bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of OxyE as an Ancillary Oxygenase during Tetracycline Biosynthesis
Authors: Wang Peng , Zhang Wenjun , Zhan Jixun , Tang Yi
Published: May 2009

Ancillary oxygenase: OxyE is identified as a likely ancillary C‐4 hydroxylase used during oxytetracycline biosynthesis in Streptomyces rimosus. The synergistic actions of oxygenases OxyE and OxyL ensure complete oxidative tailoring and prevent irreversible shunt modifications of the biosynthetic intermediate.

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The double hydroxylation of 6‐pretetramid to 4‐keto‐anhydrotetracycline is a key tailoring reaction during the biosynthesis of the broad‐spectrum antibiotic tetracyclines. It has been shown previously by heterologous reconstitution that OxyL is a dioxygenase and is the only enzyme required to catalyze the insertion of oxygen atoms at the C‐12a and C‐4 positions. We report here that OxyE, a flavin adenine dinucleotide (FAD)‐dependent hydroxylase homologue, is an ancillary mono‐oxygenase for OxyL during oxytetracycline biosynthesis in Streptomyces rimosus. By using both gene disruption and heterologous reconstitution approaches, we demonstrated that OxyE plays a nonessential, but important role in oxytetracycline biosynthesis by serving as a more efficient C‐4 hydroxylase. In addition, we demonstrated that partially oxidized biosynthetic intermediates can undergo various glycosylation modifications in S. rimosus. Our results indicate that the synergistic actions of OxyE and OxyL in the double hydroxylation step prevent accumulation of shunt products during oxytetracycline biosynthesis in S. rimosus.
Periodic Mesoporous Organosilica in Confined Environments
Authors: Keilbach Andreas , Döblinger Markus , Köhn Ralf , Amenitsch Heinz , Bein Thomas
Published: May 2009

Confined tubes: Periodic mesoporous organosilica (PMO) mesophases were synthesized within the confined tubular environment of anodic alumina membrane (AAM) channels, resulting in the formation of either the hexagonal circular or the cubic mesophase.

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Periodic mesoporous organosilica (PMO) mesophases based on bis(triethoxysilyl)ethane (BTSE) were synthesized within the confined tubular environment of anodic alumina membrane (AAM) channels. The resulting mesophases were investigated by transmission small angle X‐ray scattering (SAXS), nuclear magnetic resonance (NMR), nitrogen sorption, and transmission electron microscopy (TEM). Two different surfactants—nonionic Brij 56 and ionic cetyltrimethylammonium bromide (CTAB)—were used in an acid‐catalyzed evaporation‐induced self‐assembly (EISA) process. Brij 56 as the structure‐directing agent (SDA) resulted in the formation of either the hexagonal circular or the cubic mesophase. While the hexagonal circular mesophase is common for such kinds of composites, the cubic mesophase has never been reported before. The template could be removed from the mesophases by template extraction and calcination after annealing the samples. When using CTAB as the SDA during EISA, the only mesophase observed was the hexagonal circular structure. This is in contrast to previous experiments and reports on pure silica mesophases, where the only mesophase formed with CTAB is hexagonal columnar.
Unusual Optical Properties of Mn‐doped ZnO: The Search for a New Red Pigment—A Combined Experimental and Theoretical Study
Authors: Saal Hilkka , Binnewies Michael , Schrader Marius , Börger Alexander , Becker Klaus‐Dieter , Tikhomirov Viatcheslav A. , Jug Karl
Published: May 2009

A pigment of your imagination: A range of polycrystalline solid solutions of a zinc‐rich Znx−1MnxO system (see figure) have been prepared and studied in terms of their colour, diffuse reflectance spectra, Mn valence state and electronic structure. The intense optical absorption arises from Mn2+ doping and is thought to be due to forbidden or partially forbidden transitions between the valence and the conduction band.

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We report an investigation of zinc‐rich polycrystalline solid solutions of the Zn1−xMnxO system concerning the colour, the diffuse reflectance spectra, the valence state of manganese and the electronic structure. Samples were prepared by a chemical‐vapour‐transport‐assisted route and optimized with respect to colour strength. In agreement with previous experimental results, EPR studies showed that manganese is in the divalent charge state. The nature of the very intense optical absorption, which is caused by Mn2+ doping and determines the colour of the material, is discussed. It is argued that the Mn2+‐induced optical absorption is due to forbidden or partially forbidden transitions between the valence and the conduction band that involve Mn admixed states. This assignment is also confirmed by quantum chemical calculations using the semiempirical molecular orbital method MSINDO.
Synthesis and Properties of Salen–Aluminum Complexes as a Novel Class of Color‐Tunable Luminophores
Authors: Hwang Kyu Young , Kim Hyoseok , Lee Yoon Sup , Lee Min Hyung , Do Youngkyu
Published: May 2009

Showing their true colors? Full emission color tuning in the visible region can be achieved with salen–aluminum complexes that are electronically modulated at C5 of the phenoxide ring in the salen moiety. Emission spectra for various substituents R5 are shown (EWG: electron‐withdrawing group, EDG: electron‐donating group).

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A series of salen–aluminum complexes, [{(R5)2‐salen(3‐tBu)2}Al(OC6H4‐p‐C6H5)] (salen=N,N′‐bis(salicylidene)ethylenediamine; R5=H (1), tBu (2), Br (3), Ph (4), OMe (5), NMe2 (6)) and [{5,5′‐(NMe3)2‐salen(3‐tBu)2}Al(OC6H4‐p‐C6H5)][OTf]2 (7; OTf=CF3SO3) that are electronically modulated directly at C5 of the phenoxide ring in the salen moiety has been prepared. The crystal structures of 1, 4, 6, and 7 determined by X‐ray diffraction reveal distorted square‐pyramidal geometries around the Al atoms. Complexes 1–7 are all air‐stable in both the solid and solution states and have high thermal stability (decomp 313–338 °C). Differential scanning calorimetric analyses show that they can form amorphous glasses with glass transition temperatures of 95–132 °C depending on the C5 substituent. UV/Vis absorption spectra of the complexes exhibit major bands at λ=338–413 nm assignable to salen‐centered π–π* transitions with a gradual red shift of the absorption maximum wavelengths as the substituent is varied from an electron‐withdrawing (NMe3) to an electron‐donating group (NMe2). The maxima in the emission spectra of 1–7 occur over the entire visible region, ranging from λ=438 nm for 7 to λ=599 nm for 6, with high fluorescence quantum efficiencies of up to Φ=0.40 for 4 in solution. DFT calculations suggest that the low‐energy electronic transitions in 1–7 are characterized by HOMO−i–LUMO+1 (i=1 for 1–6 or i=4 for 7) transitions localized on the salen moiety, with much involvement of the C5 position in the HOMO−i. Thus, the electronic alteration at the C5 position of the phenoxide ring, which mainly affects the HOMO−i energy levels of salen–Al luminophores, is responsible for the observed emission color‐tuning properties over the entire visible region.
Ti‐Substituted Boranes as Hydrogen Storage Materials: A Computational Quest for the Ideal Combination of Stable Electronic Structure and Optimal Hydrogen Uptake
Authors: Zhang Cheng‐Gen , Zhang Renwu , Wang Zhi‐Xiang , Zhou Zhen , Zhang Shengbai B. , Chen Zhongfang
Published: May 2009

Hydrogen storage: A family of Ti‐substituted boranes (see figure) having optimum electronic structures and the ability to absorb hydrogen has been designed computationally. Substantial binding energies and gravimetric densities of hydrogen storage show their potential as hydrogen storage materials. The computational study invites experimental synthesis of the novel borane family and offers a guide to searching for new hydrogen storage materials.

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Based on the Wade–Mingos n+1 rule for the closo‐boranes (BnHn2−), a family of Ti‐substituted closo‐boranes has been designed computationally. Due to the isolobal relation of Ti to a BH2− group, these Ti‐substituted boranes have n+1 pairs of skeletal electrons to fulfill the bonding requirement for such stable cages. The reported representatives, B4H4Ti2H2 in particular, not only have stable electronic structures but also superior capability to adsorb hydrogen. The optimal binding energies and high gravimetric densities of hydrogen storage indicate their potential to store hydrogen for practical applications. Simultaneously achieving electronic stability and optimal hydrogen uptake may provide a way of overcoming the issue of aggregation in designing transition‐metal‐decorated hydrogen storage materials. This study invites experimental realization of novel boranes and provides new ideas for searching for hydrogen storage materials.
Lys314 is a Nucleophile in Non‐Classical Reactions of Orotidine‐5′‐Monophosphate Decarboxylase
Authors: Heinrich Daniel , Diederichsen Ulf , Rudolph Markus Georg
Published: May 2009

Molecular versatility: Unusual reactivities such as hydrolysis, nucleophilic aromatic substitution, and addition reactions of human orotidine‐5′‐monophosphate decarboxylase are explained by crystal structures and involve a nucleophilic lysine residue that normally is expected to act solely as a general base (RP=phosphoribosyl, R=CO2H, CN, acetyl, N3, I; R′=OH, SH, acetyl, hydroxymethyl).

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Orotidine‐5′‐monophosphate decarboxylase (OMPD) catalyzes the decarboxylation of orotidine‐5′‐monophosphate (OMP) to uridine‐5′‐monophosphate (UMP) in an extremely proficient manner. The reaction does not require any cofactors and proceeds by an unknown mechanism. In addition to decarboxylation, OMPD is able to catalyze other reactions. We show that several C6‐substituted UMP derivatives undergo hydrolysis or substitution reactions that depend on a lysine residue (Lys314) in the OMPD active site. 6‐Cyano‐UMP is converted to UMP, and UMP derivatives with good leaving groups inhibit OMPD by a suicide mechanism in which Lys314 covalently binds to the substrate. These non‐classical reactivities of human OMPD were characterized by cocrystallization and freeze‐trapping experiments with wild‐type OMPD and two active‐site mutants by using substrate and inhibitor nucleotides. The structures show that the C6‐substituents are not coplanar with the pyrimidine ring. The extent of this substrate distortion is a function of the substituent geometry. Structure‐based mechanisms for the reaction of 6‐substituted UMP derivatives are extracted in accordance with results from mutagenesis, mass spectrometry, and OMPD enzyme activity. The Lys314‐based mechanisms explain the chemodiversity of OMPD, and offer a strategy to design mechanism‐based inhibitors that could be used for antineoplastic purposes for example.
A Cholesterol‐Based Tether for Creating Photopatterned Lipid Membrane Arrays on both a Silica and Gold Surface
Authors: Han Xiaojun , Achalkumar Ammathnadu S. , Bushby Richard J. , Evans Stephen D.
Published: May 2009

Surfing gold and silica! A new cholesterol‐based tether was attached to both amine‐functionalised silica and gold surfaces. The resultant self‐assembled monolayers, which can be deep‐UV‐patterned, were used in attaching essentially equivalent patterned supported lipid bilayers both on silica for fluorescence studies (left figure) and on gold for impedance studies (right figure).

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We report a new cholesterol‐based self‐assembled monolayer (SAM) for use in attaching lipid membranes to both gold and silica surfaces that can be patterned by deep UV (254 nm) photolysis. It allows essentially equivalent patterned supported bilayers to be created both on gold for impedance studies and on silica for fluorescence studies. On either surface an amine‐functionalised SAM is reacted with an N‐hydroxysuccinimidylcarbonyl‐functionalised EO3‐cholesteryl derivative. The formation of the amine‐functionalised SAM and its reaction with the EO3‐cholesteryl derivative were followed by contact‐angle measurements, ellipsometry and X‐ray photoelectron spectroscopy. The resultant layer of cholesterol tethers was patterned by deep UV photolysis, which regenerates the original SiO2 surface in exposed regions on a silica substrate and oxidises thiol groups on a gold substrate. This patterned surface containing hydrophilic SiO2 (or ‐OH groups) and hydrophobic cholesterol tether regions can be converted to a surface patterned with supported lipid bi‐ and monolayers (respectively) by immersing in a solution of small unilamellar vesicles of egg yolk phosphatidycholine. The formation of the lipid bi‐ and monolayer regions on the silica surface was evidenced by fluorescence microscopy. Crucially the bilayer regions remain fully fluid yielding lipid mobilities comparable to those found in physisorbed bilayers. Furthermore charged fluorescent lipids are shown to migrate in an applied field thus providing a platform for the studying the electrophoresis (potentially) for a wide range of charged membrane components, such as membrane proteins. The formation of the patterned lipid membrane on the gold surface was confirmed by electrochemical impedance measurements.
Unique Twisted Ribbons Generated by Self‐Assembly of Oligo(p‐phenylene ethylene) Bearing Dimeric Bile Acid Pendant Groups
Authors: Li Yan , Li Guangtao , Wang Xinyan , Li Weina , Su Zhixiang , Zhang Yihe , Ju Yong
Published: May 2009

Let's twist again! Remarkable broad and twisted ribbons were generated from the self‐assembly of oligo(p‐ phenylene ethylene) (OPE) bearing dimeric deoxycholic acid pendant groups (see graphic). Varying the bile acid led to nanostructures with drastically different morphologies. The distinctive aggregate shapes of these steroid–OPE conjugates are attributed to the subtle differences in their molecular structures.

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A series of novel oligo(p‐phenylene ethynylene) (OPE) derivatives bearing dimeric cholic acid (OPE1), deoxycholic acid (OPE2) and lithocholic acid (OPE3) was synthesized. The self‐assembly behavior of these derivatives were systematically studied and compared in a THF/water solvent mixture. The addition of water to THF can induce the helical stacking of oligo(p‐phenylene ethylene) bearing dimeric deoxycholic acid end groups, which leads to highly interesting twisted assemblies. Variation of the bile acid group led to nanostructures with drastically different morphologies. The application of spectroscopy in combination with X‐ray diffraction techniques provided a reasonable view of the final self‐assembled structures. The observed distinctive aggregate shapes and the preference in the type of molecular packing of these steroid–OPE conjugates are attributed to the subtle differences in their molecular features.
The Supramolecular Association of Polyelectrolytes to Complementary Charged Surfactants and Protein Assemblies
Authors: Perico Angelo , Ciferri Alberto
Published: May 2009

Cohesion matters! The correlation between the conformational rigidity of the polyelectrolyte and the size and stability of the globular assembly is discussed in this review article. Some examples of models for the association of polyelectrolytes to globular assemblies are shown here.

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Supramolecular complexes of strong polyelectrolytes and oppositely charged ionic micelles or protein assemblies derive their main stabilization from electrostatic interactions that include the counterion condensation/release mechanism and from hydrophobic interactions distributed along apolar sections of the components. The predicted and the experimental behavior of selected complexes differing in the flexibility of the polyelectrolyte and in the cohesion of the complementary assembly is reviewed and analyzed. Depending upon the rigidity of the polyelectrolyte, globular surfactant clusters persist in the final structure or are transformed into elongated assemblies. On the other hand, even the rather rigid DNA molecule is forced to bend by strongly associated cationic protein complexes such as the histone octamers. A general framework should allow the prediction of these structures in terms of the interplay between the persistence length of the polyelectrolyte and the association constant of the protein or the surfactant assembly.
ChemInform Abstract: Crystal Structure of the HT‐Al3Co Phase.
Authors: Hu C. H. , Li X. Z.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Silver‐Transfer in Proustite Ag3AsS3 at High Temperatures: Conductivity and Single‐Crystal X‐Ray Studies.
Authors: Gagor Anna , Pawlowski Antoni , Pietraszko Adam
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Stable BaCeO3‐Based Proton Conductor for Intermediate‐Temperature Solid Oxide Fuel Cells.
Authors: Xie Kui , Yan Ruiqiang , Chen Xiaorui , Dong Dehua , Wang Songlin , Liu Xingqin , Meng Guangyao
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Al—B—Nb—Ti System. Part 4. Experimental Study and Thermodynamic Re‐Evaluation of the Binary Al—Nb and Ternary Al—Nb—Ti Systems.
Authors: Witusiewicz V. T. , Bondar A. A. , Hecht U. , Velikanova T. Ya.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Approach to the Synthesis of Molybdenum Phosphide via Internal Oxidation and Reduction Route.
Authors: Yao Z. W. , Wang Li , Dong Haitao
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Substituted 1,2,4‐Triazoles and Thiazolidinones from Fatty Acids: Spectral Characterization and Antimicrobial Activity.
Authors: Banday Mudasir Rashid , Rauf Abdul
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Simple and Efficient Method for Sulfonylation of Amines, Alcohols and Phenols with Cupric Oxide under Mild Conditions.
Authors: Meshram G. A. , Patil Vishvanath D.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ruthenium‐Catalyzed N‐Alkylation of Amines and Sulfonamides Using Borrowing Hydrogen Methodology.
Authors: Hamid M. Haniti S. A. , Allen C. Liana , Lamb Gareth W. , Maxwell Aoife C. , Maytum Hannah C. , Watson Andrew J. A. , Williams Jonathan M. J.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A One‐Pot Method of Conversion of Aldehydes into Nitriles Using Iodine in Ammonia Water: Synthesis of 2‐Chloro‐3‐cyanoquinolines.
Authors: Upadhyay Shraddha , Chandra Atish , Singh Radhey M.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Development of the First Iron Chloride Catalyzed Hydration of Terminal Alkynes.
Authors: Wu Xiao‐Feng , Bezier David , Darcel Christophe
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Unprecedented Cobalt‐Catalyzed Oxidative Glaser Coupling under Reductive Conditions.
Authors: Hilt Gerhard , Hengst Christoph , Arndt Marion
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium‐Catalyzed, One‐Pot, Three‐Component Synthesis of Homoallylic Amines from Aldehydes, Anisidine, and Allyl Trifluoroacetate.
Authors: Grote Robin E. , Jarvo Elizabeth R.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: An N‐Linked Bidentate Phosphoramidite Ligand (N‐Me‐BIPAM) for Rhodium‐Catalyzed Asymmetric Addition of Arylboronic Acids to N‐Sulfonylarylaldimines.
Authors: Kurihara Kazunori , Yamamoto Yasunori , Miyaura Norio
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Preparatively Convenient Ligand‐Free Catalytic PEG 2000 Suzuki—Miyaura Coupling.
Authors: Razler Thomas M. , Hsiao Yi , Qian Feng , Fu Ruiling , Khan Rana Kashif , Doubleday Wendel
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Photochemical Studies on Benzonorbornene Derivatives: Medium Effects and Asymmetric Induction.
Authors: Yang Chao , Xia Wujiong , Chen Qian , Zhang Xiao , Li Bing , Gou Baoquan
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Effect of Additives on Chemoselectivity and Diastereoselectivity in the Catalytic Epoxidation of Chiral Allylic Alcohols with Hydrogen Peroxide and Binuclear Manganese Complexes.
Authors: Kilic Hamdullah , Adam Waldemar , Alsters Paul L.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Optically Active Arylaziridines by Regio‐ and Stereospecific Lithiation of N‐Bus‐phenylaziridine.
Authors: Musio Biagia , Clarkson Guy J. , Shipman Michael , Florio Saverio , Luisi Renzo
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Iridium‐Catalyzed Asymmetric Hydrogenation of Cyclic Enamines.
Authors: Hou Guo‐Hua , Xie Jian‐Hua , Yan Pu‐Cha , Zhou Qi‐Lin
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Analgesic and Antiinflammatory Activities of Bis(indolyl)methanes.
Authors: Sujatha Kuppusamy , Perumal Paramasivan T. , Muralidharan Doraisamy , Rajendran Melani
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 2‐Oxazol‐5‐ylethanones by Consecutive Three‐Component Amidation—Coupling—Cycloisomerization (ACCI) Sequence.
Authors: Merkul Eugen , Grotkopp Oliver , Mueller Thomas J. J.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Acyloxyetherifications Mediated by Lead Tetracarboxylates.
Authors: Cottrell Ian F. , Moloney Mark G. , Smithies Kirsty
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Catalytic Prins Cyclization Leading to Oxa‐ and Azacycles.
Authors: Miranda Pedro O. , Carballo Ruben M. , Martin Victor S. , Padron Juan I.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Stereoselective Synthesis of Nipecotic Acid Derivatives via Palladium‐Catalyzed Decarboxylative Cyclization of γ‐Methylidene‐δ‐valerolactones with Imines.
Authors: Shintani Ryo , Murakami Masataka , Hayashi Tamio
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of a Novel Pentacycle: 8‐Methyl‐10‐phenylpyrazolo[4′,3′:5,6]pyrano[3,2‐c]‐ [1,10]phenanthrolin‐7(10H)‐one.
Authors: Eller G. A. , Habicht D. , Holzer W.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Tricyclic Fused 3‐Aminopyridines Through Intramolecular CoI‐Catalyzed [2 + 2 + 2] Cycloaddition Between Ynamides, Nitriles, and Alkynes.
Authors: Garcia Pierre , Moulin Solenne , Miclo Yves , Leboeuf David , Gandon Vincent , Aubert Corinne , Malacria Max
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Novel and Convenient Protocol for Synthesis of Pyridazines.
Authors: Attanasi Orazio A. , Favi Gianfranco , Filippone Paolino , Perrulli Francesca R. , Santeusanio Stefania
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Antiinflammatory and Analgesic Activity Evaluation of Some Pyrimidine Derivatives.
Authors: Sondhi Sham M. , Dinodia Monica , Rani Reshma , Shukla Rakesh , Raghubir Ram
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Unexpected Result of the Reaction of Perimidines with 1,3,5‐Triazine in the Presence of Sodium Nitrite.
Authors: Aksenova I. V. , Aksenov A. V. , Lyakhovnenko A. S.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Unexpected Result of the Reaction of 2‐Ethoxynaphthalene with 2,4,6‐Trimethyl‐1,3,5‐triazine.
Authors: Aksenov A. V. , Aksenova I. V. , Zamorkin A. A.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: ortho‐Lithiophenyl Isocyanide: A Versatile Precursor for 3H‐Quinazolin‐4‐ones and 3H‐Quinazolin‐4‐thiones.
Authors: Lygin Alexander V. , de Meijere Armin
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of C2‐Symmetric Glycophanes Through a “Click Chemistry” Approach
Authors: Balou Gildas R. , Joly Jean‐Pierre , Vernex‐Loset Lionel , Chapleur Yves
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A Bianthraquinone and Anthraquinone from Cassia javanica Heart Wood.
Authors: Singh Supriya , Singh Janhavi
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Balticols A—F, New Naphthalenone Derivatives with Antiviral Activity, from an Ascomycetous Fungus.
Authors: Shushni Muftah A. M. , Mentel Renate , Lindequist Ulrike , Jansen Rolf
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Cytotoxic Properties of Derivatives of the tert‐Butyl Ester of 7‐Alkylidene‐3‐methyl‐3‐cepheme‐4‐carboxylic Acid.
Authors: Vorona M. , Potorocina I. , Veinberg G. , Shestakova I. , Kanepe I. , Lukevics E.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mutactimycin E, a New Anthracycline Antibiotic with Gram‐Positive Activity.
Authors: Mocek Ulla , et al. et al.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Rapid Detection of Melamine in Untreated Milk and Wheat Gluten by Ultrasound‐Assisted Extractive Electrospray Ionization Mass Spectrometry (EESI‐MS).
Authors: Zhu Liang , Gamez Gerardo , Chen Huanwen , Chingin Konstantin , Zenobi Renato
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Weakly Bound Molecules in the Atmosphere: A Case Study of HOOO
Authors: Murray Craig , Derro Erika L. , Sechler Timothy D. , Lester Marsha I.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: From Ionic Liquids to Supramolecular Polymers.
Authors: Craig Stephen L.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Amaryllidaceae and Sceletium Alkaloids
Authors: Jin Zhong
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Muscarine, Imidazole, Oxazole and Thiazole Alkaloids
Authors: Jin Zhong
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Therapeutic Applications of Glycosidic Carbonic Anhydrase Inhibitors
Authors: Winum Jean‐Yves , Poulsen Sally‐Ann , Supuran Claudiu T.
Published: May 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Numerical modelling and simulation of pulverized solid‐fuel combustion in swirl burners
Authors: Ettouati H. , Boutoub A. , Benticha H. , Sassi M.
Published: May 2009

A finite‐volume numerical model for computer simulation of pulverized solid‐fuel combustion in furnaces with axisymmetric‐geometry swirl burner is presented. The simulation model is based on the k − ε single phase turbulence model, considering the presence of the dispersed solid phase via additional source terms in the gas phase equations. The dispersed phase is treated by the particle source in cell (PSIC) method. Solid fuel particle devolatilization, homogenous and heterogeneous chemical reaction processes are modelled via a global combustion model. The radiative heat transfer equation is also resolved using the finite volume method. The numerical simulation code is validated by comparing computational and experimental results of pulverized coal in an experimental furnace equipped with a swirl burner. It is shown that the developed numerical code can successfully predict the flow field and flame structure including swirl effects and can therefore be used for the design and optimization of pulverized solid‐fuel swirl burners.
Improving flowability of cohesive particles by partial coating on the surfaces
Authors: Xu Chunbao Charles , Zhang Hui , Zhu Jesse
Published: May 2009

Very fine guest particles were partially coated onto the surfaces of cohesive particles using a patent‐pending dry particle coating method involving shear force. It was observed that partial coating on the surfaces could significantly reduce the cohesiveness and hence enhance the flowability of cohesive host particles. Based on different contacting status of the guest particles in relation to the host particles, two contact models were proposed. Inter‐particle forces based on these models were employed to discuss the possible roles of the guest particles, partially coated on the host particle surfaces, in reducing the cohesiveness of the host particles.
Dynamics of bacterial cytoskeletal elements
Authors: Graumann Peter L.
Published: May 2009

Bacterial cytoskeletal elements are involved in an astonishing spectrum of cellular functions, from cell shape determination to cell division, plasmid segregation, the positioning of membrane‐associated proteins and membrane structures, and other aspects of bacterial physiology. Interestingly, these functions are not necessarily conserved, neither between different bacterial species nor between bacteria and eukaryotic cells. The flexibility of cytoskeletal elements in performing different tasks is amazing and emphasises their very early development during evolution. This review focuses on the dynamics of cytoskeletal elements from bacteria. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Identification and cell cycle‐dependent localization of nine novel, genuine centrosomal components in Dictyostelium discoideum
Authors: Schulz Irene , Erle Alexander , Gräf Ralph , Krüger Anne , Lohmeier Heiner , Putzler Sascha , Samereier Matthias , Weidenthaler Sebastian
Published: May 2009

The centrosome is the main microtubule‐organizing center and constitutes the largest protein complex in a eukaryotic cell. The Dictyostelium centrosome is an established model for acentriolar centrosomes and it consists of a layered core structure surrounded by a so‐called corona, which harbors microtubule nucleation complexes. We have identified 34 new centrosomal candidate proteins through mass spectrometrical analysis of the proteome of isolated Dictyostelium centrosomes. Here we present a characterization of 12 centrosomal candidate proteins all featuring coiled coil regions and low expression levels, which are the most common attributes of centrosomal proteins. We used GFP fusion proteins to localize the candidate proteins in whole cells and on microtubule‐free, isolated centrosomes. Thus we were able to identify nine new genuine centrosomal proteins including a putative orthologue of Cep192, an interaction partner of polo‐like kinase 4 in human centriole biogenesis. In this respect, centrosomal localization of the only polo‐like kinase in Dictyostelium, Plk, is also shown in this work. Using confocal deconvolution microscopy, four components, CP39, CP55, CP75, and CP91 could be clearly assigned to the so far almost uncharacterized centrosomal core structure, while CP148 and Cep192 localized to a zone between that of corona marker and core proteins. Finally, CP103 and CP248 were constituents of the corona. In contrast, NE81 was localized at the nuclear envelope and three others, an orthologue of the spindle checkpoint component Mad1, the novel Cenp68, and the centrosomal CP248 were observed at the centromeres, which are clustered and linked to the centrosome throughout the entire cell cycle. Cell Motil. Cytoskeleton 66: 915–928, 2009. © 2009 Wiley‐Liss, Inc.
Truncation and Optimisation of Peptide Inhibitors of Cyclin‐Dependent Kinase 2‐Cyclin A Through Structure‐Guided Design
Authors: Kontopidis George , Andrews Martin J. , McInnes Campbell , Plater Andy , Innes Lorraine , Renachowski Scott , Cowan Angela , Fischer Peter M.
Published: May 2009

Peptides that inhibit cyclin‐dependent kinase 2 by blocking the macromolecular substrate recruitment site of cyclin A were simplified, for example, by replacement of dipeptide units with β‐amino acids. The smallest inhibitor retaining activity was a tripeptide, whose binding mode was confirmed by X‐ray crystallography. This result suggests that nonpeptidic cyclin groove inhibitors may be feasible therapeutic agents.

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The cyclin‐dependent kinase 2–cyclin A complex is an important regulator of the DNA‐synthesis phase of the mammalian cell cycle, which is frequently deregulated in cancer. Rather than blocking the ATP‐binding site of the apparently redundant kinase subunit, targeting the binding site for macromolecular substrates and regulatory proteins of cyclin A represents a promising strategy to enforce tumour‐selective apoptosis. The cyclin‐binding groove can be blocked with comparatively small synthetic peptides, which indirectly leads to inhibition of kinase function, but these peptides are metabolically labile and membrane impermeable. As part of our ongoing effort to develop more druglike peptidomimetics derived from cyclin‐groove‐binding peptides, we report the results of our studies aimed at a detailed understanding of the structural determinants required for effective binding. Using a combination of peptide synthesis, biochemical assays and X‐ray crystallography, we show that it is possible to simplify peptide structures through the replacement of dipeptide units in which one of the residues is not directly involved in binding, through the introduction of β‐amino acid residues that retain only the dipeptide residue side chain that is important for binding. This approach also allowed us to probe spatial constraints in general, as well as the importance of peptide backbone hydrogen‐bonding functions. Our identification of potent β‐homoleucine‐containing tetrapeptide inhibitors, as well as the finding that an optimised N‐terminally acetylated tripeptide retains some cyclin A‐binding affinity, suggest that the pharmacological targeting of the cyclin A binding groove may be feasible.
Intraepithelial T cells and tumor proliferation
Authors: Adams Sarah F. , Levine Douglas A. , Cadungog Mark G. , Hammond Rachel , Facciabene Andrea , Olvera Narciso , Rubin Stephen C. , Boyd Jeff , Gimotty Phyllis A. , Coukos George
Published: May 2009

BACKGROUND:

The aim of the study was to determine whether tumor‐infiltrating lymphocytes and/or tumor mitotic activity could identify subgroups of patients with advanced serous epithelial ovarian cancer who would maximally benefit from aggressive surgical cytoreduction.

METHODS:

Snap‐frozen specimens from 134 consecutive patients with stage III or IV serous or poorly differentiated ovarian adenocarcinoma undergoing primary debulking surgery from a single US institution were characterized based on CD3+, CD8+, FoxP3+ tumor‐infiltrating lymphocytes, and Ki67 expression. Kaplan‐Meier survival curves were estimated and compared using a log‐rank statistic. A multivariate Cox model was used to estimate adjusted hazard ratios. Interactions were modeled using recursive partitioning based on maximal prognostic differentiation.

RESULTS:

Brisk intraepithelial CD8+ cells (P = .035) and low Ki67 expression (P = .042) portended prolonged survival. The T‐cell infiltration was more likely to occur in tumors with high proliferation index. Patients whose tumors exhibited low Ki67 expression and high intraepithelial CD8+ frequency had a 5‐year survival rate of 73.3%. Patients with aggressive tumor behavior, that is, whose tumors exhibited low frequency of intraepithelial CD8+ T cells or high Ki67 expression were more likely to draw benefit from aggressive surgical cytoreduction. Survival was similar for patients with brisk CD8+ T cells who had optimal or suboptimal debulking. Likewise, survival was similar for patients with low Ki67 expression who had optimal or suboptimal debulking.

CONCLUSIONS:

For the first time, these novel interactions of T cells, tumor proliferation index, and surgical treatment reveal that biological prognosticators may be useful for surgical decision making in ovarian cancer. Cancer 2009. © 2009 American Cancer Society.
So‐called “malignant blue nevus”
Authors: Martin Richard C. W. , Murali Rajmohan , Scolyer Richard A. , Fitzgerald Patrick , Colman Marjorie H. , Thompson John F.
Published: May 2009

BACKGROUND:

Melanomas that arise in association with or that resemble blue nevi are extremely rare and have been termed “malignant blue nevi.” The authors report on a single‐institutional clinicopathologic study of “blue nevus‐like melanomas” (BNLMs).

METHODS:

Twenty‐six patients were identified with a “malignant blue nevus” over 29 years at the Sydney Melanoma Unit. Twenty‐three patients were included in the current study after pathologic review. Clinical outcomes of those patients were compared with the outcomes in a matched control group of patients with melanoma (matched for age, sex, Breslow thickness, Clark level, ulceration, and anatomic site).

RESULTS:

The median patient age was 44 years, and men comprised 65% of the patients. The tumors were distributed evenly among skin sites, and their median Breslow thickness was 5.5 mm. After a median follow‐up of 36.5 months, there was no difference in survival (P = .702) between patients with BNLM and patients in the control group.

CONCLUSIONS:

BNLMs tended to present at a more advanced stage, with thicker primary tumors, but had a metastatic pattern comparable to and was not more aggressive in behavior than other types of melanoma. The authors concluded that BNLMs should be treated in the same way as any other melanoma variants based on clinical staging and pathologic prognostic indices. Cancer 2009. © 2009 American Cancer Society.