close

Вход

Забыли?

вход по аккаунту

?

Graphical Abstract Angew. Chem. Int. Ed. 142006

код для вставкиСкачать
Contents
The following Communications have been judged by at least two referees to be “very
important papers” and will be published online at www.angewandte.org soon:
G. Dolphin, P. Dumy,* J. Garcia*
Control of Amyloid b-Peptide Protofibril Formation by a Designed
Template Assembly
A. Kaminaga, V. Vanag, I. Epstein*
A Reaction-Diffusion Memory Device
V. Stamenkovic, B. S. Moon, K. J. Mayrhofer, P. Ross, N. Markovic,
J. Rossmeisl, J. Greeley, J. Nørskov*
Changing the Activity of Electrocatalysts for Oxygen Reduction
by Tuning the Surface Electronic Structure
J. Blumberger,* B. Ensing, M. Klein
Formamide Hydrolysis in Alkaline Aqueous Solution: Insights
from Ab Initio Metadynamics Calculations
J. M. B. v. Colbe, W. Schmidt,* M. Felderhoff, B. Bogdanovic,
F. Sch.th*
Hydrogen Isotope Scrambling on Doped Sodium Alanate
W. Zhao, Y. Gao, S. Kandadai, M. Brook,* Y. Li*
DNA Polymerization on Gold Nanoparticles through Rolling
Circle Amplification: Towards Scaffolds for Three-Dimensional
Periodical Nanoassemblies
News
Chemoinformatics:
Prize to J. Gasteiger
2164
Organometallic Chemistry:
J. F. Hartwig Honored
2164
Biochemistry:
P. G. Schultz Awarded
2164
Books
Handbook of C-H Transformations
Gerald Dyker
reviewed by A. M. Echavarren
2165
Organisilicon Chemistry VI
Norbert Auner, Johann Weis
reviewed by G. Linti
2166
Highlights
Light at the end of the tunnel. The reports
on organocatalytic photoreactions that
are also enantioselective are few and far
between. Recently published work now
highlights a breakthrough. When special
catalysts derived from Kemp’s triacid were
used, selectivities of up to 70 % ee were
achieved (see scheme; PET = photoinduced electron transfer).
Photochemistry
P. Wessig*
2168 – 2171
Organocatalytic Enantioselective
Photoreactions
Asymmetric Synthesis
G. K. S. Prakash,* P. Beier
2172 – 2174
Construction of Asymmetric Fluorinated
Carbon Centers
2152
Various choices: Recent advances in the
construction of asymmetric fluorinated
carbon centers are discussed. Special
attention is called to catalytic enantioselective reactions such as electrophilic
fluorination (top) and decarboxylative
allylation (bottom) of fluorinated substrates.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Angewandte
Chemie
Reviews
Organometallic Catalysis
C. Bruneau,* P. H. Dixneuf* 2176 – 2203
Versatile key intermediate metal vinylidenes and allenylidenes participate in
numerous catalytic processes such as
alkene metathesis, coupling reactions,
and anti-Markovnikov additions to
alkynes. The formation of a metal vinylidene intermediate in a catalytic reaction
(see scheme) was first reported 20 years
ago, and much development in the field
has since taken place.
Metal Vinylidenes and Allenylidenes in
Catalysis: Applications in AntiMarkovnikov Additions to Terminal
Alkynes and Alkene Metathesis
Communications
Nanostructures
F. A. Aldaye, H. F. Sleiman* 2204 – 2209
Six of one and half a dozen of the other: A
cyclic hexamer of six gold nanoparticles
was sequentially and selectively selfassembled by labeling each particle (red
sphere) with a DNA-containing molecule
(colored block), which serves to dictate its
ultimate location within the final construct. This method may be used to
construct any discrete well-defined pattern of nanoparticles.
Heterogeneous Catalysis
Controlled catalysis: The combination of
magnetically and gravimetrically recoverable catalysts such as the nanoparticlebound base (see picture; blue) and the
resin-bound acid (green), respectively,
allow the application of non-complementary catalysts to multistep, one-pot reaction cascades (e.g. A!B!C). The catalysts are recovered after reaction and
reused in subsequent, unrelated reactions.
For the USA and Canada:
ANGEWANDTE CHEMIE International
Edition (ISSN 1433-7851) is published weekly
by Wiley-VCH PO Box 191161, D 69451 Weinheim, Germany. Air freight and mailing in the
USA by Publications Expediting Inc. 200
Meacham Ave., Elmont, NY 11003. Periodicals
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Sequential Self-Assembly of a DNA
Hexagon as a Template for the
Organization of Gold Nanoparticles
N. T. S. Phan, C. S. Gill, J. V. Nguyen,
Z. J. Zhang, C. W. Jones*
2209 – 2212
Expanding the Utility of One-Pot
Multistep Reaction Networks through
Compartmentation and Recovery of the
Catalyst
postage paid at Jamaica NY 11431. US POSTMASTER: send address changes to Angewandte
Chemie, Wiley-VCH, 111 River Street, Hoboken,
NJ 07030. Annual subscription price for institutions: US$ 5685/5168 (valid for print and
electronic / print or electronic delivery); for
individuals who are personal members of a
national chemical society prices are available
on request. Postage and handling charges
included. All prices are subject to local VAT/
sales tax.
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
2153
Angewandte
Chemie
Membrane Protein Imaging
Do not touch! The surface of a living cell is
soft and responsive and therefore highresolution imaging of the cell membrane
has not been possible to date. Now
noncontact imaging of protein complexes
in the plasma membrane of living cells
has been demonstrated (see picture) and
has been used to follow the cells’ structural reorganization. This breakthrough
opens up a wealth of new experiments in
membrane and cell biology.
A. I. Shevchuk, G. I. Frolenkov, D. SHnchez,
P. S. James, N. Freedman, M. J. Lab,
R. Jones, D. Klenerman,*
Y. E. Korchev*
2212 – 2216
Imaging Proteins in Membranes of Living
Cells by High-Resolution Scanning Ion
Conductance Microscopy
Host–Guest Systems
Sheer magnetism: The phase transitions
and magnetic behavior of included oxygen
in a single crystal were studied at low
temperature. The system exhibits three
correlated structural and magnetic
phases. The distinct middle-temperature
phase shows a one-dimensional-chain
arrangement of oxygen trimers with an
anomalous magnetization response to
external magnetic fields.
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
S. Takamizawa,* E. Nakata,
T. Akatsuka
2216 – 2221
Magnetic Behavior of a 1D MolecularOxygen System Included within a
Transformable Single-Crystal Adsorbent
Hold on tight: Pyrene-labeled poly(dimethylaminoethyl methacrylate) (PyrPDMAEMA) was synthesized as a multidentate ligand for CdSe nanocrystals
(NCs, see picture). The mean number of
polymers that bind to each NC can be
determined by a quantitative analytical
method based on size-exclusion chromatography. Spectroscopic characterization
of the eluted particles shows that PyrPDMAEMA binds tightly to these NCs.
Nanocrystals
In charge: Label-free DNA sequencing can
be performed by using a field-effect transistor to detect the intrinsic molecular
charges (see picture). Oligonucleotide
probes are immobilized on the Si3N4 gate
surface, and complementary target DNA
is hybridized with them. The change in
charge density on the Si3N4/SiO2 gate
caused by each single-base extension can
be measured as a shift in the threshold
voltage. VG = gate voltage.
DNA Sequencing
M. Wang, T. E. Dykstra, X. Lou,
M. R. Salvador, G. D. Scholes,*
M. A. Winnik*
2221 – 2224
Colloidal CdSe Nanocrystals Passivated
by a Dye-Labeled Multidentate Polymer:
Quantitative Analysis by Size-Exclusion
Chromatography
T. Sakata, Y. Miyahara*
2225 – 2228
DNA Sequencing Based on Intrinsic
Molecular Charges
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
2155
Contents
Gene Function
S. B. Cambridge,* D. Geissler, S. Keller,
B. CLrten
2229 – 2231
A Caged Doxycycline Analogue for
Photoactivated Gene Expression
High potential: High-resolution transgene
expression in two biological applications
demonstrates the potential of a photoactivated gene-expression technique.
Irradiation of one half of a transgenic
tobacco leaf produced a sharp boundary
of reporter gene expression between
photoactivated tissue and nonirradiated
tissue (see picture). This method was
established by synthesis of a photosensitive doxycycline analogue.
Block Copolymers
L. Yu, H. Zhang, J. Ding*
2232 – 2235
A Subtle End-Group Effect on
Macroscopic Physical Gelation of Triblock
Copolymer Aqueous Solutions
In the end: Alkyl end groups can induce a
thermoreversible sol–gel transition in an
otherwise sol-like suspension by affecting
the macroscopic self-assembly behavior.
The picture shows PLGA-PEG-PLGA tri-
Asymmetric Rearrangement
A. Nakazaki, T. Nakai,
K. Tomooka*
2235 – 2238
Asymmetric Retro-[1,4] Brook
Rearrangement and Its Stereochemical
Course at Silicon
DNA Detection
Y. Weizmann, Z. Cheglakov, V. Pavlov,
I. Willner*
2238 – 2242
Autonomous Fueled Mechanical
Replication of Nucleic Acid Templates for
the Amplified Optical Detection of DNA
2156
www.angewandte.org
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
block copolymer/water mixtures in the sol
(polymer a), gel (polymers b and c), and
precipitation states (polymer d). PLGA =
poly(lactic acid-co-glycolic acid), PEG =
poly(ethylene glycol).
Taking the silyl group a step further: An
unprecedented rearrangement in an anion
derived from an allyloxysilane occurs by a
[1,4] shift of the silyl group (see scheme).
The asymmetric synthesis of enantiomerically enriched g-functionalized allylsilanes with Si stereocenters can be
accomplished with this retro-[1,4] Brook
rearrangement. E = electrophile.
Fuel for a DNA machine: A FokI enzyme/
DNA scission machine is triggered by the
hybridization of its DNA hairpin structure
with a target nucleic acid. The machine is
fueled by a secondary fluorophore (F)- and
quencher (Q)-functionalized nucleic acid
2. Scission of 3 leads to replication of the
machinery cutter 1 and yields a fluorescent product 6, which provides an optical
output for the machine (see scheme).
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Angewandte
Chemie
Homolytic aromatic substitution reactions are used for the efficient regioselective synthesis of helicenes, phenanthrenes, and azahelicenes. The use of halo
and alkoxy substituents to control the
stereochemical outcome of this approach
and X-ray studies of the resulting helicenes are described (see structure; red O,
gray C).
Polyaromatic Compounds
Aluminum siding: Reduction of Ar’AlI2
(Ar’ = 2,6-Dipp2C6H3, Dipp = 2,6-iPr2C6H3)
in the presence of Me3SiCCSiMe3 afforded
(Ar’Al)2(CSiMe3)2 (see picture), a dialuminum-substituted cyclobutene analogue. The central four-membered Al2C2 ring
adopts a folded geometry and is isoelectronic with aromatic cyclobutadiene
dications.
Four-Membered Rings
D. C. Harrowven,* I. L. Guy,
L. Nanson
2242 – 2245
Efficient Phenanthrene, Helicene, and
Azahelicene Syntheses
C. Cui,* X. Li, C. Wang, J. Zhang, J. Cheng,
X. Zhu
2245 – 2247
Isolation of a 1,2-Dialuminacyclobutene
How low can you go? Polybenzoxazines
can display surface free energies which are
even lower than that of pure poly(tetrafluoroethylene). The contact angles and
surface free energies were monitored
during the polymerizations (see graph for
an example). These materials are cheaper
to prepare and easier to process than
fluoropolymers.
Wettability
C.-F. Wang, Y.-C. Su, S.-W. Kuo,
C.-F. Huang, Y.-C. Sheen,
F.-C. Chang*
2248 – 2251
Low-Surface-Free-Energy Materials Based
on Polybenzoxazines
A cauliflowerlike surface (see picture,
scale bar: 8 mm) and perfluorocarbon
chains on the polymer backbone result in
super water and oil repellency of a film of
the fluorinated polythiophene shown that
was electrochemically deposited on an
indium tin oxide surface. The inset shows
a camera image of a water droplet on the
surface (contact angle > 1508).
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Polymer Films
M. Nicolas, F. Guittard,
S. GPribaldi*
2251 – 2254
Synthesis of Stable Super Water- and OilRepellent Polythiophene Films
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
2157
Contents
Asymmetric Synthesis
M. Terada,* K. Machioka,
K. Sorimachi
2254 – 2257
High Substrate/Catalyst Organocatalysis
by a Chiral Brønsted Acid for an
Enantioselective Aza-Ene-Type Reaction
Lowering the load: A very small amount of
a binaphthol-derived monophosphoric
acid organocatalyst accelerates an azaene-type reaction of N-benzoylimines with
enecarbamates to provide b-aminoimines
High-Spin Systems
K. Sugisaki, K. Toyota,* K. Sato, D. Shiomi,
T. Takui*
2257 – 2260
Ab Initio MO Analysis of the Excited
Electronic States of High-Spin Quintet
2-Methylphenylene-1,3-dinitrene
with high enantiomeric purity. This catalysis with a high substrate/catalyst(S/C)
ratio provides a practical route to 1,3diamine derivatives of synthetic and biological importance.
The concept of orbital correlations
between the benzene skeleton and the
nitrene moieties of 2-methylphenylene1,3-dinitrene was used to interpret the
energy levels and characters of the excited
electronic states of this typical high-spin
quintet molecule by high-level ab initio
MO calculations. Thus, the UV/Vis
absorption spectrum of this dinitrene was
assigned theoretically for the first time
(see stick spectrum in the picture).
Asymmetric Hydrogenation
S.-M. Lu, Y.-Q. Wang, X.-W. Han,
Y.-G. Zhou*
2260 – 2263
Asymmetric Hydrogenation of Quinolines
and Isoquinolines Activated by
Chloroformates
Polymerization
H. Li, A. Debuigne, R. JProme,*
P. Lecomte
2264 – 2267
Synthesis of Macrocyclic Poly(e-caprolactone) by Intramolecular Cross-Linking
of Unsaturated End Groups of Chains
Precyclic by the Initiation
2158
www.angewandte.org
Active ingredient: Optically active tetrahydroquinolines and tetrahydroisoquinolines can be obtained by the asymmetric
hydrogenation of quinolines and isoquinolines with chloroformates as the acti-
vating reagent (e.g., ClCO2Bn, see
scheme). The method has been applied to
the asymmetric synthesis of several naturally occurring alkaloids. Bn = benzyl.
Biodegradable cyclic polyesters are synthesized by using an e-caprolactone polymerization initiated by a cyclic tin alkoxide, followed by the addition and sequential polymerization of a few units of a-(1acryloxyethyl)-e-caprolactone. Tadpoleshaped polyesters with two tails of controllable length are readily prepared by
this procedure (see picture).
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Angewandte
Chemie
Nanobiotechnology
Collagen treatment: Gold nanoparticles
conjugated with collagen mimetic peptide
(CMP) form stable adducts with collagen
fibers (see picture) that are visible by
transmission electron microscopy,
thereby allowing the study of binding
interactions between CMPs and type I
collagen fibers. This labeling technique
may potentially be used to identify structural abnormalities in collagen fibers that
are related to diseases.
X. Mo, Y. An, C.-S. Yun,
S. M. Yu*
2267 – 2270
Nanoparticle-Assisted Visualization of
Binding Interactions between Collagen
Mimetic Peptide and Collagen Fibers
CC Coupling
Y. Nakao, J. Satoh, E. Shirakawa,*
T. Hiyama*
2271 – 2274
Out with the CO: The highly regio- and
stereoselective aryl-, alkenyl-, and alkylstannylation of alkynes was achieved by
the decarbonylative carbostannylation of
propargyl 2-furoates in the presence of
Pd/C. Various functionalized alkenylstannanes were obtained that contain nucleophilic alkenylstannane and electrophilic
allyl furoate moieties, which can be
transformed by coupling reactions.
Regio- and Stereoselective
Decarbonylative Carbostannylation of
Alkynes Catalyzed by Pd/C
Domino Reactions
H. Miyamoto, Y. Okawa, A. Nakazaki,
S. Kobayashi*
2274 – 2277
An efficient and convenient approach to
the synthesis of spirocyclic oxindoles from
iodoindoles involves a sequential intramolecular CO Ullmann coupling reac-
tion and Claisen rearrangement (see
scheme). The one-pot procedure affords
3-spiro-2-oxindoles in good yield with
excellent diastereoselectivities.
Donations accepted: The reaction of
[{LAl[(SLi)2(thf)2]}2] (L = HC(CMeNAr)2,
Ar = 2,6-iPr2C6H3) with GeCl2·dioxane
yields the novel GeII !GeII-containing
hetero-trimetallic [L2Al2Ge4Li2S7] cluster,
which has a crablike structure (Al gray,
Ge magenta, Li orange, S yellow, O green,
N blue, C light gray). This cluster is the
first aluminum-containing hetero-trimetallic sulfide.
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Highly Diastereoselective One-Pot
Synthesis of Spirocyclic Oxindoles
through Intramolecular Ullmann Coupling
and Claisen Rearrangement
Cluster Compounds
Z. Yang, X. Ma, R. B. Oswald,
H. W. Roesky,* C. Cui, H.-G. Schmidt,
M. Noltemeyer
2277 – 2280
An Unprecedented Example of a Heterotrimetallic Main-Group [L2Al2Ge4Li2S7]
Cluster Containing a GeIIGeII Donor–
Acceptor Bond
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
2159
Contents
Immunoassays
Resistance movement: A submicrometer
conical pore was used for the singleaggregate detection and characterization
of immune complexes consisting of proteins such as staphylococcal enterotoxin B and antibodies. The developed assay
is rapid, label-free, requires no immobilization or modification of the antibody or
antigen, and can be performed with antibodies or proteins in serum.
J. D. Uram, K. Ke, A. J. Hunt,
M. Mayer*
2281 – 2285
Label-Free Affinity Assays by Rapid
Detection of Immune Complexes in
Submicrometer Pores
Heterogeneous Catalysis
W. Deng, M. FlytzaniStephanopoulos*
A small amount of gaseous oxygen (air)
added to the feed gas stabilizes nanostructured Au–ceria and Pt–ceria catalysts
for the water–gas shift (WGS) reaction in
H2-rich gases and start/stop operation.
Au–ceria materials emerge as practical
alternatives to expensive Pt-based catalysts for total CO removal from reformate
gas mixtures for fuel-cell use. PROX =
preferential oxidation of CO.
2285 – 2289
On the Issue of the Deactivation of
Au–Ceria and Pt–Ceria Water–Gas Shift
Catalysts in Practical Fuel-Cell
Applications
Synthetic Methods
C.-G. Dong, Q.-S. Hu*
2289 – 2292
Annulative Tandem Reactions Based on
Pd0/tBu3P-Catalyzed Cross-Coupling and
C(sp3)H Bond Activation
All together now: Pd0/tBu3P-catalyzed
annulative tandem reactions of 1,2-dihalobenzenes were carried out with hindered
Grignard reagents. This new type of
tandem reaction is believed to occur
through cross-coupling followed by cycli-
zation with C(sp3)H bond activation as
the key step and allows one-step access to
potentially useful substituted fluorenes in
high yield from readily available 1,2dibromobenzenes and 1-bromo-2-iodobenzene.
Remarkably stable—even with a hydrogen
atom at the low-coordinate phosphorus
center! A straightforward synthesis provides the thermally robust phosphasilenes
(E)/(Z)-1, which have a terminal PH
group. These compounds can be cleanly
metalated with dimethylzinc in the presence of tmeda (tetramethylethylenediamine) to afford exclusively the P-zinciosubstituted phosphasilene 2 with E configuration. R = 2,4,6-triisopropylphenyl.
Si=P Species
M. Driess,* S. Block, M. Brym,
M. T. Gamer
2293 – 2296
Synthesis of a “Half”-Parent
Phosphasilene R2Si=PH and Its
Metalation to the Corresponding
P-Zinciophosphasilene [R2Si=PM]
2160
www.angewandte.org
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Angewandte
Chemie
Biosynthesis
S. C. Wenzel, P. Meiser, T. M. Binz,
T. Mahmud, R. MLller*
2296 – 2301
Big effects from small changes: In a
comparative analysis of the nonribosomal
peptide synthetases (NRPSs) from the
biosynthetic pathways of two highly related myxobacterial lipopeptides, module
skipping and point mutations are directly
correlated to structural variations in these
natural products. The skipping process
during myxochromide S biosynthesis was
characterized biochemically and represents the first example of a module
skipping in NRPS systems.
Nonribosomal Peptide Biosynthesis:
Point Mutations and Module Skipping
Lead to Chemical Diversity
A 16-membered ring consisting of eight
aluminum or gallium atoms and eight
phosphorus atoms is the central structural motif in the polycyclic compounds
formed through the reaction of the
diphosphanyldisiloxane O(SiiPr2PH2)2
with MEt3 (M = Al, Ga; see the
heteroatom framework of the gallium
compound).
Main Group Element Compounds
Just two oxidation states are involved in
the homogeneous reduction of azo compounds at a single palladium catalyst site.
The reaction proceeds through an intermediate state in which the catalyst displays a novel palladadiaziridine structure,
and ethanol or related alcohols can be
employed as the terminal reducing agent
(see scheme).
Homogeneous Catalysis
C. von HYnisch,* S. Stahl
2302 – 2305
Synthesis of Macrocyclic Aluminum–
Phosphorus and Gallium–Phosphorus
Compounds
K. MuZiz,* M. Nieger
2305 – 2308
Catalytic Activation of NN Multiple
Bonds: A Homogeneous Palladium
Catalyst for Mechanistically
Unprecedented Reduction of Azo
Compounds
Service
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Keywords
2310
Authors
2311
Preview
2313
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
2161
Contents
Corrigenda
*
Reaction Progress Kinetic Analysis: A
Powerful Methodology for Mechanistic
Studies of Complex Catalytic Reactions
Reference [29] should read as listed below. The author apologizes for this oversight.
[29] T. Schultz, PhD Thesis, Universitt Basel (Switzerland), 2004.
D. G. Blackmond*
4302–4320
Angew. Chem. Int. Ed. 2005, 44
DOI 10.1002/anie.200462544
Diagnostics of Single Base-Mismatch
DNA Hybridization on Gold
Nanoparticles by Using the HyperRayleigh Scattering Technique
P. C. Ray*
1151–1154
The TEM image in Figure 4 showing aggregated gold nanoparticles after the addition of
target DNA into the probe DNA was not the data recorded in the study but instead an
image reported by Sato et al. (see Reference [1m]) which was used for comparative
purposes. The correct image of the sample from the study is shown below (Figure 4).
The author apologizes for this oversight and emphasizes that the error does not affect
the discussion of the results in the Communication.
Angew. Chem. Int. Ed. 2006, 45
DOI 10.1002/anie.200503114
Figure 4. TEM image of aggregated gold nanoparticles after the addition
of target DNA into the probe DNA.
[1] m) K. Sato, K. Hosokawa, M. Maeda, J. Am. Chem. Soc. 2003, 125, 8102.
For more information on
ChemMedChem see
www.chemmedchem.org
2162
www.angewandte.org
2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2006, 45, 2152 – 2162
Документ
Категория
Без категории
Просмотров
2
Размер файла
1 521 Кб
Теги
abstract, 142006, int, angel, chem, graphical
1/--страниц
Пожаловаться на содержимое документа