bluuebunny/crossref_metadata_2025 huggingface dataset:
Post-fire Germination of Hakea sericea and Petrophile sessilis after Spring Burning
Authors: York Juliet , Whelan Robert J.
Published: August 2004

Land managers are concerned about the season in which fire might be used as amanagement tool, in many ecosystems, yet there are few studies from whichresponses of plant populations might be predicted. Previous studies have beenmostly conducted in highly seasonal, Mediterranean-climate regions and thereis generally little replication of fires within a particular season. Findingsfrom these studies may be of limited value in ecosystems with weakly seasonalor non-seasonal climates, such as in the Sydney region. In this study, firebehaviour was quantified in three replicate fires in Hawkesbury Sandstonevegetation near Wollongong, New South Wales. Fires were conducted in spring1995, and seed germination of two Proteaceae species(Petrophile sessilis Sieber ex Schult. & Schult.f.and Hakea sericea Schrader) was followed for a yearafter fire. Fire intensity and patchiness varied substantially among the threesites, even though the fires occurred within a 2-week period, and the plantcommunities and fuel loads were similar. The timing of germination also varieda great deal among sites, occurring almost immediately after the fire at onesite but being delayed by nearly half a year at the other two. The amount ofgermination (but not the time course of germination) differed between thespecies: up to 70% of Hakea seeds had germinatedby week 44, whereas only around 5% of Petrophileseeds had germinated. There was also a variation in germination, especially ofPetrophile, within each site. It is concluded that, inthe Sydney region, the season of burning may not have a great impact on timingand amount of germination because rainfall is not strongly seasonal. Variationbetween sites and among years may therefore exceed variation between seasonsof burning.
Synthesis of Diastereoisomeric 1,2,3-Triphenylindans
Authors: Alesso Elba N. , Finkielsztein Liliana M. , Lantaño Beatriz , Bianchi Daniel E. , Iglesias Graciela Y. Moltrasio , Aguirre Jose M.
Published: August 2004

The stereoisomers of 1,2,3-triphenylindans were synthesized via
1,2,3-triphenylindan-1-ols. The configurational assignments of all the
compounds were made by chemical and spectroscopic methods. An unexpected
compound was isolated as a by-product of the Grignard reactions and was
identified as r-2-hydroxy-2,
t-3-diphenylindan-1-one.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXV Synthesis, Spectroscopy and Structural Systematics of Some 1 : 3 Adducts of Copper(I) Compounds with Triphenylarsine, [(Ph3As)3CuX], X = Cl, Br, I, ONO2
Authors: Hart Robert D. , Bowmaker Graham A. , Silva Eban N. de , Skelton Brian W. , White Allan H.
Published: August 2004

Crystallization of some copper(I) salts, CuX, with triphenylarsine in 1 : 3
stoichiometry from acetonitrile has yielded an array of adducts,
[(Ph3As)3CuX],
characterized by room-temperature single crystal X-ray structure
determinations.
[(Ph3As)3CuCl] (1) has
been characterized in two unsolvated phases, α and β, the second
form previously recorded as monoclinic,
P21/n,
Z = 8. The ‘α’ phase, like the
bromide (2) and iodide (3), adopts the trigonal P3
array, widespread among many
[(Ph3E)3MX] adducts with
a ≈ 19, c ≈ 11 Å;
conventional R on F was
0·037, 0·041, 0·056 for No 3458,
3259, 3434 independent ‘observed’ (I > 3σ(I)) reflections
for these three adducts respectively. A further form, γ, is a toluene
hemisolvate, monoclinic,
P21/c,
a 21·490(5), b
10·218(7), c 24·901(6) Å, β
117·53(2)°, Z = 4,
R 0·057 for No 7207. The
nitrate (4), obtained as a monosolvate from methanol, is monoclinic,
P21/n,
a 15 ·115(9), b
23·201(9), c 14·170(14) Å, β
92·56(7)°, Z = 4,
R 0·049 for No 5476. In all
compounds, the copper atom is four-coordinate, E3CuX,
the nitrate in (4) being -ONO2 unidentate. The CuX bond
lengthsr(CuX) in
[(Ph3E)3CuX] (X =
Cl, Br, I) show a decrease from the Ph3P to the
corre3sponding Ph3As compound, and this is consistent
with the observed increase in the v(CuX) wavenumbers in
the far-infrared spectra. These trends are both consistent with an increase in
the CuX bond strength from the Ph3P to the
Ph3As complexes, and possible reasons for this are
discussed.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXVII Synthesis, Spectroscopy and Structural Systematics of Some 1 : 3 Adducts of Silver(I) Compounds with Triphenylarsine, [(Ph3As)3AgX], X = Cl, Br, I, SCN
Authors: Bowmaker Graham A. , Effendy  , Kildea John D. , White Allan H.
Published: August 2004

The syntheses and room-temperature single-crystal X-ray structure
determination of 1 : 3 adducts formed between silver(I) (pseudo-)halides, AgX,
and triphenylarsine, AsPh3, are described (X =
Cl, Br, I, SCN),
[(Ph3As)3AgX],
(1)–(4). The chloride (1) has been previously described as its acetone
hemisolvate; other solvates (1a–d) (0·75 MeCN, MeOH, 1·5
pyridine, 0·75 2,6-dimethylpyridine) are isomorphous, being triclinic,
P-1, a ≈
13·5, b ≈ 14·0, c
≈ 14·25 Å, α ≈ 83, β ≈ 87, γ ≈ 76°,
V ≈ 2600 Å3,
Z = 2 f.u. The bromide (2), iodide (3) and
thiocyanate (4) are isomorphous with
[(Ph3P)3AgI],
monoclinic,
P21/n,
a ≈ 19·1, b ≈
14·0, c ≈ 17·7 Å, β ≈
97°, Z = 4 f.u. In the chlorides, Ag–Cl
are 2·494(5)–2·525(6) Å, with appreciably different
Cl–Ag–As ranges (99·7(1)–114·3(1)° in the
acetonitrile solvate; 104·8(2)–110·2(1)° in the
2,6-dimethylpyridine solvate) and more compact As–Ag–As
distributions (overall range: 109·93(8)–113·26(3)°).
For the bromide and iodide, Ag–X are 2·627(1) and 2·779(1)
Å respectively, while for the thiocyanate Ag–S is 2·550(5)
Å with Ag–S–C 104·2(3)°; the latter complexes
also display wide ranges for many of the associated bonding parameters about
the silver atom. The far-infrared spectra of
[(Ph3As)3AgX] (X
= Cl, Br, I) show v(AgX) bands at 217, 145 and
124 cm-1 respectively. The relationship between the
v(AgX) wavenumbers and the Ag–X bond length
r (AgX) is found to be the same as that for a range of
AgX complexes with phosphine ligands, and is similar to that observed
previously for analogous CuX complexes.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXX Synthesis, Spectroscopy and Structural Systematics of 1 : 2 Binuclear Adducts of Copper(I) Halides with Triphenylstibine, [(Ph3Sb)2Cu(-X)2Cu(SbPh3)2], X = Cl, Br, I
Authors: Hart Robert D. , Bowmaker Graham A. , Silva Eban N. de , Skelton Brian W. , White Allan H.
Published: August 2004

Crystallization of 1 : 2 mixtures of the copper(I) halides CuX, X = Cl,
Br, I, with triphenylstibine from acetonitrile yields adducts of 1 : 2
CuX/SbPh3 stoichiometry, confirmed by single-crystal
X-ray structure determinations. The three complexes are isomorphous,
monoclinic, P
21/c, a
≈ 24·3, b ≈ 14·2,
c ≈ 20 Å, β 110°,
Z = 4 dimers; conventional
R on F were 0·047,
0·044 and 0·045 for No 11247, 4673 and
10418 independent ‘observe’ (I > 3σ(I)) reflections
respectively. The complexes, also isomorphous with some related species, e.g.
1 : 2 AgBr,I/AsPh3, are dimers:
[(Ph3Sb)2Cu(µ-X)2Cu(SbPh3)2].
The chloride is also recorded as a chloroform disolvate, isomorphous with its
arsine analogue, being monoclinic, C
2/c, a 21·486(9),
b 17· 925(9), c
19·972(7) Å, β 91·31(3)°, Z
= 4 dimers, R 0·057 for
No 3756. The far-infrared spectra of
[(Ph3Sb)2Cu(µ-X)2Cu(SbPh3)2]
(X = Br, I) showed no clear v(CuX) bands, in
contrast to the situation reported previously for the corresponding
Ph3As compounds. A possible
v(CuCl) band is observed in the X = Cl complex at
219 cm-1 , but this occurs in a region where there is
also significant absorption in the other two compounds. The absence of strong
v(CuX) bands in these complexes is consistent with the
situation observed previously for the 3 : 1 compounds
[(Ph3Sb)3CuX].
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXXII Synthesis, Spectroscopy and Structural Systematics of Some 1 : 2 Binuclear Complexes of Silver(I) Halides with Triphenylstibine, [(Ph3Sb)2Ag(μ-X)2Ag(SbPh3)2], X = Cl, Br, I
Authors: Bowmaker Graham A. , Effendy  , Silva Eban N. de , White Allan H.
Published: August 2004

Syntheses and room-temperature single-crystal X-ray structural
characterization of binuclear 1 : 2 adducts formed between silver(I) halides,
AgX (X = Cl, Br, I), and triphenylstibine, SbPh3,
are described. The three complexes are isomorphous, being triclinic,
P-1, a ≈
18·5, b ≈ 14·6, c
≈ 14·5 Å, α ≈ 62·5, β ≈ 74, γ ≈
77°, Z = 2 centrosymmetric dimers.
Conventional R on F were
0·043, 0·038 and 0·046 for 4984, 8479 and 4166
independent, ‘observed’ (I > 3σ(I)) reflections
respectively. In
[(Ph3b)2Ag(µ-X)2Ag(SbPh3)2],
Ag–Sb range between 2·702(1) and 2·744(2) Å,
lengthening slightly from chloride to iodide; Ag–X are
2·567(5)–2·628(4) (Cl),
2·684(1)–2·737(1) (Br) and
2·826(3)–2·869(3) Å (I). The far-infrared spectra of
[(Ph3Sb)2Ag(µ-X)2Ag(SbPh3)2]
show v(AgX) bands at 178, 158 (X = Cl), 121 (X
= Br) and 110 cm-1 (X = I). The splittings
and band widths reflect a decrease in the degree of distortion of the
Ag(µ-X)2Ag units from a symmetrically bridged
structure from X = Cl to I.
Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXXIII Synthesis, Spectroscopy and Structural Systematics of New 1 : 1 'Cubane' Tetramers of Copper(I) and Silver(I) Halides with Triphenylarsine
Authors: Bowmaker Graham A. , Effendy  , Hart Robert D. , Kildea John D. , White Allan H.
Published: August 2004

Syntheses and room-temperature single-crystal X-ray structural characterization of a number of 1 : 1 ‘cube tetramer’ adducts of copper(I) and silver(I) halides, MX, with triphenylarsine, AsPh3, are recorded, being [XM(AsPh3)]4. The CuBr adduct, obtained unsolvated from toluene, orthorhombic Pbcn, a 17·844(5), b 20·778(8), c 18·430(4) Å, Z = 4 tetramers, conventional R on |F| 0·058 for No 1309 independent ‘observed’ reflctions (I > 3σ(I)), is isomorphous with previously recorded [ClAg(PPh3)]4, the tetramer having crystallographically imposed 2 symmetry. The CuI adduct, previously recorded as a monobenzene solvate, has been isolated unsolvated from toluene, monoclinic, P 21/n, a 19·70(5), b 27·110(7), c 13·59(2) Å, β 98·84(9)°, Z = 4 tetramers, R 0·087 for No 4359, isomorphous with previously recorded [ICu(PPh3)]4, as a 6½ benzene solvate, triclinic, P-1 a 26·688(2), b 15·180(7), c 13·090(1) Å, α 85·41(2), β 87·580(7), γ 77·63(2)°, Z = 2 tetramers, R 0·049 for No 11485, and as a chloroform disolvate, triclinic, P-1 a 22·584(9), b 13·979(2), c 13·892(2) Å, α 68 ·99(2), β 77·31(3), γ 75·65(3)°, Z = 2, R 0·041 for No 8701. An unsolvated AgI complex, monoclinic, P 21/c, a 25·26(1), b 12·506(5), c 25·228(9) Å, β 113·54(4)°, Z = 4 tetramers, R 0·054 for No 5520, isomorphous with previously recorded [IAg(PPh3)]4 (denoted ‘α’), was obtained from methanol/saturated potassium iodide solution, while a second ‘β’-form obtained from 2,4,6-trimethylpyridine, rhombohedral R3c, a 17·048(7) Å, α 61·15(5)°, Z = 2 tetramers, R 0·037 for No 1622, is isomorphous with previously recorded [BrAg(PPh3)]4, for which a redetermination is described (R 0·039 for No 1289); the latter has also been obtained in the common orthorhombic Pbcnarray: a 18·10(1), b 2·08(1), c 18·39(1) Å, Z = 4, R 0·041 for No 2877. A new ‘step’ form of [IAg(PPh3)]4, monoclinic, C 2/c, a 26·14(2), b 16·340(9), c 18·64(2) Å, β 114·04(8)°, R 0·058 for No 2107, obtained from acetonitrile and isomorphous with [BrCu(PPh3)]4 (step), is also recorded. In the far-infrared spectra of [(Ph3As)4Cu4X4] bands which have been assigned to vibrations of the Cu4X4 core are: 166, 150, 135, 114 (X = Br); 136, 85 cm-1 (X = I; 2CHCl3 solvate). The 166, 150, 135 cm-1 bands in the bromide are only partially resolved. These, and the 136 cm-1 band in the iodide are assigned to the T2 v(CuX) mode of the Cu4X4 core; the bands at 114 and 85 cm-1 are assigned to the next highest frequency T2 mode of the cluster. The splitting of the highest frequency T2 band for the bromide is consistent with the greater degree of distortion of the Cu4X4core from ideal Td symmetry in this complex relative to the iodide.
Synthesis and Crystal Structural Characterization of Mixed-Ligand Cadmium(II) Complexes of 3-Triphenylphosphoniopropanoate and N ,N ,N′ ,N′-Tetramethylethylenediamine (tmen)
Authors: Li Song-Lin , Mak Thomas C. W.
Published: August 2004

Two mixed-ligand cadmium(II) complexes have been synthesized from the reaction
of 3-triphenyl- phosphoniopropanoate,
Ph3P+
(CH2)2CO2¯,
and
Me2N(CH2)2NMe2
(abbreviated as tmen) with
Cd(ClO4)2.x
H2O and CdI2, and structurally
characterized by single-crystal X-ray analysis: [Cd {
Ph3P(CH2)2CO2
} 2(tmen)(H2O)]
(ClO4)2.2H2O
(1), space group P -1 with
a 13·461(5), b
13·694(5), c 18·229(4) Å, α
92·34(2), β 110·51(2), γ 117·44(2)° and
Z 2; [CdI2 {
Ph3P(CH2)2CO2
} (tmen)] (2), space group P
21/c with a 16·768(6),
b 11·741(3), c
16·915(5) Å, β 112·28(2)° and
Z 4. In complex (1), the cadmium(II) atom is in a
distorted pentagonal bipyramidal environment with two chelated betaine ligands
and one nitrogen atom of the chelated tmen ligand defining the equatorial
plane, and an aqua ligand and the other tmen nitrogen atom occupying the axial
positions. One of the betaine ligands acts in the symmetric and the other in
the asymmetric chelate mode. In complex (2), the distorted octahedral
coordination environment about the cadmium(II) atom involves a chelated tmen
ligand, an asymmetrically chelated betaine ligand, and two cis-related iodo
ligands.
The Synthesis of Some Epoxyalkyl Deoxyhalo-β-cellobiosides
Authors: Best Wayne M. , Stick Robert V. , Tilbrook D. Matthew G.
Published: August 2004

2,3-Epoxypropyl and 3,4-epoxybutyl
6′-deoxy-6′-iodo-β-cellobioside, together with 3,4-epoxybutyl
6′- deoxy-6′-fluoro-β-cellobioside, were prepared as putative
inhibitors and reporter groups for events occurring at the active site of some
β-glucan hydrolases. As well, related syntheses gave the previously
unknown 6-deoxy-6-fluoro- and 6′-deoxy-6′-fluoro-cellobioses.
A General and Diastereoselective Approach to the Preparation of cis-2,6-Disubstituted Pyrans
Authors: Varelis Peter , Johnson Brian L.
Published: August 2004

The utility of preparing cis-2,6-disubstituted
5,6-dihydro-2H-pyrans by the methodology implied in
Scheme 1 is demonstrated through the preparation of the two pyrans (1) and
(2). The overall yields for the two nine-step sequences starting from the
enals (3) and (4) were 57 and 54%, respectively, whilst the overall
diastereochemical yield approached 100%. The key features of the method
are (i) a highly regioselective Lewis acid-catalysed cyclocondensation
reaction of a nucleophilic diene with an aldehyde to afford a
2,3-dihydro-4H-pyran-4-one, (ii) reduction of a pyranone
with better than 98% regio- and stereo-chemical control to give the
corresponding glycal, and (iii) an ester enolate Claisen rearrangement of a
glycal acetate.
A Neutral Donor-Acceptor p-Stack: Solid-State Structures of 1 : 1 Pyromellitic Diimide-Dialkoxynaphthalene Cocrystals
Authors: Carlini Rina , Fang Cheng-Lin , Herrington Deborah , Higgs Kerianne , Rodrigo Russell , Taylor Nicholas
Published: August 2004

Substituted ortho-benzoquinones, generated
in situ by hypervalent iodine oxidation of catechols,
are intercepted by unsymmetrical dienes to provide Diels-Alder adducts with
complete regiospecificity. Catechols with carboxy substituents in the 3 or 4
positions react similarly and the initial adducts decarboxylate to produce
8-substituted or 5-substituted 1,2-dihydroxydihydronaphthalenes respectively,
in a one-pot three-step sequence. The reaction has been further adapted to
produce naphtho[1,8-bc]furans in a one-pot
process; its application towards the synthesis of the tricyclic system of the
sesquiterpene nardonoxide is described
Regiospecificity in the Hydroborationof 6-Hydroxyandrost-4-enes.
Authors: Hanson James R. , Hitchcock Peter B. , Liman Mansur D.
Published: August 2004

The hydroboration of 6α- and 6β-hydroxyandrost-4-en-17-one is shown
to take place predominantly on the face of the
alkenetrans to the allylic hydroxy group. The
regiochemistry of the reaction is also modified with the formation of some
5β,6α,17β-trihydroxy-5β-androstane from
6α-hydroxyandrost-4-en-17-one. The structure of this tertiary alcohol
was established by X-ray crystallography.
Synthetic, Structural and Vibrational Spectroscopic Studies in Bismuth(III) Halide/N,N′-Aromatic Bidentate Base Systems. IV. Bismuth(III) Halide/N,N′-Bidentate Ligand (1 : 1) Systems
Authors: Davis Brian R. , Hinds Mark G.
Published: August 2004

The generation of a number of 1,2-diarylcyclopropane-1,2-diols is reported.
Reaction of these in situ with acid gives, primarily, an
α,β-unsaturated ketone in which the aryl substituent attached to the
double bond is that which is best able to stabilize a benzylic cation. It is
proposed that the reaction proceeds by O-protonation of
the cyclopropane-1,2-diol, followed by loss of water and opening of the
resulting cyclopropyl cation and final deprotonation. Such initial
O-protonation contrasts with the
C-protonation normally observed in the acidolysis of
cyclopropanols and other dialkyl- and alkylaryl-cyclopropane-1,2-diols.
Four New Flavan-4-ol Glycosides from Pneumatopteris pennigera
Authors: Tanaka Nobutoshi , Ushioda Toshiyuki , Fuchino Hiroyuki , Braggins John E.
Published: August 2004

From the fronds of Pneumatopteris pennigera, four new
flavan-4-ol glycosides, named pneu- matopterins A, B, C and D, were isolated.
Their structures were determined as
(2S,4R)-5,7-di-β-D-glucopyranosyloxy-6-hydroxymethyl-8-methylflavan-4-ol,
(2S,4R)-5,7-di-β-D-glucopyranosyloxy-6,8-dimethylflavan-4-ol,
(2S,4R)-5-β-D-glucopyranosyloxy-7-hydroxy-6-hydroxymethyl-8-methyl-4,2′′-oxo-flavan,
and
(2S,4R)-5-β-D-glucopyranosyloxy-7-hydroxy-6,8-dimethyl-4,2′′-oxo-flavan,
respectively, on the basis of spectroscopic data and chemical correlations.
New Chlorinated Metabolites from the Tropical Marine Sponge Dysidea herbacea
Authors: Dumdei Eric J. , Simpson Jamie S. , Garson Mary J. , Byriel Karl A. , Kennard Colin H. L.
Published: August 2004

Three new chlorinated metabolites, namely
3-(3,3-dichloro-2-methylpropyl)-6-(3,3-dichloro-2-methyl-propylidene)-1,4-dimethylpiperazine-2,5-dione
(3),
1-methyl-3-(3,3,3-trichloro-2-methylpropyl)-6-(3,3,3-richloro-2-methylpropylidene)piperazine-2,5-dione
(4) and
5,5-dichloro-4-methyl-2-[methyl(4,4-dichloro-3-methyl-1-oxobutyl)amino]-N-(thiazol-2-ylmethyl)pentanamide
(8), have been isolated from collections of
Dysidea herbacea from the southern region of the Great
Barrier Reef. The relative and absolute stereochemistry of (4) was determined
by X-ray crystallographic analysis.
Synthesis and Structure of (17-Hydroxy-4,4,9,9,11- pentamethyl-5,8,12,13,15-pentaazaheptadec- 11-en-2-one hydrazone)nickel(II) Perchlorate; a Compound with a Hexadentate gem-Diamine Ligand
Authors: Curtis Neil F. , Gladkikh Olga P.
Published: August 2004

(4,4,9,9-Tetramethyl-5,8-diazadodecane-2,11-dione dihydrazone)nickel(II)
perchlorate reacts with 2- aminoethanol and methanal to form blue-violet
(17-hydroxy-4,4,9,9,11-pentamethyl-5,8,12,13,15- pentaazaheptadec-11-en-2-one
hydrazone)nickel(II) perchlorate. The structure of a methanol solvate was
determined
[C18H43Cl2N7NiO10,
Mr 647·2, triclinic, space
group P -1,
a 8·992(7), b
10·86(2), c 15·02(1) Å, α
79·95(2), β 76·85(5), γ 78·83(2)°,
Z 2, R 0·0637 for 2992
reflections]. The ligand has one terminal hydrazone function of the
starting material linked to the 2-aminoethanol residue by a
gem-diamine function derived from methanal. The ligand
is hexadentate, with the triplet ground state nickel(II) ion in octahedral
coordination by three secondary amine and two hydrazone nitrogen atoms and a
hydroxy oxygen atom, with the terminal hydrazone nitrogen and the hydroxy
oxygen atoms coordinated trans.
Imidazo[1,2-b]pyridazines. XXI. Syntheses of some 3-Acylaminomethyl-6-(chloro and iodo)- 2-(substituted phenyl)-imidazo[1,2-b]pyridazines and -imidazo[1,2-a]pyridines and their Interaction with Central and Mitochondrial Benzodiazepine
Authors: Barlin Gordon B. , Davies Les P. , Harrison Peter W.
Published: August 2004

A series of 3-acylaminomethyl-6-(chloro, iodo and methyl)-2-(phenyl,
4′-t-butylphenyl, 4′-cyclohexyl- phenyl, biphenyl-4′-yl,
4′-chlorophenyl and
4′-iodophenyl)imidazo[1,2-b]pyridazines
and imidazo[1,2- a]pyridines has been prepared
and examined for interaction with central and mitochondrial (peripheral- type)
benzodiazepine receptors. The
imidazo[1,2-b]pyridazines were generally more
selective for the mitochondrial receptors than the corresponding
imidazo[1,2-a]pyridines. Of these compounds,
3-
acetamidomethyl-2-(biphenyl-4′-yl)-6-chloroimidazo[1,2-b]pyridazine
(9) proved to be the most selective in studies of the displacement of
[3H]diazepam from peripheral-type and central
benzodiazepine receptors (IC50 2·8 nM and
0% displacement at 1000 nM, respectively).
Synthesis and Chlorination of Chloromethyl Methylsulfonylmethyl Sulfide
Authors: Ahern Terence Patrick , Hennigar Tracy L. , MacDonald Justin Anthony , Morrison Heather Grace , Langler Richard Francis , Satyanarayana Satyendra , Zaworotko Michael J.
Published: August 2004

A new cleavage reaction establishes rational access to the title compound.
Treatment of the title compound with molecular chlorine establishes that
methylsulfonyl is better than chloro as a directing group in the chlorination
of unsymmetrical sulfides
Potential GABAB Receptor Antagonists. VIII. The Synthesis of 3-Amino-N-aryl-2-hydroxy- propane-1-sulfonamides and Analogues of Baclofen Containing Nitro Groups
Authors: Hughes Robert , Prager Rolf H.
Published: August 2004

3-Amino-N-aryl-2-hydroxypropane-1-sulfonamides were
synthesized by the reaction of the corresponding epoxy sulfonamide with sodium
azide, followed by reduction to the corresponding amine. The synthesis of
3-nitropropan-1-amine and two 2-thienyl derivatives is also reported.
3-Amino-2-hydroxy-N-(4-nitrophenyl)propane-1-sulfonamide
and 3-nitropropan-1-amine were found to be specific antagonists of GABA at the
GABAB receptor. Substitution of the amino group by alkyl
or aryl groups reduced the activity.
β-Acarbose. I The Synthesis of 1-Epivalienamine
Authors: McAuliffe Joseph C. , Stick Robert V.
Published: August 2004

Improvements and modifications to a literature procedure for the synthesis of
multigram amounts of a derivative of 1-epivalienamine are described. As well,
various other derivatives of 1-epivalienamine, of potential use in the
synthesis of carba sugars, are reported.
β-Acarbose. III. The Attempted Alkylation of a 1-Epivalienamine Derivative with Various Carbohydrate Triflates
Authors: McAuliffe Joseph C. , Stick Robert V.
Published: August 2004

Various carbohydrate triflates have been treated with cyclohexylamine and a
1-epivalienamine derivative to give some of the desired secondary amine, but
mainly the product of a competing elimination reaction, namely a mixture of
alkenes. When the reactions were conducted in the presence of potassium
carbonate, novel carbohydrate carbamates were formed.
β-Acarbose. V. The Synthesis of a Hydroxylated Derivative of a Diastereoisomer of Methyl Acarviosin
Authors: McAuliffe Joseph C. , Stick Robert V.
Published: August 2004

The treatment of a 1-epivalienamine derivative with
1,6:3,4-dianhydro-2-O-benzyl-β-D-galactose has given
an amino alcohol capable of conversion into either a cyclic carbamate or an
aziridine. All attempts at acetolysis of the 1,6-anhydro ring of the cyclic
carbamate failed owing to the inherent reactivity of the (allylic) benzyl
ethers present in the molecule. Therefore, following a reduction with lithium
in ammonia and acetylation of the product, a new cyclic carbamate was obtained
which underwent successful acetolysis to provide a heptaacetate. This
heptaacetate could be transformed into the desired methyl β-D-glucoside
and base hydrolysis provided the 6-hydroxylated derivative of a
diastereoisomer of methyl acarviosin, a putative inhibitor of enzymes which
process β-D-glucosidic linkages.
β-Acarbose. VI The Synthesis of a Hydroxylated Derivative of a Diastereoisomer of Acarbose
Authors: McAuliffe Joseph C. , Stick Robert V.
Published: August 2004

A glycosyl bromide derived from an Nlinked carba
disaccharide has been converted into a phenyl thioglycoside and condensed with
benzyl
2,3,6,2′,3′,6′-hexa-O-benzyl-β-cellobioside
to give an N-linked carba tetrasaccharide. Complete
removal of protecting groups then gave the 6′′-hydroxylated
derivative of β-acarbose, coined ‘β-adiposin-2’, a
putative inhibitor of enzymes that process β-D-glucosidic linkages.
Semiclassical Quantum Mechanics, Bond Delocalization and the Mills - Nixon Effect
Authors: Miller Ian J.
Published: August 2004

Conjugated π electrons in a ring system are described in terms of a
transverse wave propagated along the carbon skeleton. Kekule benzene is
forbidden because the π electron quantal wave self-interferes. The
characteristics of an aromatic system are expressed in terms of the weighted
combination of Kekule structures, and resonance energy occurs through
combining canonical structures with conservation of momentum. The resonance
energy of benzene is calculated as 1·045 times the energy difference
between two carbon-carbon single bonds and one double bond, or 162 kJ/mol
on one bond energy scheme. Bond localization is due to differences in wave
impedance between zones represented by adjacent phase space cells; wave
reinforcement occurs in one zone, cancellation in another as a consequence of
the directional asymmetry of phase changes of the quantal wave. Quantal wave
impedance can be altered by altering the localized potential, and it is
proposed that the so-called Mills-Nixon effect arising from the annelation of
bicyclic rings occurs because the bicyclic ring better focuses a polarization
field. The polarization field arising as a consequence of strain is shown to
semiquantitatively account for the bond alternation. The difference between
exo and endo bond lengths in tris(bicyclo[2.1.1]hexeno)benzene is
calculated to be 7·2 pm, compared with 9 pm as determined
experimentally.
Synthesis and Anti-Acetylcholinesterase Activity of Some 5-Substituted 1-Methyl-1H-1,2,4-triazol-3-yl Methanesulfonates
Authors: Holan George , Virgona Christopher , Watson Keith G.
Published: August 2004

5-Chloro-1-methyl-1,2-dihydro-3H-1,2,4-triazol-3-one
(12) and
N-isopropyl-2-methyl-5-oxo-2,5-dihydro-1H1,2,4triazole3-sulfonamide
(14) have been prepared from 1-methyl-5-thioxo-1,2,4-triazolidin-3-one (7) and
converted into the methanesulfonate esters (15) and (16). The
anti-acetylcholinesterase and insecticidal activities of (15) and (16) have
been compared with those of the known
5-isobutylthio-1-methyl-1H-1,2,4-triazol-3-yl
methanesulfontate (4).
Synthesis of Stentorin.
Authors: Cameron Donald W. , Riches Andrew G.
Published: August 2004

The two isomeric structures (2) and (3) proposed for the photodynamic pigment
stentorin have both been synthesized for the first time, thereby allowing
unambiguous identification of the natural material as (2). Synthesis of these
highly condensed aromatic systems involved controlled oxidative couplings of
the new anthrones (7) and (8), each synthesized by regiocontrolled
cycloaddition.
The Constituents of Marine Sponges. VIII Minor Diterpenoid Metabolites of Aplysilla rosea and A. var. sulphurea
Authors: Taylor Walter C. , Toth Stephen
Published: August 2004

Extraction of a further sample of the encrusting
spongeAplysilla rosea Barrois yielded 11 new
diterpenoids, aplyroseol-8 to -18, in addition to previously isolated
compounds. The structures were determined by spectroscopic studies and by
chemical conversions in some cases. A sample of A. var.
sulphureagave 15,16-diacetoxyspongian and
16-oxospongian.
A Versatile Synthesis of Linked Cyclodextrins
Authors: Easton Christopher J. , Eyk Steven J. van , Lincoln Stephen F. , May Bruce L. , Papageorgiou John , Williams Michael L.
Published: August 2004

Reactions of amino-substituted cyclodextrins with bis(3-nitrophenyl) oxalate,
malonate, succinate and glutarate, and with diphenyl carbonate, afford a range
of linked cyclodextrins. These include α- and β-cyclodextrin dimers,
joined by substitution at either C6 or C3, and asymmetric species with a
β-cyclodextrin bonded to an a-cyclodextrin and a C3-substituted
cyclodextrin attached to a C6-substituted moiety.
Synthesis of Further b-Ketoalkyl Lichen Depsides
Authors: Elix John A. , Wardlaw Judith H.
Published: August 2004

The unambiguous total synthesis of the lichen depsides
2-O-methylglomelliferic acid (39),
4-O- methylhyperolivetoric acid (40), hyperconfluentic
acid (41), microphyllinic acid (42), arthoniaic acid (43),
2′-O-methylmicrophyllinic acid (44),
2′-O-methylhyperphyllinic acid B (45),
4-O-methylsuperolivetoric acid (46),
2′-O-methylhyperphyllinic acid A (47),
2′-O-methylnorsuperphyllinic acid (48) and
4-O- methyloxocryptochlorophaeic acid (49) has been
achieved by the condensation of an appropriately substituted orsellinic acid
and protected phenol in the key step, followed by deprotection.
Crystal Structures of (3S*,4S*,5S*,6S*)-3,4-Epoxy- 1,7-dioxaspiro[5.5]undecan-5-ol, (3R*,5S*,6S*)-1,7- Dioxaspiro[5.5]undecane-3,5-diyl Diacetate and (4S*,5S*,6S*)-1,7-Dioxaspiro[5.5]undecane-4,5-diol
Authors: Brimble Margaret A. , Johnston Andrew , Hambley Trevor W. , Turner Peter
Published: August 2004

The structures of
(3S*,4S*,5S*,6S*)-3,4-epoxy-1,7-dioxaspiro[5.5]undecan-5-ol
(2),
(3R*,5S*,6S*)-1,7-
dioxaspiro[5.5]undecane-3,5-diyl diacetate (4) and
(4S*,5S*,6S*)-1,7-dioxaspiro[5.5]undecane-4,5-diol
(5) have been determined by X-ray crystallography. The unsubstituted
tetrahydropyran ring in (2) adopts an axial position with respect to the
epoxy-substituted ring and the hydroxy group at C5 is
syn to the epoxide group. Intermolecular hydrogen
bonding is observed between the C5 hydroxy group and O1. The two six-membered
rings in (4) adopt chair conformations and the two acetate groups adopt
1,3-diaxial positions. The C5 hydroxy group in (5) assumes an axial position
anti to the C-O bond of the neighbouring ring whilst
4-OH occupies an equatorial position. Intermolecular hydrogen bonding is also
observed between 4-OH and 5-OH. Compound (2),
C9H14O4, M
186·21, crystallized in the monoclinic space group
P 21/c
with a 7·867(1), b
12·2060(9), c 9·3676(8) Å, b
102·744(8), V 877·4(1) Å
3 and No
1163 [I > 2·5s
(I)], R 0·031,
Rw 0·035. Compound (4),
C13H20O6,
M 272·30, crystallized in the triclinic space
group P 1 with a 9·902(1),
b 11·0024(9), c
6·9183(5)Å, a 104·078(8), b 96·769(9), g
101·980(8), V 703·8(1) Å
3 , No 1657
[I > 2·5s(I)],
R 0·047, Rw 0·044.
Compound (5),
C9H16O4,
M 188·22, crystallized in the orthorhombic space
group Pbca with a
25·504(3), b 8·909(2),
c 8·038(2) Å, V
1826·4(5) QA 3 , No 1096
[I > 2·5s(I)], R 0·030,
Rw 0·030.
Synthesis and Characterization of Chiral Conducting Polymers Based on Polypyrrole
Authors: Chen Fang , Akhtar Parveen , Kane-Maguire Leon A. P. , Wallace Gordon G.
Published: August 2004

A range of optically active pyrrole monomers have been synthesized in which a
chiral sub- stituent is covalently bonded either to the pyrrole N or C3 ring
position, namely
(–)-(1R)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide,
(+)-(1S)-4-methyl-N-(1-phenylethyl)pyrrole-3-carboxamide,
(–)-(1R)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide,
(+)-(1S)-4-methyl-N-(1-naphthylethyl)pyrrole-3-carboxamide,
(+)-(2S)-2-(1H-pyrrol-1-yl)propionic
acid,
(+)-(1S)-N-(1-phenyl-ethyl)pyrrole,
and
(–)-(1R)-N-(1-phenylethyl)pyrrole.
Their chiroptical properties have been established by circular dichroism
spectroscopy. Electropolymerization of the three
N-substituted pyrrole monomers provided films of chiral
conducting polymers, whose electrical and spectroscopic properties are
described. Although oxidation of the C3 substituted pyrrole monomers was also
facile, electrodeposition was poor and films of the associated polymers could
not be obtained.
Structure, Electronic Spectrum and Angular-Overlap Bonding Parameters of Bis[bis(pyrazol-1-yl)(2-thienyl)-methane](nitrato-O,O′)nickel(II) Nitrate
Authors: Astley Timothy , Hitchman Michael A. , Skelton Brian W. , White Allan H.
Published: August 2004

The crystal structure of the complex
[Ni(pz2thCH)2(O(O′)NO′′)]
NO3 has been determined by X-ray diffraction, where pz
and th represent the pyrazolyl and thienyl groups of a potentially tripodal
ligand. The thienyl groups are not bound to the metal, which is coordinated to
four pyrazolyl groups and a chelating nitrate ion. The electronic
‘d–d’ transition energies are interpreted in terms of
angular-overlap bonding parameters which agree well with those reported for
other similar complexes.
Complexes of Naproxen and Ibuprofen with 6A-Amino-6A-deoxy-b-cyclodextrin
Authors: Ashnagar Alamdar , Culnane P. Tin , Easton Christopher J. , Harper Jason B. , Lincoln Stephen F.
Published: August 2004

At pD 6·80 in D2O containing 0·10 mol
dm-3 phosphate buffer, the association constants of the
complexes of Naproxen and Ibuprofen with
6A-amino-6A-deoxy-β-cyclodextrin
are 810±200 and 8900±2100 mol-1
dm3 , respectively, while those of the corresponding
complexes with β-cyclodextrin are 940±170 and 8800±1800
mol-1 dm3 , respectively. A
2D-ROESY experiment shows that Naproxen includes lengthwise in the substituted
cyclodextrin, with the reverse orientation to that of the complex with
β-cyclodextrin. The orientation in the host{guest complex of the
substituted cyclodextrin results in the alignment of the host amino
substituent and the guest carboxy group, which at this pD are predominantly
protonated and deprotonated, respectively. The similarity in the association
constants of the complexes of Naproxen indicates that any stabilization
provided by interactions between the ionic groups in the complex of the
substituted cyclodextrin is offset by other factors, such as the extent of
desolvation of the host and guest.
Cyclopropa-Fused Quinones. The Generation and Trapping of Bicyclo[4.1.0]hepta-1(6),3-diene-2,5-dione and 1H-Cyclopropa[b]naphthalene-2,7-dione
Authors: Collis Gavin E. , Jayatilaka Dylan , Wege Dieter
Published: August 2004

The title compounds (3) and (4) have been generated at low temperature by
debromosilylation of
1-bromo-6-trimethylsilylbicyclo[4.1.0]hept-3-ene-2,5-dione (23) and
1a-bromo-7a-trimethylsilyl-1a,7a-dihydro-1H-cyclopropa[b]naphthalene-2,7-dione
(38) respectively. Both cyclopropa-fused quinones are reactive but each could
be trapped with furan to give a pair of cycloadducts, which were remarkably
resistant to cycloreversion. In the absence of added trapping agent, the
cyclopropanaphthoquinone (4) was intercepted by fluoride ion to give
1a-fluoro-1a,7a-dihydro-1H-cyclopropa[b]naphthalene-2,7-dione
(39) in low yield. These findings indicate that the quinones (3) and (4) do
not behave like cycloproparenes but still possess much of the reactivity
inherent in the strained bicyclo[4.1.0]hept-1(6)-ene system (32).
Theoretical calculations at the Becke3LYP/6-31G* level have been
carried out on (3) and the isomeric structures
bicyclo[4.1.0]hepta-1,5-diene-3,4-dione (1) and
bicyclo[4.1.0]hepta-1(6),4-diene-2,3-dione (2); these reveal that
(2) and (3) lie 78·7 and 58·6 kJ/mol respectively above (1).
The Selective Activation of Telluro- over Seleno-β-D-glucopyranosides as Glycosyl Donors: a Reactivity Scale for Various Telluro, Seleno and Thio Sugars
Authors: Stick Robert V. , Tilbrook D. Matthew G. , Williams Spencer J.
Published: August 2004

Phenyl
tetra-O-benzoyl-1-telluro-β-D-glucopyranoside, when
treated with
1,2:3,4-di-O-isopropylidene-α-D-galactose in the
presence of N-iodosuccinimide and
trifluoromethanesulfonic acid, immediately forms the expected
β-disaccharide derivative. A subsequent experiment involving both a
telluroglycoside and a selenoglycoside as donors with the one alcohol acceptor
showed complete preference for the telluroglycoside. This result has led to an
extension of the investigation to establish a ‘reactivity scale’
for various telluro, seleno and thio sugars.
Crystal and Molecular Structures of Ru3(CO)12-n(PMe3)n n = 1, 2)
Authors: Bruce Michael I. , Skelton Brian W. , White Allan H. , Zaitseva Natasha N.
Published: August 2004

The crystal and molecular structures of the title compounds are described.
Both contain a triangular Ru3 core [average Ru-Ru
2·853 (n = 1),
2·837 Å (n =
2)], with the PMe3 ligands occupying equatorial
positions. For n = 2, substantial twisting about
the Ru-Ru bonds results in one CO group adopting a semibridging position
across the Ru-Ru vector joining a substituted Ru with the
Ru(CO)4 fragment. Comparisons are also made with the
previously determined n = 3 complex.
Structural and Electrochemical Studies of Some Cobalt(III) Complexes of 2-Aminomethylbenzimidazole and 2-(N-Methylaminomethyl)benzimidazole
Authors: Cardwell Terence J. , Edwards Alison J. , Hartshorn Richard M. , Holmes Rodney J. , McFadyen W. David
Published: August 2004

A number of mixed-ligand cobalt(III) complexes containing either the ligand
2-aminomethylbenzimidazole (ambi) or its N-methyl
derivative, namely 2-(N-methylaminomethyl)benzimidazole (mambi), have been
prepared in relatively low yield; in particular, the complexes
[Co(ambi)(acac)2] Cl,
[Co(ambi)(Clacac)2] Cl,
K[Co(ambi)(ox)2],[Co(ambi)2(acac)]
(ClO4)2,
[Co(mambi)(acac)2] Cl and
[Co(mambi)(Clacac)2 ]Cl (acac =
acetylacetonate, Clacac = 3-chloroacetylacetonate, ox =
oxalate). The reduction potentials of these complexes have been measured in
order to assess whether molecules of this type could be potential
redox-activated hypoxic cell selective anticancer agents. The complex
[Co(ambi)(acac)2]
Cl.4·1H2O was characterized by single-crystal
X-ray crystallography: a 19·425(1),
b 17·734(1), c
15·979(1) Å, β 117·52(1)˚, monoclinic, space
group C 2/c (No.
15)
Macrocycle Formation Through Carbon Acid - Formaldehyde Condensation Reactions of Bis(propane-1,2-diamine)- and Bis(2-methylpropane-1,2-diamine)-copper(II) Ions
Authors: Rossignoli Monica , Bernhardt Paul V. , Lawrance Geoffrey A. , Maeder Marcel
Published: August 2004

The reaction of the bis(1,2-diamine)copper(II) complexes of racemic
propane-1,2-diamine (pn) and 2-methylpropane-1,2-diamine (dmen) with
formaldehyde and nitroethane in methanol under basic conditions yields minor
macrocyclic condensation products in addition to the major acyclic products.
Where C-pendant methyl groups on the pair of coordinated
diamines are in cis dispositions, the first
–NH–CH2–C(CH3)(NO2)–CH2–NH–
ring formation occurs at amine pairs distant from these
C-methyl substituents, and further reaction to yield a
macrocycle is not observed. However, where the C-methyl
substituents are in transdispositions, the chemistry
proceeds to yield the macrocycle. Commencing with pn,
trans-(6,13-diammonio-2,6,9,13-tetramethyl-1,4,7,10-tetraazacyclotetradecane)copper(II)
perchlorate formed and crystallized in the space group P
21/n, with
a9· 782(2), b
9·2794(6), c 17·017(4) Å, β
103·24(1)°. The copper ion is found in a square-planar environment,
with the two methyl groups of the pn residues and the pairs of introduced
pendant groups all in trans arrangements.
The Iodine—Thiosulfate Reaction: a Pulse-Radiolysis Study and Spectrophotometric Evidence for the Intermediates I2S2O32- and IS203-.
Authors: Packer John E. , Anderson Robert F.
Published: August 2004

Spectroscopic evidence for
I2S2O32-
and IS2O3-,
postulated as intermediates in the iodine{thiosulfate reaction, has been
obtained by using the technique of pulse radiolysis to oxidize iodide to
I3- in the presence of
thiosulfate. The spectra show blue shifts with respect to
I3- and I2
respectively. The kinetics of the reaction over a range of concentrations
different from those reported by Scheper and Margerum
have also been studied and further evidence for their quantitative scheme has
been obtained; a change predicted by their model, but not detected by them, in
kinetic order in
S2O32- at
low thiosulfate and high iodide concentrations has been found.
Acetylenic Phosphines Bridging Two Cluster Units: Molecular Structure of {Ru3(µ-H)(µ3-C2But )(CO)8}2(µ-dppa)[dppa =C2(PPh2)2]
Authors: Bruce Michael I. , Humphrey Paul A. , Skelton Brian W. , White Allan H.
Published: August 2004

The syntheses of two complexes consisting of two
Ru3(µ-H)(µ3-C2But)(CO)8
clusters bridged by acetylenic ditertiary phosphines,
C2(PR2)2
[R = Ph (3), Bun (4)], are described.
The molecular structure of (3) confirms that substitution of the cluster at
the ruthenium which is σ bonded to the acetylide has occurred. The
structural parameters closely resemble those of
Ru3(µ−H)(µ3-C2But)(CO)8(L)
[L = CO, PPh2(OEt)].
The Synthesis of Some Epoxyalkyl b-C-Glycosides as Potential Inhibitors of b-Glucan Hydrolases
Authors: Best Wayne M. , Ferro Vito , Harle Julia , Stick Robert V. , Tilbrook D. Matthew G.
Published: August 2004

The treatment of tetra-O-benzyl-D-glucono-1,5-lactone
with various alkenylmagnesium halides gave the intermediate lactols which,
upon reduction (Et3SiH/BF3)
and protecting group manipulation, yielded alkenyl
tetra-O-acetyl-β-D-C-glucopyranosides
in good yield. These β-D-C-glucosides were
precursors of the epoxyalkyl β-D-C-glucopyranosides,
themselves putative inhibitors of b-glucan hydrolases. Similar additions of
Grignard reagents to per-benzylated cellobionolactone were not as successful
in yielding epoxyalkyl β-C-cellobiosides. The
addition of Grignard reagents to
1,2-anhydro-3,4,6-tri-O-benzyl-α-D- glucose offers
a viable alternative route to the prop-2-enyl
β-D-C-glucoside, but not to the but-3-enyl and
pent-4-enyl counterparts. Likewise, the addition of Grignard reagents to a
1,2-anhydro cellobiose gave disappointing results. Preliminary results are
reported for a novel approach to alkenyl
β-D-C-glucosides by the alkylation of nitromethyl
β-D-C-glucosides.
Regioselectivity in the Lithiation of 1,3-Disubstituted Arenes
Authors: Baker Robert W. , Liu Song , Sargent Melvyn V. , Skelton Brian W. , White Allan H.
Published: August 2004

The regioselectivity of the lithiation of
1,4,5,8-tetramethoxynaphthalene-2-carbaldehyde (7) with butyllithium or
phenyllithium in the presence of
N,N,N′-trimethylethylenediamine
and the subsequent bromination of the lithiated species so generated with
1,2-dibromotetrafluoroethane were investigated. Similar investigations with
butyllithium as base in the presence of
N,N,N′,N′-tetramethylethylenediamine
or potassium t-butoxide were carried out on
1,4,5,8-tetramethoxynaphthalene-2-methanol (14). These studies were extended
to 1,5,8-trimethoxynaphthalene-3-methanol (25), 3-methoxybenzenemethanol (29)
and 3,5-dimethoxybenzenemethanol (32). The X-ray crystal structure of
6-bromo-1,4,5,8-tetramethoxynaphthalene-2-methanol (17) is described.
The Crystal Structure of Chloro(1,10-phenanthroline-2-carboxamide Oxime)copper(II) Nitrate
Authors: Childs Bradley J. , Craig Donald C. , Scudder Marcia L. , Goodwin Harold A.
Published: August 2004

In chloro(1,10-phenanthroline-2-carboxamide oxime)copper(II) nitrate thecopper atom adopts a distorted square pyramidal structure with bridging chlorogroups producing a zigzag chain in which each tridentate phenanthroline amideoxime group coordinates through the oxime nitrogen atom and is essentiallyplanar. The planes of the tridentates are almost parallel, giving a stackedarray of the ligands within the chain. The nitrate ions link chains throughhydrogen bonding with the amino and oxime hydrogen atoms of the carboxamideoxime group. The crystals are monoclinic, space group P21/c,a9·2199(6), b21·794(1), c 7·2889(4) Å, β99· 900(3)˚, Z 4.
Two New Isonakafurans from the Great Barrier Reef Sponge Dysidea sp. nov.
Authors: Flowers Andrew E. , Garson Mary J. , Byriel Karl A. , Kennard Colin H. L.
Published: August 2004

Two new sesquiterpenes, the furan
Δ7,14-isonakafuran-9 (11) and the autoxidized
derivative (12), were isolated from the sponge Dysidea
sp. nov. collected from One Tree Island on the Great Barrier Reef. The
structures of the two new sesquiterpenes, which both contain a
bicyclo[4.3.1]decane skeleton, were deduced by use of one- and
two-dimensional n.m.r. spectroscopy, in particular by n.O.e. and HMBC
experiments. Compound (11) is isomeric with nakafuran-9 (6) while the
hydroperoxide derivative (12) was subjected to X-ray crystallographic analysis
to confirm its relative stereochemistry at C1 and C11. Both metabolites have
growth inhibitory activity against the P388 cell line,
while the hydroperoxide derivative (12) is also inhibitory to the marine
fungus Trichophyton mentagrophytes.
Synthetic, Structural and Vibrational Spectroscopic Studies in Bismuth(III) Halide/N,N′-Aromatic Bidentate Base Systems. IV Bismuth(III) Halide/N,N′-Bidentate Ligand (1 : 1) Systems
Authors: Bowmaker Graham A. , Hannaway Frances M. M. , Junk Peter C. , Lee Aaron M. , Skelton Brian W. , White Allan H.
Published: August 2004

Room-temperature single-crystal X-ray studies are recorded for a number of
adducts of BiX3 and
N,N′-bidentate ligand (2,2′-bipyridine (bpy)
or 1,10-phenanthroline (phen)), devoid of coordinated solvent.
BiBr3/bpy/MeCN (1 : 1 : 1) is triclinic
P-1, a
12·129(2), b 9·955(4),
c 7·748(1) Å, α 73·14(2),
β 77·34(1), γ 69·79(2)°, Z
= 2; conventional R on
|F| was 0·036 for
No 2252 independent
‘observed’ (I >
3σ(I)) reflections. The phen analogue is
isomorphous, a 11·586(3), b
10·839(6), c 7·769(10) Å, α
73·70(7), β 76·67(7), γ 70·34(4)°,
Z = 2, R 0·042 for
No 800.
BiI3/bpy (1 : 1) is triclinic,
P-1, a
11·742(4), b 9·261(1),
c 8·261(3) Å, α 86·46(2),
β 71·48(3), γ 67·25(2)°, Z
= 2, R 0·043 for
No 1164. All complexes are
centrosymmetric binuclear
[(N,N′-bidentate)X2Bi(µ-X)2BiX2(N,N′-bidentate)]
with six-coordinate pseudo-octahedral bismuth(III). Attempts to produce a
chloride analogue have resulted, in the case of
N,N′-bidentate = bpy, in a novel adduct of
BiCl3/bpy 1 : 1·5 stoichiometry, monoclinic,
P21/c,
a 9·377(8), b
17·699(5), c 21·58(1) Å, β
107·82(6)°, Z = 8,
R 0·055 for
No 1804. The complex is
[(bpy)2Cl2Bi(µ-Cl)BiCl3(bpy)],
containing seven- and six-coordinate bismuth. Bands in the far-infrared
spectra due to the v(BiX) vibrations in
[(bpy)2Cl2Bi(µ-Cl)BiCl3(bpy)]
and
[(bpy)I2Bi(µ-I2)BiI2(bpy)]
are assigned and discussed in relation to the structures of the complexes.
p-Di-t-butoxybenzene
Authors: Carman Raymond M. , Kanizaj Nicholas , Taylor Richard J. K.
Published: August 2004

p-Di-t-butoxybenzene (1)
[p-di-tert-butoxybenzene;
benzene, 1,4-di-tert-butoxy-;
1,4-bis(1,1-dimethyl-ethoxy)benzene; 1,4-benzenediol (or benzene-1,4-diol)
di-tert-butyl ether; Chem.
Abstr. number 15360-01-7] does not have the
physical properties ascribed to it in the Dictionary of Organic Compounds,
where it has been mistaken for 2,5-di-t-butylhydroquinone (4).
Bracteatine, a Quaternary Glucoalkaloid from Ophiorrhiza bracteata
Authors: Arbain Dayar , Byrne, Lindsay T. , Dachriyanus  , Evrayoza Noversa , Sargent Melvyn V.
Published: August 2004

Extraction of the aerial parts of Ophiorrhiza bracteata
Bl. (Rubiaceae) has yielded the known quaternary indole alkaloid ophiorrhizine
(1) and the new glucoindole alkaloid bracteatine (2), the structure of which
followed from its spectroscopic properties.
Influence of Trimethylsilyl Substituents on Primary C - O Bond Lengths at the b-Position: Results from Low-Temperature X-Ray Structural Studies
Authors: Green Alison J. , Issa William , White Jonathan M.
Published: August 2004

The β-trimethylsilyl substituent in 2-trimethylsilylethyl
p-nitrobenzoate (12b) and 2-trimethylsilylethyl
2,4-dinitrobenzenesulfenate (12c) leads to significant lengthening of the
C(alkyl)–O(ester) bond. Lengthening of the Si-CH2
distance in the more electronegative ester (12c) relative to (12b) is also
observed. These structural effects are consistent with the presence of
σC-Si–σ*
C-O interactions.
Conformation of a Fluorochrome from Aniline Blue
Authors: Mackay, Maureen F. , McTigue Michael J. , Sadek Maruse
Published: August 2004

The solid-state conformation of the fluorochrome sodium
4,4′-[carbonylbis(benzene-4,1-diyl)bis(imino)]-bisbenzenesulfonate
has been defined by single-crystal X-ray crystallography. Monoclinic crystals
belong to the space group C
2/c with a 11·732(1),
b 6·185(1), c
37·179(3) Å, β 94·40(1)° and
Z 8. The structure was refined to a final
R0·042 for all 2271 unique terms. In the crystal
six oxygen atoms form an octahedral grouping around the sodium ion and these
octahedra are linked into layers sandwiched between the layers of organic
anions which adopt an extended conformation. The n.m.r. spectra indicate that
in solution the fluorochrome is flexible and averages to an extended structure
that maintains symmetry about its longitudinal and carbonyl axes. Chemical
shifts have been measured in water, deuterium oxide and
(D6)dimethyl sulfoxide