bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile Preparation of Mono‐, Di‐ and Mixed‐Carboxylato Platinum(IV) Complexes for Versatile Anticancer Prodrug Design
Authors: Zhang Jenny Z. , Bonnitcha Paul , Wexselblatt Ezequiel , Klein Alice V. , Najajreh Yousef , Gibson Dan , Hambley Trevor W. 
Published: December 2012

AbstractFacile strategies were developed for the versatile functionalization of platinum(IV) axial sites, allowing for easy accessibility to unsymmetric mono‐ and mixed‐carboxylato, as well as symmetric di‐substituted platinum(IV) complexes. The first method involves the direct oxidation and carboxylation of the platinum(II) center using an appropriate peroxide and the carboxylate of choice to firstly yield a monocarboxylato monohydroxido platinum(IV) complex. This platinum(IV) intermediate can undergo further carboxylation to give rise to a mixed‐carboxylato platinum(IV) complex. The second method involves the activation of the carboxylate of choice by a common carbodiimide coupling reagent, and its reaction with a dihydroxido platinum(IV) precursor to give the monocarboxylato platinum(IV) complex. Uronium salts can be employed to promote efficient dicarboxylation of the dihydroxido platinum(IV) precursor. Lastly, an axial azide pendant group was demonstrated to be suitable for orthogonal “click” conjugation reactions.
Highly Efficient Enantioselective Construction of Bispirooxindoles Containing Three Stereocenters through an Organocatalytic Cascade Michael–Cyclization Reaction
Authors: Wu Hao , Zhang Li‐Li , Tian Zhi‐Qing , Huang Yao‐Dong , Wang Yong‐Mei 
Published: December 2012

AbstractBispirooxindole derivatives containing three stereocenters, including two spiro quaternary centers, were synthesized in a high‐yielding, atypically rapid, and stereocontrolled cascade Michael–cyclization reaction between methyleneindolinones and isothiocyanato oxindoles catalyzed by a bi‐ or multifunctional organocatalyst. Mild conditions were used to construct bispirooxindoles with excellent enantio‐ and diastereomeric purities within less than 1 min. Catalyst reconfiguration offered access to the opposite enantiomer. This exceptionally highly efficient procedure will allow diversity‐oriented syntheses of this intriguing class of compounds with potential biological activities.
Interplay between the Diradical Character and Third‐Order Nonlinear Optical Properties in Fullerene Systems
Authors: Muhammad Shabbir , Fukuda Kotaro , Minami Takuya , Kishi Ryohei , Shigeta Yasuteru , Nakano Masayoshi 
Published: December 2012

AbstractTo reveal new structure–property relationships in the nonlinear optical (NLO) properties of fullerenes that are associated with their open‐shell character, we investigated the interplay between the diradical character (yi) and second hyperpolarizability (longitudinal component, γzzzz) in several fullerenes, including C20, C26, C30, C36, C40, C42, C48, C60, and C70, by using the broken‐symmetry density functional theory (DFT; LC‐UBLYP (μ=0.33)/6‐31G*//UB3LYP/6‐31G*). We found that the large differences between the geometry and topology of fullerenes have a significant effect on the diradical character of each fullerene. On the basis of their different diradical character, these fullerenes were categorized into three groups, that is, closed‐shell (yi=0), intermediate open‐shell (0<yi<1), and almost pure open‐shell compounds (yi≅1), which originated from their diverse topological features, as explained by odd‐electron‐density and spin‐density diagrams. For example, we found that closed‐shell fullerenes include C20, C60, and C70, whereas fullerenes C26 and C36 and C30, C40, C42, and C48 are pure and intermediate open‐shell compounds, respectively. Interestingly, the γzzzz enhancement ratios between C30/C36 and C40/C60 are 4.42 and 11.75, respectively, regardless of the smaller π‐conjugation size in C30 and C40 than in C36 and C60. Larger γzzzz values were obtained for other fullerenes that had intermediate diradical character, in accordance with our previous valence configuration interaction (VCI) results for the two‐site diradical model. The γzzzz density analysis shows that the large positive contributions originate from the large γzzzz density distributions on the right‐ and left‐extended edges of the fullerenes, between which significant spin polarizations (related to their intermediate diradical character) appear within the spin‐unrestricted DFT level of theory.
ChemInform Abstract: Inorganic Double‐Helix Structures of Unusually Simple Lithium—Phosphorous Species.
Authors: Ivanov Alexander S. , Morris Andrew J. , Bozhenko Konstantin V. , Pickard Chris J. , Boldyrev Alexander I. 
Published: December 2012

AbstractThe existence of double‐helix structures in the series of LixPx (x = 5—9) clusters and in an infinite LiP chain are theoretical predicted by quantum chemical calculations using B3LYP and CCSD(T) methods.
ChemInform Abstract: BaGa2GeX6 (X: S, Se): New mid‐IR Nonlinear Optical Crystals with Large Band Gaps.
Authors: Lin Xinsong , Guo Yifeng , Ye Ning 
Published: December 2012

AbstractThe title compounds are prepared by solid state reaction of BaS, Ga, Ge, and S or Se (700 °C for 70 h and 1000 °C for 3 d).
ChemInform Abstract: Metal‐ and Chemical‐Oxidant‐Free C—H/C—H Cross‐Coupling of Aromatic Compounds: The Use of Radical‐Cation Pools.
Authors: Morofuji Tatsuya , Shimizu Akihiro , Yoshida Jun‐ichi 
Published: December 2012

AbstractAromatic compounds react with aryl radical cations, which are generated and accumulated by low‐temperature electrolysis from the corresponding arenes.
ChemInform Abstract: Regioselectivity Switch: Gold(I)‐Catalyzed Oxidative Rearrangement of Propargyl Alcohols to 1,3‐Diketones.
Authors: Hashmi A. Stephen K. , Wang Tao , Shi Shuai , Rudolph Matthias 
Published: December 2012

AbstractThe Au‐catalyzed treatment of propargyl alcohols with pyridine‐N‐oxides allows a mild, efficient, and selective access to various synthetically important 1,3‐diketones.
ChemInform Abstract: Efficient and Eco‐Friendly Synthesis of Iodinated Aromatic Building Blocks Promoted by Iodine and Hydrogen Peroxide in Water: A Mechanistic Investigation by Mass Spectrometry.
Authors: Gallo Rafael D. C. , Ferreira Irlon M. , Casagrande Gleison A. , Pizzuti Lucas , Oliveira‐Silva Diogo , Raminelli Cristiano 
Published: December 2012

AbstractThe reaction of aromatic compounds with molecular iodine in the presence of aqueous hydrogen peroxide gives mono‐, di‐ and triiodinated arenes and hetarenes under the same conditions.
ChemInform Abstract: Gold(I)‐Catalyzed Addition of Thiols and Thioacids to 3,3‐Disubstituted Cyclopropenes.
Authors: Mudd Richard J. , Young Paul C. , Jordan‐Hore James A. , Rosair Georgina M. , Lee Ai‐Lan 
Published: December 2012

AbstractTreatment of cyclopropenes of type (I) with thiols in the presence of AUC results in regio‐ and chemoselective formation of vinylic thioethers like (III).
ChemInform Abstract: Highly Enantioselective Conjugate Addition of Malononitrile to 2‐Enoylpyridines with Bifunctional Organocatalyst.
Authors: Molleti Nagaraju , Rana Nirmal K. , Singh Vinod K. 
Published: December 2012

AbstractIt is found that the chiral urea catalysts (QUI) and (URE) efficiently promote the asymmetric conjugate addition of malononitrile to a number of 2‐enoylpyridines and related compounds like (VII).
ChemInform Abstract: Potash Alum [KAl(SO4)2·12H2O] Catalyzed Esterification of Formylphenoxyaliphatic Acids.
Authors: Kumar Ganesan Shunmugadhas Suresh , Kumaresan Sudalaiandi 
Published: December 2012

AbstractA new protocol for the esterification of formylphenoxyaliphatic acids (I) using potash alum as heterogeneous catalyst developed and applied to the synthesis of ibuprofen prodrugs (VI).
ChemInform Abstract: Efficient Room‐Temperature O‐Silylation of Alcohols Using a SBA‐15‐Supported Cobalt(II) Nanocatalyst.
Authors: Rajabi Fatemeh , Luque Rafael , Serrano‐Ruiz Juan Carlos 
Published: December 2012

AbstractThe procedure is successfully applied to various substrates (alcohols, phenols, diols and triols) without affecting other functional groups and the protection is complete within a short time.
ChemInform Abstract: Novel Broensted Acidic Deep Eutectic Solvent as Reaction Media for Esterification of Carboxylic Acid with Alcohols.
Authors: De Santi Valerio , Cardellini Fabio , Brinchi Lucia , Germani Raimondo 
Published: December 2012

AbstractA quaternary ammonium methanesulfonate is used as both reusable catalyst and solvent.
ChemInform Abstract: Copper(I)‐Catalyzed Amination of Aryl Halides in Liquid Ammonia.
Authors: Ji Pengju , Atherton John H. , Page Michael I. 
Published: December 2012

AbstractCuI in combination with ascorbic acid promotes the coupling of aromatic iodides and bromides with liquid NH3 and allows selective formation of a number of primary amines in good to high yields.
ChemInform Abstract: Chemo‐ and Regioselective Direct Hydroxylation of Arenes with Hydrogen Peroxide Catalyzed by a Divanadium‐Substituted Phosphotungstate.
Authors: Kamata Keigo , Yamaura Taiyo , Mizuno Noritaka 
Published: December 2012

AbstractThe treatment of the divanadium phosphotungstate with HClO4 generates in situ the [γ‐PW10O38V2(μ‐OH)2] 3‐ species which shows high catalytic activity in the hydroxylation of various aromatic compounds with aqueous H2O2.
ChemInform Abstract: Synthesis of Diarylmethanes via a Friedel—Crafts Benzylation Using Arenes and Benzyl Alcohols in the Presence of Triphenylphosphine Ditriflate.
Authors: Khodaei Mohammad Mehdi , Nazari Ehsan 
Published: December 2012

AbstractA mixture of triphenylphosphine oxide and triflic anhydride generates the title reagent, which is demonstrated to be an efficient promotor for the procedure.
ChemInform Abstract: Rhodium‐Catalyzed Dimerization of Diaryl Acetylenes in the Presence of Grignard Reagents: Synthesis of 1,2,3‐Triphenyl Naphthalene Derivatives.
Authors: Qian Pengcheng , Chen Fan , Pan Changduo 
Published: December 2012

AbstractThe mechanism of the presented hydroarylation reaction remains unclear at present.
ChemInform Abstract: Aziridine‐2‐carboxaldehyde Dimers Undergo Homo‐Ugi 4‐Component‐5‐center Reactions.
Authors: Rotstein Benjamin H. , Yudin Andrei K. 
Published: December 2012

AbstractEnantiopure aziridine‐substituted bicyclic oxazolidines, so called α‐aziridine aldehydes, are applied as substrates in Ugi and Passerini reactions to give highly functionalized scaffolds as diastereomeric mixtures.
ChemInform Abstract: Enantioselective Organocatalyzed Sulfenylation of 3‐Substituted Oxindoles.
Authors: Li Xin , Liu Cong , Xue Xiao‐Song , Cheng Jin‐Pei 
Published: December 2012

AbstractQunidine‐catalyzed treatment of Boc‐protected 3‐substituted oxindoles with (arylthio)phthalimides is found to allow a highly enantioselective access to 3‐sulfurated derivatives of type (III) and (V) which are of biological and chemical interest.
ChemInform Abstract: Palladium‐Catalyzed Tandem Allenyl and Aryl C—N Bond Formation: Efficient Access to N‐Functionalized Multisubstituted Indoles.
Authors: Liu Bingxin , Hong Xiaohu , Yan Dong , Xu Shuguang , Huang Xiaomei , Xu Bin 
Published: December 2012

AbstractRelated compounds such as (XII) are also available.
ChemInform Abstract: Palladium‐Catalyzed Direct Arylation of 5‐Chloropyrazoles: A Selective Access to 4‐Aryl Pyrazoles.
Authors: Yan Tao , Chen Lu , Bruneau Christian , Dixneuf Pierre H. , Doucet Henri 
Published: December 2012

AbstractA number of 4‐arylated pyrazoles can be prepared efficiently.
ChemInform Abstract: Synthesis of Bicyclic Imidazoles via [2 + 3] Cycloaddition Between Nitriles and Regioselectively Generated α‐Imino Gold Carbene Intermediates.
Authors: Xiao Yuanjing , Zhang Liming 
Published: December 2012

AbstractBy use of AuCl3 as catalyst, the title reaction of terminal azidoalkynes with nitriles occurs predominantly, and the competing intramolecular Huisgen reaction leading to fused triazole derivatives is minimized (mostly < 20% NMR yield).
ChemInform Abstract: Copper‐Catalyzed Synthesis of 2‐Aminobenzimidazoles from Carbonimidoyl Dichlorides and Amines.
Authors: Yu Hui , Liu Qiong , Li Yuzhe , Ni Chongzhi 
Published: December 2012

AbstractThe reaction of o‐haloaryl substituted carbonimidoyl dichlorides with various primary amines produces guanidine intermediates which undergo ring closure in the presence of CuI.
ChemInform Abstract: Synthesis and Antioxidant Activity of a New Class of Bis and Tris Heterocycles.
Authors: Padmavathi Venkatapuram , Venkatesh Bhumireddy C. , Muralikrishna Akkarapalli , Padmaja Adivireddy 
Published: December 2012

AbstractThe bisbenzoxazolylisoxazole (Va) exhibits good antioxidant activity compared to the standard ascorbic acid.
ChemInform Abstract: Stereoselective Isoxazolidine Synthesis via Copper‐Catalyzed Alkene Aminooxygenation.
Authors: Karyakarte Shuklendu D. , Smith Thomas P. , Chemler Sherry R. 
Published: December 2012

AbstractCu‐catalyzed treatment of butenylated hydroxylamines with the radical (II) allows a new and stereoselective access to isoxazolidines.
ChemInform Abstract: One‐Pot Synthesis of 2,4‐Disubstituted Thiazoline from β‐Azido Disulfide and Carboxylic Acid.
Authors: Liu Yi , Liu Jun , Qi Xiangbing , Du Yuguo 
Published: December 2012

AbstractIt provides a facile and efficient method to prepare disubstituted thiazolines which are of biological interest.
ChemInform Abstract: Synthesis of 4‐Substituted Pyrano[4,3‐b]pyran‐2,5‐diones in an Ionic Liquid.
Authors: Rad‐Moghadam Kurosh , Sharifi‐Kiasaraie Masoumeh , Azimi Seyyedeh Cobra 
Published: December 2012

AbstractA mildly basic ionic liquid is used both as solvent and catalyst for the synthesis of the title compounds.
ChemInform Abstract: Direct Carbo‐Acylation Reactions of 2‐Arylpyridines with α‐Diketones via Pd‐Catalyzed C—H Activation and Selective C(sp2)—C(sp2) Cleavage.
Authors: Zhou Wei , Li Hongji , Wang Lei 
Published: December 2012

AbstractIn the presence of tBuOOH, 2‐arylpyridines (I) as well as benzoquinoline (IX) react with symmetric or asymmetric diketones to give the corresponding acylated products.
ChemInform Abstract: Iron‐Catalyzed Formation of 2‐Aminopyridines from Diynes and Cyanamides.
Authors: Lane Timothy K. , D'Souza Brendan R. , Louie Janis 
Published: December 2012

AbstractSlow addition of diynes to cyanamides in the presence of FeCl2, Zn, and PYR allows an efficient and regioselective access to highly substituted 2‐aminopyridines like (III), (V), and (VII).
ChemInform Abstract: Total Synthesis of Ascididemin via Anionic Cascade Ring Closure.
Authors: Petersen Ida Nymann , Crestey Francois , Kristensen Jesper Langgaard 
Published: December 2012

AbstractAscididemin (III) is readily prepared by microwave‐promoted cyclization of bipyridine (II) followed by benzylic oxidation of intermediate 12‐deoxyascididemin.
Design and Fabrication of a Three Dimensional Spiral Micromixer
Authors: Yang Jun , Qi Li , Chen Yi , Ma Huimin 
Published: December 2012

AbstractIn this work, we present a three dimensional micromixer which consists of two layers of spiral channels overlapped together in the vertical direction. This micromixer is designed by using a smooth channel twisted into double‐layer spiral geometry with simple topological structure. Based on the principle of Dean effects, this kind of structure is beneficial to produce, enhance and sustain the Dean vortices, which can perturb the laminar fluid effectively. In order to improve the mixing performance, the detailed parameters have been optimized by using the computational fluid dynamics software. The results indicate that the erect channel which is connected with the two layers of spiral channels plays a critical role for well mixing. Meanwhile, the effect of mixing has been identified in a fabricated glass‐micromixer. The mixing ef?ciency of 90% has been achieved by optimizing the flow rate and the structure of the erect channel. Thus, this micromixer has manifested high mixing efficiency and presents good practicability in the versatile microfluidic systems.
A Highly Sensitive and Selective Colorimetric Chemosensor for F− Detection Based on Perylene‐3,4:9,10‐tetracarboxylic Bisimide
Authors: Zhang Liang , Wang Limin , Zhang Guanjun , Yu Jianjun , Cai Xiaofei , Teng Mingshuang , Wu Yue 
Published: December 2012

AbstractA novel colorimetric chemosensor PBIOSi has been designed and synthesized. The addition of F− to a THF solution of PBIOSi resulted in an obvious color change (from red to green) in a short time because of the specific cleavage of SiO bond in PBIOSi by F−. It was interesting that PBIOSi showed excellent selectivity for F− detection over other halides. The UV‐Vis absorption and fluorescence were changed linearly with the concentration of F− over the range of 0–10 µmol/L.
Disintegration of Sludge by Sonication and Improvement of Methane Production Rates in Batch Anaerobic Digesters
Authors: Zorba Gozde T. , Sanin F. Dilek 
Published: December 2012

AbstractSludge pretreatment prior to anaerobic digestion has been found to reduce sludge production in wastewater treatment. Sludge disintegration using physical, chemical, biological, or mechanical methods can increase biogas production and reduce sludge quantities. Ultrasonication is one of the most effective means of mechanical disintegration. This study aims to investigate ultrasonication as a means for solubilizing waste activated sludge (WAS) to enhance its digestability. Sonication was applied by the use of two different probes providing different powers and energies into the sludge after which the soluble chemical oxygen demand (sCOD) increases were measured. The samples were then digested anaerobically in 250 mL serum bottles for about 50 days. Along with the biogas measurements, the rate of methane production is calculated to be able to quantify the effect of pretreatment and compare the results between different applications. The results showed that with the increase of sonication power and sonication time, sCOD increased. An introduction of higher sonication energy made the sCOD rise sharply, however, this increase was not indefinite; it became gradually lower with the further increase of energy. The results indicated that specific methane production, specific methane yield, and the first order methane generation rate increased with increasing energy input.
Ecological Risk Assessment of Benzo[a]pyrene in Yellow River Delta
Authors: Jin Qin , Jiang Qunou , Wu Feng , Li Xing , Deng Xiangzheng 
Published: December 2012

AbstractEcological risk assessment is of great significance to promoting the rational management effectively for the oil‐polluted areas. A comprehensive evaluation method of ecological risk, including probabilistic risk assessment and regional ecological risk assessment, is developed through employing the contaminant benzo[a]pyrene as an indicator to assess ecological risk of five oil mining plots, respectively in Yellow River Delta. In this study, firstly we evaluate the ecological risk probability of five oil mining plots using overlapping area of probabilistic curves, and the results show that local ecological risk varies between the maximum 0.4 and the minimum 0.01. Then we overlay boundaries of five administrative divisions in Yellow River Delta and the spatial distribution patterns of ecosystems to generate new risk receptor plaques, and calculate the integrated value of 30 specifically classified plaques for comprehensive evaluation of ecological risk. The results, fluctuating within the range of 0.00005 and 0.25, indicate that local government should be vigilant to ecological risk of benzo[a]pyrene to some extent, although the current situation is not severe in whole.
Biosorption of Heavy Metals in Leachate Derived from Gold Mine Tailings Using Aspergillus fumigatus
Authors: Jalili Seh‐Bardan Bahi , Othman Radziah , Abd Wahid Samsuri , Sadegh‐Zadeh Fardin , Husin Aminudin 
Published: December 2012

AbstractLeachate derived from bioleaching process contains high amount of metals that must be removed before discharging the water. Aspergillus fumigatus was isolated from a gold mine tailings and its ability to remove of As, Fe, Mn, Pb, and Zn from aqueous solutions and leachate of bioleaching processes was assessed. Batch sorption experiments were carried out to characterize the capability of fungal biomass (FB) and iron coated fungal biomass (ICFB) to remove metal ions in single and multi‐solute systems. The maximum sorption capacity of FB for As(III), As(V), Fe, Mn, Pb, and Zn were 11.2, 8.57, 94.33, 53.47, 43.66, and 70.4 mg/g, respectively, at pH 6. For ICFB, these values were 88.5, 81.3, 98.03, 66.2, 50.25, and 74.07 mg/g. Results showed that only ICFB was found to be more effective in removing metal ions from the leachate. The amount of adsorbed metals from the leachate was 2.88, 21.20, 1.91, 0.1, and 0.08 mg/g for As, Fe, Mn, Zn, and Pb, respectively. The FT‐IR analysis showed involvement of the functional groups of the FB in the metal ions sorption. Scanning electron microscopy revealed that surface morphological changed following metal ions adsorption. The study showed that the indigenous fungus A. fumigatus was able to remove As, Fe, Mn, Pb, and Zn from the leachate of gold mine tailings and therefore the potential for removing metal ions from metal‐bearing leachate.
Distribution and intrinsic membrane properties of basal forebrain GABAergic and parvalbumin neurons in the mouse
Authors: McKenna James T. , Yang Chun , Franciosi Serena , Winston Stuart , Abarr Kathleen K. , Rigby Matthew S. , Yanagawa Yuchio , McCarley Robert W. , Brown Ritchie E. 
Published: December 2012

AbstractThe basal forebrain (BF) strongly regulates cortical activation, sleep homeostasis, and attention. Many BF neurons involved in these processes are GABAergic, including a subpopulation of projection neurons containing the calcium‐binding protein, parvalbumin (PV). However, technical difficulties in identification have prevented a precise mapping of the distribution of GABAergic and GABA/PV+ neurons in the mouse or a determination of their intrinsic membrane properties. Here we used mice expressing fluorescent proteins in GABAergic (GAD67‐GFP knock‐in mice) or PV+ neurons (PV‐Tomato mice) to study these neurons. Immunohistochemical staining for GABA in GAD67‐GFP mice confirmed that GFP selectively labeled BF GABAergic neurons. GFP+ neurons and fibers were distributed throughout the BF, with the highest density in the magnocellular preoptic area (MCPO). Immunohistochemistry for PV indicated that the majority of PV+ neurons in the BF were large (>20 μm) or medium‐sized (15–20 μm) GFP+ neurons. Most medium and large‐sized BF GFP+ neurons, including those retrogradely labeled from the neocortex, were fast‐firing and spontaneously active in vitro. They exhibited prominent hyperpolarization‐activated inward currents and subthreshold “spikelets,” suggestive of electrical coupling. PV+ neurons recorded in PV‐Tomato mice had similar properties but had significantly narrower action potentials and a higher maximal firing frequency. Another population of smaller GFP+ neurons had properties similar to striatal projection neurons. The fast firing and electrical coupling of BF GABA/PV+ neurons, together with their projections to cortical interneurons and the thalamic reticular nucleus, suggest a strong and synchronous control of the neocortical fast rhythms typical of wakefulness and REM sleep. J. Comp. Neurol., 521:1225–1250, 2013. © 2012 Wiley Periodicals, Inc.
What Molecular Features Govern the Mechanism of Supramolecular Polymerization?
Authors: Kulkarni Chidambar , Balasubramanian Sundaram , George Subi J. 
Published: December 2012

AbstractAn understanding of the mechanisms of supramolecular polymerization from a molecular point of view is lacking. Several reports in the literature on the mechanism exhibited by different classes of molecules are examined in an attempt to correlate the molecular features to the aggregation pathway followed. It is proposed that long‐range interactions between oligomers could lead to their cooperative growth. The lack thereof leads to isodesmicity.