bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Enantioselective Organocatalytic Phospha‐Michael Reaction of α,β‐Unsaturated Ketones.
Authors: Wen Shigang , Li Pengfei , Wu Haibo , Yu Feng , Liang Xinmiao , Ye Jinxing 
Published: October 2010

AbstractAn epiquinine‐derived urea demonstrates good catalytic activity in the enantioselective phospha‐Michael addition of diaryl phosphine oxides (II) to unsaturated ketones.
ChemInform Abstract: Synthesis and Biological Evaluation of Novel Spiro 6‐Methoxytetralin‐1,3′‐pyrrolidine Based Organoselenocyanates Against Cadmium‐Induced Oxidative and Hepatic Damage in Mice.
Authors: Sk Ugir Hossain , Sharma Arun K. , Ghosh Sulekha , Bhattacharya Sudin 
Published: October 2010

AbstractThe procedure adopted for the synthesis of selenocyanates (X) involves the construction of the pyrrolidine moiety by the intramolecular cyclization of dinitrile (V).
ChemInform Abstract: Reaction of Thiocamphor with Disulfur Dichloride: Novel Formation of α‐Disulfine.
Authors: Okuma Kentaro , Tsubota Toshiaki , Tabuchi Miki , Kanto Masayuki , Nagahora Noriyoshi , Shioji Kosei , Yokomori Yoshinobu 
Published: October 2010

AbstractReaction of thiocamphor (I) with disulfur dichloride affords six‐ and seven‐membered tricyclic polysulfanes (II) and (III), respectively, which are oxidized by MCPBA to give bicyclic (E,E)‐α‐disulfine (IV) stereoselectively.
ChemInform Abstract: Two New Verticillane‐Type Diterpenoids from the Formosan Soft Coral Cespitularia hypotentaculata
Authors: Cheng Shi‐Yie , Lin En‐Hung , Wen Zhi‐Hong , Chiang Michael Yen‐Nan , Duh Chang‐Yih 
Published: October 2010

Abstractisolation, structure determination and antiinflammatory activity of cespitularins R (I) and S (II) along with seven known compounds
ChemInform Abstract: Chemical Constituents from the Leaves and Stems of Schisandra lancifolia.
Authors: Xiao Wei‐Lie , Yang Liu‐Meng , Zhang Hai‐Bo , Xue Yong‐Bo , Yang Guang‐Yu , Pu Jian‐Xin , Wang Rui‐Rui , Zheng Yong‐Tang , Sun Han‐Dong 
Published: October 2010

AbstractThe new nortriterpenoid, 20‐hydroxymicrandilactone D (I), and the novel lignan glycoside, lancilignanside A (II) are isolated from the leaves and stems of Schisandra lancifolia along with three known nortriterpenoids and nine known phenolics.
ChemInform Abstract: Synthesis and QSAR Studies of 16‐(3‐Methoxy‐4‐substituted benzylidene) Androstene Derivatives as Anticancer Agents.
Authors: Dubey Sonal , Kaur Parmeet , Jindal Dharam Paul , Satyanarayan Yalamanchili Darji , Piplani Poonam 
Published: October 2010

AbstractA variety of substituted androstene derivatives is synthesized and evaluated for their antineoplastic activity against a panel of three human cell lines.
ChemInform Abstract: Polyhydroxy Steroids and Saponins from China Sea Starfish Asterina pectinifera and Their Biological Activities
Authors: Liu Yonghong , et al. et al. 
Published: October 2010

Abstractisolation of the new polyhydroxy sterol ester (I) along with seven known steroid derivatives and evaluation for their antiviral activity against herpes simplex virus type 1 and their cytotoxicity against human liver carcinoma HepG2 cell line in vitro
ChemInform Abstract: First Synthesis and Antiprotozoal Activities of Divinyl Sulfone‐Modified Carbohydrates.
Authors: Pal Tarun Kumar , Dey Tuli , Chakrabarty Arindam , Dey Debanjana , Ghosh Sudip K. , Pathak Tanmaya 
Published: October 2010

AbstractCarbohydrate epoxides (I) react with mercaptoethanol (II) in a regiospecific fashion to afford the sulfides (III) which upon oxidation, mesylation, and elimination are converted into vinyl sulfones (V).
ChemInform Abstract: Selective Oxidation of Glycosyl Sulfides to Sulfoxides with Sodium Hypochlorite and Catalyzed by Metalloporphyrins.
Authors: Huang Jian‐Ying , Li Shi‐Jun , Wang Yan‐Guang 
Published: October 2010

AbstractThe oxidation of glycosyl sulfides to the corresponding glycosyl sulfoxides is carried out using metalloporphyrins as catalysts.
ChemInform Abstract: Quinlobelane: A Water‐Soluble Lobelane Analogue and Inhibitor of VMAT2.
Authors: Vartak Ashish P. , Deaciuc A. Gabriela , Dwoskin Linda P. , Crooks Peter A. 
Published: October 2010

AbstractThe analogues (IV) of lobelane are synthesized by replacing its phenyl groups with either pyridyl, indolyl, or quinolyl groups.
ChemInform Abstract: Efficient Synthesis of Galactosylceramide Analogues for iNKT Cell Stimulation.
Authors: Chen Wenlan , Xia Chengfeng , Cai Li , Wang Peng George 
Published: October 2010

AbstractAn efficient synthesis of galactosylceramide analogues of type (VIII) for invariant natural killer T (iNKT) cell stimulation is described.
ChemInform Abstract: Fast [3 + 2] Cycloaddition Synthesis of (.+‐.) Pterocarpans under Microwave Irradiation.
Authors: Ventura Claiton P. , Viana Iara Maira de O. , Ferreira Eruzia A. E. , de Freitas Rossimiriam P. , Alves Rosemeire B. 
Published: October 2010

AbstractPerforming the title reaction under microwave irradiation allows significant yield enhancement and reduction of reaction time when compared to traditional methods.
ChemInform Abstract: Phenolic Constituents from Brainea insignis
Authors: Wang Kou , Li Ming‐Ming , Chen Xuan‐Qin , Peng Li‐Yan , Cheng Xiao , Li Yan , Zhao Qin‐Shi 
Published: October 2010

Abstractisolation, structure and cytotoxicity of brainicin (I), an unusual flavanol coupled with phenylpropyl and shikimic acid units, and new flavonol acylglycoside brainoside B (II) along with 14 known phenolic compounds
ChemInform Abstract: Inhibition of ABCG2‐Mediated Drug Efflux by Naphthopyrones from Marine Crinoids.
Authors: Bokesch Heidi R. , Cartner Laura K. , Fuller Richard W. , Wilson Jennifer A. , Henrich Curtis J. , Kelley James A. , Gustafson Kirk R. , McMahon James B. , McKee Tawnya C. 
Published: October 2010

AbstractFive new naphthopyrones of type (I) or (II) are isolated from crinoids of the family Comasteridae along with 6 known compounds.
ChemInform Abstract: Enantioselective Syntheses of the Proposed Structures of Cytotoxic Macrolides Iriomoteolide‐1a (I) and ‐1b (II).
Authors: Ghosh Arun K. , Yuan Hao 
Published: October 2010

AbstractThe NMR data of synthetic (I) and (II) differ from those of the natural products.
ChemInform Abstract: Enantioselective Synthesis of a Diastereomer of Iriomoteolide‐1a. What Is the Correct Structure of the Natural Product?
Authors: Fang Lijing , Yang Jiong , Yang Fei 
Published: October 2010

AbstractComparison of the NMR data of the synthetic product with those of the natural substance reveals that (I) is epimeric at one or more stereocenters.
ChemInform Abstract: Synthesis of Carbon Nanorods by Reduction of Carbon Bisulfide.
Authors: Lou Zhengsong , He Minglong , Zhao Dejian , Li Zhongchun , Shang Tongming 
Published: October 2010

AbstractCarbon nanorods are prepared at large scale from CS2 and metallic Li (autoclave, 600 °C, 10 h, yield given in g) and characterized by powder XRD, SEM, TEM, and N2 physisorption.
ChemInform Abstract: Controlled Synthesis of Urchin‐Like Bi2S3 via Hydrothermal Method.
Authors: Tang Chunjuan , Wang Changqing , Su Fengjian , Zang Chunhe , Yang Yanxin , Zong Zhengjun , Zhang Yongsheng 
Published: October 2010

AbstractSpherical urchin‐like Bi2S3 flowers consisting of porous nanorods, solid nanorods, or nanowires which grow radially from the center of the nanostructures toward all directions are hydrothermally prepared from aqueous solutions of thiourea and Bi(NO3)3 (autoclave, 140 °C, 0.5—12 h).
ChemInform Abstract: Synthesis of Novel β‐Carbolines with Efficient DNA‐Binding Capacity and Potent Cytotoxicity.
Authors: Chen Zhiyong , Cao Rihui , Shi Buxi , Yi Wei , Yu Liang , Song Huacan , Ren Zhenhua , Peng Wenlie 
Published: October 2010

Abstract19 novel β‐carbolines of type (I) with efficient DNA‐binding capacity and potent cytotoxicity are prepared.
Expression of the transcription factor Olig2 in proliferating cells in the adult zebrafish telencephalon
Authors: März Martin , Schmidt Rebecca , Rastegar Sepand , Strähle Uwe 
Published: October 2010

AbstractThe telencephalon of the adult zebrafish is highly proliferative: Dividing cells are found along the entire ventricular zone and in the parenchyma. Here, we investigated the relation of proliferating cells in the telencephalic parenchyma to the oligodendrocyte lineage. We find at least three different cell types of the oligodendrocyte lineage (olig2‐and sox10‐positive) in the parenchyma of the telencephalon: Proliferating progenitors (PCNA‐positive), including a subpopulation of slowly dividing progenitors (long term label‐retaining), as well as mature oligodendrocytes (Mbp‐positive) and presumptive quiescent OPCs (neither Mbp‐positive nor proliferating). Furthermore, in the ventricular zone (in and ventral to the RMS), two different subpopulations of olig2‐positive cell populations are present. Since these ventricular olig2‐positive cells do not express the oligodendrocyte marker sox10, it is not clear whether these cells indeed belong to the oligodendrocyte lineage. Taken together, we detected at least five different classes of olig2‐positive cells in the telencephalon of the adult zebrafish. Developmental Dynamics 239:3336–3349, 2010. © 2010 Wiley‐Liss, Inc.
Embryonic coronary vasculogenesis and angiogenesis are regulated by interactions between multiple FGFs and VEGF and are influenced by mesenchymal stem cells
Authors: Tomanek Robert J. , Christensen Lance P. , Simons Michael , Murakami Masahiro , Zheng Wei , Schatteman Gina C. 
Published: October 2010

AbstractIn embryonic hearts explanted on collagen gels, epicardial cells delaminate and form vascular tubes, thus providing a model for coronary tubulogenesis. Using this model, we show that fibroblast growth factors (FGFs) 1, 2, 4, 8, 9, and 18 contribute to tubulogenesis and that the availability of multiple FGFs provides the optimal tubulogenic response. Moreover, the FGF effects are vascular endothelial growth factor (VEGF) ‐dependent, while VEGF‐induced tubulogenesis requires FGF signaling. The number of endothelial cells (ECs) is increased by all of the FGFs, while EC migration is significantly enhanced only by FGF‐2 and FGF‐18. Finally, addition of embryonic mesenchymal stem cells (EMSC) to the explants markedly enhances EC numbers and a 23‐fold increase in stromal derived factor‐1α (SDF‐1α), which is FGF dependent. Both explants and EMSCs produce SDF‐1α. In conclusion, coronary tubulogenesis of embryonic epicardium: (1) is responsive to many FGF family members, (2) requires both FGF and VEGFA signaling, and (3) is responsive to EMSCs. Developmental Dynamics 239:3182–3191, 2010. © 2010 Wiley‐Liss, Inc.
The dual histone demethylase KDM7A promotes neural induction in early chick embryos
Authors: Huang Chengyang , Chen Jun , Zhang Ting , Zhu Qingqing , Xiang Yang , Chen Charlie Degui , Jing Naihe 
Published: October 2010

AbstractNeural induction is the initial event of nervous system development during which part of the ectoderm is specified to become the embryonic neural plate. The biological roles of histone modification enzymes in the neural induction of early embryos remain unclear. Here, we show that an evolutionarily conserved dual histone demethylase KDM7A (KIAA1718) is predominantly expressed in epiblast cells of the primitive streak in early chick embryos. Overexpression of KDM7A in chick embryos leads to expansion of the neural plate, whereas knockdown of the gene impairs formation of the neural plate. We also show that KDM7A regulates Fgf4 expression in the primitive streak and that co‐electroporation of a chick Fgf4 expression vector with KDM7A siRNA rescues the neural induction defect in chick embryos. Taken together, these results reveal an important role for histone demethylases in the determination of neural fate, and they highlight the mechanistic complexity of neural induction in early embryos. Developmental Dynamics 239:3350–3357, 2010. © 2010 Wiley‐Liss, Inc.
GPR56 is essential for testis development and male fertility in mice
Authors: Chen Guangchun , Yang Liquan , Begum Shahinoor , Xu Lei 
Published: October 2010

AbstractTestis development is critical for male fertility and continuation of the mammalian species. Essential structural components of testes are seminiferous tubules, which are lined by Sertoli cells and provide nutrients and physical protection for the maturation of sperm. Seminiferous tubule formation is initiated in embryos as testis cords and relies on their remodeling for maturation during development. Recently, three‐dimensional image analyses showed that testis cords in different parts of embryonic gonads undergo distinct remodeling processes. How this asymmetric remodeling is regulated has not been investigated. We report here that the absence of an adhesion G protein‐coupled receptor, GPR56, leads to partial disruption of seminiferous tubules and reduced fertility in male mice. The defects appear to originate asymmetrically in embryonic gonads, but subsequent to the initial establishment of testis cords, suggesting that GPR56 might act to establish a spatial and/or temporal cue for asymmetric cord remodeling during male gonad development. Developmental Dynamics 239:3358–3367, 2010. © 2010 Wiley‐Liss, Inc.
Nonbonded Interactions Tune Selectivities in Cycloadditions to 2,3‐Dioxabicyclo[2.2.2]oct‐5‐ene
Authors: Quadrelli Paolo , Romano Silvano , Caramella Pierluigi 
Published: October 2010

AbstractThe facial selectivity of 2,3‐dioxabicyclo[2.2.2]oct‐5‐ene in cycloaddition reactions is distressingly variable and akin to that of 2‐oxa‐3‐azabicyclo[2.2.2]oct‐5‐ene derivatives. Osmilation takes place on the face anti to the dihetero bridge, while cycloaddition of butadiene affords exclusively the syn cycloadduct. Nitrile oxides add unselectively. B3LYP/LANL2DZ calculations of cycloadditions to 2,3‐dioxabicyclo[2.2.2]oct‐5‐ene reproduce well the experimental selectivities and give insights into the origin of the changes. The double bonds of the olefins are moderately pyramidalized toward the anti space, implying a preferred anti addition. This natural predisposition to anti addition is tuned by the mutual interaction between the addends. On going from osmilation to nitrile oxide and butadiene cycloadditions, the steric effects between the addend and the dimethylene bridge of theolefin increase remarkably and affect the attacking angle Θ and the tilting angle α of the anti addition, enforcing enhanced deformations of the olefin, which almost offset itsnatural anti predisposition. In the case of butadiene, the residual part of the steric effect increases further the anti barrier leading to a neat reversal of selectivity. 2,3‐Dioxabicyclo[2.2.1]hept‐5‐ene shows a larger anti pyramidalization, which is akin to that of norbornene itself and to 2‐oxa‐3‐azabicyclo[2.2.1]hept‐5‐ene derivatives, and mutual steric interactions have only a subordinate influence on selectivity.
Isolation and Racemization Mechanism of Optically Active Benzylmethylphenyltelluronium Salts
Authors: Shimizu Toshio , Sakurai Ryuuya , Azami Yoko , Hirabayashi Kazunori , Kamigata Nobumasa 
Published: October 2010

AbstractDiastereomeric benzylmethylphenyltelluronium (1S)‐(+)‐ and (1R)‐(–)‐camphor‐10‐sulfonates were synthesized and resolved by fractional recrystallization. The absolute configurations of the isomers were determined by X‐ray crystallographic analysis. Enantiomerically pure telluronium salts with achiral counteranions, such as tetrafluoroborate, 4‐chlorobenzenesulfonate, bromide, iodide, and tetraphenylborate, were also obtained by anion‐exchange reactions of the separated diastereomers. The optically active telluronium salts possessing counteranions with a high nucleophilicity, such as bromide and iodide, were found to racemize in solution. The racemization of the telluronium salts was found to proceed either through the formation of a tellurane by the nucleophilic addition of a counteranion to the tellurium atom followed by decomposition into methyl phenyl telluride and benzyl halide or by several pseudorotations of the tellurane.
Synthesis of the Macrolactone of Migrastatin and Analogues with Potent Cell‐Migration Inhibitory Activity
Authors: Dias Luiz C. , Finelli Fernanda G. , Conegero Leila S. , Krogh Renata , Andricopulo Adriano D. 
Published: October 2010

AbstractThe synthesis of the macrolactone core of migrastatin 2, its potent anti‐metastasis analogue 34, and ester derivatives 35 and 38 are reported. The approach involves the use of a dihydroxylation reaction to establish the desired C‐8 stereocenter followed by a metathesis cyclization reaction. The effects of the compounds on the migration and invasion of human breast cancer cells were evaluated by using the wound‐healing and the Boyden‐chamber cell‐migration and cell‐invasion assays. The results revealed a high potency of the macrolactones 2 and 34 and the ester analogues 35 and 38, which suggests they have potential as antimetastatic agents.
Synthesis of Novel Nonproteinogenic Amino Acids: N‐Ethyl‐α,β‐dehydroamino Acid Methyl Esters
Authors: Monteiro Luís S. , Kołomańska Joanna , Suarez Ana C. 
Published: October 2010

AbstractTwo routes for the synthesis of N‐ethyl‐N‐(4‐nitrophenylsulfonyl)‐α,β‐dehydroamino acid derivatives from serine, threonine and phenylserine derivatives are presented. One route consists of dehydration of N‐(4‐nitrophenylsulfonyl)‐β‐hydroxyamino acid esters with di‐tert‐butyl dicarbonate catalyzed by 4‐(dimethylamino)pyridine, followed by alkylation of the N‐(4‐nitrophenylsulfonyl)‐α,β‐dehydroamino acid methyl esters obtained with triethyloxonium tetrafluoroborate. The second strategy applied the same procedures but in inverse order: alkylation followed by dehydration. These methods made it possible to obtain for the first time, new non‐natural amino acids, which incorporate both an N‐ethyl and an α,β‐dehydro moiety.
A simple method for large‐scale generation of dopamine neurons from human embryonic stem cells
Authors: Morizane Asuka , Darsalia Vladimer , Guloglu M. Oktar , Hjalt Tord , Carta Manolo , Li Jia‐Yi , Brundin Patrik 
Published: October 2010

AbstractDopamine (DA) neurons derived from human embryonic stem cells (hESCs) are potentially valuable in drug screening and as a possible source of donor tissue for transplantation in Parkinson's disease. However, existing culture protocols that promote the differentiation of DA neurons from hESCs are complex, involving multiple steps and having unreliable results between cultures. Here we report a simple and highly reproducible culture protocol that induces expandable DA neuron progenitors from hESCs in attached cultures. We found that the hESC‐derived neuronal progenitors retain their full capacity to generate DA neurons after repeated passaging in the presence of basic fibroblast growth factor (bFGF) and medium conditioned with PA6 stromal cells. Using immunocytochemistry and RT‐PCR, we found that the differentiated DA neurons exhibit a midbrain phenotype and express, e.g., Aldh1a, Ptx3, Nurr1, and Lmx1a. Using HPLC, we monitored their production of DA. We then demonstrated that the expanded progenitors are possible to cryopreserve without loosing the dopaminergic phenotype. With our protocol, we obtained large and homogeneous populations of dopaminergic progenitors and neurons. We conclude that our protocol can be used to generate human DA neurons suitable for the study of disease mechanisms, toxicology, drug screening, and intracerebral transplantation. © 2010 Wiley‐Liss, Inc.
Nanomechanik des Lebens zum Anfassen. Spiele mit Gummibändern
Authors: Euler Manfred 
Published: October 2010

AbstractErstaunlicherweise spielt die Mechanik eine große Rolle bei lebenswichtigen Funktionen biologischer Makromoleküle. Das gilt besonders für die DNS. Dort aktivieren oder inaktivieren bei der genetischen Regulation mechanische Formänderungen die Gene. Diese Nanomechanik ist bei den Zellen höher entwickelter Lebewesen der Schlüssel zur kompakten Faltung der DNS‐Stränge. Erst so passen diese in den vergleichsweise kleinen Zellkern. Beim Auslesen genetischer Information können mehrere offene Schleifen an verschiedenen Stellen der DNS miteinander in Kontakt kommen. Das macht diesen Vorgang komplexer als früher gedacht. Über die Mechanik der Faltungen kann sogar epigenetische Information ins Spiel kommen. Die Physik dieser Nanomechanik lässt sich in einfachen Gummiband‐Experimenten überraschend gut nachspielen.
Intelligent umgarnt. Textile Sensorik
Authors: Ehrmann Andrea , Flacke Eva , Brücken Andrea , Büsgen Alexander 
Published: October 2010

AbstractSensorische Textilien können beispielsweise zur Messung der Körpertemperatur, der Atmung oder eines Elektrokardiogramms genutzt werden. In einem Forschungsprojekt wird derzeit ein solches Shirt für Feuerwehrleute entwickelt, um deren Körperfunktionen im gefährlichen Einsatz zu überwachen. Generell ist es eine große Herausforderung, die leitfähigen Garne, die zu textilen Sensorflächen verarbeitet oder auch als Datenleiter genutzt werden, so nachzubehandeln, dass sie im alltäglichen Gebrauch und beim Waschen nicht beschädigt werden. Wenn dies gelingt, eröffnet die textile Sensorik neue Möglichkeiten, Kleidung und andere Textilien “intelligent” zu machen.
Vom Stokes‐Integral zum Finanzmarkt. Einführung in die Makro‐Ökonophysik
Authors: Mimkes Jürgen 
Published: October 2010

AbstractIn der Ökonomie lassen sich viele Funktionen wie Gewinn oder Einkommen nicht von vornherein berechnen. Diese “weichen” Funktionen heißen Putty (Lehm) und lassen sich durch Stokes‐Integrale darstellen. Die Anwendung dieser Integrale auf den modernen Wirtschaftskreislauf nach Irving Fisher führt auf zwei Hauptsätze der Ökonomie, die denen der Thermodynamik äquivalent sind. Mit ihnen lassen sich die Mechanismen von Produktion, Handel, Wirtschaftskreislauf, Geldkreislauf, Wachstum, Finanzmärkte und Finanzkrisen modellieren.
Blick ins Molekül
Authors: Temirov Ruslan , Tautz Stefan 
Published: October 2010

AbstractDie Erfindung des Rastertunnelmikroskops im Jahre 1981 hat die Oberflächenforschung revolutioniert und darüber hinaus einen wichtigen Beitrag zur Entstehung der Nanotechnologie geleistet. Erstmals war es möglich, atomare Strukturen direkt sichtbar zu machen. Durch eine einfache Modifikation des Tunnelkontakts kann die Auflösung eines Rastertunnelmikroskops noch dramatisch verbessert werden, wie unsere Gruppe im Forschungszentrum Jülich kürzlich zeigen konnte.
Die Unendlichkeit ist grün
Authors: Schlichting H. Joachim 
Published: October 2010

AbstractEin beliebtes Phänobjekt in Science Centern ist der Unendlichkeitsspiegel. Man blickt durch ein in der Rückwand eines Spiegels angebrachtes Loch in einen vermeintlich unendlich langen Schacht. In Wirklichkeit rufen zwei nahezu parallel und mit der Spiegelseite zueinander aufgestellte Spiegel diese Illusion hervor. Erstaunlich ist bei genauem Hinsehen, dass die Unendlichkeit grün zu sein scheint (Abbildung 1 links).
Der Pflastermathematiker
Authors: Loos Andreas 
Published: October 2010

AbstractSeit Jahrzehnten ist der Alexanderplatz das größte Betonparkett in Berlins Mitte. Im Jahre 2003 suchte der Berliner Senat Ideen für eine Neugestaltung des Platzes. Es meldeten sich damals nicht nur Architekten, sondern auch eine Gruppe von Mathematikern. Sie schlug eine quasi‐periodische Pflasterung mit Fünf‐, Sechs‐ und Siebenecken vor.