Versatile chiroptics of peptide-induced assemblies of metalloporphyrins

Article abstract of DOI:10.1039/b920058d

Zinc porphyrin functionalized with double long-chain alkylated l-glutamide (GTPP-Zn) was synthesized for the first time, and its self-assembling behaviour was investigated in nonpolar organic solvents. The uniqueness of this functionalized porphyrin is characterized by its drastic colour change from dark green to purple via the formation of chirally stacked structures through selective axial coordination on zinc with pyridine derivatives. In this paper, we report the versatility of the GTPP-Zn assembly process as a stimuli-responsive chiroptical switching system and describe the remarkable ligand-specific induction of secondary chirality accompanied by aggregation morphological change.

Full text of DOI:10.1039/b920058d

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PAPER
www.rsc.org/obc | Organic & Biomolecular Chemistry
Versatile chiroptics of peptide-induced assemblies of metalloporphyrins†
Hirokuni Jintoku,a Takashi Sagawa,b Tsuyoshi Sawada,a Makoto Takafujia and Hirotaka Ihara*a
Received 25th September 2009, Accepted 30th November 2009
First published as an Advance Article on the web 14th January 2010
DOI: 10.1039/b920058d
Zinc porphyrin functionalized with double long-chain alkylated L-glutamide (GTPP-Zn) was
synthesized for the first time, and its self-assembling behaviour was investigated in nonpolar organic
solvents. The uniqueness of this functionalized porphyrin is characterized by its drastic colour change
from dark green to purple via the formation of chirally stacked structures through selective axial
coordination on zinc with pyridine derivatives. In this paper, we report the versatility of the GTPP-Zn
assembly process as a stimuli-responsive chiroptical switching system and describe the remarkable
ligand-specific induction of secondary chirality accompanied by aggregation morphological change.
Introduction
Chiroptics is important for the investigation of chiral substances in
nature. These optical techniques can be used to create complicated
nanostructures from chiral molecules such as amino acids and
sugars. Recently, chiroptical materials have come to be used
in diverse fields such as analytical chemistry, photochemistry,
and materials chemistry.1 Thus, nanofabrication with chiroptical
molecules holds significant promise as a method to realize
molecular devices with possible applications such as chiroptical
switches, films, and molecular motors.2
Furthermore, molecular organogel systems have been widely
investigated as unique organic media in which gelation occurs
through the formation of a three-dimensional nanofibrillar net-
work of self-assembling low-molecular-weight compounds such as
peptide-, sugar- and cholesterol-based lipophilic compounds.3 The
fibrillar aggregates are often chirally ordered and show secondary
chirality with strong CD signals in organic media. Successfully
synthesized examples include pyrene-, perylene-, isoquinoline-,
triazine- and porphyrin-containing organogel systems.4 Therefore,
a molecular organogel system is an attractive candidate for
chiroptical materials.
On the basis of these viewpoints, we focus on chiroptical
porphyrin derivatives with the aim of creating stimuli-responsive
soft materials. Herein, we introduce a novel chiroptical molecule
(GTPP-Zn) containing a zinc porphyrin unit that is functionalized
with a double long-chain alkylated L-glutamide derivative as a
promoter for chiral assembly (Scheme 1). It is expected that chiral
stacking of porphyrin units can not only be induced through
intermolecular hydrogen bonding between the L-glutamide units5
but also be tuned by axial coordination on zinc.6
Scheme 1 L-Glutamide-derivatives functionalized tetraphenylporphyrin.
exhibiting a remarkable ligand-specific spectral shift, induction
of secondary chirality, and dynamic morphological change.
Results and discussion
Solubility change of the porphyrin derivative by zinc-insertion
The free-base tetraphenylporphyrin (TPP) derivative functional-
ized with L-glutamide-derived lipid (GTPP) showed almost no
solubility in nonpolar organic solvents such as diethyl ether,
cyclohexane and n-hexane. However, we observed that this limited
solubility promotes gelation in organic media through nanofib-
rillar aggregation when solvent polarity is adjusted with polar
solvents such as THF and DMF.7 This phenomenon is a form of
low-molecular-mass organogelation.8
Interestingly, zinc insertion into GTPP resulted in remarkably
improved solubility in nonpolar organic solvents while the gelation
ability almost disappeared.† Good solubility is a significant advan-
tage in the manufacture of soft materials. Reduction of the solvent
absorption, especially in the UV region, is also important. As
shown in Fig. 1a, a deep pink-coloured clear solution (0.25 mM)
was obtained without any gelation at 20 ◦C when zinc-containing
GTPP (GTPP-Zn) was dissolved in cyclohexane. The lmax of the
glutamide-unit-free TPP moiety was located at 430 nm as a single
peak, which was longer by 13 nm than that in zinc-containing TPP
(Fig. 1a). This indicates aggregation of GTPP-Zn in cyclohexane.
To address this observation, the following were examined: (1) lmax
of GTPP-Zn shifted from 430 nm to 417 nm by high dilution
such as to 1 mM. The spectral pattern with lmax of 417 nm is
In this paper, we report the versatility of the GTPP-Zn self-
assembling system as a stimuli-responsive chiroptical switch,
aDepartment of Applied Chemistry & Biochemistry, Kumamoto University,
2-39-1 Kurokami, Kumamoto, 860-8555, Japan. E-mail: ihara@kumamoto-
u.ac.jp; Fax: (+81) 96 3423662; Tel: (+81) 96 3423661
bInstitute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto, 611-
0011, Japan. E-mail: t-sagawa@iae.kyoto-u.ac.jp; Fax: (+81) 774 383508;
Tel: (+81) 774 384580
† Electronic supplementary information (ESI) available: Solubility and
UV-visible, circular dichroism (CD), 1H-NMR and FT-IR spectra of
GTPP-Zn. See DOI: 10.1039/b920058d
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UV-visible spectrum. As shown in Fig. 3a, four peak maxima are
observed at 400, 427, 435 and 459 nm. Here, we initially focus on
the peak maximum at 427 nm because TPP-Zn shows a simple
lmax shift from 417 nm to 427 nm by addition of an equimolar
amount of pyridine (Fig. 2g). This can be explained by formation
of a typical one-to-one complex via a nitrogen–zinc coordination.11
A similar lmax of 427 nm was also observed in GTPP-Zn in the
presence of a large excess (2000 equimolar) of pyridine (Fig. 2c
and 3a). This indicates that pyridine can be an effective solvent for
GTPP-Zn as well as a ligand for coordination. In support of this,
when pyridine-d5 was used as a solvent in NMR spectroscopy, no
peak-broadening phenomenon was observed, indicating complete
disaggregation of an L-glutamide derivative. This is probably due
to inhibition by pyridine of intermolecular interaction such as
hydrogen bonding. Therefore, we conclude that a peak maximum
at 427 nm can be attributed to axial coordination of pyridine on
GTPP-Zn without any aggregation.
The detailed concentration dependency of pyridine is shown
in Fig. 4. Neither significant colour nor spectral changes were
observed in the presence of 0–4 equiv. of pyridine. It seems that
the colour change to dark green (Fig. 2b) is specifically induced
in the presence of 5–100 equiv. of pyridine with an increase in
the absorbance at 459 nm (Abs459). Further addition of pyridine
changes the colour to purple (Fig. 2c) with a decrease in Abs459
.
However, we found that a greenish colour was observed even in
a one-to-one mixture of GTPP-Zn and an equimolar amount
of pyridine. This was obtained by the following special procedure:
when the one-to-one mixture was aged at 60 ◦C for 10 min and then
allowed to stand at 25 ◦C for two days. Therefore, it is estimated
that a one-to-one complex can be produced but is delayed due to
the aggregation.
Fig. 1 UV-visible (a) and CD spectra (b) of TPP-Zn (red line) and
GTPP-Zn (blue line) in cyclohexane (0.25 mM) at 20 ◦C.
similar to that in the Soret band of TPP-Zn.† (2) At 10 mM, a
reversible lmax shift between 430 nm and 417 nm was observed
in the temperature range between 10 ◦C and 60 ◦C.† (3) The CD
spectra of GTPP-Zn showed large Cotton effects ([q]433 = 8 ¥
105 deg cm2 dmol-1 at 0.25 mM at 20 ◦C) around the Soret band
(Fig. 1b), indicating chiral ordering of a porphyrin moiety while
almost no CD was observed at 10 mM at 60 ◦C or in a highly
diluted solution such as 1 mM at 10 ◦C. These results indicate
that GTPP-Zn in cyclohexane can disperse as certain aggregates
through the amide bonds and also undergoes both lyotropic and
thermotropic aggregate–monomer phase transitions.
Aggregation structure of the greenish complex
The greenish complex with lmax of 459 nm should be furthermore
discussed in detail because it is expected to be a model system
for a natural chlorophyll system.10 As shown in Fig. 3b, the
complexation with pyridine was accompanied by an extreme
enhancement of CD intensity at around 459 nm. The largest value
can be detected in the concentration range of 5–100 equiv. of
pyridine and exceeds 1 ¥ 107 deg cm2 dmol-1 in [q]462 (Fig. 3b),
which was 20 times larger than that of the original GTPP-Zn
aggregates. On the other hand, a decrease of CD intensity was
observed in free-base GTPP (15 to 0.08 ¥ 104 deg cm2 dmol-1).
Therefore, it is considered that the axial coordination of pyridine
on GTPP-Zn promotes a drastic change of chirally ordered
structures as well as strong stacking among the porphyrin moieties.
On the other hand, the Q band absorptions are also help to
understand the molecular aggregation of GTPP-Zn. It is known
that an absorption spectrum of normal metalloporphyrin shows
the other two absorption maxima called the Q or a and b bands,
which are found between 500 and 650 nm.11 As shown in Fig. 3a,
the complexation with pyridine induced a relative intensity change
of the a and b bands (ea/eb) as well as a lmax shift. Generally, the
value of ea/eb and the red shift of a and b bands are qualitative
correlated with the strength of a coordination bonding of zinc–
ligand bond and stability of the complex.11 Table 1 summarizes
the observed a and b bands under various conditions. It is
clear that the complexation with pyridine increases ea/eb, but
Chiroptical response to pyridine doping on GTPP-Zn
Addition of pyridine as a ligand to GTPP-Zn induced an amazing
colour change from deep pink to dark green while TPP-Zn showed
only a slight change from deep pink to purple, and almost no
colour change was observed in free-base GTPP. The typical results
of the colour changes are summarized in Fig. 2. Hu et al. reported
that tetra(4-pyridyl)porphyrin formed greenish nanoprisms (rod-
like nanocrystals) with assistance from cetyltrimethylammonium
bromide as a cationic micellar compound,9 but there are few
similar findings in reports of other synthetic porphyrin systems.10
Therefore, these observations suggest that pyridine promotes a
change in aggregation morphology of GTPP-Zn into strongly
stacked structures such as nanocrystals. A detailed discussion
appears in the next section.
The colour change of GTPP-Zn with 10 equiv. of pyridine was
accompanied by complicated splitting of the Soret band in the
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Fig. 2 Library of colour changes of the porphyrin derivatives (0.5 mM) in cyclohexane at 20 ◦C. (a) GTPP-Zn, (b) GTPP-Zn with pyridine (10 equiv.),
(c) GTPP-Zn with pyridine (2000 equiv.), (d) GTPP-Zn in chloroform, (e) GTPP-Zn with pyridine (10 equiv.) in chloroform, (f) TPP-Zn, and (g) TPP-Zn
with pyridine (10 equiv.).
Table 1 Absorption spectral date of TPP-Zn and GTPP-Zn
Porphyrina Guest molecule (equiv.) Solvent
b/nm a/nm ea/eb
TPP-Zn
None
Pyridine (10)
None
CHCl3
CHCl3
Cyclohexane 545
Cyclohexane 560
Toluene
Toluene
CHCl3
CHCl3
Cyclohexane 558
Cyclohexane 573
Cyclohexane 561
551
562
594
602
585
599
588
602
597
603
598
613
601
0.16
0.44
0.09
0.34
0.16
0.43
0.27
0.46
0.33
0.89
0.41
Pyridine (10)
Noneb
549
562
554
562
Pyridine (1)b
GTPP-Zn None
Pyridine (10)
None
Pyridine (10)
Pyridine (2000)
a Concentration of porphyrin: 0.25 mM b Date from reference 11.
Fig. 3 UV-visible (a) and CD (b) spectra of GTPP-Zn (0.25 mM) in
cyclohexane at 20 ◦C without pyridine (red broken line), with 10 equiv.
(blue line) and 2000 equiv. (black line) of pyridine.
the most remarkable lmax shifts and enhancement of the ea/eb
value were observed in the GTPP-Zn–pyridine complex. These
results indicate that the molecular stacking results in a remarkable
increase of the stability of the complex.
Fig. 4 Concentration dependency of molecular coefficient (e) at 459 nm
and molecular ellipticity ([q]] at 454 nm of GTPP-Zn (0.25 mM) with
pyridine (0 to 2000 equiv.) complex at 20 ◦C.
For 1H NMR spectroscopy, a sample of the GTPP-Zn–pyridine
complex was obtained by recrystallization from a concentrated
cyclohexane solution and successive washing with cyclohexane.
Analysis was performed in a chloroform-d solution. The resultant
1H NMR spectrum shows large upfield shifts of the proton
pyridine is formed by axial coordination. In addition, the binding
ratio of GTPP-Zn and pyridine was also estimated by the peak
areas of a chiral carbon in an L-glutamide moiety and m-H
in a coordinated pyridine, indicating a one-to-one complex of
GTPP-Zn and pyridine.†
o-H
m-H
resonances of the pyridyl ring (Dd
= 5.24 ppm, Dd
=
1.48 ppm) caused by the shielding effect of the porphyrin.12
This result supports that the complexation of GTPP-Zn with
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The IR spectra showed informative absorption shifts on the
amide bond.† The typical absorptions of GTPP-Zn with pyridine
in cyclohexane were located at 1632 cm-1 and 1550 cm-1 and were
attributedtoamidesIandII, respectively, whilenonbondingamide
I and II bands measured in a chloroform solution were found at
1652 cm-1 and 1525 cm-1, respectively. These results indicate that a
strong and ordered hydrogen bonding interaction derived from an
L-glutamide moiety is present for the aggregation of GTPP-Zn.13
A chirally stacked structure of the aggregates can be estimated
from a CD spectral pattern. The greenish complex showed a
typical splitting with a positive Cotton effect around 462 nm and
a negative Cotton effect around 454 nm (Fig. 3b). According to
Huang’s definition,6 this pattern can be assigned to a typical R-
chiral plane-to-plane ordering.
morphology are a minimum diameter of several nanometres and
a length of a couple of micrometres. This supports the spectral
estimation that the greenish aggregates of a one-to-one complex
of GTPP-Zn with pyridine would be based on nanocrystals. On
the other hand, no similar aggregation was observed in the TPP-
Zn–pyridine complex. Therefore, the L-glutamide moiety provides
as essential driving force for aggregation and ordering on the basis
of intermolecular hydrogen bonding interaction.
Selective chiroptical response on axial coordination
UV-visible and CD spectral responses of GTPP-Zn (0.25 mM)
were investigated for various pyridine derivatives such as
monoalkyl- and dialkylpyridines. As shown in Fig. 6, the obtained
UV-visible and CD spectra were distinctly different from each
other because of the chemical difference of pyridines such as (a) 4-
methylpyridine, (b) 3,5-dimethylpyridine, (c) 4-tert-butylpyridine,
and (d) 2,6-di-tert-butylpyridine, as typical examples. For example,
strong CD signals were induced by 4-methylpyridine, but the chiral
sense at around 450 nm was opposite that in pyridine. On the other
hand, 2,6-di-tert-butylpyridine induced few CD signals. It is clear
that the spectral patterns vary in lmax, sharpness, intensity, chiral
sense, and splitting pattern. In addition, the spectral response was
accompanied by a change of aggregation morphology. Typical
examples are shown in Fig. 7. Both 2,3- and 3,5-dimethylpyridine
induced nanofibrillar aggregation (Fig. 7b and 7c), but 2,6-
dimethylpyridine did not induce fibrillar structure but rather
globular-like structure (Fig. 7d). As compared with Fig. 5b, these
morphological changes are clearly different from that in pyridine
Induction of morphological change
As shown in Fig. 5a, only globular-like structures having diameters
of 300–500 nm were observed in the cast film prepared from a
cyclohexane solution containing 0.25 mM GTPP-Zn. It should
be noted that no staining reagent such as heavy metals was used
in the sample preparation, and therefore the good contrast of the
TEM image supports the existence of zinc ions in the aggregates.
This explains that the good solubility of GTPP-Zn in nonpolar
solvents is due to globular aggregation although free-base GTPP
forms nanofibrillar aggregates to make a gel.5
Fig. 5b shows that the complexation with pyridine induces
a drastic change of aggregation morphology from globular to
needle-like structures. The dimensions of the newly detected
Fig. 5 TEM images of GTPP-Zn (a) without and (b) with 10 equiv. of pyridine. The samples were prepared by casting from a 0.25 mM cyclohexane
solution and no staining regent was used.
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Fig. 7 (a) Photo image of the GTPP-Zn (1 mM) gel in cyclohexane
at 15 ◦C with 2,3-dimethylpyridine (100 equiv.). TEM images of the
GTPP-Zn aggregates with (b) 2,3-dimethylpyridine (100 equiv.), (c)
3,5-dimethylpyridine (10 equiv.), and (d) 2,6-dimethylpyridine (10 equiv.)
in the cast film prepared by 0.25 mM cyclohexane solution. (b) and (c)
were stained by 2.0 wt% ammonium molybdate.
Fig. 6 UV-visible and CD spectra of GTPP-Zn (0.25 mM) with 10 equiv.
of (a) 4-methylpyridine, (b) 3,5-dimethylpyridine, (c) 4-tert-butylpyridine,
and (d) 2,6-di-tert-butylpyridine in cyclohexane at 20 ◦C.
where needle-like aggregates were produced. As supporting this,
the complexes with 2,3- and 3,5-dimethylpyridine showed a
typical mass gelation behavior in 1 mM (Fig. 7a), although the
complexation with pyridine promotes the crystallization. These
results indicate that the coordination structures influence to the
macroscopic morphologies.
These results demonstrate the potential for applicability as a
sensing system through axial coordination. In this regard, further
detailed investigation was carried out by using 11 kinds of pyridine
derivatives as guest molecules. As summarized in Table 2, the lmax
shifts of the a and b bands, ea/eb, and the CD intensity were
apparently dependent on the guest molecules. Here, when the focus
is on the value of ea/eb and the relative CD intensity (Fig. 8), we
recognize that there are roughly two classifications in the response
pattern: one is to show the results with a weak CD strength as well
as a small ea/eb.
Fig. 8 Plot of ea/eb versus Dq values of GTPP-Zn (0.25 mM) with 10
equiv. of various guest molecules in cyclohexane at 20 ◦C. Numbers refer
to complexes in Table 2.
bulk of the guest molecules. The other one is a category showing
the increase of the CD intensity with the increase of the ea/eb value
although there is one exception in 3,5-dimethylpyridine. However,
this exception is probably related to the steric factor derived from
two methyl groups. The value of ea/eb is an indicator of the complex
stability, and therefore it is reasonable that the increase of ea/eb is
accompanied by an enhancement of chiral ordering, showing an
increase of CD strength.
These guest molecules are 2-alkyl and/or tert-butyl derivatives.
This strongly indicates that GTPP-Zn is very sensitive to the steric
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Table 2 Observed a and b bands and the CD intensities of GTPP-Zn with various guest molecules in cyclohexane at 20 ◦
C
[q]max
[q]min
Dq ([q]max - [q]min)
No.
Guest molecule
b/nm
a/nm
ea/eb
(106 deg cm2 dmol-1)
/106 deg cm2 dmol-1
1
2
3
4
5
6
7
8
None
Pyridine
4-Methylpyridine
3-Methylpyridine
3-Ethylpyridine
4-tert-Butylpyridine
2,3-Dimethylpyridine
2,4-Dimethylpyridine
2,5-Dimethylpyridine
2,6-Dimethylpyridine
3,4-Dimethylpyridine
3,5-Dimethylpyridine
2,6-Di-tert-butylpyridine
558
573
566
564
565
561
559
558
558
558
565
565
559
598
613
603
603
604
602
598
598
598
598
602
604
599
0.33
0.89
0.64
0.56
0.59
0.39
0.34
0.32
0.32
0.32
0.50
0.62
0.35
433 (0.8)
462 (15.9)
444 (4.5)
426 (3.3)
426 (6.2)
424 (0.8)
432 (0.4)
432 (0.4)
432 (0.5)
432 (0.5)
425 (2.4)
426 (2.7)
434 (0.6)
443 (0.7)
1.5
29.1
12.8
7.1
11.1
1.6
0.9
0.9
1.3
1.4
454 (13.2)
448 (8.3)
439 (3.8)
440 (4.9)
442 (0.8)
426 (0.5)
426 (0.5)
426 (0.8)
420 (0.9)
399 (1.3)
440 (3.2)
427 (0.5)
9
10
11
12
13
3.7
15.9
1.1
Concentration of GTPP-Zn: 0.25 mM, guest molecule: 2.5 mM (10 equiv.).
dried by a vacuum pump under reduced pressure. The accelerating
voltage of the TEM was 80 kV and the beam current was 40 A.
Conclusions
In this paper, we have described the synthesis of a new zinc-inserted
porphyrin lipid (GTPP-Zn) and the chiroptical response toward
pyridine derivatives. The following findings can be summarized:
(1) the solubility in a nonpolar solvent was fully modified by
insertion of zinc into GTPP compared with free-base GTPP. TEM
observations indicated that the solubility improvement was related
to a change in aggregation morphology from fibrils to globules. As
a result, GTPP-Zn showed lyotropic and thermotropic aggregate-
to-monomer transitions in nonpolar organic solvents such as
cyclohexane. (2) Axial coordination of pyridine on GTPP-Zn
induced new chirality in the Soret band as well as a drastic visible
spectral change. This is caused by induction of highly ordered
chiral stacking among the porphyrin moieties. (3) By investigation
of axial coordination with various pyridine derivatives, it was
confirmed that the resultant spectral patterns varied in intensity,
shift, and splitting. This indicates that GTPP-Zn has high
potential applicability as a multiresponsive molecular switching
device.
Zinc inserted porphyrin-lipid (GTPP-Zn)
Zinc inserted porphyrin (GTPP-Zn) was prepared by mixing a
solution of Zn(OAc)2 2H2O (0.17 g, 0.80 mmol) in methanol
(10 mL) and a solution of GTPP (0.3 g, 0.25 mmol), which was
obtained by the previously reported procedure7 in chloroform
(100 mL). The mixture solution was stirred for 6 h at room
temperature. The solution was concentrated in vacuo. The residue
was redissolved in chloroform, and the organic layer was washed
with water and dried with sodium sulfate. The solution was dried
in vacuo to give purple solids (196 mg, 72%). mp: 230.5–232.5 ◦C.
(Found: C, 74.56; H, 7.28; N, 8.21. C74H85N7O3Zn requires C,
74.95; H, 7.22; N, 8.27%). nmax(KBr)/cm-1 3395 and 3310 (NH),
2925 and 2852 (CH), 1647 (CO), 1523 (NH). dH (400 MHz; CDCl3;
Me4Si) 0.79–0.86 (6H, t, –CH3), 1.16–1.25 (40H, br, –(CH2)10–),
1.54 (2H, br, –CH2CO–), 1.75–1.91 (2H, br, –CH2–), 2.67–2.81
(4H, m, –NHCH2–), 3.46 (1H, q, –CH–), 5.56 (1H, br, NH), 6.28
(1H, br, NH), 7.45–7.51 (1H, br, NH), 7.74–7.76 (9H, m, ArH),
8.13–8.22 (10H, m, ArH), 8.80–8.94 (8H, m, ArH). MALDI TOF
MS (2,5–dihydroxybenzoic acid matrix): Calcd for C74H85N7O3Zn
1183.60, m/z = 1184.45 (M+).
Experimental
Materials and instrumentations
5-(4-Methoxycarbonylphenyl)-10,15,20-triphenyl-21H,23H-por-
phine and 5,10,15,20-tetraphenyl-21H,23H-porphine were pur-
chased from the Tokyo Chemical Industry. Reagent grade solvents
and Measurement grade solvent were purchased from Nacalai
tesque. N1,N5-didodecyl-L-glutamide (G) was synthesized by the
previously reported procedure5 with slight modification. 1H NMR
(400 MHz) spectra were recorded in CDCl3 with SiMe4 as an
internal standard with JNM-EX400 (JEOL). FT-IR spectra were
measured in a KBr method with FT/IR-4100 (JASCO). FT-IR
spectra of solution were obtained from 1 mM cyclohexane or
chloroform solutions. MALDI TOF-MS spectrum was recorded
on a Voyager RP (PerSeptiv Biosystem). UV-visible and CD
spectra were measured with V-560 (JASCO) and J725 (JASCO),
respectively. The solution was poured into a 0.1 mm, 1.0 mm and
10 mm quartz cell. TEM images were observed with JEM-2000X
(JEOL). The solution was cast in a carbon-coated copper grid and
Acknowledgements
This work was supported in part by a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science, Sports, and
Culture of Japan.
Notes and references
1 L. Yuan, R. Wang and D. H. Macartney, Tetrahedron: Asymmetry,
2007, 18, 483–487; D. Monti, L. L. Monica, A. Scipioni and G. Mancini,
New J. Chem., 2001, 25, 780–782; M. Mathews and N. Tamaoki, J. Am.
Chem. Soc., 2008, 130, 11409–11416; A. Shundo, J. Labuta, J. P. Hill,
S. Ishihara and K. Ariga, J. Am. Chem. Soc., 2009, 131, 9494–9495;
A. Patel, S. Fouace and J. H. G. Steinke, Anal. Chim. Acta, 2004, 504,
53–62.
2 B. L. Feringa, Acc. Chem. Res., 2001, 34, 504–513; M. Takafuji, A.
Ishiodori, T. Yamada, T. Sakurai and H. Ihara, Chem. Commun., 2004,
1122–1123.
This journal is
The Royal Society of Chemistry 2010
Org. Biomol. Chem., 2010, 8, 1344–1350 | 1349
©

View Article Online
3 Y.-C. Lin and R. G. Weiss, Macromolecules, 1987, 20, 414–417; J. H.
Van Esch and B. L. Feringa, Angew. Chem., Int. Ed., 2000, 39, 2263–
2266; N. Ide, T. Fukuda and T. Kunitake, Bull. Chem. Soc. Jpn., 1995,
68, 3423–3428; T. Shimizu, M. Masuda and H. Minamikawa, Chem.
Rev., 2005, 105, 1401–1443; M. Suzuki, T. Sato, A. Kurose, H. Shirai
and K. Hanabusa, Tetrahedron Lett., 2005, 46, 2741–2745; P. Xue, R.
Lu, D. Li, M. Jin, C. Tan, C. Bao, Z. Wang and Y. Zhao, Langmuir,
2004, 20, 11234–11239.
4 J.-H. Fuhrhop, C. Demoulin, C. Boettcher, J. Koning and U. Siggel,
J. Am. Chem. Soc., 1992, 114, 4159–4165; S. Tamaru, M. Nakamura, M.
Takeuchi and S. Shinkai, Org. Lett., 2001, 3, 3631–3634; F. Wu¨rthner,
Z. Chen, F. J. M. Hoeben, P. Osswald, C.-C. You, P. Jonkheijm, J. V.
Herrikhuyzen, A. P. H. J. Schenning, P. P. A. M. van der Schoot, E. W.
Meijer, E. H. A. Beckers, S. C. J. Meskers and R. A. J. Janssen, J. Am.
Chem. Soc., 2004, 126, 10611–10618; S. Cicchi, G. Ghini, S. Fallani,
A. Brandi, D. Berti, F. Betti and P. Baglioni, Tetrahedron Lett., 2008,
49, 1701–1705; H. Ihara, T. Sakurai, T. Yamada, T. Hashimoto, M.
Takafuji, T. Sagawa and H. Hachisako, Langmuir, 2002, 18, 7120–
7123.
5 H. Ihara, M. Yoshitake, M. Takafuji, T. Yamada, T. Sagawa, C.
Hirayama and H. Hachisako, Liq. Cryst., 1999, 26, 1021–1027.
6 X. Huang, B. H. Rickman, B. Borhan, N. Berova and K. Nakanishi,
J. Am. Chem. Soc., 1998, 120, 6185–6186; D. P. Cormode, S. S.
Murray, A. R. Cowley and P. D. Beer, Dalton Trans., 2006, 5135–
5140; J. P. Hill, Y. Wakayama, W. Schmitt, T. Tsuruoka, T. Nakanishi,
M. L. Zandler, A. L. McCarty, F. D’Souza, L. R. Milgrom and K.
Ariga, Chem. Commun., 2006, 2320–2322; Y. Li, T. Wang and M. Liu,
Soft Matter, 2007, 3, 1312–1317; N. C. Maiti, S. Mazumdar and N.
Periasamy, J. Phys. Chem. B, 1998, 102, 1528–1538; M. V. Rekharsky,
H. Yamamura, C. Inoue, M. Kawai, I. Osaka, R. Arakawa, K. Shiba,
A. Sato, Y. H. Ko, N. Selvapalam, K. Kim and Y. Inoue, J. Am. Chem.
Soc., 2006, 128, 14871–14880.
7 H. Jintoku, T. Sagawa, T. Sawada, M. Takafuji, H. Hachisako and H.
Ihara, Tetrahedron Lett., 2008, 49, 3987–3990.
8 P. Terech, R. G. Weiss, ed. Chem. Rev., 1997, 97, 3133-3159; R.
Oda, Molecular Gels: Materials with Self-assembled Fibrillar Networks,
R. G. Weiss and P. Terech, ed.; Springer, Berlin, 2006, 577-612; J-P.
Desvergne, A. G. L. Olive, N. M. Sangeetha, J. Reichwangen, H. Hopf
and A. D. Guerzo, Pure Appl. Chem., 2006, 78, 2333–2339; G. Clavier,
M. Mistry, F. Fages and J-L. Pozzo, Tetrahedron Lett., 1999, 40, 9021–
9024.
9 J.-S. Hu, Y.-G. Guo, H.-P. Liang, L.-J. Wan and L. Jiang, J. Am. Chem.
Soc., 2005, 127, 17090–17095.
10 V. Huber, M. Lysetska and F. Wurthner, Small, 2007, 3, 1007–1014;
T. Kishida, N. Fujita, O. Hirata and S. Shinkai, Org. Biomol. Chem.,
2006, 4, 1902–1909; T. S. Balaban, Acc. Chem. Res., 2005, 38, 612–623.
11 M. Nappa and J. S. Valentine, J. Am. Chem. Soc., 1978, 100, 5075–5080;
G. Szintay and A. Horva´th, Inorg. Chim. Acta, 2000, 310, 175–182.
12 V. F. Slagt, P. C. J. Kamer, P. W. N. M. van Leeuwen and J. N. H.
Reek, J. Am. Chem. Soc., 2004, 126, 1526–1536; P. N. Taylor and H. L.
Anderson, J. Am. Chem. Soc., 1999, 121, 11538–11545.
13 N. Yamada, K. Ariga, M. Naito, K. Matsubara and E. Koyama, J. Am.
Chem. Soc., 1998, 120, 12192–12199; M. Suzuki, C. Setoguchi, H. Shirai
and K. Hanabusa, Chem.–Eur. J., 2007, 13, 8193–8200.
1350 | Org. Biomol. Chem., 2010, 8, 1344–1350
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