bluuebunny/crossref_metadata_2025 huggingface dataset:
Lewis Base Adducts of Silver(I) p-Toluenesulfonate. IV. The Preparation and Crystal Structures of the Complexes of Silver(I) p-Toluenesulfonate with 2,6-Diaminopyridine, Quinolin-8-ol, Hexane-1,6-diamine, and the Adduct of Hexane-1,6-diamine
Authors: Smith Graham , Thomasson Jon H. , White Jonathan M.
Published: December 2005

The reaction of silver(I) p-toluenesulfonate{Ag(pts} with a series of nitrogen bases has provided furtherexamples of adducts including one {with 2,6-diaminopyridine (dap),[{Ag(pts)} (dap)]n (1)} whichis a variant of the known polymeric adduct type[{Ag(pts)}(L)m]n,together with a second previously unreported complex type in which the ptsligand is displaced but remains as a counter anion[Ag(L)m+].(pts-) [withquinolin-8-ol (oxine), [Ag(oxine)2+].(pts-) (2);hexane-1,6-diamine (dah),[Ag2(dah)32+]n.2n(pts-)(3)]. Compound (1) is polymeric and is based on four-coordinate distortedtetrahedral AgN2O2 centres[Ag{N, 2·249, 2·326(2) Å; Ag−O,2·491, 2 ·554(2) Å]. Compound (2) comprises discreteAgN2O2 complex units in which theuncharged oxine ligands are asymmetric bidentate [Ag−N,2·208−2·222(5) Å; Ag−O,2·563−2·597(5) Å]. Compound (3) hasthree-coordinate silver centres with the metal coordinated to two dah ligandslinearly in a polymeric chain [Ag−N, 2·186, 2·191(4)Å], with a third, longer interaction [Ag−N,2·494(4) Å] completing a T-shaped coordination. In addition,the structure of the adduct of AgClO4 withhexane-1,6-diamine{[Ag(dah)+]n·n(ClO4−)}(4) has been determined, and is polymeric, comprising classicalcentrosymmetric linear AgN2 coordination[Ag−N, 2·121(3) Å] with only weakhydrogen-bonding interactions to the perchlorate
Diastereoselectivity in the O - H Insertion Reactions of Carbenoids Derived from Phenyldiazoacetates of Chiral Alcohols. II. Comparison of Rhodium(II)- and Acid-Mediated Reactions
Authors: Miller David J. , Moody Christopher J. , Morffitt C. Neil
Published: December 2005

Rhodium(II)- or acid-mediated decomposition of 2-diazo-2-phenylacetates of
chiral alcohols in the presence of various hydroxylic compounds (ROH) results
in the diastereoselective formation of 2- hydroxy-, 2-alkoxy- or
2-trialkylsiloxy-2-phenylacetates, with the acid-mediated process giving the
higher diastereoselectivity.
Powder diffraction studies of synthetic calcium and lead apatites
Authors: Kim Jean Y. , Fenton Ronald R. , Hunter Brett A. , Kennedy Brendan J.
Published: December 2005

The crystal structures of
M10(PO4)6X2,
where M = Ca or Pb and X = OH¯, F¯, Cl¯ or
Br¯, have been determined by Rietveld refinement of powder synchrotron
X-ray and neutron diffraction data. All the compounds are hexagonal with space
group P 63/m. For the calcium
compounds, the lattice parameters are a =
9.4302(5), 9.3475(3), 9.5902(6), 9.6482(6) and c
= 6.8911(2), 6.8646(1), 6.7666(2), 6.7788(2) Å, for X =
OH¯, F¯, Cl¯, Br¯, respectively. For the lead compounds,
the corresponding lattice parameters are a =
9.8612(4), 9.7547(5), 9.9767(4), 10.0618(3) and c
= 7.4242(2), 7.2832(2), 7.3255(1), 7.3592(1) Å. In these
compounds there are two cation sites, a channel of M(I) atoms and a triangle
of M(II) atoms. The anion interacts most strongly with the M(II) atoms with
the interaction dictating the position of the anion relative to the M(II)
triangle. In
Ca10(PO4)6X2,
the F¯ ion sits within the triangle planes, while the larger OH¯ and
Cl¯ anions are disordered above and below the M(II) triangles. The even
larger Br¯ is midway between two triangles at (0, 0, ). Despite the
larger size of the isostructural lead compounds, no anions are found in the
triangles. The F¯, Cl¯ and Br¯ ions are at (0, 0, ) and the
OH¯ ion is disordered at (0, 0, z). This difference
in behaviour is possibly related to the lead 6s electrons. In this paper, the
experimental results are presented and possible reasons for the observed
differences are discussed.
Synthesis and characterization of hydrophilic hydroxy-pyridinones and their complexes with molybdenum(VI)
Authors: Epstein Noah A. , Horton Jennifer L. , Vogels Christopher M. , Taylor Nicholas J. , Westcott Stephen A.
Published: December 2005

We have prepared four N-substituted hydroxypyridinones
containing alcohol and morpholine groups. Complexes of the type
cis-MoO2L2,
where L represents the hydroxypyridinonato ligands have also been synthesized.
The ethanolamine derivative,
cis-MoO2(hep)2
(5), has been characterized by an X-ray diffraction study whereby the
pyridinone ligands are bound to molybdenum in a cis
bidentate fashion via the deprotonated hydroxy groups and the ketone moieties.
Crystals of (5) are triclinic, with a 9.1930(7),
b 14.2718(8), c 14.6219(9)
Å, α 106.816(5), β 95.902(5), γ 96.350(5)°,
Z 4, space group P–1.
Flash vacuum pyrolysis of N-alkenylbenzotriazoles and N-alkenylisoxazolones
Authors: Cox Matthew , Heidarizadeh Fariba , Prager Rolf H.
Published: December 2005

The flash vacuum pyrolysis of 1-(2-ethoxycarbonylethenyl)benzotriazole has
been reinvestigated, and the processes leading to the formation of ethyl
indole-3-carboxylate and 2-ethoxyquinolin-4(1H)-one
elucidated. Similar pathways are followed in the flash vacuum pyrolysis of the
corresponding benzisoxazolone. Some
N-ethenylisoxazolones have been pyrolysed to form
pyrroles, but rearrangement of the intermediate carbenes may be observed.
Photolysis of the isoxazolones gives carbenes that may be captured by solvent
or give pyrroles.
Structural Systematics of Rare Earth Complexes. X (‘Maximally’) Hydrated Rare Earth Acetates
Authors: Kepert Cameron J. , Wei-Min Lu , Junk Peter C. , Skelton Brian W. , White Allan H.
Published: December 2005

Extension/augmentation of preexisting work carried out in respect of room-temperature single-crystal X-ray structural characterization of trivalent rare earth acetates, crystallized as ‘maximal’ hydrates, Ln(ac)3.x H2O, from aqueous solution under local ambience, suggests the following array to be prevalent: For Ln = La(-)Pr: triclinic P 1 sesquihydrate, i.e. x = 1½, a ≈ 13·4, b ≈ 10·1, c ≈ 8·6 Å, α ≈ 75·6, β ≈ 103·8, γ ≈ 92·8°, Z = 4 mononuclear f.u., conventional R on |F| for Ln = La, Ce, here, being 0·043, 0·058 for No 3199, 4442 independent ‘observed’ (I > 3σ(I)) diffractometer reflections respectively; the complexes have the form of a two-dimensional polymer, in the ac plane, the dominant motif being a chain of lanthanoid atoms of two types linked by acetate bridges along a ... Ln(1)Ln(2)Ln(2)Ln(1)Ln(1)Ln(2) ... with further acetates cross-linking the Ln(1) in the c dimension. For Ln = (Ce(-))Nd: monoclinic P 21/c monohydrate, a ≈ 8·4, b ≈ 8·0, c ≈ 15·0 Å, β ≈ 94°, Z = 4 mononuclear f.u., for the present determinations R were 0·024, 0·044 for No 2019, 2600, the structure being a one-dimensional polymeric form with acetate bridges. For Ln = Sm(-)Lu, (i.e. implicitly with intermediate Ln): triclinic P1 tetrahydrate, a ≈ 10·4, b ≈ 9·2, c ≈ 8·8 Å, α ≈ 118, β ≈ 114, γ ≈ 92°, Z = 2 mononuclear f.u., R were 0·035, 0·030 for No 4583, 4678, the complexes being acetate-bridged dimers. It is of interest that, through the three series, the variation in the degree of hydration is not monotonic. Determinations are also recorded for a pair of crystalline compounds obtained during the attempted crystallization of europium(III) acetate hydrate from aqueous solution acidified with acetic acid (Hac), supporting their formulation as entailing the formation of mixed water/acetic acid solvates Eu(ac)3.2H2O.Hac and Eu(ac)3.H2O.2½Hac, i.e. [Eu2(ac)6(OH2)4].2Hac and [Eu2(ac)6(OH2)2(Hac)2].3Hac with common binuclear cores in which a pair of unidentate water molecule ligands in the former is replaced by a pair of unidentate acetic acid ligands in the latter with relatively minor geometrical change. The former array is rhombohedral R3, a 26·865(7), c 10·328(3) Å (hexagonal setting), Z = 9 binuclear units, isomorphous with the previously reported samarium analogue, and the latter triclinic P1, a 14·131(5), b 8·919(4), c 8·582(3) Å, α 65·41(3), β 84·72(3), γ 84·27(3)°, Z = 1 binuclear unit, R 0·046, 0·051 for No 1700, 2553. An interesting double salt, trisodium hexakis(acetato)ytterbate(III) tetrahydrate, Na3[Yb(ac)6].4H2O, is monoclinic, C2/c, a 13·139(3), b 13·936(2), c 26·030(2) Å , β 91·10(1)°, Z = 8, R 0·053 for No 3467. The eight-coordinate (YbO8) environment is comprised of oxygen atoms from a pair of O,O′-chelating and four unidentate acetate moieties.
Structural Systematics of Rare Earth Complexes. XXI Polymeric Sodium Bis(thiodiglycolato)neodymiate(III)
Authors: Kepert Cameron J. , Skelton Brian W. , White Allan H.
Published: December 2005

A single-crystal, room-temperature, X-ray structure determination is recorded
for the title compound, NaNd(tdga)2
(‘tdga2-’ ≡
−OCOCH2SCH2COO-).
Crystals are monoclinic, space group Pc,
a 9·5058(4), b
7·323(1), c 9·402(4) Å, β
97·71(2)°, Z = 2 f.u., conventional
R on |F| being
0·028 for No 1054
independent ‘observed’ (I >
3σ(I)) diffractometer reflections. The compound is
a novel polymeric array; the neodymium atom is eight-coordinated by ligand
oxygen atoms at distances ranging from 2·43(2) to 2·54(1)
Å. A redetermination of the parent thiodiglycolic acid is also recorded
(orthorhombic Pnam, a
5·0444(8), b 6·690(1),
c 17·73(1) Å, Z
= 4, R 0·038 for
No 866).
Phenyl Chloro(thionoformate): a New Dealkylating Agent of Tertiary Amines
Authors: Millan David S. , Millan David S. , Prager Rolf H. , Prager Rolf H.
Published: December 2005

Phenyl chloro(thionoformate) reacts rapidly with unhindered tertiary aliphatic
amines at 20° to give a thiocarbamate and an alkyl chloride.
Dialkylcyclohexylamines react surprisingly rapidly to form predominantly
cyclohexene. The thiocarbamates are converted into the secondary amine salt by
treatment with dimethyl sulfate, followed by hydrolysis with water. Rates of
reaction and alkyl group cleavage selectivity in amines were found to be
superior or comparable to those previously reported with
chloroformates.
Structural and Electronic Properties of the Iron(II) and Nickel(II) Bis(ligand) Complexes of 6-(5-Methyl-1,2,4-oxadiazol-3-yl)-2,2′-bipyridine— a Terpyridine-Based Tridentate
Authors: Childs Bradley J. , Scudder Marcia L. , Craig Donald C. , Goodwin Harold A.
Published: December 2005

Iron(II) and nickel(II) bis(ligand) complexes of
6-(5-methyl-1,2,4-oxadiazol-3-yl)-2,2′-bipyridine (L) are described. The
ligand field in the iron complex is close to that at the singlet (
1 A1) ? quintet (
5 T2) crossover and magnetic and
Mössbauer spectral evidence indicates that a spin transition occurs in
salts of the iron complex but is centred above room temperature. The
structures of [FeL2]
[CF3SO3]2.CH3CN
and [NiL2]
[BF4]2.CH3CN
were determined and both are very similar to the structures of the
corresponding terpyridine complexes. Spectroscopic data indicate that for the
iron complex π-interaction between the metal and the ligand is less than
that in the terpyridine system. [FeL2]
[CF3SO3]2.CH3CN
is monoclinic, space group P
21/c; a
8 . 232(5), b 25 . 273(10),
c 17 . 306(10) Å, β 92 .
37(3)°, Z 4; [NiL2]
[BF4]2.CH3CN
is monoclinic, space group P
21/c; a
8 . 136(2), b 17 . 558(2),
c 23 . 783(7) Å, β 109 .
32(1)°, Z 4.
Peptides from the Skin Glands of the Australian Buzzing Tree Frog Litoria electrica. Comparison with the Skin Peptides of the Red Tree Frog Litoria rubella
Authors: Wabnitz Paul A. , Bowie John H. , Wallace John C. , Tyler Michael J.
Published: December 2005

Eleven peptides have been isolated from the skin glands of the ‘buzzing
tree frog’ Litoria electrica. The two most
abundant peptides are tryptophyllin L 3.1 [Phe Pro Trp Pro
(NH2)] and electrin 1 [Phe Val Pro Ile Tyr Met
(NH2)]. These peptides show neither significant
antimicrobial nor smooth muscle activity. Tryptophyllin L 3.1 is thought to be
a neuromodulator or neurotransmitter, and it is similar in structure to the
human endomorphins [e.g. Tyr Pro Trp Phe
(NH2)] which act on the γ-receptor. Both
Litoria electrica and the ‘red tree frog’
Litoria rubella produce tryptophyllin peptides: it is
considered that both species evolved from the same
ancestor.
Synthesis and Binding Studies of Trishomocubanes: Novel Ligands for σ Binding Sites
Authors: Liu Xiang , Kassiou Michael , Christie MacDonald J.
Published: December 2005

Five new analogues of the
σ2-selective trishomocubane
N-(3′-fluorophenyl)methyl-4-azahexacyclo-
[5.4.1.0 2;6 .0
3;10 .0
5;9 .0
8;11 ]dodecan-3-ol (2) have
been synthesized and assessed for their anities at both
σ1 and
σ2 sites. The structural
requirements which influence σ binding of
functionalized trishomocubanes were investigated with a view to develop more
potent σ ligands, with particular emphasis on the
σ2 subtype. All synthesized
compounds displayed moderate anity to σ binding
sites. Binding at the σ1
site ranged from 107 to 1100 nМ while binding at the
σ2 site ranged from 135 to
250 nМ. The subtype selectivity was influenced by the nature and position
of substitution on the aromatic ring. Fluorine substitution in the
meta position, as in (2), is favoured over
ortho, or para or
meta and para difluoro
substitution for σ2
selectivity. Compounds (3)–(5) not only demonstrated lower anity at the
σ2 site but a reversal of
subtype selectivity with preferential binding at the
σ1 site
(σ1/σ2:
0 . 8 for (3); 0 . 4 for (4); 0 . 8 for (6)). Introduction of
CF3 and NO2 groups into the
meta position in compounds (6) and (7) retained
σ2 selectivity although to a
lesser extent when compared to (2)
(σ1/σ2:
7 . 6 for (2); 2 . 0 for (6); 4 . 5 for
(7)).
Partition of Microamounts of Some M2+ Ions During MgSO4.7H2O Crystallization
Authors: Smolik Marek
Published: December 2005

Partition coefficients (D) of trace amounts of
Ni2+, Co2+,
Zn2+, Cd2+,
Cu2+, Mn2+,
Ca2+, and Fe2+ have been
determined during crystallization of
MgSO4.7H2O. Their dependences on
the ionic radii of the M2+ ions, solubilities and
structures of the corresponding sulfates, as well as the abilities of the
microcomponents to form solid solutions with
MgSO4.7H2O have been analysed. The
D values are in the range from <0·005
(DCa) to 1·13
(DNi) and depend mainly on the
ionic radii of the M2+ ions, as well as the
structures of the corresponding sulfates and the ability to form solid
solutions with the macrocomponent.
Synthesis, Crystal Structure and Characterization of [Bis { N,N′ -bis(2-aminoethyl) propane-1,3-diamine} (µ- imidazolato-N,N′)dizinc(II)] Triperchlorate
Authors: Zhu Hai-Liang , Tong Ye-Xiang , Zhao Jing , Chen Xiao-Ming , Duan Chun-Ying , Tang Wen-Xia
Published: December 2005

The title compound
[Zn2(2,3,2-tet)2(Im)]
(ClO4)3
(C17H43Cl3N10O12Zn2,
2,3,2-tet =
N,N′-bis(2-
aminoethyl)propane-1,3-diamine, Im = imidazolate anion) consists of an
imidazolate-N,N′-bridged
binuclear cation and three perchlorate anions. The complex crystallizes in the
monoclinic space group C 2 with a
12 . 038(8), b 12 . 245(8),
c 11 . 902(3) Å, β
108 . 00(5)°, V 1668 . 6(15)
Å3 . The coordination geometry at each zinc(II)
centre is approximately square-pyramidal. The Zn . . . Zn
separation is 6 . 114(9) Å. Cyclic voltammetry shows two
irreversible cathodic waves at − 1 . 00 and − 1 . 08
V/s.c.e., which clearly indicates that coordination of the strong-field
ligands provides significant stability to the zinc(II) centre in the title
complex.
A Stereoselective Synthesis of 2,6-Dideoxy-6,6,6-trifluoro-arabino-hexoses via an Asymmetric Diels - Alder Strategy
Authors: Hayman Colin M. , Hanton Lyall R. , Larsen David S. , Guthrie Jenness M.
Published: December 2005

The enantioselective syntheses of each enantiomer of ethyl
2,6-dideoxy-6,6,6-trifluoro-β-arabino-hexopyranoside
(3) and of 2,6-dideoxy-6,6,6-trifluoro-arabino-hexose
(4) are described. The key step in the approach is the inverse electron demand
Lewis acid catalysed Diels–Alder reaction of the heterodiene
(E)-1,1,1-trifluoro-4-[(1R)-1-
phenylethoxy]but-3-en-2-one (5) and either ethyl vinyl ether (7a) or
benzyl vinyl ether (7b). The titanium(IV) chloride catalysed cycloadditions at
low temperature displayed high endo-selectivity and
modest diastereofacial selectivity. Hydroboration of the mixture of the
cis-cycloadducts (8a) afforded the separable
diastereoisomers (9a) and (10a). Hydrogenolysis of (9a) gave ethyl
2,6-dideoxy-6,6,6-trifluoro-β-L-arabino-hexopyranoside
(+)-(3), and of (10a) gave the corresponding D-glycoside (−)-(3).
Similarly, hydroboration of the cis-cycloadducts (8b)
gave the protected benzyl glycosides (9b) and (10b). Hydrogenolysis of each
gave 2,6-dideoxy-6,6,6-trifluoro-L-arabino-hexopyranose
(−)-(4) and the corresponding D-sugar (+)-(4) respectively. The
absolute configurations of fluorinated carbohydrates (+)- and
(−)-(3) were determined by comparison of their molar rotations with
those of the parent glycosides. These assignments were confirmed by an X-ray
crystallographic structure determination of the glycoside (9a).
Polymer-Supported N-Alkyl-α ,α-diphenyl-L- prolinols as Catalysts forthe Alkylation of Aldehydes Using Diethylzinc.
Authors: Hodge Philip , Kell Roger J. , Ma Jianbiao , Morris Hugh
Published: December 2005

Polystyrene beads containing
N-alkyl-α,α-diphenyl-L-prolinol moieties (7)
linked to the support via a long N-alkyl group, which
also serves as a spacer chain, have been prepared. When used to catalyse the
reactions of aldehydes with diethylzinc at 10 mole % in toluene at
20°C they afford the expected alcohols in 59–83% e.e. Where
comparisons can be made with the results obtained with
N-methyl-α,α-diphenyl-L-prolinol (3), the
PS(polymer- supported) catalysts afford lower percentage e.e. values. Evidence
is provided that this is due in part to the presence of the spacer chain, and
in part because with the PScatalysts not all the catalyst sites are readily
accessible. The latter means that the PScatalysts cannot compete
satisfactorily with the uncatalysed reactions between aldehydes and
diethylzinc which produce racemates. Thus, if higher percentage e.e. values
are to be obtained in future with PS α,α-diphenyl-L-prolinol
derivatives, the catalyst sites will most likely need to be bound to the
polymer via the phenyl groups or substituents on the five-membered ring.
The Preparation, Spectroscopic Characterization and X-Ray Structure of the Salt [Pt(η1 -C6H9)(Cy2PCH2CH2PCy2)(PPh3)]HCO3·3H2O Containing the Discrete, Uncoordinated, Hydrogen-Bonded Dimeric Bicarbonate Dianion [(HCO3)(H2O)3]22-
Authors: Bennett Martin A. , Robertson Glen B. , Kapoor Pramesh N.
Published: December 2005

Reaction of the cyclohexyne–platinum(0) complex
[Pt(η2-C6H8)(Cy2PCH2CH2PCy2)]*
with water and CO2 in the presence of triphenylphosphine
gives the bicarbonate salt of the
(η1-cyclohexenyl)platinum(II) cation,
[Pt(η1-C6H9)(Cy2PCH2CH2
PCy2)(PPh3)]
[HCO3] · 3H2O,
which has been characterized by n.m.r. spectroscopy and single-crystal X-ray
diffraction at low temperature. Crystals are triclinic, space group
P1– with unit cell
dimensions a 20.315(2), b
12.782(1), c 10.694(1) Å, α 66.61(1), β
104.73(1), γ 102.11(1)˚, and Z 2. The structure
was refined to a final R value of 0.036 with use of 7553
reflections [I >
3σ(I)]. The cation has the expected, somewhat
distorted planar coordination geometry; the anion consists of discrete,
hydrogen-bonded dimers
[(HCO3)(H2O)3]22-.
Pigments of Fungi. LXI. Anhydroflavomannin-9,10-quinone 6,6´,8´-Tri-O-methyl Ether from an Australian Dermocybe Toadstool
Authors: Gill Melvyn , Yu Jin , Raudies Evelin
Published: December 2005

Anhydroflavomannin-9,10-quinone
6,6´,8´-tri-O-methyl ether (4) is isolated
from the Australian toadstool Dermocybe sp. WAT 24274
and its structure and stereochemistry are determined by spectroscopic methods.
Synthesis of 123I-Labelled Analogues of Imidazobenzodiazepine Receptor Ligands.
Authors: McPhee Meredith E. , Katsifis Andrew G. , Mattner Filomena , Ridley Damon D.
Published: December 2005

Reaction of bromo- or iodo-substituted isatoic anhydrides with
N-methylglycine, L-proline or D-proline afforded bromo-
or iodo-substituted 1,4-benzodiazepinediones which on condensation with ethyl
or t-butyl isocyanoacetates gave ethyl or t-butyl bromo- or
iodo-imidazobenzodiazepine carboxylates. These aryl halides were converted
into the corresponding tributylstannanes with bis(tributyltin) in the presence
of (triphenylphosphine)palladium(0), and the stannanes were treated with
sodium (123I)iodide in the presence of chloramine-Tto
give the required 123I- labelled analogues of the
imidazobenzodiazepine receptor ligands flumazenil and bretazenil.
The Dimerization and Cyclotrimerization of Acetylenes Mediated by Phosphine Complexes of Cobalt(I), Rhodium(I), and Iridium(I).
Authors: Field Leslie D. , Ward Antony J. , Turner Peter
Published: December 2005

The catalytic dimerization and cyclotrimerization of phenylacetylene, ethyl
propiolate, and dimethyl acetylenedicarboxylate were studied by using the
metal complexes
[Co(PPh3)3Cl] (1),
[Co(PPh3)2(CO)2Cl]
(2), [Co(PMe3)3Cl] (3),
[Co(PMe3)2(CO)2Cl]
(4), [Rh(dppe)(CO)Cl] (5),
[Rh(PPh2Me)2(CO)Cl] (6),
[Ir(dppe)(CO)Br] (7), and
[Ir(PPh2Me)2(CO)Cl] (8).
For all complexes studied, with terminal acetylene substrates, there is
competition between head-to-head dimerization to form 1,4-disubstituted
butenynes and cyclotrimerization to form 1,3,5- or 1,2,4-trisubstituted
benzenes. The metallocyclopentadiene [Ir(dppe)(CO)(L)Br] (L=
1,4- diethoxycarbonylbuta-1,3-diene-1,4-diyl) was formed in the reaction of
diethyl acetylenedicarboxylate with [Ir(dppe)(CO)Br] (7), and this
stable complex is a possible intermediate in the cyclotrimerization of the
acetylene. The metallocyclopentadiene was fully characterized by X-ray
crystallography. Crystal data for the benzene solvate of (33),
C43H42BrIrO5P2
at 21°C: space group
P21/c
(No. 14), a 8.774(4), b 22.155(3),
c 20.242(2) Å, β
92.46(2)˚, V 3931(1) Å3
, Z 4, No
4804, Nvar 469,
R(F) 0.0411,
Rw(F)
0.0483.
Di-μ-olato dinuclear copper(II) compounds. The structure of bis-μ-O-[(4,6,6-trimethyl-9-(pyridin-2-yl)-3,7-diazanon-3-en-1-olato)copper(II)] perchlorate
Authors: Curtis Neil F. , Gladkikh Olga P. , Morgan Keith R. , Heath Sarah L.
Published: December 2005

Preparations are reported for blue-green[{Cu(pyen)(eto)}2](ClO4)2[pyen is 2-(2-aminoethyl)pyridine, eto– isdeprotonated 2-aminoethanol] and of green[{Cu(pyaceto)}2](ClO4)2,formed by reaction of this compound with acetone[pyaceto– is deprotonated4,6,6-trimethyl-9-(pyridin-2-yl)-3,7-diazanon-3-en-1-ol]. The structureof[{Cu(pyaceto)}2](ClO4)2shows a unit cell containing two independent, but closely similar,centrosymmetrical dinuclear diolato-bridged cations. The copper(II) ions arein square pyramidal coordination, with the two bridging oxygen atoms, and theimine and secondary amine nitrogen atoms in the basal plane, with the pyridinenitrogen atom more weakly coordinated axially. Mean dimensions for the twocations are Cu–Cu# 2.99, Cu–Nbasal 2.01,Cu–O 1.96, Cu–Naxial 2.24 Å,O–Cu–O# 99, Cu–O–Cu# 81, C–O–Cu110, C–O–Cu# 130˚[C30H46Cl2Cu2N6O10,monoclinic, space group P21/n, a 13.487(1),b 13.356(1), c 20.921(2) Å,β 103.235(3)˚, R1 = 0.0516 for 4694reflections]. Magnetic susceptibilities (100–300 K) showantiferromagnetic spin coupling for[{Cu(pyaceto)}2](ClO4)2and[{Cu(pyen)(eto)}2](ClO4)2with singlet–triplet level separation J of–110(10) and –65(10) cm–1,respectively, indicating that[{Cu(pyen)(eto)}2](ClO4)2also has a dinuclear structure.
Lime improves emergence of canola on an acidic, hardsetting soil
Authors: Scott B. J. , Fleming M. R. , Conyers M. K. , Chan K. Y. , Knight P. G.
Published: December 2005

Much of the agricultural lime applied in southern New South Wales, Australia, is applied to crops of canola (Brassica napus L.), but little is documented on the response of canola to lime. The few documented responses in grain yield of canola to lime application have been ascribed to decreased toxicities of aluminium and manganese. However, there is evidence that lime can have a structural effect on soil. A field experiment was limed in 1982 (0–5 t/ha) and was relimed in 1996 (0–5 t/ha) to give factorial combinations of 5 rates of 'old' (1982) and 6 rates of 'new' (1996) lime. When sown to canola in 1999 there was an increase in density of canola (from 17�to�60�plants/m2) and grain yield (from 1200 to 2700 kg/ha) associated with increasing rates of lime application. The emergence of canola was increased by 15% for each 1 unit increase in soil pHCa. Two subsequent pot experiments, conducted on cores taken from a subset of field plots with different liming histories, showed that lime application increased emergence of canola by about 9% for each 1 unit increase in soil pHCa. In addition, 2 contrasting watering treatments (gentle spraying and rapid flooding) were applied to the pots to either avoid or accentuate any soil structural breakdown. Flooding gave lower emergence compared with spraying (19 and 31%, respectively). Soil strength measurements (penetration resistance and shear strength) conducted on the surface soil (0–1 cm depth) during the second glasshouse experiment showed that lime application and gentle watering (spraying rather than flooding) resulted in lower soil strength. The soil strength measurements were related to emergence of canola. It is proposed that soil structural stability was the major contributor to these observed emergence differences. This is the first evidence in New South Wales of lime affecting plant performance via its influence on soil structure.
The influence of cultivar and environment on the chlorophyll concentration of Australian canola seed
Authors: Mailer R. J. , Orchard B. , Vonarx M. M. , Wratten N.
Published: December 2005

The chlorophyll content of mature seeds of Australian canola was studied to determine breeding line and environmental effects. The canola lines tested included a large number of commercial cultivars as well as lines from the major canola-breeding programs. The lines represented 5 groups based on maturity and group 6 consisting of triazine-tolerant types. Trials were grown at 64 sites throughout the canola-growing area of Australia in 2000. An NIR Systems 6500 spectrophotometer, calibrated to measure chlorophyll, was used to analyse the large number of samples. For each group, chlorophyll content was modelled using a linear mixed model which included site, line and site × line effects. Both line and site × line effects were significant (P<0.05) in all analyses. The line effect indicates that, while the environment is the major determinant of chlorophyll, selection may be possible in breeding programs, utilising rapid NIR techniques, to select for lines least likely to retain chlorophyll in mature seeds.
The Sustainable Grazing Systems Pasture Model: description, philosophy and application to the SGS National Experiment
Authors: Johnson I. R. , Lodge G. M. , White R. E.
Published: December 2005

A biophysical simulation model (the Sustainable Grazing Systems Pasture Model) was developed as an integral part of the Sustainable Grazing Systems National Experiment. It was developed to meet the needs of the researchers both for analysing data and processes at individual sites, and for simulating the outcome of these processes operating in generic pasture systems on a range of soil types, under specific grazing managements. The model was designed to reside on the desktops of individual researchers and for those researchers to be part of its development process.The Sustainable Grazing Systems Pasture Model incorporates the following: a physiological model of pasture species herbage accumulation in response to climatic conditions; the water balance including evapotranspiration, runoff (surface and subsurface), infiltration and drainage; pasture utilisation by grazing animals; a metabolisable energy-based animal growth model; and organic matter and inorganic nutrient dynamics (for nitrogen, phosphorus, potassium and sulfur) including plant uptake, adsorption, leaching, nitrogen fixation by legumes, and atmospheric nitrogen losses. A range of grazing options (set-stocking, rotational grazing and continuous grazing at a variable rate) is available for ewes and lambs, and wethers. Each of the main modules (water, nutrients, pastures and animals) is interconnected. To avoid bias in the influence of any one module, each is described at about the same level of complexity, with the description of any process being restricted to about 5 parameters. The model is hierarchical in structure and most processes are described in terms of a series of fluxes (or, more specifically, flux densities) that have dimensions of amount per area per time.The model can be closely linked to a database specifically developed for the Sustainable Grazing Systems National Experiment to allow easy importing and exporting of climate and experimental data for comparison with model output. This paper gives an overview of the model structure and its output, the process that was used for its development within Sustainable Grazing Systems, and its use by the Sustainable Grazing Systems sites and themes. Comments are provided on the implementation of the development process to assist future programs using a similar approach.
The role of plants and plant-based research and development in managing dryland salinity in Australia
Authors: Ridley A. M. , Pannell D. J.
Published: December 2005

The roles of plant-based systems and plant-based research and development for management of dryland salinity in southern Australia vary over a range of biophysical and socio-economic conditions, and differ according to the resources at risk (protection of water resources, biodiversity, infrastructure, dispersed assets such as agricultural land, and salt-affected land). Recommended responses are sensitive to a range of biophysical and socio-economic conditions. Extension and incentives to promote currently available perennials or salt-tolerant plants are only appropriate as the main policy response in a minority of cases. Regulation or permits to limit planting of perennials can be justified in certain areas of high-water-yielding catchments. For the majority of agricultural land that is at risk or is contributing to dryland salinity, the most logical policy response is to invest in development to improve salinity management technologies, including research and development into new plant-based systems. Situations where plant-based R&D for profitable farming systems is the best option include: (i) to reduce salinity impacts on water resources where groundwater systems are responsive and the dependence on fresh runoff for consumptive use is low; (ii) to protect infrastructure and biodiversity where there is relatively high responsiveness of groundwater and the urgency of response is low; (iii) to protect dispersed assets (e.g. agricultural land, most remnant vegetation on farms, flood risk mitigation) where profitable perennial plant options are lacking; and (iv) for land that is already salt affected.
Mineral nutrition of soybeans grown in the south Burnett region of south-eastern Queensland. I. Effect of phosphorus, potassium, calcium and sulfur on grain yield and plant composition
Authors: Dickson T , Haydon GF , Dwyer JC
Published: December 2005

Twenty-seven field experiments were carried out over the period 1973 to 1977 with soybeans Glycine max(L.) Merrill cv. Bragg on krasnozem, euchrozem and xanthozem soils in the South Burnett region of Queensland to study effects of phosphorus, potassium, calcium and sulfur on grain yield and plant nutrient composition. Grain yield responses (P< 0.01) were associated with increased seed number rather than heavier grain weights. These were recorded at approximately 30% of the 27 sites that received 20 or 40 kg P/ha and on 25% of 17 sites after an application of 50 kg K/ha. No yield gains were measured from applications of calcium and sulfur. Moisture stress from anthesis to maturity restricted grain production in all years but only in one were responses to applied nutrients seriously reduced. Indices for the attempted prediction of yield responses to applied elements were derived from the concentration of elements in leaves and whole tops collected at anthesis. Mean leaf phosphorus concentrations were 0.24% in control plots and 0.26% in fertilized treatments. No relation between leaf phosphorus and response to applied phosphorus could be established but leaf potassium concentration in control treatments averaged 0.66% at responsive sites and 1.64% at non-responsive sites.
Effect of quantity and frequency of application of superphosphate on the seasonal yield of annual pasture
Authors: McGowan AA , Cameron IH , White DH
Published: December 2005

An experiment compared the effectiveness of annual and quadrennial applications of superphosphate (totalling 24,48 or 72 kg P/ha over four years) in increasing the winter and spring yield of annual pasture. Initial levels of superphosphate of 12, 84 or 156 kg P/ha had been applied in the preliminary year of the experiment. Over the next four years there was no response to subsequent application of superphosphate after an initial application of 156 kg P/ha, or early in the experiment, after an initial application of 84 kg P/ha. However, whenever the pasture did respond to subsequent topdressing, annual applications produced a greater total response in winter over four years than did a single initial application of four times the annual rate; with the low initial rate of application, this benefit was 1.5 t dry matter/ha overthe four year period. Frequency of application did not affect responses in the spring. Pasture yield was described by the model: yield =a - b exp (- c.SP) where SP is available soil phosphorus based on the model SPn = +i =i0 Pi (1 - V) n -I n being the year of experiment, Pi the rate of phosphorus applied in year i, and V the annual decay rate of applied phosphorus in the soil. The level of soil phosphorus, extractable by acetic acid at the end of the experiment, was related to the total amount of fertilizer applied during the previous five years, but was not shown to be related to the frequency of application. Estimates of the annual decay rate of the applied phosphorus ranged from 19 to 75%.
Variation in the rate of hard seed breakdown of twelve tropical legumes in response to two temperature regimes in the laboratory
Authors: McDonald C. K.
Published: December 2005

Hard seed content is an important factor in
the persistence of tropical pasture legumes as both high and low hard seed
content can lead to poor recruitment. As temperature plays an important role
in the breakdown of hard seed, the patterns of breakdown were measured in 27
seed lots of tropical legumes subjected to temperature regimes of
23–57˚C and 23–70˚C in laboratory ovens for 7 months.
The seed lots represented 12 species comprising 15 released cultivars and 5
accessions showing promise in field evaluation studies.
Each month seed was removed for germination testing and the proportion of
hard, soft and dead seed in each seed lot was determined. After 7 months, the
resulting pattern of hard seed breakdown was modelled to derive threshold
temperatures for hard seed breakdown, values for the breakdown rate and
quantification of the breakdown process.
Desmanthus virgatus and
Indigofera schimperi had the slowest rate of breakdown,
while Aeschynomene americana had the fastest. The
threshold temperature for most species was in the range 40–50˚C.
However, there was considerable variation in threshold temperature and
breakdown rates between seed lots of the same cultivar or accession and
between species, which indicates that caution must be used before
extrapolating the results to the field and to different climatic and/or
management environments.
Nevertheless, these results provide valuable information for the development
of demographic models of legume persistence, and show that, while the species
are well adapted to the temperature environments of northern Australia,
specific management may be necessary to enhance the persistence of some of
them.
Bisphosphonate-mediated gene vector delivery from the metal surfaces of stents
Authors: Fishbein Ilia , Alferiev Ivan S. , Nyanguile Origene , Gaster Richard , Vohs John M. , Wong Gordon S. , Felderman Howard , Chen I-Wei , Choi Hoon , Wilensky Robert L. , Levy Robert J.
Published: December 2005

The clinical use of metallic expandable intravascular stents has resulted in improved therapeutic outcomes for coronary artery disease. However, arterial reobstruction after stenting, in-stent restenosis, remains an important problem. Gene therapy to treat in-stent restenosis by using gene vector delivery from the metallic stent surfaces has never been demonstrated. The present studies investigated the hypothesis that metal–bisphosphonate binding can enable site-specific gene vector delivery from metal surfaces. Polyallylamine bisphosphonate (PAA-BP) was synthesized by using Michael addition methodology. Exposure to aqueous solutions of PAA-BP resulted in the formation of a monomolecular bisphosphonate layer on metal alloy surfaces (steel, nitinol, and cobalt–chromium), as demonstrated by x-ray photoelectron spectroscopy. Surface-bound PAA-BP enabled adenoviral (Ad) tethering due to covalent thiol-binding of either anti-Ad antibody or a recombinant Ad-receptor protein, D1. In arterial smooth muscle cell cultures, alloy samples configured with surface-tethered Ad were demonstrated to achieve site-specific transduction with a reporter gene, (GFP). Rat carotid stent angioplasties using metal stents exposed to aqueous PAA-BP and derivatized with anti-knob antibody or D1 resulted in extensive localized Ad-GFP expression in the arterial wall. In a separate study with a model therapeutic vector, Ad-inducible nitric oxide synthase (iNOS) attached to the bisphosphonate-treated metal stent surface via D1, significant inhibition of restenosis was demonstrated (neointimal/media ratio 1.68 ± 0.27 and 3.4 ± 0.35; Ad-iNOS vs. control,
P
< 0.01). It is concluded that effective gene vector delivery from metallic stent surfaces can be achieved by using this approach.
Structural genomics analysis of alternative splicing and application to isoform structure modeling
Authors: Wang Peng , Yan Bo , Guo Jun-tao , Hicks Chindo , Xu Ying
Published: December 2005

Alternative splicing is a sophisticated nuclear process that regulates gene expression. It represents an important mechanism for enhancing the functional diversity of proteins. Our current knowledge of alternatively spliced variants is derived mainly from mRNA transcripts, and very little is known about their protein tertiary structures. We carried out a large-scale analysis of known alternatively spliced variants at both protein sequence and structure levels and have shown that threading is, in general, a viable approach for modeling structures of alternatively spliced variants. An examination of alternative splicing at the protein sequence level revealed that the size of splicing events follows the power law distribution and the majority of splicing isoforms harbor only one or two alternations. We examined alternative splicing in the context of protein 3D structures and found that the boundaries of alternative splicing events generally happen in coil regions of secondary structures and exposed residues and the majority of the sequences involved in splicing are located on the surface of proteins. In light of these findings, we then proceeded to demonstrate that threading represents a useful tool for structure prediction of alternative splicing isoforms and addressed the fold stability issue of threading-based structure prediction by molecular dynamics simulation. Our analysis and the insights gained have helped to establish a viable method for structure prediction of alternatively spliced isoforms at the genome scale.
Molecular cloning, expression, and structural prediction of deoxyhypusine hydroxylase: A HEAT-repeat-containing metalloenzyme
Authors: Park Jong-Hwan , Aravind L. , Wolff Edith C. , Kaevel Jörn , Kim Yeon Sook , Park Myung Hee
Published: December 2005

The eukaryotic initiation factor 5A (eIF5A), a factor essential for eukaryotic cell proliferation, is the only cellular protein containing the polyamine-derived amino acid hypusine [N
ε
-(4-amino-2-hydroxybutyl)lysine]. Hypusine is formed in a posttranslational modification that involves two sequential enzymatic steps catalyzed by deoxyhypusine synthase and deoxyhypusine hydroxylase (DOHH). By screening a
Saccharomyces cerevisiae
GST-ORF library for expression of DOHH activity, we have cloned
YJR070C
as the gene encoding DOHH and identified the human homolog DOHH gene,
HLRC1
. Purified recombinant yeast and human DOHH enzymes effectively catalyzed hydroxylation of the deoxyhypusine residue in the eIF5A intermediate. Overexpression of human DOHH along with eIF5A precursor and deoxyhypusine synthase was required for overproduction of mature, hypusine-containing eIF5A in 293T and other mammalian cells. The
Saccharomyces cerevisiae
strain with deletion of
YJR070C
contained only deoxyhypusine but no hypusine, indicating that
YJR070C
was the single DOHH gene in this organism. One highly conserved DOHH homolog gene is found in a variety of eukaryotes from yeast to human. Sequence and structural analyses reveal that DOHH belongs to a family of HEAT-repeat-containing proteins, consisting of eight tandem repeats of an α-helical pair (HEAT motif) organized in a symmetrical dyad. The predicted structure is unrelated to the double-stranded β-helix type structures of the Fe(II)- and 2-oxoacid-dependent dioxygenases, such as collagen prolyl or lysyl hydroxylases. However, metal coordination sites composed of four strictly conserved histidine–glutamate sequences were identified, suggesting that DOHH enzymes have convergently evolved an iron-dependent hydroxylation mechanism.
Regulation of dendritic cell maturation and function by Bruton's tyrosine kinase via IL-10 and Stat3
Authors: Kawakami Yuko , Inagaki Naoki , Salek-Ardakani Shahram , Kitaura Jiro , Tanaka Hiroyuki , Nagao Koichi , Kawakami Yu , Xiao Wenbin , Nagai Hiroichi , Croft Michael , Kawakami Toshiaki
Published: December 2005

Btk plays crucial roles in the differentiation and activation of B and myeloid cells. Despite drastic reductions of other Ig isotypes, paradoxically high IgE responses have been known inbtkmutant mice. Here we show thatbtk–/–dendritic cells exhibit a more mature phenotype and a strongerin vitroandin vivoT cell-stimulatory ability than wild-type cells. Increased IgE responses were induced by adoptive transfer ofbtk–/–dendritic cells into mice. Consistent with the stronger T cell-stimulatory ability ofbtk–/–dendritic cells,btk–/–mice exhibited enhanced inflammation in Th2-driven asthma and Th1-driven contact sensitivity experiments. These negative regulatory functions of Btk in dendritic cells appear to be mediated mainly through autocrine secretion of IL-10 and subsequent activation of Stat3.
The questionable contribution of the Neolithic and the Bronze Age to European craniofacial form
Authors: Brace C. Loring , Seguchi Noriko , Quintyn Conrad B. , Fox Sherry C. , Nelson A. Russell , Manolis Sotiris K. , Qifeng Pan
Published: December 2005

Many human craniofacial dimensions are largely of neutral adaptive significance, and an analysis of their variation can serve as an indication of the extent to which any given population is genetically related to or differs from any other. When 24 craniofacial measurements of a series of human populations are used to generate neighbor-joining dendrograms, it is no surprise that all modern European groups, ranging all of the way from Scandinavia to eastern Europe and throughout the Mediterranean to the Middle East, show that they are closely related to each other. The surprise is that the Neolithic peoples of Europe and their Bronze Age successors are not closely related to the modern inhabitants, although the prehistoric/modern ties are somewhat more apparent in southern Europe. It is a further surprise that the Epipalaeolithic Natufian of Israel from whom the Neolithic realm was assumed to arise has a clear link to Sub-Saharan Africa. Basques and Canary Islanders are clearly associated with modern Europeans. When canonical variates are plotted, neither sample ties in with Cro-Magnon as was once suggested. The data treated here support the idea that the Neolithic moved out of the Near East into the circum-Mediterranean areas and Europe by a process of demic diffusion but that subsequently the
in situ
residents of those areas, derived from the Late Pleistocene inhabitants, absorbed both the agricultural life way and the people who had brought it.
Evidence for the direct involvement of βTrCP in Gli3 protein processing
Authors: Wang Baolin , Li Yanyun
Published: December 2005

Hedgehog-regulated processing of the transcription factor cubitus interruptus (Ci) in
Drosophila
depends on phosphorylation of the C-terminal region of Ci by cAMP-dependent protein kinase and subsequently by casein kinase 1 and glycogen synthase kinase 3. Ci processing also requires Slimb, an F-box protein of SCF (
S
kp1/
C
ullin/
F
-box proteins) complex, and the proteasome, but the interplay between phosphorylation and the activity of Slimb and the proteasome remains unclear. Here we show that processing of the Gli3 protein, a homolog of Ci, also depends on phosphorylation of a set of four cAMP-dependent protein kinase sites that primes subsequent phosphorylation of adjacent casein kinase 1 and glycogen synthase kinase 3. Our gain- and loss-of-function analyses in cultured cells further reveal that βTrCP, the vertebrate homolog of Slimb, is required for Gli3 processing, and we demonstrate that βTrCP can bind phosphorylated Gli3 both
in vitro
and
in vivo
. We also find that the Gli3 protein is polyubiquitinated in the cell and that its processing depends on proteasome activity. Our findings provide evidence for a direct link between phosphorylation of Gli3/Ci proteins and βTrCP/Slimb action, thus supporting the hypothesis that the processing of Gli3/Ci is affected by the proteasome.
Do Transposed-Letter Similarity Effects Occur at a Prelexical Phonological Level?
Authors: Perea Manuel , Carreiras Manuel
Published: December 2005

Nonwords created by transposing two letters (e.g., RELOVUTION) are very effective at activating the lexical representation of their base words (Perea & Lupker, 2004). In the present study, we examined whether the nature of transposed-letter (TL) similarity effects was purely orthographic or whether it could also have a phonological component. Specifically, we examined transposed-letter similarity effects for nonwords created by transposing two nonadjacent letters (e.g., relovución– REVOLUCIÓN) in a masked form priming experiment using the lexical decision task (Experiment 1). The controls were (a) a pseudohomophone of the transposed-letter prime ( relobución– REVOLUCIÓN; note that B and V are pronounced as /b/ in Spanish) or (b) an orthographic control ( relodución– REVOLUCIÓN). Results showed a similar advantage of the TL nonword condition over the phonological and the orthographic control conditions. Experiment 2 showed a masked phonological priming effect when the letter positions in the prime were in the right order. In a third experiment, using a single-presentation lexical decision task, TL nonwords produced longer latencies than the orthographic and phonological controls, whereas there was only a small phonological effect restricted to the error data. These results suggest that TL similarity effects are orthographic—rather than phonological—in nature.