bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesen und Reaktionen 3‐C‐methylverzweigter Glycale der D‐Reihe. Darstellungen von Isomeren der endständigen Disaccharide aus Olivomycin A und Mithramycin
Authors: Thiem Joachim , Elvers Jürgen
Published: September 2007

Ausgehend von D‐Rhamnal (4) bzw. D‐Digitoxal (5) werden D‐Olivomycal (6) und D‐Mycaral (9) dargestellt. Mit der Umsetzung von 9 zu Methyl‐α‐D‐mycarosid (12) gelingt die Konfigurationszuordnung am Verzweigungspunkt. Aus der 1‐En‐3‐ulose 13 lassen sich mit Methyllithium die isomeren‐3‐C‐methylverzweigten Glycale 14 und 15 herstellen. In mehreren Stufen wird aus 14 Methyl‐3,4‐O‐carbonyl‐α‐D‐mycarosid (22) erhalten. Mit den D‐arabino‐Glycalen 7 und 15 werden auf unterschiedlichen Synthesewegen nach dem N‐Iodsuccinimid‐Verfahren Disaccharid‐Derivate dargestellt und diese in die 3′‐C‐methylverzweigten Tetradesoxydisaccharide 28 bzw. 29 übergeführt. Ferner wird entsprechend mit dem D‐ribo‐Glycal 10 das Tetradesoxydisaccharid‐Derivat 32 synthetisiert. Die Verbindungen 28 bzw. 29 und 32 sind Isomere der terminalen E–D‐ Disaccharideinheiten der Saccharid‐Cytostatica Olivomycin A bzw. Mithramycin.
Synthesis of Vinca Alkaloids and Related Compounds, XIII1) Syntheses Starting from 2‐(Ethoxycarbonyl)tryptamine
Authors: Kalaus György , Györy Péter , Kajtár‐Peredy Mária , Radics Lajos , Szabó Lajos , Szántay Csaba
Published: September 2007

The Pictet‐Spengler reaction of 2‐(ethoxycarbonyl)tryptamine (1) with aldehyde esters 2 and 3 leads to unexpected products (4a and 9a/10a, resp.). The structures of the new compounds were elucidated by spectroscopic and chemical means.
Massenspektrometrische Untersuchung von Stickstoffverbindungen, XXXI1,2) Experimentelle und theoretische Untersuchungen zur dissoziativen Ionisierung von α‐nitro‐ und α‐halogen substituierten Acetamiden. Pseudo‐einstufige Zerfallsprozesse von Radikalkationen in der Gasphase
Authors: Ciommer Bernhard , Frenking Gernot , Schwarz Helmut
Published: September 2007

Die unimolekulare Eliminierung von Br. bzw. No aus den Radikalkationen der Titelverbindungen 1 und 2 gehorcht nicht einem einstufigen Reaktionsverlauf unter Erzeugung eines substituierten α‐Acylcarbenium‐Ions 3. Markierungsexperimente und MNDO‐Rechnungen legen einen Mechanismus nahe, bei dem die Dissoziation der CX‐Bindung durch einen intramolekularen H‐Transfer von der NCH3‐ zur COGruppe eingeleitet wird. Dies führt zur Zwischenstufe 4, die schließlich zu 5 weiterzerfällt. Die mechanistischen Details der unimolekularen Zerfallsreaktionen von 5 unter Ethylen‐Verlust zu 13 und Keten‐Abspaltung zu (17) werden eingehend diskutiert.
Modelle für Excimere: Diastereomere [3.3](2,6)‐ und [3.3](1,5)(2,6)Naphthalinophane1)
Authors: Blank Norman E. , Haenel Mattsias W.
Published: September 2007

Die diastereomeren [3.3](2.6)Naphthalinophane 1, 2 und [3.3](1,5)(2,6) Naphthalinophane 3,4 wurden über die Dithia[4.4]phane 15, 17 und Dampfphasen‐Pyrolyse der Sulfone 16, 18 synthetisiert. Ihre 1H‐NMR‐ und Elektronenspektren werden im Hinblick auf Orientierung und elektronische Wechselwirkung der Naphthalin‐Sandwich‐Paare diskutiert.
Modelle für Excimere: syn‐ und anti‐[3.2](1,4) Naphthalinophane1)
Authors: Blank Norman E. , Haenel Matthias W.
Published: September 2007

Die diastereomeren syn‐ und anti‐[3.2](1,4)Naphthalinophane 1 und 2 wurden über Z. Thia 3.3J(l.4)Naphthalinophan 8 und Dampfphasen‐Pyrolyse des Sulfons 9 synthetisiert. Die Photolyse bei −23°C ergab aus 1 und 2 ihre intramolekularen [4 + 4]Cycloaddukte 15 und 14, die bei Raumtemperatur wieder zu 1 bzw. 2 rearomatisieren.
Reaktion von Tetrachlorcyclopropen mit Azid
Authors: Dehmolow Eckehard V. , Naser‐ud‐Din
Published: September 2007

Reaction between Tetrachlorocyclopropene and Azide

Tetrachlorocyclopropene (1) reacts with sodium azide to yield 1,2,3‐trichlorocyclopropenyl azide (2), a very labile product which is transformed into trichloroacrylonitrile (3) with evolution ot nitrogen.
Tosylgruppenübertragung mit O, O′‐Ditosylethylenglycol
Authors: Weber Edwin
Published: September 2007

Tosyl Group Transfer with O, O′‐Ditosylethyleneglycol

The ability of O, O′‐ditosylethyleneglycol (2a) to act as tosyl group transfer reagent to neopentyl type alcohols is described. Starting form 1a the spirooxetane 3 can be synthesized via tosyl group transfer in high yield. 4a by double tosyl transfer yields the ditosylate 4b. The homologous ditosylpropyleneglycol 2b does not react in a similar manner.
Primärprodukte bei den Photocycloadditionen von 9‐Anthracencarbonitril an α‐Terpinen und 1‐Methoxy‐1,3‐cyclohexadien
Authors: Kaupp Gerd , Schmitt Dieter
Published: September 2007

Primary Products in Photocycloadditions of 9‐Anthracenecarbonitrile to α‐Terpinene and 1‐Methoxy‐1,3‐cyclohexadiene

The title reactions proceed with high orientational selectivity according to the requirements of hybridization effects in diradical mechanisms even under the rather extreme conditions of steric hindrance and polarity involved. In competition to exciplex formation the highly hindered [4 + 2]‐ and [4 + 4]‐adducts 3, and 4 are formed via different diradicals A and B. 4 undergoes a rapid 1,3‐suprafacial shift to yield 6 at 80°C, as does 9 at 0°C to yield the enol 10 which is hydrolyzed to yield the ketone 11. The structures of the products are established primarily by high field 1H‐NMR spectroscopy.
Synthesis and Evaluation of TAC‐Based Inhibitors of Papain as Mimics of Cystatin B
Authors: van Zoelen Dirk‐Jan , Egmond Maarten R. , Pieters Roland J. , Liskamp Rob M. J.
Published: September 2007

An approach for mimicking protein–protein interactions by using a discontinuous epitope to construct a mimic that is about one tenth of the size of a natural inhibitor of papain, namely, cystatin B, is described. The discontinuous epitope of cystatin B, which is involved in the interaction with papain, was mimicked by synthesis of a tripodal molecular construct by using the triazacyclophane (TAC) scaffold. The mimic contains three peptide arms: one that mimics the N terminus, one that mimics the C terminus, and one that mimics the β‐hairpin loop structure of cystatin B. These peptide sequences were assembled on the TAC scaffold. The resulting cystatin mimic, CysTACtin 9, showed excellent inhibition of papain with a Ki of 12 nM, which approaches the inhibitory potency of cystatin B (Ki=0.12 nM). Experiments with molecular constructs that contained one or two arms or a mixture of the nonscaffolded peptides showed that both scaffolding and the presence of the three peptide arms are crucial for a successful mimic.
Effect of Modified Enzymatic Catalysis on the Extraction of Diosgenin from Dioscorea zingiberensis C. H. Wright
Authors: Zhang Y. Q. , Liang J. H. , Fu E. H. , Li B. X.
Published: September 2007

Multi‐enzymatic catalysis combined with acid hydrolysis is studied in order to enhance the efficiency of the enzymatic catalysis and reduce the mass transfer resistance from starch and cellulose in the extraction of diosgenin from Dioscorea zingiberensis C. H. Wright. The cellulase is modified by polyethylene to increase its optimal reaction temperature and pH value. The modified cellulase shows better thermostability and resistance to alkali. The modified cellulase, α‐amylase and β‐glycosidase are used to construct the multi‐enzyme and multi‐enzyme catalysis is used as a pretreatment process. Compared to primary industrial techniques including acid hydrolysis, spontaneous fermentation and enzymatic catalysis, conventional techniques are optimized by using multi‐enzymatic catalysis together with acid hydrolysis because of the higher reaction efficiency and lower levels of manipulation required. The purity of the product is more than 96 % with this technique, and the melting point is 205–207 °C. The diosgenin yield rate and the extraction rate reached are 2.43 % and 98 %, respectively. IR and 1H NMR spectroscopy were used to confirm the structure of the product.
Effects of the Inlet Section Angle on the Flow Field of a Cyclone
Authors: Qian F. P. , Zhang M. Y.
Published: September 2007

The gas flow fields of a cyclone with different inlet section angles have been studied numerically. The gas flow fields were simulated by means of the Reynolds Stress Transport Model (RSTM). The velocities and pressure drop profiles of these cyclones were investigated. The shortcut flow rates at the bottom of the vortex finder were calculated with different inlet section angles. To analyze the relationship between the inlet section angle and the vortex finder insertion deepness, this paper details the shortcut flow rates at the bottom of the vortex finder for three vortex finder insertion depths. The results indicate that the inlet section angle can decrease the shortcut flow from the bottom of the vortex finder, which has practical importance for the improvement of the separation efficiency. The inlet section angle can also decrease the pressure coefficient of a cyclone. When the inlet section angle is 45 °, the level of decrease is up to 30 %. However, the effect of the inlet section angle on the separation performance is related to the dimension of the vortex finder, i.e., the insertion depth and diameter of the vortex finder, and the effect is different when the cyclone has different vortex finder insertion depths.
A Fluorescent Molecular Switch Driven by the Input Sequence of Metal Cations: An Azamacrocyclic Ligand Containing Bipolar Anthracene Fragments
Authors: Nishimura Go , Maehara Hajime , Shiraishi Yasuhiro , Hirai Takayuki
Published: September 2007

An azamacrocyclic ligand (L) containing two anthracene (AN) fragments connected through two triethylenetetramine bridges has been synthesized, in which each of the bridges can coordinate with one metal cation. The effects of pH and metal cations (Zn2+ and Cd2+) on the emission properties of L were studied in water. Without metal cations, L does not show any emission at basic pH values. The addition of Zn2+ leads to the production of excimer emission, which is due to a static excimer formed by direct excitation of the intramolecular ground‐state dimer of the bipolar AN fragments that approach each other by Zn2+ binding. In contrast, Cd2+ addition does not result in excimer emission because the Cd2+–AN π complex, formed by donation of a π electron of the AN fragments to the adjacent Cd2+, suppresses π‐stacking interactions of the AN fragments. The most notable feature is the appearance of excimer emission controlled by the input sequence of metal cations: Zn2+→Cd2+ sequential addition (each one equivalent) allows excimer emission, whereas the reverse sequence (Cd2+→Zn2+) does not. In the Zn2+→Cd2+ sequence, Cd2+ coordination is structurally restricted by the first Zn2+ coordination with the other polyamine bridge, leading to the formation of a weak Cd2+–AN π complex. In contrast, for the reverse sequence, the first Cd2+ coordination forms a stable Cd2+–AN π complex, which is not weakened by sequential Zn2+ coordination, resulting in no excimer emission.
Total Synthesis of the Proposed Structure of the Anthrapyran Metabolite δ‐Indomycinone
Authors: Tietze Lutz F. , Singidi Ramakrishna Reddy , Gericke Kersten M.
Published: September 2007

The first total synthesis of the proposed structure of δ‐indomycinone has been accomplished. The key steps involve the Diels–Alder reaction of a bromonaphthoquinone (6) and 1‐methoxy‐3‐methyl‐1‐trimethylsiloxy‐1,3‐butadiene (7) to access the anthraquinone skeleton, representing a common building block of other naturally occurring anthraquinone antibiotics, regioselective bromination of anthraquinone (14) and a highly diastereoselective alkylation of enantiomerically pure dioxolanone 8. The reported synthetic approach has the advantage of high yields, excellent selectivity and a remarkable general applicability for the total synthesis of other anthrapyran natural products. The spectroscopic data obtained for the synthetic compounds 2 and 36 are not in agreement with those reported for the natural product, and therefore revision of the assigned structure is required.
TiIV‐Catalyzed Asymmetric Sulfenylation of 1,3‐Dicarbonyl Compounds
Authors: Jereb Marjan , Togni Antonio
Published: September 2007

The electrophilic enantioselective sulfenylation of 1,3‐dicarbonyl compounds with phenylsulfenyl chloride is effectively catalyzed by [Ti(TADDOLato)] complexes. The corresponding products are obtained in moderate to high yields. The highest ee values (up to 97 %) are obtained in toluene at room temperature and with a typical catalyst loading of 5 mol %. Bulky ester groups and sterically undemanding substituents at the α‐position were found to be crucial structural features of the starting materials in order to assure high enantioselectivity. The absolute configuration of one of the chiral products has been determined. The stereochemical course of the reaction is similar to that of analogous [Ti(TADDOLato)]‐catalyzed atom‐transfer reactions. A common side‐reaction the sulfenylated products undergo is a deacylation leading to racemic α‐sulfenylated esters.
Effects of Cu and Ti Excess on the Dielectric Properties of CaCu3Ti4O12 Prepared Using a Wet Chemical Method.
Authors: Yeoh Cheow Keat , Ahmad Mohd. Fadhli , Ahmad Zainal Arifin
Published: September 2007

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, please click on HTML or PDF.
ClnH6‐nSiGe Compounds for CMOS Compatible Semiconductor Applications: Synthesis and Fundamental Studies.
Authors: Tice Jesse B. , Chizmeshya Andrew V. G. , Roucka Radek , Tolle John , Cherry Brian R. , Kouvetakis John
Published: September 2007

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, please click on HTML or PDF.
Preparation of Cyclopenta‐Fused N‐, O‐, and S‐Heterocycles by Lewis Acid Catalyzed Nazarov Reaction.
Authors: Bartali Laura , Larini Paolo , Guarna Antonio , Occhiato Ernesto G.
Published: September 2007

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, please click on HTML or PDF.
SnCl4 and SbCl5 Promoted Aromatization of Enamines.
Authors: Bigdeli Mohammad Ali , Rahmati Abbas , Abbasi‐Ghadim Hossein , Mahdavinia Gholam Hossein
Published: September 2007

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, please click on HTML or PDF.
Mild Cobalt‐Catalyzed Hydrocyanation of Olefins with Tosyl Cyanide.
Authors: Gaspar Boris , Carreira Erick M.
Published: September 2007

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, please click on HTML or PDF.
Facile Method for Trimethylsilylation of Alcohols Using Hexamethyldisilazane and Ammonium Thiocyanate under Neutral Conditions.
Authors: Jadhav Vrushali H. , Kumar K. S. Ajish , Chaudhari Vinod D. , Dhavale Dilip D.
Published: September 2007

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, please click on HTML or PDF.
Development of Practical Rhodium Phosphine Catalysts for the Hydrogenation of β‐Dehydroamino Acid Derivatives.
Authors: Enthaler Stephan , Erre Giulia , Junge Kathrin , Holz Jens , Boerner Armin , Alberico Elisabetta , Nieddu Ilenia , Gladiali Serafino , Beller Matthias
Published: September 2007

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, please click on HTML or PDF.
Highly Enantioselective Hydrogenation of β‐Alkyl and β‐(ω‐Chloroalkyl) Substituted β‐Keto Esters.
Authors: Karame Iyad , Bellur Esen , Rotzoll Sven , Langer Peter , Fischer Christine , Holz Jens , Boerner Armin
Published: September 2007

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, please click on HTML or PDF.
Improvement of the Asymmetric Induction from Lactic Acid Derivatives Enhanced by ZnCl2.
Authors: Huettenhain Stefan H.
Published: September 2007

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, please click on HTML or PDF.
Chiral Diamides as Efficient Catalytic Precursors for the Borane‐Mediated Asymmetric Reduction of Prochiral Ketones.
Authors: Basavaiah Deevi , Rao Kalapala Venkateswara , Reddy Bhavanam Sekhara
Published: September 2007

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, please click on HTML or PDF.
The First Sequential Reaction Promoted by Manganese: Complete Stereoselective Synthesis of (E)‐α,β‐Unsaturated Esters from 2,2‐Dichloroesters and Aldehydes.
Authors: Concellon Jose M. , Rodriguez‐Solla Humberto , Diaz Pamela , Llavona Ricardo
Published: September 2007

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, please click on HTML or PDF.
Asymmetric Oxidation Catalysis by a Chiral Al(salalen) Complex: Highly Enantioselective Oxidation of Sulfides with Aqueous Hydrogen Peroxide.
Authors: Yamaguchi Tetsufumi , Matsumoto Kazuhiro , Saito Bunnai , Katsuki Tsutomu
Published: September 2007

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, please click on HTML or PDF.
Amino Acids as a Chiral Pool: Synthesis of (S)‐ and (R)‐2‐N‐Carbomethoxy‐5‐aminoindan from (S)‐ and (R)‐Phenylalanines.
Authors: Waykole Liladhar M. , McKenna Joseph J. , Bach Andrew , Prashad Mahavir , Repic Oljan , Blacklock Thomas J.
Published: September 2007

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, please click on HTML or PDF.
Sonochemical Formation of Iodohydrin and Epoxide from Cyclohexene.
Authors: Fernandes Vanessa S. , Barboza Jayne C. S. , Serra Antonio Aarao
Published: September 2007

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, please click on HTML or PDF.
New Approach to 3‐Aminothiophene‐2‐carboxylic Acid Derivatives: Access to 5‐Aryl‐4‐(ethylsulfanyl) Compounds.
Authors: Lassagne Frederic , Pochat Francis , Sinbandhit Sourisak
Published: September 2007

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, please click on HTML or PDF.
Microwave‐Enhanced Rhodium‐Catalyzed Conjugate‐Addition of Aryl Boronic Acids to Unprotected Maleimides.
Authors: Iyer Pravin S. , O'Malley Meaghan M. , Lucas Matthew C.
Published: September 2007

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, please click on HTML or PDF.
Synthesis of Indole Analogues of the anti‐Helicobacter pylori Compounds CJ‐13,015, CJ‐13,102, CJ‐13,104 and CJ‐13,108.
Authors: Wilson Zoe E. , Heapy Amanda M. , Brimble Margaret A.
Published: September 2007

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, please click on HTML or PDF.
One‐Pot Synthesis of Benzimidazoles from o‐Nitroanilines under Microwaves via a Reductive Cyclization.
Authors: Surpur Mandar P. , Singh Pankajkumar R. , Patil Sachin B. , Samant Shriniwas D.
Published: September 2007

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, please click on HTML or PDF.
A Fast and Efficient Bromination of Isoxazoles and Pyrazoles by Microwave Irradiation.
Authors: Li Guo , Kakarla Ramesh , Gerritz Samuel W.
Published: September 2007

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, please click on HTML or PDF.
Synthesis of 5‐Alkyl(aryl)sulfanyl‐4‐chloro‐3‐trichloromethyl‐1,2‐thiazoles and 5‐Alkyl(aryl)sulfanyl‐4‐chloro‐1,2‐thiazole‐3‐carboxylic Acids
Authors: Potkin V. I. , Nechai N. I. , Kaberdin R. V.
Published: September 2007

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, please click on HTML or PDF.
Microwave‐Promoted Efficient Synthesis of 3‐(5‐Arylfuran‐2‐yl)‐6‐aryl/aryloxymethylene‐1,2,4‐s‐triazolo [3,4‐b]‐1,3,4‐thiadiazoles.
Authors: Wang Xi‐Cun , Liu Juan
Published: September 2007

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, please click on HTML or PDF.
Synthesis of 1,3,4‐Trisubstituted Isoquinolines by Iodine‐Mediated Electrophilic Cyclization of 2‐Alkynyl Benzyl Azides.
Authors: Fischer Dirk , Tomeba Hisamitsu , Pahadi Nirmal K. , Patil Nitin T. , Yamamoto Yoshinori
Published: September 2007

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, please click on HTML or PDF.
Unusual Synthesis of Dihydropyrido[2,1‐a]isoindolone Derivatives by Radical Cyclization of Enamides of Baylis—Hillman Adducts.
Authors: Gowrisankar Saravanan , Kim Seong Jin , Lee Ji‐Eun , Kim Jae Nyoung
Published: September 2007

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, please click on HTML or PDF.
Chemistry of Diazocarbonyl Compounds. Part 30. Development of a Synthetic Approach to Pyridazine Structure via Wittig Reaction of Fluoroalkyl‐Containing Diazo Keto Esters.
Authors: Galiullina S. V. , Zakharova V. M. , Kantin G. P. , Nikolaev V. A.
Published: September 2007

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, please click on HTML or PDF.
3,4‐Dibromotetrahydro‐γ6‐thiophene 1,1‐Dioxide in S,N‐Tandem Heterocyclizations. Synthesis of Tetrahydrothienothiazolopyrimidines.
Authors: Shklyarenko A. A. , Yakovlev V. V.
Published: September 2007

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, please click on HTML or PDF.
Combined Claisen Rearrangement and Olefin Metathesis as a Route to Diverse Naphthalene Derivatives.
Authors: Chattopadhyay Shital K. , Ghosh Debalina , Neogi Kaushik
Published: September 2007

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, please click on HTML or PDF.
Semisynthesis and Antifeedant Activity of New Acylated Derivatives of Tutin, a Sesquiterpene Lactone from Coriaria sinica.
Authors: Li Meng‐Lou , Cui Jun , Qin Rui‐Hao , Gao Jin‐Ming , Zhang Yan‐Bing , Guo Xin‐Rong , Zhang Wei
Published: September 2007

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, please click on HTML or PDF.
Convenient Preparation of Chiral Phase‐Transfer Catalysts with Conformationally Fixed Biphenyl Core for Catalytic Asymmetric Synthesis of α‐Alkyl‐ and α,α‐Dialkyl‐α‐amino Acids: Application to the Short Asymmetric Synthesis of BIRT‐377.
Authors: Wang Yong‐Gang , Ueda Mitsuhiro , Wang Xisheng , Han Zhenfu , Maruoka Keiji
Published: September 2007

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, please click on HTML or PDF.
Total Synthesis of (‐)‐Stemoamide (I).
Authors: Torssell Staffan , Wanngren Emil , Somfai Peter
Published: September 2007

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, please click on HTML or PDF.
Acid‐Catalyzed Aza‐Diels—Alder Reactions for the Total Synthesis of (.+‐.)‐Lapatin B (I).
Authors: Leca Dominique , Gaggini Francesca , Cassayre Jerome , Loiseleur Olivier , Pieniazek Susan N. , Luft Jennifer A. R. , Houk K. N.
Published: September 2007

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, please click on HTML or PDF.
Synthesis of Anabaseine and Anabasine Derivatives: Structural Modifications of Possible Nicotinic Agonists.
Authors: Sobarzo‐Sanchez Eduardo , Castedo Luis , De la Fuente Julio R.
Published: September 2007

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, please click on HTML or PDF.
Total Synthesis of Pulchellalactam via an RCM Strategy.
Authors: Chavan Subhas P. , Pathak Ashok B. , Dhawane Abasaheb N. , Kalkote U. R.
Published: September 2007

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, please click on HTML or PDF.
Mupirocin H (I), a Novel Metabolite Resulting from Mutation of the HMG‐CoA Synthase Analogue, mupH in Pseudomonas fluorescens.
Authors: Wu Ji'en , Cooper Sian M. , Cox Russell J. , Crosby John , Crump Matthew P. , Hothersall Joanne , Simpson Thomas J. , Thomas Christopher M. , Willis Christine L.
Published: September 2007

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, please click on HTML or PDF.
Synthesis and Stereochemical Assignment of FR252921, a Promising Immunosuppressant.
Authors: Falck J. Russell , He Anyu , Fukui Hiroki , Tsutsui Hideyuki , Radha Akella
Published: September 2007

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, please click on HTML or PDF.
Unbiasing Scoring Functions: A New Normalization and Rescoring Strategy.
Authors: Carta Giorgio , Knox Andrew J. S. , Lloyd David G.
Published: September 2007

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, please click on HTML or PDF.
Use of Ionic Liquids in the Synthesis of Nanocrystals and Nanorods of Semiconducting Metal Chalcogenides.
Authors: Biswas Kanishka , Rao C. N. R.
Published: September 2007

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, please click on HTML or PDF.
Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications
Authors: Chen Xiaobo , Mao Samuel S.
Published: September 2007

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, please click on HTML or PDF.
Review of the Synthetic Chemistry Involved in the Production of Core/Shell Semiconductor Nanocrystals
Authors: van Embden Joel , Jasieniak Jacek , Gomez Daniel E. , Mulvaney Paul , Giersig Michael
Published: September 2007

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, please click on HTML or PDF.
Gas Phase Synthesis of Nanoparticles and Their Growth Control
Authors: Choi Mansoo
Published: September 2007

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, please click on HTML or PDF.
Complexes with Fe2III(μ‐O)(μ‐OH) Core Surrounded by Hydrogen‐Bonding Interaction
Authors: Honda Yasutaka , Arii Hidekazu , Okumura Takeshi , Wada Akira , Funahashi Yasuhiro , Ozawa Tomohiro , Jitsukawa Koichiro , Masuda Hideki
Published: September 2007

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, please click on HTML or PDF.
Supramolecular Aspects of Tin and Lead Chemistry
Authors: Haiduc Ionel
Published: September 2007

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, please click on HTML or PDF.
Ionic Liquids
Authors: Stark Annegret , Seddon Kenneth R.
Published: September 2007

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, please click on HTML or PDF.
Total Synthesis of Complex Cyclotryptamine Alkaloids: Stereocontrolled Construction of Quaternary Carbon Stereocenters
Authors: Steven Alan , Overman Larry E.
Published: September 2007

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, please click on HTML or PDF.
Medicinal Chemistry of Ferrocene
Authors: Fouda Mohammad F. R. , Abd‐Elzaher Mokhles M. , Abdelsamaia Rafeek A. , Labib Ammar A.
Published: September 2007

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, please click on HTML or PDF.
Catalytic Asymmetric Synthesis of Biologically Active Molecules
Authors: Kanai Motomu , Shibasaki Masakatsu
Published: September 2007

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, please click on HTML or PDF.
Prostate‐specific antigen velocity and the detection of gleason score 7 to 10 prostate cancer
Authors: Punglia Rinaa S. , Cullen Jennifer , McLeod David G. , Chen Yongmei , D'Amico Anthony V.
Published: September 2007

BACKGROUND.

An increasing prostate‐specific antigen (PSA) velocity is associated with a shorter survival after local therapy for prostate cancer. In this study, the authors evaluated whether PSA velocity was associated with prostate cancer detection and grade at diagnosis after adjusting for established predictors.

METHODS.

Between January 1989 and December 2003, 914 men who had PSA levels ≥4 ng/mL were identified by using the Center for Prostate Disease Research (CPDR) multicenter national database, including 541 men who were diagnosed with prostate cancer. Multivariable logistic regression analyses were performed that included continuous variables (PSA velocity and level, number of prior negative biopsies, and age) along with categorical variables (ethnicity and family history) were used to identify the factors associated with prostate cancer detection and grade.

RESULTS.

An increasing PSA velocity was associated with Gleason scores from 7 to 10 versus Gleason scores form 2 to 6 or no cancer (adjusted odds ratio [OR], 1.04 ng/mL per year; 95% confidence interval [95% CI], 1.003–1.085 ng/mL per year; P = .035). This finding was not evident in patients who had prostate cancers with Gleason scores between 2 and 6 or for any prostate cancer. PSA level was associated with the detection of any prostate cancer (OR, 1.06 ng/mL; 95% CI, 1.03–1.10 ng/mL; P = .004) and Gleason score ≤6 prostate cancer (OR, 1.06 ng/mL; 95% CI, 1.02–1.10 ng/mL; P = .0027); however, in the presence of PSA velocity, PSA no longer remained independently predictive for high‐grade prostate cancer (OR, 1.01 ng/mL; 95% CI, 0.98–1.04 ng/mL; P = .45) after adjusting for established predictors.

CONCLUSIONS.

PSA velocity enhanced the detection of high‐grade cancer in men who had PSA levels >4 ng/mL. These findings, in conjunction with life expectancy, may be used when deciding which men should not be recommended for prostate biopsy despite a PSA level >4 ng/mL. Cancer 2007. © 2007 American Cancer Society.
Accuracy of pleural biopsy using thoracoscopy for the diagnosis of histologic subtype in patients with malignant pleural mesothelioma
Authors: Greillier Laurent , Cavailles Arnaud , Fraticelli Anne , Scherpereel Arnaud , Barlesi Fabrice , Tassi Gianfranco , Thomas Pascal , Astoul Philippe
Published: September 2007

BACKGROUND.

Promising results with trimodality therapy combining surgery, chemotherapy, and radiotherapy have been obtained in the management of patients with malignant pleural mesothelioma (MPM). However, the histologic subtype has to be taken into account because of its influence on prognosis. The aim of the current study was to analyze retrospectively the accuracy, sensitivity, and specificity of preoperative thoracoscopy for diagnosis of the histologic subtype of MPM.

METHODS.

The histologic reports from all consecutive patients undergoing ‘intent‐to‐treat’ surgery from 3 institutions as well as the initial pathologic diagnosis obtained using thoracoscopy were reviewed and compared after institutional review board approval. All cases of MPM were confirmed by a panel of pathologists.

RESULTS.

Ninety‐five patients were included in the current study. Of these 95 patients, 75 underwent extrapleural pneumonectomy, 9 patients underwent pleurectomy/decortication, and 11 patients underwent pleurectomy. Of the 95 patients with a final diagnosis of MPM, 80 (84.2%) were classified as having epithelial and 15 (15.8%) as having biphasic subtype. Among the 87 patients classified as having MPM of epithelial subtype after the initial thoracoscopy, 75 cases (86.2%) were confirmed to be a true histologic diagnosis and 12 cases (13.8%) were found to be of biphasic subtype at final diagnosis. One patient with a biphasic subtype at initial thoracoscopy was found to have MPM of epithelial subtype after surgery. The sensitivity and specificity values of an epithelial subtype diagnosis after thoracoscopy were 94% and 20%, respectively, with a positive predictive value of 86% and a negative predictive value of 37%. Conversely, the sensitivity and specificity values of a biphasic subtype diagnosis after thoracoscopy were 20% and 98%, respectively, with a positive predictive value of 75% and a negative predictive value of 87%.

CONCLUSIONS.

Pleural biopsy performed using thoracoscopy is considered to be the cornerstone of the diagnosis and pleural staging of MPM. However, this procedure appears to be less efficient in diagnosing the histologic subtype as either epithelial or biphasic. Cancer 2007. © 2007 American Cancer Society.
Stochastic Detection of Motor Protein–RNA Complexes by Single‐Channel Current Recording
Authors: Astier Yann , Kainov Denis E. , Bayley Hagan , Tuma Roman , Howorka Stefan
Published: September 2007

A label‐ and immobilization‐free approach to detecting the reversible formation of complexes between nucleic acids and proteins at the single‐molecule level is described. The voltage‐driven translocation of individual oligoribonucleotides through a nanoscale protein pore is observed by single‐channel current recordings. The oligoribonucleotide 5′‐C25A25‐3′ gives rise to current blockades with an average duration of approximately 0.5 ms. In the presence of the RNA‐binding ATPase P4, a viral packaging motor from bacteriophage ϕ8, longer events of tens to hundreds of milliseconds are observed. Upon addition of ATP the long events disappear, indicating the dissociation of the P4⋅RNA complex. The frequency of events also depends on the concentration of P4 and the length of the oligoribonucleotide, thereby confirming the specificity of the P4⋅RNA events. This study shows that single‐channel current recordings can be used to monitor RNA–protein complex formation, thus opening up a new means to examine the motor activity of RNA‐ or DNA‐processing enzymes.
States of Water Located in the Continuous Organic Phase of 1‐Butyl‐3‐methylimidazolium Tetrafluoroborate/Triton X‐100/Triethylamine Reverse Microemulsions
Authors: Li Na , Cao Quan , Gao Yanan , Zhang Jin , Zheng Liqiang , Bai Xiangtao , Dong Bin , Li Zhen , Zhao Mingwei , Yu Li
Published: September 2007

We demonstrate a novel ionic liquid (IL) microemulsion, consisting of 1‐butyl‐3‐methylimidazolium tetrafluoroborate (bmimBF4) and nonionic surfactant Triton X‐100 prepared in triethylamine which is used either as an organic solvent or a Lewis base. The effects of small amounts of added water on the microstructure of the IL microemulsion are investigated by various techniques. UV/Vis spectroscopic analysis and FTIR spectra indicate that these water molecules are not solubilized into the IL pools of the microemulsions. 1H NMR spectra further show that the added water binds with triethylamine to form a surrounding OH− base environment. Some of OH− ions enter the palisade layers of the IL microemulsions and a continuous base interface is created. The unique solubilization behavior of water reveals that it is possible to use the triethylamine microemulsions as a template to prepare metal hydroxides as well as metal oxides in the microemulsions, which is not possible when using traditional microemulsions.
A unified quality of recovery (QoR) measure
Authors: Chołda P. , Jajszczyk A. , Wajda K.
Published: September 2007

In this paper, carefully selected factors, playing an important role in the choice of recovery procedures applied in communication networks, are combined to form a unified quality of recovery measure. An example that shows how to use the proposed measure and how to draw conclusions from such numerical results is given. Copyright © 2007 John Wiley & Sons, Ltd.
(Benzimidazolylmethyl)cyclen: A Potential Sensitive Fluorescent PET Chemosensor for Zinc
Authors: El Majzoub Abir , Cadiou Cyril , Déchamps‐Olivier Isabelle , Chuburu Françoise , Aplincourt Michel
Published: September 2007

A new fluorescent probe for Zn2+, methylbenzimidazole‐pendant cyclen [LH: 1‐(benzimidazol‐2‐ylmethyl)‐1,4,7,10‐tetraazacyclododecane] was designed and synthesized. The protonation constants of (benzimidazolylmethyl)cyclen and the stability constants of the corresponding zinc complex were determined by potentiometric titrations. The single‐crystal X‐ray diffraction analysis showed that LH and Zn2+ form a 1:1 complex [ZnLH]2+. The results of potentiometric, 1H NMR and UV titrations indicated that above pH 8, [ZnLH]2+ mainly deprotonates into [ZnL]+. On addition of successive amounts of Zn2+ at pH 10.4 (2 × 10–2 mol L–1 CAPS, 25 °C), the fluorescence emission of cyclen(methylbenzimidazole) increases linearly by a factor of 3.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Nickel(II), Palladium(II) and Rhodium(I) Complexes of New NHC‐Thioether Ligands: Efficient Ketone Hydrosilylation Catalysis by a Cationic Rh Complex
Authors: Wolf Joffrey , Labande Agnès , Daran Jean‐Claude , Poli Rinaldo
Published: September 2007

Five new, bifunctional imidazolium–thioether ligands of the general formula RS(CH2)n(imidazolium)+ArBr– (n = 2 or 3, R = Et or tBu, Ar = 2,4,6‐trimethylphenyl or 2,6‐diisopropylphenyl) have been synthesised in good overall yields by a general method and used as N‐heterocyclic carbene precursors for complexation studies on various transition metals (NiII, PdII and RhI). Sulfur does not coordinate the nickel centre, whereas the two functional groups bind the palladium centre to form a dinuclear compound. Cationic rhodium(I) complexes have also been prepared and preliminary catalytic tests show that they have good activity for the hydrosilylation of ketones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Preparation and Characterization of a Ligand‐Stabilized Trimethylphosphane Dication
Authors: Weigand Jan J. , Burford Neil , Decken Andreas , Schulz Axel
Published: September 2007

The ditriflate salt of the DMAP‐stabilized trimethylphosphane dication is formed from the reaction of chlorotrimethylphosphonium triflate with DMAP (4‐dimethylaminopyridine) in the presence of trimethylsilyltriflate and also from the reaction of DMAP‐dimethylphosphenium triflate with methyltriflate. The coordinative nature of the DMAP–phosphorus bond is demonstrated by a ligand exchange of DMAP for PMe3 to give the hexamethyldiphosphonium dication. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Highly Enantioselective Biohydrolysis of sec‐Alkyl Sulfate Esters with Inversion of Configuration Catalysed by Pseudomonas spp.
Authors: Gadler Petra , Faber Kurt
Published: September 2007

In search of highly enantioselective microbial sec‐alkyl sulfatase activity, a broad screening among bacteria, fungi andArchaea revealed several Ralstonia and Pseudomonas spp. as valuable sources, whereas fungi were completely inactive. In particular, Pseudomonas sp. DSM 6611 was able to hydrolyse the (R) enantiomers of a broad range of rac‐sec‐alkyl sulfate esters with excellent enantioselectivities (E > 200) to furnish the corresponding inverted (S)‐sec‐alcohols in high ee's. The substrate range of this organism was remarkably broad and bulky groups were also nicely tolerated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A cell by cell anisotropic adaptive mesh ALE method
Authors: Morrell J. M. , Sweby P. K. , Barlow A.
Published: September 2007

A cell by cell anisotropic adaptive mesh Arbitrary Lagrangian Eulerian (ALE) method for the solution of the Euler equations is described. An efficient approach to equipotential mesh relaxation on anisotropically refined meshes is developed. Results for two test problems are presented. © British Crown Copyright 2007/MOD. Reproduced with permission. Published by John Wiley & Sons, Ltd.
Adaptive‐quadrature fluctuation‐splitting schemes for the Euler equations
Authors: Nishikawa Hiroaki
Published: September 2007

In this paper, we present fluctuation‐splitting schemes that can capture an isolated shock over a suitably oriented single triangular element and also recognize a rarefaction. A particular focus is on the evaluation of the fluctuation (or the cell residual): a one‐parameter‐family quadrature rule is employed to evaluate the fluctuation, which endows the fluctuation with a wave recognition capability. The parameter value is chosen based on the nature of the nonlinear wave passing through the element, and then the resulting fluctuation is distributed to the nodes. This strategy, combined with various distribution schemes, defines a family of adaptive‐quadrature fluctuation‐splitting schemes. The results demonstrate the superior ability of the new schemes in handling nonlinear waves compared with standard fluctuation‐splitting schemes that cannot capture shocks over a single element and also admits nonphysical shocks unless some kind of entropy fix is incorporated. Copyright © 2007 John Wiley & Sons, Ltd.
Simple treatment of non‐aligned boundaries in a Cartesian grid shallow flow model
Authors: Liang Qiuhua , Borthwick Alistair G. L.
Published: September 2007

A simple method is proposed for treating curved or irregular boundaries in Cartesian grid shallow flow models. It directly evaluates fictional values in ‘ghost’ cells adjacent to boundary cells and requires no interpolation or generation of cut cells. The boundary treatment is implemented in a dynamically adaptive quadtree grid‐based solver of the hyperbolic shallow water equations and validated against several test cases with analytical or alternative numerical solutions. The method is easy to code, accurate, and demonstrably effective in dealing with irregular computational domains in shallow flow simulations. Results are presented for still water in a basin of complicated geometry, steady hydraulic jump in an open channel with a converging sidewall, wind‐induced circulation in a circular shallow lake, and shock wave diffraction in a channel containing a contraction and expansion. Copyright © 2007 John Wiley & Sons, Ltd.
Accuracy of SPH viscous flow models
Authors: Graham David I. , Hughes Jason P.
Published: September 2007

In this paper, we quantify how the accuracy of 1D and 2D smoothed particle hydrodynamics simulations of viscous diffusion depend upon (i) the mean inter‐particle distance Δx, (ii) the smoothing length h and (iii) the randomness of the particle positions. In both the 1D and 2D cases, the method converges only in the case where randomness is absent and for a few values of h/Δx including both integer (for 1D) and non‐integer values (both 1D and 2D). For any other (fixed) value of h/Δx, the method does not converge. In most cases, increasing randomness decreases the accuracy of the results, as does the ability of particles to move. Simulations using larger values of h/Δx appear to be less influenced by particle randomness and ability to move. Copyright © 2007 John Wiley & Sons, Ltd.
Rapid increase of glial glutamate uptake via blockade of the protein kinase A pathway
Authors: Adolph Oliver , Köster Sarah , Räth Monika , Georgieff Michael , Weigt Henry U. , Engele Jürgen , Senftleben Uwe , Föhr Karl J.
Published: September 2007

Glutamate is the main excitatory neurotransmitter in the vertebrate central nervous system. Removal of this transmitter from the synaptic cleft by glial and neuronal transporter systems plays an important role in terminating glutamatergicneurotransmission. The effects of different activators and blockers of PKA and PKC on glutamate uptake were studied in primary glial cells cultivated from the rat cortex using the patch‐clamp recording technique and immunocytochemical methods. GF 109203X enhances glutamate‐induced membrane currents in a concentration‐ and time‐dependent manner. After pre‐application for 40 s the maximal transport capacity was increased by 30–80%. The estimatedKm‐value of the transport system did not change after drug application and the enhanced glutamate uptake was reversible within a few minutes upon washout. Activators and blockers of the PKC pathway did not affect glutamate uptake, whereas H89, a selective blocker of PKA, mimicked the effects of GF 109203X, indicating involvement of the protein kinase A pathway. The GF 109203X‐induced increase in transport capacity is likely to be mediated by GLAST since the GLT‐1 selective blocker dihydrokainate was unable to block basal or stimulated glutamate uptake. Furthermore, the increase in transport activity may well be based on an increase in cell surface expression of the transporter protein since preincubation with cytochalasin‐B, a protein that blocks actin polymerization, almost completely abolished the effect of GF 109203X and H89. These results indicate that GF 109203X and H89 enhance glial glutamate uptake via blockade of the PKA. The described effect may affect glutamatergic neurotransmission by reducing the glutamate concentration in the synaptic cleft. © 2007 Wiley‐Liss, Inc.
A delicate dance
Authors: Tomlinson‐Keasey Carol
Published: September 2007

The major challenges in building the tenth University of California campus did not come from the academic arena. They came from the political arena.
A fragile birth
Authors: Desrochers Lindsay A.
Published: September 2007

The direction of California society and politics has made it more and more difficult to deliver on the dream of ready access to a University of California education for the state's qualified high school graduates