-soluble p-tert-butylthiacalix[4]arenes tetrasubsti-
tuted at the lower rim with amide and quaternary ammonium
groups with peptide fragments in cone and 1,3-alternate con-
formation were synthesized. Thiacalix[4]arenes as complexing
agents toward salmon sperm DNA were studied by UV spectro-
scopy, dynamic light scattering and transmission electron
microscopy. It was determined that water-soluble p-tert-
butylthiacalix[4]arenes tetrasubstituted at the lower rim in the
cone and 1,3-alternate conformations are able to form associ-
ates with hydrodynamic diameters of about 75–142 nm at
10−3 M concentrations in aqueous solution. It was shown that
the interaction of water-soluble thiacalix[4]arenes (10−5 M)
with salmon sperm DNA (0.048 mg ml−1) leads to the for-
mation of monodisperse nanoparticles with polydispersity
index equal to 0.09–0.21 and hydrodynamic diameter of about
99–192 nm. These results open new opportunities to obtain
innovative sensors and drug delivery systems.
Fig. 4 Possible paths for the formation of aggregates based on amphi-
philic calixarenes 26, 28 and 27, 29 and DNA.
Experimental
General
The 1H and 13C NMR spectra of compounds (3–5% solution in
CDCl3, (CD3)2SO) were recorded on 400 MHz and 100 MHz
Bruker Avance 400 spectrometer using CDCl3 and (CD3)2SO as
the internal standard.
Fig. 5 TEM images of aggregates based on macrocycle 28 (10−5 M) and
DNA (0.048 mg ml−1).
The IR spectra were recorded on Spectrum 400 (Perkin
Elmer) IR spectrometer. The IR spectra from 4000 to 400 cm−1
were considered in this analysis. The spectra were measured
with 4 cm−1 resolution and 14 scans co-addition.
Elemental analysis was performed on Perkin–Elmer 2400
Series II instruments.
based on macrocycles 26, 28 and 27, 29, the interaction of self-
associates with DNA took place (Fig. 4(A and A′)). However, the
size of aggregates based on a macrocycle and DNA becomes
smaller than the size of self-associates based on thiacalix[4]-
arenes 26, 28 and 27, 29 at 10−5 M concentration of the recep-
tors. In this case, it can be assumed that DNA interacts with
single molecules of thiacalix[4]arenes instead of their self-
associates (Fig. 4(B and B ′)).
The shape and the size of self-associates based on the
macrocycle 28 and DNA with a hydrodynamic diameter of
about 166.6 nm determined by DLS were also investigated by
TEM. Fig. 5 shows TEM images of the spherical nanoparticles
formed by the thiacalix[4]arene 28 with DNA. According to the
TEM, the size of the aggregates is comparable with the hydro-
dynamic diameter measured by DLS (Table 2).
Mass spectra (MALDI-TOF) were recorded on an Ultraflex III
mass spectrometer in the 4-nitroaniline matrix.
Mass spectra (ESI) were recorded on an AmaZonX mass
spectrometer (Bruker Daltonik GmbH, Germany). The drying
gas was nitrogen at 300° C. The capillary voltage was 4.5 kV.
The samples were dissolved in acetonitrile (concentration
∼10−6 g ml−1).
Melting points were determined using Boetius Block appar-
atus. The purity of the compounds was monitored by melting
and boiling points, and 1H NMR and thin layer chromato-
graphy (TLC) on 200 μm UV 254 silica gel plate using UV-light
(254 nm).
To determine the presence of anions in the aqueous solu-
tions of thiacalixarene, ion chromatography ICS-5000 DIONEX
was performed.
In this work, the following reagents and solvents were used:
acetonitrile (chemical pure), benzene (chemical pure), bromo-
Thus, it was determined by UV spectroscopy that thiacalix-
[4]arenes tetrasubstituted at the lower rim with peptide frag-
ments are able to effectively interact with DNA. It was shown
by DLS that most monodisperse systems based on thiacalix[4]-
arenes and DNA with a small diameter of the aggregates (less
than 200 nm) are able to form at a 10−5 M concentration of
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
acetyl bromide (chemical pure), distilled water, sodium hydro- 1661 (CvO), 2964, 3322 (NH); MALDI-TOF: calcd for [M + H]+
gen carbonate (chemical pure), N,N-dimethylpropane-1,3- m/z = 1344.9, found m/z = 1344.0; El. Anal. Calcd for
diamine (chemical pure), N,N-diethylethane-1,2-diamine C72H112N8O8S4: C, 64.25; H, 8.39; N, 8.33; S, 9.53. Found: C,
(chemical pure), methanol (chemical pure), silver nitrate 64.65; H, 8.12; N, 7.88; S 9.05.
(chemical pure), toluene (chemical pure), glycine ethyl ester
hydrochloride (chemical pure), glycylglycine ethyl ester hydro-
chloride (chemical pure), L-alanine ethyl ester hydrochloride
General procedure for the synthesis of the compounds 14–25
(chemical pure), salmon sperm DNA (Fluka Biochemika; In a round bottom flask equipped with a magnetic stirrer and
protein content <5%, molecular weight 384 000), Tris-HCl a reflux condenser, the compounds 3–6 (0.20 g, 0.15 × 10−3
(Sigma).
mol) were dissolved in 10 ml acetonitrile. N-Bromoacetyl-
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(ethoxycarbonyl)- glycine ethyl ester 11 66, N-bromoacetyl-glycylglycine ethyl ester
methoxy]-2,8,14,20-tetrathiacalix[4]arenes (cone-1 and 1,3- 12 66 and N-bromoacetyl-L-alanine ethyl ester 13 66 (0.62 × 10−3
alternate-2) were synthesized according to the literature mol) were added. The reaction mixture was refluxed for 8 h.
procedure.71
The solvent was removed under reduced pressure. The precipi-
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-di- tate was washed with water and dried under reduced pressure
methyl)aminopropyl)carbamoylmethoxy]-2,8,14,20-tetrathia- over phosphorus pentoxide.
calix[4]arene (cone-3) was synthesized according to the
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
3′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammonium-
literature procedure.65
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-di- propyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene tetra-
ethyl)aminoethyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]- bromide (cone-14). White powder, yield: 0.34 g (95%). Mp:
arene (cone-4) was synthesized according to the literature 114 °C; 1H NMR (400 MHz, 298 K, CDCl3) δ 1.12 (s, 36H,
3
procedure.65
(CH3)3C), 1.27 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 2.32 (m, 8H,
NHCH2CH2CH2N+), 3.51 (s, 24H, (CH3)2N+), 3.55 (m, 8H,
NHCH2CH2CH2N+), 4.01 (m, 8H, NHCH2CH2CH2N+), 4.02 (d,
General procedure for the synthesis of the compounds 5 and 6
In a round bottom flask equipped with a magnetic stirrer and 3JHH = 5.8 Hz, 8H, NHCH2CO), 4.16 (q, JHH = 7.1 Hz, 8H,
a reflux condenser, the compound 271 (0.50 g, 0.46 × 10−3 mol) CH3CH2O–), 4.70 (s, 8H, N+CH2CO), 5.03 (s, 8H, OCH2CO),
in 30 ml of a mixture of toluene and methanol (1 : 1) was dis- 7.36 (s, 8H, ArH), 8.68 (br.s, 4H, NHCH2CH2CH2N+), 9.28 (t,
3
solved. N,N-dimethylpropane-1,3-diamine or N,N-diethyl- 4H, JHH = 5.8 Hz, NHCH2CO); 13C NMR (100 MHz, CDCl3)
3
ethane-1,2-diamine (1.00 ml) was added. The reaction mixture δ 169.11, 168.94, 163.71, 157.80, 147.70, 134.91, 128.13, 74.43,
was refluxed for 72 h. The solvent was removed under reduced 65.32, 63.20, 61.47, 51.85, 41.23, 36.19, 34.31, 31.08, 23.17,
pressure. The precipitate was washed with water and dried 14.16; IRνmax 1199 (COC), 1675 (CvO), 2960, 3331 (N–H); ESI:
under reduced pressure over phosphorus pentoxide.
calcd for [M − 2 Br−]2+ m/z = 1012.9, [M − 3 Br−]3+ m/z = 648.7,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-di- [M − 4 Br−]4+ m/z = 466.6, found m/z = 1012.9, 649.0, 466.5; El.
methyl)aminopropyl)carbamoylmethoxy]-2,8,14,20-tetrathia- Anal. Calcd for C92H144Br4N12O20S4: C, 50.55; H, 6.64; N, 7.69;
calix[4]arene (1,3-alternate-5). White powder, yield: 0.57 g S, 5.87. Found: C, 50.11; H, 6.90; N, 7.38; S, 6.00.
1
(95%). Mp: 81 °C; H NMR (400 MHz, 298 K, CDCl3) δ 1.24 (s,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
36H, (CH3)3C), 1.76 (m, 8H, –NCH2CH2CH2NH), 2.23 (s, 24H, 3′-{([ethoxycarbonylmethyl]amidocarbonylmethyl)amidocarbo-
(CH3)2N), 2.37 (m, 8H, –NCH2CH2CH2NH), 3.37 (m, 8H, nylmethyl})ammoniumpropyl)carbamoylmethoxy]-2,8,14,20-
NCH2CH2CH2NH), 4.05 (s, 8H, OCH2CO), 7.57 (s, 8H, ArH), tetrathiacalix[4]arene tetrabromide (cone-15). White powder,
8.29 (br.s, 4H, CONH); 13C NMR (100 MHz, CDCl3) δ 168.23, yield: 0.34 g (94%). Mp: 113 °C; 1H NMR (400 MHz, 298 K,
3
157.07, 147.18, 133.59, 127.26, 71.42, 57.64, 45.37, 38.13, DMSO-d6) δ 1.08 (s, 36H, (CH3)3C), 1.19 (t, JHH = 7.1 Hz, 12H,
34.25, 31.12, 27.18; IRνmax 1649 (CvO), 2952, 3312 (NH); CH3CH2O–), 1.97 (m, 8H, NHCH2CH2CH2N+), 3.21 (s, 24H,
MALDI-TOF: calcd for [M + H]+ m/z = 1290.9, [M + Na]+ m/z = (CH3)2N+), 3.25 (m, 8H, NHCH2CH2CH2N+), 3.55 (m, 8H,
3
1312.9, [M + K]+ m/z = 1328.9, found m/z = 1290.2, 1312.2, NHCH2CH2CH2N+), 3.85 (d, JHH = 5.5 Hz, 8H, NHCH2CO),
3
3
1328.2; El. Anal. Calcd for C68H104N8O8S4: C, 63.32; H, 8.13; N, 3.87 (d, JHH = 5.3 Hz, 8H, NHCH2CO), 4.09 (q, JHH = 7.1 Hz,
8.69; S, 9.94. Found: C, 63.02; H, 8.72; N, 8.73; S, 9.51.
8H, CH3CH2O–), 4.15 (s, 8H, N+CH2CO), 4.84 (s, 8H, OCH2CO),
3
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-di- 7.40 (s, 8H, ArH), 8.50 (t, JHH = 5.5 Hz, 4H, CONH), 8.54 (t,
ethyl)aminoethyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]- 3JHH = 5.9 Hz, 4H, NHCH2CH2CH2N+), 8.89 (t, JHH = 5.3 Hz,
3
arene (1,3-alternate-6). White powder, yield: 0.54 g (89%). Mp: 4H, CONH); 13C NMR (100 MHz, DMSO-d6) δ 169.63, 168.38,
3
181 °C; 1H NMR (400 MHz, 298 K, CDCl3) δ 1.03 (t, JHH
=
=
168.24, 163.14, 158.03, 146.58, 134.27, 128.00, 74.37, 62.93,
62.11, 60.47, 51.16, 41.59, 40.59, 35.40, 33.90, 30.69, 22.76,
= 6.8 Hz, 8H, 14.03; IRνmax 1197 (COC), 1667 (CvO), 2964, 3056 (N–H); ESI:
3
7.1 Hz, 24H, (CH3CH2–), 1.24 (s, 36H, (CH3)3C), 2.57 (q, JHH
3
7.1 Hz, 16H, –CH2CH3), 2.65 (t, JHH
–NCH2CH2NH), 3.39 (m, 8H, NCH2CH2NH), 4.06 (s, 8H, calcd for [M − 4 Br−]4+ m/z = 523.7, found m/z = 523.8; El. Anal.
OCH2CO), 7.57 (s, 8H, ArH), 8.06 (t, 3JHH = 5.3 Hz, 4H, CONH); Calcd for C100H156Br4N16O24S4: C, 49.75; H, 6.51; Br, 13.24; N,
13C NMR (100 MHz, CDCl3) δ 168.34, 156.96, 147.10, 133.61, 9.28; S, 5.31. Found: C, 48.62; H, 6.04; Br, 12.05; N, 7.19; S,
127.36, 71.19, 51.56, 47.17, 37.27, 34.23, 31.15, 11.91; IRνmax 3.55.
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2015

View Article Online
Organic & Biomolecular Chemistry
Paper
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl- 7.47; IRνmax 1196 (COC), 1668 (CvO), 2960, 3212 (N–H); ESI:
3′-{(ethoxycarbonyl[S-methyl]methyl)amidocarbonylmethyl})- calcd for [M − 3 Br−]3+ m/z = 743.6, [M − 4 Br−]4+ m/z = 537.7,
ammoniumpropyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix- found m/z
[4]arene tetrabromide (cone-16). White powder, yield: 0.32 g 104H164Br4N16O24S4: C, 50.56; H, 6.69; Br, 12.94; N, 9.07; S,
(95%). Mp: 116 °C; 1H NMR (400 MHz, 298 K, CDCl3) δ 1.07 (s, 5.19. Found: C, 50.52; H, 6.51; Br, 12.92; N, 8.79; S, 4.78.
=
743.7, 537.7; El. Anal. Calcd for
C
36H, (CH3)3C), 1.18 (t, 3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.31 (d,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl-
3JHH = 7.3 Hz, 12H, CH3CH), 1.97 (m, 8H, NHCH2CH2CH2N+), 2′-{(ethoxycarbonyl[S-methyl]methyl)amidocarbonylmethyl})-
3.19 (s, 24H, (CH3)2N+), 3.25 (m, 8H, NHCH2CH2CH2N+), 3.56 ammoniumethyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]-
3
(m, 8H, NHCH2CH2CH2N+), 4.09 (q, JHH = 7.1 Hz, 8H, arene tetrabromide (cone-19). White powder, yield: 0.32 g
CH3CH2O–), 4.16 (s, 8H, N+CH2CO), 4.27 (m, 4H, CH3CH), 4.82 (95%). Mp: 116 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.08
3
(s, 8H, OCH2CO), 7.39 (s, 8H, ArH), 8.53 (t, JHH = 5.4 Hz, 4H, (s, 36H, (CH3)3C), 1.18 (t, 3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.30
3
3
3
NHCH2CH2CH2N+), 9.03 (d, JHH = 6.6 Hz, 4H, CONH); 13C (d, JHH = 7.3 Hz, 12H, CH3CH), 1.31 (t, JHH = 7.2 Hz, 24H,
NMR (100 MHz, DMSO-d6) δ 171.72, 168.27, 168.13, 162.96, CH3CH2N+), 3.48–3.61 (m, 24H, NHCH2CH2N+, N+CH2CH3),
157.91, 146.66, 134.39, 128.11, 128.04, 74.21, 62.80, 61.71, 3.67 (m, 8H, NHCH2CH2N+), 4.09 (s, 8H, N+CH2CO), 4.11 (m,
60.80, 51.18, 47.97, 35.36, 33.90, 30.69, 22.64, 16.53, 14.00; 8H, CH3CH2O–), 4.26 (m, 4H, CH3CH), 4.87 (s, 8H, OCH2CO),
IRνmax 1157 (COC), 1676 (CvO), 2961, 3330 (N–H); ESI: calcd 7.40 (s, 8H, ArH), 8.81 (br.s, 4H, NHCH2CH2N+), 9.23 (br.s, 4H,
for [M − 4 Br−]4+ m/z = 480.6, found m/z = 480.5; El. Anal. CONH); 13C NMR (100 MHz, DMSO-d6) δ 171.71, 169.17,
Calcd for C96H152Br4N12O20S4: C, 51.42; H, 6.83; Br, 14.25; N, 162.88, 157.56, 146.56, 134.64, 127.81, 73.96, 60.62, 56.43,
7.50; S, 5.72. Found: C, 51.62; H, 6.74; Br, 14.82; N, 7.33; S, 56.23, 55.32, 47.98, 33.81, 32.34, 30.66, 16.47, 13.98, 7.39;
5.96.
IRνmax 1157 (COC), 1676 (CvO), 2964, 3316 (N–H); ESI: calcd
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl- for [M − 2 Br−]2+ m/z = 1069.5, [M − 3 Br−]3+ m/z = 686.3,
2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammoniu- [M − 4 Br−]4+ m/z = 494.6, found m/z = 1069.1, 685.9, 494.7; El.
methyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene Anal. Calcd for C100H160Br4N12O20S4: C, 52.26; H, 7.02; N, 7.31;
tetrabromide (cone-17). White powder, yield: 0.34 g (95%). S, 5.58. Found: C, 52.52; H, 6.96; N, 7.22; S, 5.43.
1
Mp: 111 °C; H NMR (400 MHz, 298 K, CDCl3) δ 1.12 (s, 36H,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
3
3
(CH3)3C), 1.27 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 1.53 (t, JHH 3′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammonium-
= 7.0 Hz, 24H, CH3CH2N+), 3.74 (m, 8H, NHCH2CH2N+), 3.88 propyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene
(m, 8H, NHCH2CH2N+), 3.96 (d, 3JHH = 5.7 Hz, 8H, NHCH2CO), tetrabromide (1,3-alternate-20). White powder, yield: 0.34 g
4.03 (q, JHH = 7.0 Hz, 16H, CH3CH2N+), 4.16 (q, JHH = 7.1 Hz, (93%). Mp: 112 °C; 1H NMR (400 MHz, 298 K, CDCl3) δ 1.18 (t,
3
3
8H, CH3CH2O–), 4.66 (s, 8H, N+CH2CO), 4.98 (s, 8H, OCH2CO), 3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.20 (s, 36H, (CH3)3C), 1.93
7.35 (s, 8H, ArH), 8.94 (t, JHH = 5.7 Hz, 4H, NHCH2CH2N+), (m, 8H, NHCH2CH2CH2N+), 3.18 (m, 8H, NHCH2CH2CH2N+),
3
9.51 (t, JHH = 5.7 Hz, 4H, NHCH2CO); 13C NMR (100 MHz, 3.21 (s, 24H, (CH3)2N+), 3.52 (m, 8H, NHCH2CH2CH2N+), 3.94
3
3
CDCl3) δ 169.87, 168.78, 163.60, 157.30, 147.73, 134.98, 128.24, (d, JHH = 5.8 Hz, 8H, NHCH2CO), 3.99 (s, 8H, OCH2CO), 4.10
74.14, 61.39, 57.50, 57.03, 56.44, 41.12, 34.26, 33.69, 31.09, (q, JHH = 7.1 Hz, 8H, CH3CH2O–), 4.16 (s, 8H, N+CH2CO), 7.60
3
14.17, 8.48; IRνmax 1198 (COC), 1676 (CvO), 2962, 3314 (N–H); (s, 8H, ArH), 8.04 (br.s, 4H, NHCH2CH2CH2N+), 9.08 (t, JHH
=
3
ESI: calcd for [M − 2 Br−]2+ m/z = 1041.2, [M − 3 Br−]3+ m/z = 5.8 Hz, 4H, NHCH2CO); 13C NMR (100 MHz, CDCl3) δ 168.96,
667.5, [M − 4 Br−]4+ m/z = 480.6, found m/z = 1041.5, 667.6, 163.15, 155.94, 147.57, 130.02, 128.24, 69.59, 64.45, 63.42,
480.6; El. Anal. Calcd for C96H152Br4N12O20S4: C, 51.42; H, 61.54, 52.62, 41.10, 36.94, 34.42, 31.52, 29.70, 23.32, 14.16;
6.83; Br, 14.25; N, 7.50; S, 5.72. Found: C, 51.17; H, 6.70; Br, IRνmax 1677 (CvO), 2959, 3202 (N–H); ESI: calcd for [M − 2
13.90; N, 7.68; S, 5.86.
Br−]2+ m/z = 1012.9, [M − 3 Br−]3+ m/z = 648.7, [M − 4 Br−]4+
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl- m/z = 466.6, found m/z = 1013.0, 649.0, 466.6; El. Anal. Calcd
2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl)amidocarb- for C92H144Br4N12O20S4: C, 50.55; H, 6.64; Br, 14.62; N, 7.69; S,
onylmethyl})ammoniumethyl)carbamoylmethoxy]-2,8,14,20- 5.87. Found: C, 50.90; H, 6.27; Br, 14.57; N, 7.12; S, 5.94.
tetrathiacalix[4]arene tetrabromide (cone-18). White powder,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
yield: 0.35 g (94%). Mp: 120 °C; 1H NMR (400 MHz, 298 K, 3′-{([ethoxycarbonylmethyl]amidocarbonylmethyl)amidocarbo-
3
DMSO-d6) δ 1.08 (s, 36H, (CH3)3C), 1.19 (t, JHH = 7.1 Hz, 12H, nylmethyl})ammoniumpropyl)carbamoylmethoxy]-2,8,14,20-
3
CH3CH2O–), 1.28 (t, JHH = 6.9 Hz, 24H, CH3CH2N+), 3.50–3.58 tetrathiacalix[4]arene tetrabromide (1,3-alternate-21). White
(m, 24H, CH3CH2N+, NHCH2CH2N+), 3.66 (m, 8H, powder, yield: 0.35 g (93%). Mp: 120 °C; H NMR (400 MHz,
1
NHCH2CH2N+), 3.84 (d, 3JHH = 5.7 Hz, 8H, NHCH2CO), 3.87 (d, 298 K, DMSO-d6) δ 1.18 (t, JHH = 7.1 Hz, 12H, CH3CH2O–),
3
3
3JHH = 5.9 Hz, 8H, NHCH2CO), 4.09 (q, JHH = 7.1 Hz, 8H, 1.19 (s, 36H, (CH3)3C), 1.97 (m, 8H, NHCH2CH2CH2N+), 3.13
CH3CH2O–), 4.14 (s, 8H, N+CH2CO), 4.86 (s, 8H, OCH2CO), (m, 8H, NHCH2CH2CH2N+), 3.20 (s, 24H, (CH3)2N+), 3.52 (m,
3
7.40 (s, 8H, ArH), 8.50 (t, JHH = 5.7 Hz, 4H, NHCH2CH2N+), 8H, NHCH2CH2CH2N+), 3.84 (br.s, 8H, NHCH2CO), 3.86 (br.s,
3
3
8.50 (br.s, 4H, NHCH2CO), 8.94 (t, JHH = 5.7 Hz, 4H, 8H, NHCH2CO), 3.96 (s, 8H, OCH2CO), 4.08 (q, JHH = 7.1 Hz,
NHCH2CO); 13C NMR (100 MHz, DMSO-d6) δ 169.44, 168.25, 8H, CH3CH2O–), 4.12 (s, 8H, N+CH2CO), 7.59 (s, 8H, ArH), 8.04
168.12, 163.01, 157.64, 146.56, 134.51, 128.03, 71.07, 60.52, (br.s, 4H, NHCH2CH2CH2N+), 8.52 (t, JHH = 5.8 Hz, 4H,
3
56.60, 55.98, 55.14, 41.50, 40.56, 33.77, 31.98, 30.55, 14.04, CONH), 8.90 (br.s, 4H, CONH); 13C NMR (100 MHz, DMSO-d6)
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
δ 169.56, 168.33, 168.19, 163.31, 156.77, 146.77, 133.06, CH3CH2O–), 4.13 (s, 8H, N+CH2CO), 7.60 (s, 8H, ArH), 8.23 (br.
127.50, 70.81, 62.61, 62.05, 60.47, 51.21, 41.56, 40.49, 35.80, s, 4H, NHCH2CH2), 8.51 (t, 3JHH = 6.0 Hz, 4H, CONH), 8.93 (br.
33.81, 30.75, 22.60, 14.04; IRνmax 1197 (COC), 1667 (CvO), s, 4H, CONH); 13C NMR (100 MHz, DMSO-d6) δ 169.70, 168.48,
2962, 3214 (N–H); ESI: calcd for [M − 3 Br−]3+ m/z = 724.8, [M 168.36, 163.28, 157.84, 147.44, 131.21, 127.54, 72.31, 61.69,
− 4 Br−]4+ m/z = 523.7, found m/z = 724.7, 523.7; El. Anal. 59.65, 55.87, 55.05, 41.49, 40.56, 33.89, 32.44, 30.85, 14.00,
Calcd for C100H156Br4N16O24S4: C, 49.75; H, 6.51; Br, 13.24; N, 7.40; IRνmax 1197 (COC), 1666 (CvO), 2964, 3216 (N–H); ESI:
9.28; S, 5.31. Found: C, 49.94; H, 6.21; Br, 13.16; N, 9.14; S, calcd for [M − 3 Br−]3+ m/z = 743.6, [M − 4 Br−]4+ m/z = 537.7,
5.63.
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
3′-{(ethoxycarbonyl[S-methyl]methyl)amidocarbonylmethyl})- 5.19. Found: C, 50.35; H, 6.35; Br, 12.50; N, 7.10; S, 4.81.
ammoniumpropyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]- 5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl-
found m/z
=
743.6, 537.5; El. Anal. Calcd for
C104H164Br4N16O24S4: C, 50.56; H, 6.69; Br, 12.94; N, 9.07; S,
arene tetrabromide (1,3-alternate-22). White powder, yield: 2′-{(ethoxycarbonyl[S-methyl]methyl)amidocarbonylmethyl})-
0.31 g (92%). Mp: 118 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) ammoniumethyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]-
3
δ 1.18 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 1.20 (s, 36H, arene tetrabromide (1,3-alternate-25). White powder, yield:
3
(CH3)3C), 1.32 (d, JHH = 7.3 Hz, 12H, CH3CH), 1.95 (m, 8H, 0.31 g (93%). Mp: 118 °C; 1H NMR (400 MHz, 298 K, DMSO-d6)
3
NHCH2CH2CH2N+), 3.17 (m, 8H, NHCH2CH2CH2N+), 3.22 (s, δ 1.19 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 1.22 (s, 36H,
3
3
24H, (CH3)2N+), 3.55 (m, 8H, NHCH2CH2CH2N+), 3.99 (s, 8H, (CH3)3C), 1.32 (d, JHH = 7.3 Hz, 12H, CH3CH), 1.34 (t, JHH
=
OCH2CO), 4.10 (q, JHH = 7.1 Hz, 8H, CH3CH2O–), 4.16 (s, 8H, 7.2 Hz, 24H, CH3CH2N+), 3.47 (m, 8H, NHCH2CH2N+),
N+CH2CO), 4.29 (m, 4H, CH3CH), 7.59 (s, 8H, ArH), 8.53 (br.s, 3.51–3.59 (m, 24H, N+CH2CH3, NHCH2CH2N+), 4.09 (s, 8H,
4H, NHCH2CH2CH2N+), 9.03 (br.s, 4H, CONH); 13C NMR N+CH2CO), 4.09–4.11 (m, 16H, OCH2CO, CH3CH2O–), 4.29 (m,
(100 MHz, DMSO-d6) δ 171.95, 167.16, 163.12, 157.21, 146.19, 4H, CH3CH), 7.60 (s, 8H, ArH), 8.27 (br.s, 4H, NHCH2CH2N+),
133.00, 127.66, 70.94, 62.56, 61.67, 60.77, 51.21, 48.13, 35.77, 9.18 (br.s, 4H, CONH); 13C NMR (100 MHz, DMSO-d6)
33.79, 30.76, 22.59, 16.52, 13.99; IRνmax 1157 (COC), 1676 δ 172.07, 168.53, 163.05, 157.69, 146.60, 133.71, 127.89, 71.05,
(CvO), 2958, 3193 (N–H); ESI: calcd for [M − 4 Br−]4+ m/z = 61.32, 56.87, 56.29, 55.71, 48.45, 34.51, 32.49, 31.36, 17.09,
3
480.6, found m/z
C96H152Br4N12O20S4: C, 51.42; H, 6.83; Br, 14.25; N, 7.50; S, ESI: calcd for [M − 4 Br−]4+ m/z = 494.7, found m/z = 494.5; El.
5.72. Found: C, 51.53; H, 6.59; Br, 14.53; N, 7.10; S, 5.31. Anal. Calcd for C100H160Br4N12O20S4: C, 52.26; H, 7.02; Br,
=
480.5; El. Anal. Calcd for 14.49, 7.92; IRνmax 1157 (COC), 1676 (CvO), 2964, 3185 (N–H);
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl- 13.91; N, 7.31; S, 5.58. Found: C, 52.12; H, 6.92; Br, 13.40; N,
2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammoniu- 7.56; S, 5.38.
methyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene
General procedure for the synthesis of the compounds 26–29
tetrabromide (1,3-alternate-23). White powder, yield: 0.34 g
(93%). Mp: 114 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.27 In a round bottom flask equipped with a magnetic stirrer,
(t, 3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.29 (s, 36H, (CH3)3C), 1.48 compounds 17, 23 and 14, 20 (0.46 × 10−3 mol) were dissolved
3
(t, JHH = 7.0 Hz, 24H, CH3CH2N+), 3.61–3.67 (m, 24H, in 10 ml of acetonitrile. Silver nitrate (1.84 × 10−3 mol) was
3
CH3CH2N+, NHCH2CH2N+), 3.91 (d, JHH = 5.7 Hz, 8H, added. The reaction mixture was refluxed for 10 h. Silver
NHCH2CO), 3.95 (m, 8H, NHCH2CH2N+), 4.08 (s, 8H, bromide was filtered. The solvent was removed under reduced
3
OCH2CO), 4.14 (q, JHH = 7.1 Hz, 8H, CH3CH2O–), 4.68 (s, 8H, pressure. The precipitate was dried under reduced pressure
N+CH2CO), 7.48 (s, 8H, ArH), 7.53 (br. s, 4H, NHCH2CH2N+), over phosphorus pentoxide.
3
9.60 (t, JHH = 5.7 Hz, 4H, NHCH2CO); 13C NMR (100 MHz,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl-
CDCl3) δ 169.88, 168.66, 163.50, 156.34, 147.50, 131.35, 126.92, 2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammoniu-
70.51, 61.49, 57.30, 56.45, 55.94, 41.05, 34.44, 33.54, 31.41, methyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene
14.18, 8.16; IRνmax 1199 (COC), 1678 (CvO), 2962, 3190 (N–H); tetranitrate (cone-26). White powder, yield: 0.09 g (98%). Mp:
ESI: calcd for [M − 4 Br−]4+ m/z = 480.6, found m/z = 480.5; El. 112 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.07 (s, 36H,
3
3
Anal. Calcd for C96H152Br4N12O20S4: C, 51.42; H, 6.83; Br, (CH3)3C), 1.19 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 1.28 (t, JHH
14.25; N, 7.50; S, 5.72. Found: C, 51.11; H, 6.78; Br, 14.51; N, = 7.0 Hz, 24H, CH3CH2N+), 3.54 (m, 8H, NHCH2CH2N+), 3.55
3
7.16; S, 5.83.
(q, JHH
=
7.0 Hz, 16H, CH3CH2N+), 3.63 (m, 8H,
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl- NHCH2CH2N+), 3.94 (d, 3JHH = 5.7 Hz, 8H, NHCH2CO), 4.10 (q,
2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl)amidocarb- 3JHH = 7.1 Hz, 8H, CH3CH2O–), 4.11 (s, 8H, N+CH2CO), 4.84 (s,
3
onylmethyl})ammoniumethyl)carbamoylmethoxy]-2,8,14,20- 8H, OCH2CO), 7.40 (s, 8H, ArH), 8.80 (t, JHH = 4.8 Hz, 4H,
tetrathiacalix[4]arene tetrabromide (1,3-alternate-24). White NHCH2CH2N+), 9.10 (t, JHH = 5.7 Hz, 4H, NHCH2CO); 13C
3
1
powder, yield: 0.35 g (93%). Mp: 124 °C; H NMR (400 MHz, NMR (100 MHz, DMSO-d6) δ 168.96, 165.21, 163.60, 157.56,
3
298 K, DMSO-d6) δ 1.19 (t, JHH = 7.2 Hz, 12H, CH3CH2O–), 146.94, 134.56, 127.94, 74.05, 60.79, 56.36, 56.08, 54.95, 40.70,
1.21 (s, 36H, (CH3)3C), 1.31 (t, JHH = 7.1 Hz, 24H, CH3CH2N+), 33.91, 32.23, 30.73, 14.01, 7.37; IRνmax 1197 (COC), 1679
3
3.45 (m, 8H, NHCH2CH2N+), 3.51–3.58 (m, 24H, CH3CH2N+, (CvO), 2957, 3279 (N–H); ESI: calcd for [M − 2 NO3
]
m/z =
m/z =
− 2+
NHCH2CH2N+), 3.86 (br.s, 8H, NHCH2CO), 3.88 (br.s, 8H, 1023.3, [M − 3 NO3
]
m/z = 661.5, [M − 4 NO3 ]
− 3+
− 4+
3
NHCH2CO), 4.05 (s, 8H, OCH2CO), 4.09 (q, JHH = 7.1 Hz, 8H, 480.6, found m/z = 1023.1, 661.3, 480.6; El. Anal. Calcd for
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2015

View Article Online
Organic & Biomolecular Chemistry
Paper
− 2+
C96H152N16O32S4: C, 53.12; H, 7.06; N, 10.32; S, 5.91. Found: 3280 (N–H); ESI: calcd for [M − 2 NO3
]
m/z = 995.2, [M − 3
− 3+
− 4+
C, 53.43; H, 6.79; N, 9.92; S, 5.70.
NO3
]
m/z = 642.8, [M − 4 NO3
]
m/z = 466.6, found m/z =
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(2′,2′-diethyl- 995.0, 642.7, 466.6; El. Anal. Calcd for C92H144N16O32S4: C,
2′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammoniu- 52.26; H, 6.86; N, 10.60; S, 6.07. Found: C, 52.59; H, 6.97; N,
methyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene tetra- 10.74; S, 6.27.
nitrate (1,3-alternate-27). White powder, yield: 0.09 g (98%).
Mp: 112 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.19 (t,
3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.20 (s, 36H, (CH3)3C), 1.31 (t,
The study of the interaction of the synthesized thiacalix[4]-
arenes 26–29 with DNA by UV spectroscopy
3JHH = 7.0 Hz, 24H, CH3CH2N+), 3.47 (m, 8H, NHCH2CH2N+),
3
3.52–3.57 (m, 24H, CH3CH2N+, NHCH2CH2N+), 3.96 (d, JHH
=
=
3
5.7 Hz, 8H, NHCH2CO), 4.07 (s, 8H, OCH2CO), 4.11 (q, JHH
UV-vis spectra were recorded by using a “Shimadzu UV-3600”
7.0 Hz, 8H, CH3CH2O–), 4.12 (s, 8H, N+CH2CO), 7.59 (s, 8H, spectrometer; the cell thickness was 1 cm, slit width was 1 nm.
3
3
ArH), 7.60 (t, JHH = 4.8 Hz, 4H, NHCH2CH2N+), 9.10 (t, JHH
=
The experiments were performed in 5 mM Tris-HCl buffer (pH
5.7 Hz, 4H, NHCH2CO); 13C NMR (100 MHz, DMSO-d6) 7.5). The DNA concentration was 0.019 mg ml−1, the concen-
δ 169.11, 163.57, 156.90, 153.40, 146.11, 133.04, 127.44, 74.38, tration of receptors was 10−4 M. The recording of the absorp-
60.72, 56.45, 55.09, 45.76, 40.80, 33.77, 31.83, 30.84, 14.06, tion spectra of the mixtures of DNA with thiacalixarenes was
7.23; IRνmax 1199 (COC), 1681 (CvO), 2960, 3266 (N–H); ESI: carried out in 1 hour after mixing the solutions at 20 °C.
− 2+
− 3+
calcd for [M − 2 NO3
]
m/z = 1023.3, [M − 3 NO3
]
m/z =
− 4+
661.5, [M − 4 NO3
]
m/z = 480.6, found m/z = 1023.0, 661.4,
480.7; El. Anal. Calcd for C96H152N16O32S4: C, 53.12; H, 7.06;
N, 10.32; S, 5.91. Found: C, 53.49; H, 6.86; N, 10.47; S, 5.59.
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl-
Determination of the hydrodynamic size of the particles
by DLS
3′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammonium- The particle size was determined by a Zetasizer Nano ZS
propyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene instrument at 20 °C. The instrument contains a 4 mW He–Ne
tetranitrate (cone-28). White powder, yield: 0.09 g (97%). Mp: laser operating at a wavelength of 633 nm and incorporates
113 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.08 (s, 36H, noninvasive backscatter optics (NIBS). The measurements were
3
(CH3)3C), 1.19 (t, JHH = 7.1 Hz, 12H, CH3CH2O–), 1.94 (m, 8H, performed at a detection angle of 173°, and the measurement
NHCH2CH2CH2N+), 3.18 (s, 24H, (CH3)2N+), 3.24 (m, 8H, position within the quartz cuvette was automatically deter-
NHCH2CH2CH2N+), 3.50 (m, 8H, NHCH2CH2CH2N+), 3.92 (d, mined by the software. The results were processed with the
3
3JHH = 5.7 Hz, 8H, NHCH2CO), 4.10 (q, JHH = 7.1 Hz, 8H, DTS (Dispersion Technology Software 4.20) software package.
CH3CH2O–), 4.12 (s, 8H, N+CH2CO), 4.80 (s, 8H, OCH2CO), Deionized water with resistivity >18.0 MΩ cm was used for the
7.40 (s, 8H, ArH), 8.51 (t, 3JHH
=
5.2 Hz, 4H, preparation of solutions. Deionized water was obtained using
3
NHCH2CH2CH2N+), 9.04 (t, JHH = 5.7 Hz, 4H, NHCH2CO); 13C a Millipore-Q purification system. The experiments were
NMR (100 MHz, DMSO-d6) δ 174.26, 173.56, 168.87, 163.20, carried out in 5 mM Tris-HCl buffer (pH 7.5). The buffer and
151.96, 139.67, 133.52, 79.31, 67.87, 67.09, 66.00, 56.47, 45.97, solutions of thiacalixarenes (10−3 M) were filtered through the
40.59, 39.15, 35.94, 27.72, 19.27; IRνmax 1199 (COC), 1672 nylon filters with a pore size of 450 nm. During the experi-
− 2+
(CvO), 2963, 3310 (N–H); ESI: calcd for [M − 2 NO3
]
m/z = ments, DNA concentration (0.048 mg ml−1) remained constant,
− 3+
− 4+
995.2, [M − 3 NO3
found m/z 995.0, 642.7, 466.5; El. Anal. Calcd for determination of the particle sizes was carried out in 1 hour
C92H144N16O32S4: C, 52.26; H, 6.86; N, 10.60; S, 6.07. Found: C, after sample preparation. To assess the kinetic stability of the
52.23; H, 6.83; N, 10.09; S, 5.93. systems, the measurements were also carried out under
]
m/z = 642.8, [M − 4 NO3
]
m/z = 466.6, concentration of receptors varied from 10−3 to 10−6 M. The
=
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrakis[(N-(3′,3′-dimethyl- similar conditions after 3 and 5 hours.
3′-{(ethoxycarbonylmethyl)amidocarbonylmethyl})ammonium-
propyl)carbamoylmethoxy]-2,8,14,20-tetrathiacalix[4]arene tetra-
nitrate (1,3-alternate-29). White powder, yield: 0.09 g (96%).
Determination of the shape and the size of the particles
by TEM
Mp: 113 °C; 1H NMR (400 MHz, 298 K, DMSO-d6) δ 1.19 (t,
3JHH = 7.1 Hz, 12H, CH3CH2O–), 1.20 (s, 36H, (CH3)3C), 1.94
(m, 8H, NHCH2CH2CH2N+), 3.17 (m, 8H, NHCH2CH2CH2N+), Imaging was carried out with a Carl Zeiss Merlin scanning
3.20 (s, 24H, (CH3)2N+), 3.51 (m, 8H, NHCH2CH2CH2N+), 3.95 electron microscope. Images were processed with a STEM
3
(d, JHH = 5.8 Hz, 8H, NHCH2CO), 4.00 (s, 8H, OCH2CO), 4.10 detector on a 300 mesh copper grid coated with Formvar.
3
(q, JHH = 7.1 Hz, 8H, CH3CH2O–), 4.13 (s, 8H, N+CH2CO), 7.60 Probe preparation was carried out using a negative staining
3
(s, 8H, ArH), 8.03 (t, JHH = 5.6 Hz, 4H, NHCH2CH2CH2N+), protocol with 2% uranyl acetate solution. The DNA concen-
3
9.04 (t, JHH = 5.8 Hz, 4H, NHCH2CO); 13C NMR (100 MHz, tration was 0.048 mg ml−1, the concentration of thiacalix[4]-
DMSO-d6) δ 168.77, 167.24, 163.84, 156.92, 145.96, 132.96, arene 28 was 10−5 M. The recording of the images of the
127.46, 70.96, 62.44, 61.67, 60.73, 51.31, 40.65, 35.96, 33.88, mixtures of DNA with thiacalixarenes was carried out in 1 hour
30.73, 22.51, 13.88; IRνmax 1197 (COC), 1679 (CvO), 2962, after mixing the solutions at 20 °C.
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.

View Article Online
Paper
Organic & Biomolecular Chemistry
24 O. Hudecek, P. Curinova, J. Budka and P. Lhotak, Tetra-
hedron, 2011, 67, 5213–5218.
Acknowledgements
Financial support by the Russian Foundation for Basic 25 M. M. Conn and J. Rebek Jr., Chem. Rev., 1997, 97, 1647–
Research (Grants 15-03-02877 and 13-03-12055 ofi_m) is grate-
fully acknowledged.
1668.
26 B. Linton and A. D. Hamilton, Chem. Rev., 1997, 97, 1669–
1680.
27 U. Ocak, M. Ocak and R. A. Bartsch, Inorg. Chim. Acta,
2012, 381, 44–57.
28 A. Acharya, B. Ramanujam, J. P. Chinta and C. P. Rao,
J. Org. Chem., 2011, 76, 127–137.
Notes and references
1 J. M. Lehn, Science, 2002, 295, 2400–2403.
2 J. M. Lehn, Supramolecular Chemistry: Concepts and Pers- 29 J. De Mendoza, Chem. – Eur. J., 1998, 4, 1373–1377.
pectives, Wiley-VCH, New York, NY, 1995. 30 J. Rebek Jr., Acc. Chem. Res., 1999, 32, 278–286.
3 J. W. Steed and J. L. Atwood, Supramolecular Chemistry, 31 J. L. Atwood, J. E. D. Davies, D. D. MacNicol, F. Vogtle,
John Wiley Hoboken, NJ, 2nd edn, 2009.
4 J. L. Atwood and J. W. Steed, Organic Nanostructures, Wiley-
VCH, Weinheim, 2008.
5 I. I. Stoikov, E. A. Yushkova, I. S. Antipin and
A. I. Konovalov, J. Nanopart. Res., 2011, 13, 6603–6611.
6 H.-J. Schneider, L. Tianjun, M. Sirish and V. Malinovsky,
Tetrahedron, 2002, 58, 779–786.
J. M. Lehn and G. W. Gokel, Comprehensive Supramolecular
Chemistry, Pergamon, London, 1996.
32 G. Yu, Y. Ma, C. Han, Y. Yao, G. Tang, Z. Mao, C. Gao and
F. Huang, J. Am. Chem. Soc., 2013, 135, 10310–10313.
33 I. I. Stoikov, E. A. Yushkova, A. Y. Zhukov, I. Zharov,
I. S. Antipin and A. I. Konovalov, Tetrahedron, 2008, 64,
7112–7121.
7 H.-J. Schneider, Angew. Chem., Int. Ed., 2009, 48, 3924– 34 I. I. Stoikov, E. A. Yushkova, A. Y. Zhukov, I. Zharov,
3977.
I. S. Antipin and A. I. Konovalov, Tetrahedron, 2008, 64,
7489–7497.
35 E. A. Yushkova and I. I. Stoikov, Langmuir, 2009, 25, 4919–
4928.
36 E. A. Yushkova, I. I. Stoikov, J. B. Puplampu, I. S. Antipin
and A. I. Konovalov, Langmuir, 2011, 27, 14053–
14064.
37 E. A. Yushkova, I. I. Stoikov, A. Y. Zhukov, J. B. Puplampu,
I. K. Rizvanov, I. S. Antipin and A. I. Konovalov, RSC Adv.,
2012, 2, 3906–3919.
8 I. Piantanida, B. S. Palm, P. Cudic, M. Zinic and
H.-J. Schneider, Tetrahedron Lett., 2001, 42, 6779–6783.
9 I. Piantanida, B. S. Palm, P. Cudic, M. Zinic and
H.-J. Schneider, Tetrahedron, 2004, 60, 6225–6231.
10 D. K. Chand, H.-J. Schneider, J. A. Aguilar, F. Escarti,
E. Garcıa-Espan and S. V. Luis, Inorg. Chim. Acta, 2001, 316,
71–78.
11 H.-J. Schneider, Eur. J. Med. Chem., 2008, 43, 2307–2315.
12 N. Lomadze and H.-J. Schneider, Tetrahedron, 2005, 61,
8694–8698.
38 R. Kumar, Y. O. Lee, V. Bhalla, M. Kumar and J. S. Kim,
Chem. Soc. Rev., 2014, 43, 4824–4870.
39 C. D. Gutsche, Calixarenes Revisited. In Monographs in
Supramolecular Chemistry, RSC, London, 1998.
13 S. Negi and H.-J. Schneider, Tetrahedron Lett., 2002, 43,
411–414.
14 E. Da Silva, F. Nouar, M. Nierlich, B. Rather,
M. J. Zaworotko, C. Barbey, A. Navaza and A. W. Coleman, 40 N. Iki and S. Miyano, J. Inclusion Phenom. Macrocyclic
Cryst. Eng., 2003, 6, 123–135. Chem., 2001, 41, 99–105.
15 E. Da Silva and A. W. Coleman, Tetrahedron, 2003, 59, 41 P. Lhotak, Eur. J. Org. Chem., 2004, 1675–1692.
7357–7364.
42 N. Morohashi, F. Narumi, N. Iki, T. Hattori and S. Miyano,
Chem. Rev., 2006, 106, 5291–5316.
43 H. Kumagai, M. Hasegawa, S. Miyanari, Y. Sugawa, Y. Sato,
T. Hori, S. Ueda, H. Kamiyama and S. Miyano, Tetrahedron
Lett., 1997, 38, 3971–3972.
44 I. I. Stoikov, V. A. Smolentsev, I. S. Antipin, W. D. Habicher,
M. Gruner and A. I. Konovalov, Mendeleev Commun., 2006,
16, 294–297.
16 P. Shahgaldian, E. Da Silva, A. W. Coleman, B. Rather and
M. J. Zaworotko, Int. J. Pharm., 2003, 253, 23–38.
17 M. Lamouchi, E. Jeanneau, R. Chiriac, D. Ceroni,
F. Meganem, A. Brioude, A. W. Coleman and C. Desroches,
Tetrahedron Lett., 2012, 53, 2088–2090.
18 E. Da Silva, P. Shahgaldian and A. W. Coleman,
Int. J. Pharm., 2004, 273, 57–62.
19 P. Shahgaldian, A. W. Coleman and V. I. Kalchenko, Tetra- 45 I. I. Stoikov, A. Y. Zhukov, M. N. Agafonova, R. R. Sitdikov,
hedron Lett., 2001, 42, 577–579.
20 O. Kundrat, V. Eigner, P. Curinov, J. Kroupa and P. Lhotak,
Tetrahedron, 2011, 67, 8367–8372.
21 J. Kroupa, I. Stibor, M. Pojarova, M. Tkadlecova and
P. Lhotak, Tetrahedron, 2008, 64, 10075–10079.
22 K. Flidrova, M. Tkadlecova, K. Lang and P. Lhotak, Tetra-
hedron Lett., 2012, 53, 678–680.
23 M. Yilmaz and S. Erdemir, Turk. J. Chem., 2013, 37, 558–
585.
I. S. Antipin and A. I. Konovalov, Tetrahedron, 2010, 66,
359–367.
46 I. I. Stoikov, A. A. Yantemirova, R. V. Nosov, I. K. Rizvanov,
A. R. Julmetov, V. V. Klochkov, I. S. Antipin, A. I. Konovalov
and I. Zharov, Org. Biomol. Chem., 2011, 9, 3225–
3234.
47 I. I. Stoikov, A. A. Yantemirova, R. V. Nosov, A. R. Julmetov,
V. V. Klochkov, I. S. Antipin and A. I. Konovalov, Mendeleev
Commun., 2011, 21, 41–43.
Org. Biomol. Chem.
This journal is © The Royal Society of Chemistry 2015

View Article Online
Organic & Biomolecular Chemistry
Paper
48 M. Yamada, Y. Ootashiro, Y. Kondo and F. Hamada, Tetra- 60 G. Zuber, L. Zammut-Italiano, E. Dauty and J. P. Behr,
hedron Lett., 2013, 54, 1510–1514. Angew. Chem., Int. Ed., 2003, 42, 2666–2669.
49 E. V. Ukhatskaya, S. V. Kurkov, S. E. Matthews, A. E. Fagui, 61 C. Chittimalla, L. Zammut-Italiano, G. Zuber and J. P. Behr,
C. Amiel, F. Dalmas and T. Loftsson, Int. J. Pharm., 2010,
402, 10–19.
50 G. Yu, K. Jie and F. Huang, Chem. Rev., 2015, 115, DOI:
10.1021/cr5005315.
51 S. Dong, B. Zheng, F. Wang and F. Huang, Acc. Chem. Res.,
2014, 47, 1982–1994.
J. Am. Chem. Soc., 2005, 127, 11436–11441.
62 E. Dauty, J. S. Remy, T. Blessing and J. P. Behr, J. Am. Chem.
Soc., 2001, 123, 9227–9234.
63 E. A. Andreyko, P. L. Padnya and I. I. Stoikov, Colloids Surf.,
A, 2014, 454, 74–83.
64 S. Arimori, T. Nagasaki and S. Shinkai, J. Chem. Soc., Perkin
Trans. 2, 1995, 679–683.
52 R.
V.
Rodik,
A.
S.
Klymchenko,
N.
Jain,
S. I. Miroshnichenko, L. Richert, V. I. Kalchenko and 65 E. A. Andreyko, P. L. Padnya, R. R. Daminova and
Y. Mely, Chem. – Eur. J., 2011, 17, 5526–5538. I. I. Stoikov, RSC Adv., 2014, 4, 3556–3565.
53 Y. Shi and H. J. Schneider, J. Chem. Soc., Perkin Trans. 2, 66 E. D. Kaverzneva, V. K. Zvorykina and V. V. Kiseleva, Bull.
1999, 1797–1803.
54 A. Dondoni, M. Kleban, X. Hu, A. Marra and H. D. Banks,
J. Org. Chem., 2002, 14, 4722–4733.
55 S. Kolusheva, R. Zadmard, T. Schrader and R. Jelinek,
J. Am. Chem. Soc., 2006, 41, 13592–13598.
56 A. Verma and V. M. Rotello, Chem. Commun., 2005, 303–
312.
57 B. Khairutdinov, E. Ermakova, A. Sitnitsky, I. Stoikov and
Y. Zuev, J. Mol. Struct., 2014, 1074, 126–133.
Acad. Sci. USSR, Div. Chem. Sci. (English Translation), 1970,
10, 2157–2166.
67 Y.-Y. Zhu, H.-P. Yi, C. Li, X.-K. Jiang and Z.-T. Li, Cryst.
Growth Des., 2008, 8, 1294–1300.
68 S. W. Feil, G. K. Koyanagi, J. Anichina and D. K. Bohme,
J. Phys. Chem., 2008, 112, 10375–10381.
69 D. Freifelder, Physical Blochemistry, Applications to Biochem-
istry and Molecular Biology, W. H. Freeman and Company,
San Francisco, 2nd edn, 1982.
58 R. Lalor, J. L. DiGesso, A. Mueller and S. E. Matthews, 70 R. S. Diasa, C. C. Pais, M. G. Miguela and B. Lindman, Col-
Chem. Commun., 2007, 4907–4909. loids Surf., A, 2004, 250, 15–131.
59 M. K. Rauf, R. Mushtaq, A. Badshah, R. Kingsford-Adaboh, 71 N. Iki, F. Narumi, T. Fujimoto, N. Morohashi and
J. J. E. K. Harrison and H. Ishida, J. Chem. Crystallogr.,
2013, 43, 144–150.
S. Miyano, J. Chem. Soc., Perkin Trans. 2, 1998, 2745–
2750.
This journal is © The Royal Society of Chemistry 2015
Org. Biomol. Chem.