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Graphical Abstract (Angew. Chem. Int. Ed. Engl. 121994)

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A Journal of the
Gesellschaft
Deutscher Chemiker
International Edition in English
J!Q9!!&
33/12
Pages 1199- 1306
COVER PICTURE
The cover picture shows the spliceosome cycle, in which CC, A, B1, B2, C1, C2, and
I represent splice complexes within the splicing pathway that have been distinguished biochemically and/or genetically and which are formed from precursor
RNA (pre-RNA) and small nuclear ribonucleoproteins (shown in color). PremRNA enters these complexes and exits as mRNA and excised lariat RNA (left).
RNA splicing of split genes contributes to the great variety of proteins. During this
splicing process, which occurs in eukaryotic cells, “superfluous” RNA sequences
(introns) are spliced from the pre-RNAs, and the remaining RNA segments, the
exons. are joined. In this way, depending on the combination of exons, different
mRNAs and from these subsequently proteins with different functions-are
generated, which, for example, is clearly critical for the viability of many vertebrate
organisms. Phillip A. Sharp in his Nobel lecture on p. 1229ff. reports on the discovery of RNA splicing and on the splicing mechanisms.
REVIEWS
Contents
What did it feel like to invent the polymerase chain reaction? In his Nobel Lecture
K . B. Mullis gives an entertaining and philosophical account of his journey that
resulted in a powerful new method, completely automated in the meantime, for the
synthesis of as much identical DNA as desired from one single strand.
Double helices of short oligonucleotides formed the starting point for the studies of
M. Smith for the application of synthetic oligonucleotides in biochemistry. This led
to processes for isolation of genes and sequencing double-stranded DNA and to the
determination of mRNA ends, mutagenesis. and genotype selection.
Not a bend or kink in the DNA, but the flip of the
base to be methylated out the DNA helix (picture on
the right) occurs when a methyltransferase binds to
DNA. This was the key result of the X-ray structure
analysis of a ternary complex of M.HhaI, AdoMet,
and a 5-fluorocytosine-substituted DNA double
helix. This conformational shift may generally play
a major role in the opening up of DNA helices.
Atrgeu . Chiw. h r l . Ed. E t i ~ l 1994.
.
33, N o . I 2
VCH Vrrlugsgesellschujt mhH. 0-69451 Weinhrrm, I994
K. B. Mullis* .........................
1209-1213
The Polymerase Chain Reaction (Nobel
Lecture)
M. Smith* .............................
1214-1221
Synthetic DNA and Biology (Nobel
Lecture)
R. J. Roberts * ........................
1222 1228
-
An Amazing Distortion in DNA Induced
by a Methyltransferase (Nobel Lecture)
0570-0833:94i12I2-120I S 10.00
+ .25:0
1201
The discovery in 1977 that genes of eukaryotic organisms contain nonsense segments
(“introns”) earned P. A. Sharp the 1993 Nobel Prize for Medicine. The introns at the
stage of RNA are displaced by spliceosomes or in a self-splicing process (outlined
schematically below). A denotes an adenosine residue, P phosphate groups. the
rectangles R N A sequences that are joined together. and the lines the intron that is
spliced.
P. A. Sharp * ................ ......., . . 1229 - 1240
Split Genes and RNA Splicing (Nobel
Lecture)
COMMUNICATIONS
An easier, faster, cheaper approach to the enzymatic synthesis of oligosaccharides
would be to employ whole cells rather than purified enzymes. In this report recombinant E. co/i cells mediate the inannosylation of monosaccharides and glycopeptides. It was also proven that the relevant enzyme, mannosyl transferase, does not
leak from the periplasmic space of the cells into the medium.
G. F. Herrmann, P. Wang.
G.-J. Shen,
A potent inhibitor is easily accessible. The pyrrolidine derivative 1 effectively inhibits
r-galactosidase ( K , = 5 x l o - * M), since it mimics the transition state structure of the
cleavage of the glycosidic bond. Compound 1 can be prepared by chemical (see
below) and chemoenzymatic routes.
Y-F. Wang, Y Takaoka,
C.-H. Wong* .........................
1) Fuculose
I-phosphate-
0
HOJcHo
+
N3
Pd-C/H2
OH
H O A O P O g - a l d o l a s e -
1241 -1242
Recombinant Whole Cells as Catalysts for
the Enzymatic Synthesis of Oligosaccharides and Glycopeptides
1242-1244
xoH
HO
t
C.-H. Wong* ..........................
Remarkable Stereoselectivity in the Inhibition of a-Galactosidase from Coffee Bean
by a New Polyhydroxypyrrolidine Inhibitor
2) Acid phosphaw
1
Controlled hydrolysis of (mesityl),GaOH leads to
the first structurally characterized galloxane hydroxide 1, which crystallizes as [l(thf),]. 6THF.
The framework of 1 consists of a distorted Ga, octahedron whose faces are capped alternately by p 3 - 0
or p3-OH ligands. Only the ipso-C and 0 atoms of
the mesityl and four T H F substituents, respectively,
are shown in the picture on the right.
(rneaityl),Ga,O,(OH),
c
o
J. Storre, T. Belgardt, D. Stalke,
C
---p
R----
60
Benzene wins the battle for aromaticity against
[I 8lannulene. The first fully conjugated, benzenecontaining porphyrin analogue 1 is not an 18 r[: aromatic system; only the tautomer with the intact
arene is observed. This compound is synthesized
from the corresponding tripyrranedicarboxylic acid
and isophthalaldehyde and forms black-blue crystals.
1202
?‘.
VCH Ver/uggese//scha/fn h H . 0.69451 Wernhcrm,fYY4
1244-1246
Synthesis and Structure of the First
Organometallic Galloxane Hydroxide
Mes,Ga,O,(OH),
1
poi-Bridging of naphthalene by a boron atom causes
a large distortion in the sp2 bond angles at C1 and
C8 in the naphtho[l,8-bc]boret 1. The resulting ring
strain is evident in the chemistry of l : on treatment
with electron-poor boron compounds BX, an unexpected ring expansion to 2 (X = C1, Br, OEt) is observed.
H . W. Roesky* .......................
K. Berlin,
E. Breitmaier* .............______....
1246-1247
Benziporphyrin, a Benzene-Containing,
Nonaromatic Porphyrin Analogue
iPr,
N
,iPr
,Pr
I
x y -N-,/’
&&
1
2
A. Hergel, H. Pritzkow,
W. Siebert* .............................
1247-1248
Synthesis and Reactivity of a Naphtho[1,8-bc]boret
fJS70-0833!94i1212-1202 5 fO.OO+ .21W
Angebi. Chem. Inr. Ed. EngI. 1994, 33,N o . 12
To what extent can ah initio calculations he trusted? Is silacyclopropyne (1) a transition state or an energy minimum? The experimental work described here demonstrates that all four C,H,Si isomers 1-4 can exist.
G. Maier,* H . P. Reisenauer,
H. Pacl ...................................
1248-1250
C,H,Si Isomers: Generation by Pulsed
Flash Pyrolysis and Matrix-Spectroscopic
Identification
2
1
4
3
Topologically nonplanar hydrocarbons 2 and 3 are available from triptindantrione 1
in only a few steps. Threefold addition of PhLi to 1 and subsequent cyclodehydration provides 2. In contrast, threefold addition of LiCECR leads surprisingly to a
centrohexacyclic tris(eno1 ether), which can be isomerized thermally into the corresponding triketone.
1
2
t
B
u
e
G
(
CH,
HC
,
>’
CH,
p
t
t Bu
J. Sundermeyer,*
D. Runge ...............................
1255-1257
The Bonding Capability of Imido Complex
Fragments of Groups 5-7 with Regard to
the Isolobal Relationship
R
II
I
H. Viebrock, U. Behrens,
E. Weiss * ...............................
The disproportionation of dimethylmagnesium to give
novel organomagnesium ions is possible with the
tripod ligand N.N’,N”-trimethyl-l,4,7-triazacyclononane (tacn). The cation in 1 has a triple-decker
structure (shown on the right); the anion is the first
trimagnesate, whose structure is intermediate to
those of monomeric and polymeric compounds.
1257 1259
-
A Novel Organomagnesium Compound
Consisting of Two Triple-Decker Cations
[LMg(p-Me),MgL]+ and an Octamethyltrimagnesate Anion :
[{Me,Mg(P-Me),) 2 MgI2-
1
Since the free radical induced degradation of chlorinated hydrocarbons yields phosgene, the exact kinetic data for phosgene’s behavior in aqueous solution is of interest. Its hydrolysis was examined at temperatures ranging from 13 to 59 “C. Phosgene
itself was generated by radiolysis of aqueous CCI, solutions [Eq. (a)].
+%
.+I
~ C C 1 , O O1
lilt.
Base-Free Monomeric Organogallium
Hydrides ~
~
1
NR
Anyrw. C‘lwm
Synthesis of Centrohexacyclic Hydrocarbons by the Propellane Route: Centrohexaindan and Tribenzocentrohexaquinane
A. H. Cowley,* F. P. Gabba‘i,
H. S. Isom. C. J. Carrano.
1253-1255
M. R. Bond ...........................
The same number of valence orbitals and valence electrons, as well as valence orbitals
of similar symmetry and energy, results when the cyclopentadienyl ligand in
[(?7s-C,R,)M] is substituted by an imido ligand NR and the metal atom by an
isoelectronic M’ of the next higher group (see the series below). Through coupling
of the imido complex fragments with [CpFe(CO),], the characteristic bonding capability of each entity can be determined.
CC1, I”+. C C 1 3 d
1251-1253
3
Stable tricoordinate mono- and dihydrides of gallium. I and [(Ar)Ga(H),].
respectively, can be isolated by taking advantage of the kinetic stabilization afforded by bulky Ar
substituents. The monohydride 1,
prepared from [(Ar),GaCI] and LiGaH,, is the product of an unusual
rearrangement reaction. Ar = 2,4.6rBuC,H,.
[(tacn)Mg(/i-Me),Mg(tacn)l,[Mg,Me,l
D. Kuck,* B. Paisdor,
D. Gestmann .........................
+ .OH
Ed. Enyl. 1994, 33. N o . 12
CC1,OH
I‘
+
CI,C=O
+ CO,
+ 2HCI
R. Mertens, C. von Sonntag,*
J. Lind, G. Merenyi ............... 1259-1261
A Kinetic Study of the Hydrolysis of
Phosgene in Aqueous Solution by Pulse
Radio1ysis
(a)
I’CH Virlugsgusellsrhu// m b H , 0-69451 Wcinheim, lYY4
0570-0833!94!1212-1203
B 10.00+ .25:0
1203
Vinylperoxyl radicals surprisingly absorb in the visible region, whereas other peroxyl
radicals absorb in the UV. Thus the kinetics of reactions of both vinylperoxyl
radicals and vinyl radicals can be studied conveniently. The peroxyl radicals are
formed by pulse radiolysis of oxygen-containing aqueous solutions of vinyl halides
like 1 [Eq.
. (a)].
.
(a)
A change from a butterfly structure to a tetrahedral arrangementis triggered in the Al,
framework by the oxidation of 1 to 2 in toluene at 23 "C. Remarkably, only one
methyl group of 1 is oxidized; 2 is stable for several days in solution.
R. Mertens,
C. von Sonntag* ....................
1262-1264
Determination of the Kinetics of Vinyl
Radical Reactions bv the Characteristic
Visible Absorption Spectra of Vinylperoxyl
Radicals
S. J. Trepanier,
S. Wang* ...............................
1265- 1266
Oxygen-Induced Structural Transformation of the Polynuclear Organoaluminum
Complex [A1,(p3-8-quinolylimide),(CH,),] to [Al4(p,-8-quinolylimide),(CH,),(P-OCH,)I
The bicyclic cations 1 and 2 are formed in the reactions of the dimeric arsenium ions
3 and 4.respectively, with 2,3-dimethylbuta-1,3-diene.These cycloadditions can be
interpreted as Diels-Alder reactions in which the heteroatom-arsenic bond is formally considered a double bond; the analogous phosphenium ions react differently.
Counterion: GaCI, .
N. Burford,* T. M. Parks,
P. K. Bakshi,
T. S. Cameron* ......................
1267-1268
The First Cycloaddition Reactions of
Dimeric Arsenium Cations
@S-As
A two-coordinate sodium atom is present in the linear diorganosodate anion in 1,
obtained by metalation of the relevant trisilylmethane with sodium in the presence
of tmen (N,N,N',N'-tetrarnethylethylenediamine); the corresponding reaction with
tris(dimethy1phenylsilyl)methane in the absence of the chelating ligand yields 2,
which has a distorted tetrahedral environment about the sodium atom and an
unprecedented chain structure.
[Na(trnen),(Et,O)][Na{C(S~Me~)~),J
1
Na[C(SiMe,Ph),]
2
Permethylated heteroradialenes are excellent candidates for donor components in
donor-acceptor complexes because of their electronic properties. The thiaradialenes 1 and 2 and the expanded thiaradialene 3 were synthesized in an astonishingly
easy way. Results of photoelectron spectroscopy and cyclic voltammetry show that
compounds 1 and 2 are indeed electron-rich systems.
+
The surprisingintramolecular 14 21cycloaddition of a cobaltacyclopentadiene to a complexed cyclobutadiene
is the key step of the synthesis of the
superphane 1. Furthermore, novel
superphanes like 2 can be constructed from tricyclic diketones.
1204
#(-,'
G a
0
S. S. Al-Juaid, C. Eaborn,
P. B. Hitchcock,
K. Izod, M. Mallien,
J. D . Smith* ...........................
1268-1270
Metalation of Tris(trimethylsily1)- and
Tris(dimethylphenylsily1)methane with
Methylsodium : The First Dialkylsodate
R. Gleiter,* H. Rockel,
H. Irngartinger,
T. Oeser .................................
1270-2272
Efficient Synthesis of Heteroradialenes by
SN'-Reaction
R. Gleiter,* H. Langer,
B. Nuber ................................
1272- 1274
New Types of Metal-Stabilized
butadiene Superphanes
Cyclo-
co
-
1
VCH Verlu~.sgRe.~ells~iiuft
nihH. D-69451 Wrinhrnn,1994
e
2
U570-0833:'94:12/2-12U4S i<J.UU+ .2S:U
Angeiv. C'lieni. I n r . Ed. Engl. 1994, 33. No. 12
C. Duschl,* M. Liley,
H. Vogel .................................
Lion of laterally structured ihiolate films on gold
surfaces with domains of contrasting
- surface prop- erties. These monolayers with areas of amphiphilic
disulfides and others of mercaptocarboxylic acids,
each covalently bound, can be used for the selective formation of multilayers of copper thiol complexes (shown schematically on the right). The
principle of this technique can also be applied to
other fields, for example, biochemistry.
*'
/--c ~ ' .ic ~ P . c i~0~ * c ~ ~ ~ c ~ ~ +
OH O O H OOH OOH
v/ v/ v/ "
/
I
l
1274-1276
Micrometer-Scale Lateral Structuring of
Organic Layers through Self-Organization
l
Successive metalation of primary amines, first with nBuLi and then with Sb(NMe,), ,
has enabled the preparation of the heterometallic complexes 1 and 2. Neutral
[Ph(CH,),N(H)Li], and ionic Li[Sb(cyNH),] occur as the intermediates in the formation of 1 and 2, respectively.
A. J. Edwards, M. A. Paver,
P. R. Raithby, M.-A. Rennie,
C. A. Russell,
D. S. Wright* ........................
1277-1279
A New Method for the Synthesis of
Heterometallic Complexes : Syntheses and
Structures of [(PhCH,CH,NLi),Sb(thf)l,
and [Sb,(cyN),(NMe,),]Li
NAD' functions not as a redox reagent but as an electrophile in the second step in the
degradation of histidine. In this as yet unique enzymatic reaction, water is added to
urocanic acid ( l ) ,leading to the formation of 2. The proposed mechanism has now
been substantiated by NMR spectroscopic results on the I3C-labeled adduct 3.
R = ADP-ribosyl, 0 = 13C.
Hoot>
HodCOOH
K-cOOH
N v N H
C. Schubert, Y. Zhao, J.-H. Shin,
J. Retey* ................................
1279-1280
On the Mechanism of the Urocanase
Reaction: Confirmation of the Structure of
the NAD+-Inhibitor Adduct by Direct
13C-13CCoupling
CONH,
4
N-NH
N+
1
I
2
R
3
A. R. Otte, A. Wilde,
H. M. R. Hoffmann* ............ 1280-1282
A series of cis-diphenylated cyclopropanes has been
introduced into the C-H acidic position of a range of
nucleophiles, for example, deprotonated esters and
acid amides, ketones, and sulfones. In these reaccomplextions bis[ (~3-1,3-diphenylallyl)palladium]
es serve as electrophiles, and products such as 1
form. Quaternary carbon centers exocyclic to the
newly formed three-membered ring are installed
with ease.
1
A completely conjugated n system with participation of the Ru centers characterizes
the cationic complex 1 4 + , which was formed from the analogous mononuclear Ru"
complex by selective C4-C4' coupling. This is confirmed by crystallographic and
NMR spectroscopic findings as well as the fact that strong electronic communication is displayed between Ru" and Ru"' in 1 3 + .
lQC
Ailern
Chwi 1111.G I . G i g / . 1994, 33. N o . 12
sc
VCH Verla~sge.sell.sch~f/
mhH, 0-69451 Wmlwirn, 1994
Cyclopropanes by Nucleophilic Attack of
Mono- and Diaryl-Substituted (q3-Allyl)palladium Complexes: Aryl Effect and
Stereochemistry
J.-P. Sutter, D. M. Grove,
M. Beley, J. P. Collin,
N. Veldman, A. L. Spek,
J.-P. Sauvage,
G. van Koten* .......................
1282-1285
Copper(r1)-Mediated Oxidative Coupling
of Bis(dimethy1aminomethyl)arylruthenium Complexes to Give
[ (terpy)Ru"'(pincerpincer)Ru"'(terpy)](CuCI,),
0570-0833~94/1212-1205S 10.00+ .25/0
1205
Participation of the oxygen atoms of the siloxane
framework of ligand I , and not only the terminal
hydroxyl groups, may be required for the coordinative saturation of a metal center. This surprising
conclusion was drawn from the X-ray structure
analysis of the first rare earth metal complex with
this type of ligand. Compound 1 serves as a molecujar model for sio, supports for transition metal cdtalysts.
W. A. Herrmann,*
R. Anwander, V. Dufaud,
W. Scherer ..............................
1285-1286
Molecular Siloxane Complexes of Rare
Earth Metals-Model System for SilicateSupported Catalysts?
1
Five interlocked rings in a linear arrangement form
the familiar symbol of the Olympic Games and also
describe olympiadane, a [5]catenane which was assembled from eight components in two steps at ambient temperature and pressure. This self-assembly
process is possible as sufficient molecular recognition was programmed into the components. The
fragmentation patterns in the mass spectrum and
the ‘H N M R spectrum support the structure shown
schematically on the right.
m
-w
-
m -’r.
D. B. Amabilino, P. R. Ashton,
A. S. Reder, N. Spencer,
J. F. Stoddart* .......................
1286-1290
Olympiadane
+
+
One of the largest cluster complexes whose structure has been elucidated is the title
compound, which is formed from CuC1, PEt,, and P(SiMe,),, when the components
are used in the ratio 1 :0.5:0.6. The structure, which is difficult to describe, can be
discussed as an intermediate in the formation of binary Cu,P.
D. Fenske,*
W. Holstein ............................
An internal volume of approximately
1000 A3 is available in the permanent
cavity of a new rigid host molecule
(shown on the right). The holand
was assembled in six reaction steps
by the fusion of four cavities of
two calix[4]arene and two resorcin[4]arene building blocks, which
are connected by amide spacers. This
host is expected to show novel complexation properties.
P. Timmerman, W. Verboom,
F. C. J. M. van Veggel, W. P. van Hoorn,
D. N. Reinhoudt* ................. 1292-1295
With the “correct” combination of 3- and 5-substituents and the appropriate catalyst
the C = N / N - O hydrogenation of isoxazolines 1 proceeds with high stereoselectivity
to yield hydroxypyrrolidines 2 with variable side chains in one step, by two-fold
reduction and recyclization, as shown in the example in Equation (a).
R. Miiller, T. Leibold,
M. Patzel, V. Jager* .............. 1295-1298
,
&
[Cu,,P3,{P(siMe,),},(PEt,),,l,
a New
Phosphorus-Bridged Copper Cluster
An Organic Molecule with a Rigid Cavity
of Nanosize Dimensions
A New Synthesis of 1,3,4-Trideoxy-l,4iminoglycitols of Varying Chain Length by
(C, C,)-Coupling of Ally1 Halides with
Glycononitrile Oxides
+
CI
0-N
1290-1292
llZ. cat.,
OH
In many cases with high thveo selectivity, Grignard
additions can be performed on simple, nonactivated, and even enolizable imine derivatives of optically
active aldehydes, as the reactions with 1 and 2 show.
This should open a new route to aminohydroxy
acids that supplements the familiar one starting
from cc-amino acids/aldehydes.
Bnp
En0
3Bn
H OQBn
1
2
T. Franz, M . Hein, U. Veith,
V. Jager,* E.-M. Peters, K. Peters.
H. G. von Schnering .............. 1298-1301
Simple and Versatile Synthesis of Optically
Active 1,2-Amino Alcohols by Grignard
Addition to N,O-Dibenzylglyceraldimine
and -1actaldimine
*Author to whom correspondence should be addressed
1206
i : V C l i ~ ~ ~ l ~ ~ g ~ g r . s rnbH,
e l D ~0-69451
h ~ f f r Weinl?erm.1994
0570-0H33194:1212-12~~
S 10.00
+ .25!0
Arrgcmv. Clztw. 1111.Ed. Engl. 1994. 33. No. 12
BOOKS
Contents
H . Hopf ...........................................
1303
S. Hojjmunn ....................................
1303
Electrode Kinetics for Chemists, Chemical Engineers, and Materials
Scientists . E. Gileadi
W. Schmickler ..................................
1304
Dictionary of Trivial Names/Trivialnamen-Handbuch. Vols. 1-3
informationszentrum Chemie
U. Eberhurdt ................................
1305
W. Muder .........................................
1306
Chemistry Imagined. Reflections on Science
Unraveling DNA
*
R. Hoffmann, V. Torrence
M. D. Frank-Kamenetskii
*
Scanning Electron Microscopy and X-Ray Analysis
- R. E. Lee
*
Fach-
Events 1208
Preview A-64
Author Index A 4 3
No Enantioselective Reactions in a Static Magnetic Field
Based on part of the P h D thesis by G. Zadel (completed
1993) and parallel investigations by Catja Eisenbraun the
communication “Enantioselective Reactions in a Static
Magnetic Field” appeared under my auspices together with
G . Zadel. C. Eisenbraun. and G . J. Wolff in this journal
(Angcw. Chem. 1994, 106, 460; Angew. Chem. Int. Ed. Engl.
1994. 33. 454). Several independent research groups have
informed me since that the experiments reported (1 ,Zaddition of Grignard compounds to aldehydes; reduction of
prochiral ketones with lithium aluminum hydride), contrary
to the results published by us gave no enantiomeric excesses.
In light of this I instructed three experienced co-workers
from my research group (F. Keller, K. Berlin, and T. Marx)
to repeat the most’ important experiments [reduction of 2acetylnaphthalene with lithium aluminum hydride to (R)- or
(S)-l-(2-naphthyl)ethanol;1-2-addition of methylmagnesiuin iodide to benzaldehyde to give (R)-or (S)-I-phenylethanol] completely independently from the chief experimentalist (G. Zadel). These co-workers carried out several experiments in Bonn and Karlsruhe, some in my presence but all
in the absence of G. Zadel, and could detect no measureable
enantiomeric excesses (NMR with [Eu(hfc),], G C with c(-cyclodextrin, polarimetry). In one case, we were able to prove
quite clearly (GC-MS, polarimetry) that the starting solution
prepared by G . Zadel for the reduction of propiophenone
with lithium aluminum hydride also contained considerable
amounts of ( +)-I -phenylpropanol in addition to propiophenone. G. Zadel admitted this deception and two other manipulations in front of witnesses. Therefore we must assume
that the data in the publication as well as “successful” attempts at reproducing the results by other co-workers in my
research group and guest scientists in the presence of G.
Zadel came about because of consistent and particularly
cleverly disguised manipulations. I therefore wish to disassociate myself and the coauthors C. Eisenbraun and G. J. Wolff
from all the experimental results in this publication.
E. Breitmaier
Institut fur Organische Chemie und Biochemie der Universitit
Gerhard-Domagk-Strasse 1, D-53121 Bonn (FRG)
Received: June 21, 1994
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