bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of reaction conditions on intercalation between gelatin and montmorillonite: Thermodynamical impact
Authors: Zheng Junping , Gao Shan , Li Hongyan , Yao Kangde
Published: June 2012

To investigate the effects of reaction conditions on a intercalation between gelatin and montmorillonite (MMT) and thermodynamical impact of the intercalation, a series of gelatin/MMT hybrids were prepared by changing the reaction conditions (weight ratio of gelatin and MMT, pH, concentration of gelatin solution and MMT suspension, and reaction temperature).The hybrids were characterized by X‐ray diffraction, transmission electron microscopy, atomic absorption spectroscopy, and thermogravimetric analysis. The results showed the intercalation between gelatin and MMT, which was a faster process than the melt intercalation of some synthetic macromolecules such as polystyrene, achieved a thermodynamically stable state in 5 min. All the other reaction conditions, except reaction temperature, affected the intercalation between gelatin and MMT. The reaction was driven by enthalpy. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Reinforcement of biodegradable poly(butylene succinate) with low loadings of graphene oxide
Authors: Wan Chaoying , Chen Biqiong
Published: June 2012

The structure and mechanical properties of biodegradable poly(butylene succinate) (PBS)/graphene oxide (GO) composites were investigated. Chemically exfoliated GO nanosheets with an average lateral dimension of 1.50 (±0.15) μm and an average thickness of 1.18 (±0.09) nm were prepared by a modified Hummers method and used for reinforcement of PBS because of its abundant oxygen‐containing functional groups. The GO was dispersed as several layers in the PBS matrix through solution‐blending and compression‐molding methods that were characterized by transmission electron microscopy. The tensile strength, Young's modulus, and fracture energy of PBS were increased by 53, 70, and 100%, respectively, with an incorporation of 2.0 wt % of GO. The stiffness of PBS/GO composites was predicted using the Halpin–Tsai model and considering a two‐dimensional random dispersion of GO nanoplatelets in the PBS matrix and the effective volume fraction of the reinforcement. The crystallization temperature and crystallinity of PBS were increased by the addition of GO, indicating that it acts as a nucleating agent to facilitate the crystallization of PBS. The improvement of physical and mechanical properties of biodegradable PBS with the incorporation of low loadings of GO nanoplatelets further expands its industrial uses. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Carbon/polymer composite counter‐electrode application in dye‐sensitized solar cells
Authors: Zhang Xueni , Zhang Jing , Cui Yanzheng , Feng Jiangwei , Zhu Yuejin
Published: June 2012

Carbon black was embedded in mixtures of poly(ethylene oxide) and poly(vinylidene fluoride–hexafluoropropylene) to make a carbon/polymer composite slurry, which was deposited onto a transparent conducting glass substrate by a doctor‐blade coating for application in dye‐sensitized solar cells (DSSCs) as a counter‐electrode (CE) material. The experiments indicated that the photovoltaic parameters of the DSSCs were strongly dependent on the carbon concentration in the slurry. The device with a carbon CE whose mass ratio was 1 : 1 (mass ratio = carbon black mass to polymer mass) exhibited an overall energy conversion efficiency of 4.62%; this was comparable to that of a device with platinum as a CE (5.32%) under the same test conditions. The better electrocatalytic activity of CE‐1.0 (where 1.0 indicates the mass ratio of carbon black to polymer) for the reduction of triiodide resulted a higher performance of the DSSC with such a CE. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Modernization of an anatomy class: From conceptualization to implementation. A case for integrated multimodal–multidisciplinary teaching
Authors: Johnson Elizabeth O. , Charchanti Antonia V. , Troupis Theodore G.
Published: June 2012

It has become increasingly apparent that no single method for teaching anatomy is able to provide supremacy over another. In an effort to consolidate and enhance learning, a modernized anatomy curriculum was devised by attempting to take advantage of and maximize the benefits from different teaching methods. Both the more traditional approaches to anatomy teaching, as well as modern, innovative educational programs were embraced in a multimodal system implemented over a decade. In this effort, traditional teaching with lectures and dissection was supplemented with models, imaging, computer‐assisted learning, problem‐based learning through clinical cases, surface anatomy, clinical correlation lectures, peer teaching and team‐based learning. Here, we review current thinking in medical education and present our transition from a passive, didactic, highly detailed anatomy course of the past, to a more interactive, as well as functionally and clinically relevant anatomy curriculum over the course of a decade. Anat Sci Educ. © 2012 American Association of Anatomists.
Association of MMP3 and TIMP2 promoter polymorphisms with nonsyndromic oral clefts
Authors: Letra Ariadne , Silva Renato M. , Motta Luise G. , Blanton Susan H. , Hecht Jacqueline T. , Granjeirol Jose M. , Vieira Alexandre R.
Published: June 2012

BACKGROUND Oral clefts are common congenital anomalies and result from defects during embryogenesis. The complex etiology is evident by the number of genes and signaling pathways involved in craniofacial development. Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are responsible for tissue remodeling during craniofacial development. METHODS In this study, we investigated the association of polymorphisms in 14 biologically relevant MMP and TIMP genes in 494 individuals with oral clefts and 413 control individuals from Brazil. Genotypes were generated using Taqman chemistry. Analyses were performed using PLINK software. RESULTS Polymorphisms in MMP3 (rs522616) and TIMP2 (rs8179096) showed significant association with all cleft types (all clefts, cleft lip/palate, and cleft palate; p ≤ 0.002). An additional family‐based dataset (881 case‐parent trios) from the United States was used for confirmation of the association findings (p < 0.05). Analysis of gene‐gene interaction suggests that MMP3 and TIMP2 may interactively contribute to a cleft phenotype. CONCLUSIONS This study provides new evidence that variation in MMP3 may contribute to nonsyndromic oral clefts and further supports the involvement of TIMP2 as a cleft susceptibility gene. Although additional studies are still necessary to unveil the exact mechanism by which MMP3 and TIMP2 would contribute to a cleft phenotype, allelic polymorphisms in these genes and their interactions may partly explain the variance of individual susceptibility to oral clefts. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Newer anticonvulsants: Lamotrigine, topiramate and gabapentin
Authors: Holmes Lewis B. , Hernandez‐Diaz Sonia
Published: June 2012

BACKGROUND The second generation antiepileptic drugs (AEDs), which include lamotrigine, topiramate, and gabapentin, have been introduced during the past 20 years. Because the newer AEDs differ in their pharmacokinetics from the first generation AEDs, it is hoped that the second generation AEDs will be less teratogenic. METHODS The findings in pregnancy cohorts and case‐control studies concerning lamotrigine, topiramate and gabapentin‐exposed pregnancies have been analyzed. RESULTS The rate of all malformations in lamotrigine monotherapy‐exposed pregnancies has been between 2.0 and 5.6%, in comparison to baseline rates of 1.1 to 3.6% in two unexposed comparison groups. Compared to reference populations, a higher risk (0.4%) of isolated oral clefts has been observed in one cohort of 1562 lamotrigine‐exposed pregnancies, but the risk was lower (0.1%) in other studies. In topiramate‐exposed pregnancies, the rate of all malformations has been 4.2 to 4.9%, with an increase in oral clefts with and without other anomalies. The limited information available now for gabapentin has shown no evidence of teratogenicity. Concerning other developmental effects of these drugs, young children exposed to lamotrigine in utero have shown no deficits in cognitive function. Prenatal exposure to topiramate has been associated with an elevated frequency of small size for gestational age newborns. CONCLUSIONS The information available suggests an increased risk of oral clefts in infants exposed to topiramate, and perhaps lamotrigine, early in pregnancy, and of growth retardation for topiramate‐exposed infants. Larger sample sizes are needed to clarify the questions that have been raised. Birth Defects Research (Part A) 94:599–606, 2012. © 2012 Wiley Periodicals, Inc.
Selective ultrasound guided pectoral nerve targeting in breast augmentation: How to spare the brachial plexus cords?
Authors: Desroches Jean , Grabs Ursula , Grabs Detlev
Published: June 2012

Subpectoral breast augmentation surgery under regional anesthesia requires the selective neural blockade of the medial and lateral pectoral nerves to diminish postoperative pain syndromes. The purpose of this cadaver study is to demonstrate a reliable ultrasound guided approach to selectively target the pectoral nerves and their branches while sparing the brachial plexus cords. After evaluating the position and appearance of the pectoral nerves in 25 cadavers (50 sides), a portable ultrasound machine was used to guide the injection of 10 ml of 0.2% aqueous methylene blue solution in the pectoral region on both sides of three Thiel's embalmed cadavers using a single entry point—triple injection technique. This technique uses a medial to lateral approach with the entry point just medial to the pectoral minor muscle and three subsequent infiltrations: (1) deep lateral part of the pectoralis minor muscle, (2) between the pectoralis minor and major muscles, and (3) between the pectoralis major muscle and its posterior fascia under ultrasound visualization. Dissection demonstrates that the medial and lateral pectoral nerves were well stained while leaving the brachial plexus cords unstained. We show that 10 ml of an injected solution is sufficient to stain all the medial and lateral pectoral nerve branches without a proximal extension to the cords of the brachial plexus. Clin. Anat. 26:49–55, 2013. © 2012 Wiley Periodicals, Inc.
The anatomy of osteoarthritic joint pain
Authors: Witt Kevin L. , Vilensky Joel A.
Published: June 2012

The anatomical understanding of the pain generators in osteoarthritis (OA) is incomplete and the teaching about these pain generators in medical school anatomy/histology courses is minimal. This review covers the nociceptive innervation of synovial joints for the purposes of teaching. Studies that discuss the presence of neuropeptides involved in pain, such as Substance P (SP) and calcitonin‐gene‐related peptide, are the focus of this review. Nociceptive free‐nerve endings and SP staining nerves are found in the accessory ligaments, synovium, subchondral bone, menisci, and periosteum. The vasculature may also play a role in pain generation through vasospasm or ischemia, but this has yet to be proven. Joint denervation may relieve joint pain showing that it is indeed articular nerves that are carrying pain impulses but denervation does not identify the precise source of the pain. It remains unclear which of the anatomical loci of pain generation are primary in OA and if sources of pain vary in different patients and in different joints. Clin. Anat. 27:451–454, 2014. © 2012 Wiley Periodicals, Inc.
Epiphyseal maturity indicators at the knee and their relationship to chronological age: Results of an Irish population study
Authors: O'Connor Jean E. , Coyle Joseph , Spence Liam D. , Last Jason
Published: June 2012

Skeletal maturation is divisible to three main components; the time of appearance of an ossification center, its change in morphology and time of fusion to a primary ossification center. With regard to the knee, the intermediate period between appearance and fusion of the ossification centers extends over a period of greater than 10 years. This study aims to investigate radiographically the age at which morphological changes of the epiphyses at the knee occur in a modern Irish population. Radiographs of 221 subjects (137 males; 84 females) aged 9–19 years were examined. Seven nonmetric indicators of maturity were assessed using criteria modified from the Roche, Wainer, and Thissen method and Pyle and Hoerr's atlas of the knee. Reference charts are presented which display the timeline for each of the grades of development of the seven indicators. Mean age was found to increase significantly with successive grades of development of each of the seven indicators. A significant difference was noted between males and females at the same grade of development for six of the seven indicators. The narrowest age range reported for a single grade of development was 2.2 years for Grade 2 of development of the tibial tuberosity for males. The information on changing morphology of the epiphyses at the knee in the present study may provide an adjunct to methods used for evaluation of skeletal maturity before surgery for orthopedic disorders or to evaluate skeletal age in clinical scenarios where either delayed or precocious skeletal maturation is suspected. Clin. Anat. 26:755–767, 2013. © 2012 Wiley Periodicals, Inc.
Genetic and Biosynthetic Studies of the Fungal Prenylated Xanthone Shamixanthone and Related Metabolites in Aspergillus spp. Revisited
Authors: Simpson Thomas J.
Published: June 2012

Biosynthetic genes for the prenylated xanthone shamixanthone have been identified in the Aspergillus nidulans genome; based on assignment of putative functions from sequence analyses and selected gene deletions, a pathway was proposed leading from the anthraquinone emodin via the benzophenone carboxylic acid monodictyphenone and the xanthone emericellin to shamixanthone. Several aspects of this proposed pathway are inconsistent with previously identified biosynthetic intermediates: the anthraquinone chrysophanol and the benzophenone aldehyde derivatives arugosins F and A/B, isotopic labelling studies and chemical precedents. A new pathway is presented that provides a full rationale for the results of the gene deletion studies and reconciles them with previous biosynthetic results, and is in accord with established chemical and biosynthetic mechanisms. The importance of interpreting genetic information in terms of established biosynthetic events is discussed.
Characterization of the Suillus grevillei Quinone Synthetase GreA Supports a Nonribosomal Code for Aromatic α‐Keto Acids
Authors: Wackler Barbara , Lackner Gerald , Chooi Yit Heng , Hoffmeister Dirk
Published: June 2012

The gene greA was cloned from the genome of the basidiomycete Suillus grevillei. It encodes a monomodular natural product biosynthesis protein composed of three domains for adenylation, thiolation, and thioesterase and, hence, is reminiscent of a nonribosomal peptide synthetase (NRPS). GreA was biochemically characterized in vitro. It was identified as atromentin synthetase and therefore represents one of only a limited number of biochemically characterized NRPS‐like enzymes which accept an aromatic α‐keto acid. Specificity‐conferring amino acid residues—collectively referred to as the nonribosomal code—were predicted for the primary sequence of the GreA adenylation domain and were an unprecedented combination for aromatic α‐keto acids. Plausible support for this new code came from in silico simulation of the adenylation domain structure. According to the model, the predicted residues line the active site and, therefore, very likely contribute to substrate specificity.
Palladium‐Catalyzed Allylic Oxidation of Monoterpenic Alkenes with Molecular Oxygen
Authors: Bueno Aline C. , de Souza Ágatha O. , Gusevskaya Elena V.
Published: June 2012

Palladium/p‐benzoquinone‐catalyzed aerobic oxidation of biomass‐based feedstock substrates, that is, limonene and α‐terpineol, has been developed. The system promotes an efficient dioxygen‐coupled catalytic turnover in the absence of auxiliary redox‐active co‐catalysts. Important for flavor and pharmaceutical industries, monoterpenic allylic acetates have been obtained in good to excellent yields. The regioselectivity of the limonene oxidation can be controlled through the appropriate choice of ligands and reaction conditions, which enables the variation of organoleptic properties of the product mixtures. The catalytic system can be applied generally to the allylic oxidation of simple cycloalkenes with molecular oxygen, for example, cyclohexene gives the corresponding allylic acetate in a nearly quantitative yield.
The Effect of Alcohol Structures on the Interaction Mode with the Hexameric Capsule of Resorcin[4]arene
Authors: Slovak Sarit , Cohen Yoram
Published: June 2012

After more than a century of research on resorcin[4]arenes (1) it is clear that such systems form spontaneously [16(H2O)8]‐type hexameric capsules in wet, non‐polar, organic solvents. However, the interactions of these hexameric capsules with alcohols are far from being solved. Here we provide the results of an extensive study on the interaction of different alcohols with the hexameric capsules of resorcin[4]arene 1 a by focusing on the exchange of magnetization manifested in diffusion NMR measurements of such capsular systems. We found that some alcohols such as 2‐octyl‐1‐dodecanol and 1‐octadecanol do not interact with the hexamers of 1 a, whereas other alcohols such as 3‐ethyl‐3‐pentanol, 2‐ethyl‐1‐butanol and more act as simple guests and are simply encapsulated in the hexamers. Others alcohols such as 3‐pentanol, 2‐methyl‐1‐butanol and others, are part of the hexameric structure where they can exchange magnetization with alcohols in the bulk. The bulkier alcohols, due to an increase of the chain length or in branching, have a higher tendency to be encapsulated rather than being part of the hexameric capsule superstructure. This study demonstrate the unique information that diffusion NMR spectroscopy can provide on supramolecular systems in solution and on the precaution that should be exercised when analyzing diffusion NMR data of such dynamic supramolecular capsules.
Porous, Conductive Metal‐Triazolates and Their Structural Elucidation by the Charge‐Flipping Method
Authors: Gándara Felipe , Uribe‐Romo Fernando J. , Britt David K. , Furukawa Hiroyasu , Lei Liao , Cheng Rui , Duan Xiangfeng , O'Keeffe Michael , Yaghi Omar M.
Published: June 2012

A new family of porous crystals was prepared by combining 1H‐1,2,3‐triazole and divalent metal ions (Mg, Mn, Fe, Co, Cu, and Zn) to give six isostructural metal‐triazolates (termed MET‐1 to 6). These materials are prepared as microcrystalline powders, which give intense X‐ray diffraction lines. Without previous knowledge of the expected structure, it was possible to apply the newly developed charge‐flipping method to solve the complex crystal structure of METs: all the metal ions are octahedrally coordinated to the nitrogen atoms of triazolate such that five metal centers are joined through bridging triazolate ions to form super‐tetrahedral units that lie at the vertexes of a diamond‐type structure. The variation in the size of metal ions across the series provides for precise control of pore apertures to a fraction of an Angstrom in the range 4.5 to 6.1 Å. MET frameworks have permanent porosity and display surface areas as high as some of the most porous zeolites, with one member of this family, MET‐3, exhibiting significant electrical conductivity.
Synthesis and Study of Plasmon‐Induced Carrier Behavior at Ag/TiO2 Nanowires
Authors: Li Haiyan , Lu Wenbo , Tian Jingqi , Luo Yonglan , Asiri Abdullah M. , Al‐Youbi Abdulrahman O. , Sun Xuping
Published: June 2012

Nanocomposites of Ag/TiO2 nanowires with enhanced photoelectrochemical performance have been prepared by a facile solvothermal synthesis of TiO2 nanowires and subsequent photoreduction of Ag+ ions to Ag nanoparticles (AgNPs) on the TiO2 nanowires. The as‐prepared nanocomposites exhibited significantly improved cathodic photocurrent responses under visible‐light illumination, which is attributed to the local electric field enhancement of plasmon resonance effect near the TiO2 surface rather than by the direct transfer of charge between the two materials. The visible‐light‐driven photocatalytic performance of these nanocomposites in the degradation of methylene blue dye was also studied, and the observed improvement in photocatalytic activity is associated with the extended light absorption range and efficient charge separation due to surface plasmon resonance effect of AgNPs.
Theoretical Study of the Oxidation of Histidine by Singlet Oxygen
Authors: Méndez‐Hurtado Jefferson , López Ramón , Suárez Dimas , Menéndez María Isabel
Published: June 2012

Herein we present a theoretical study of the reaction of singlet oxygen with histidine performed both in the gas phase and in aqueous solution. The potential energy surface of the reactive system was explored at the B3LYP/cc‐pVTZ level of theory and the electronic energies were refined by means of single‐point CCSD(T)/cc‐pVTZ(‐f) calculations. Solvent effects were taken into account by using a solvent continuum model (COSMO) and by adding explicit water molecules. The results show that the first step in the reaction mechanism corresponds to a nearly symmetric Diels–Alder addition of the singlet oxygen molecule to the imidazole ring to yield an endoperoxide, in agreement with experimental evidence. The intermediate formed can evolve along two different reaction paths leading to two isomeric hydroperoxides and, eventually, to open‐chain or internally cyclised oxidised products. Water plays a significant role in stabilising the reaction structures by solvation and by acting as a bifunctional catalyst in the elimination/addition reaction steps. Our results explain why substituents at the N1‐imidazole ring can hamper the evolution of the initial endoperoxide and result in Gibbs energy barriers in solution similar to those experimentally measured and suggest a likely route to the formation of peptide aggregates during the oxidation of histidine by singlet molecular oxygen.
Chitosan Bio‐Based Organic–Inorganic Hybrid Aerogel Microspheres
Authors: El Kadib Abdelkrim , Bousmina Mosto
Published: June 2012

Recently, organic–inorganic hybrid materials have attracted tremendous attention thanks to their outstanding properties, their efficiency, versatility and their promising applications in a broad range of areas at the interface of chemistry and biology. This article deals with a new family of surface‐reactive organic–inorganic hybrid materials built from chitosan microspheres. The gelation of chitosan (a renewable amino carbohydrate obtained by deacetylation of chitin) by pH inversion affords highly dispersed fibrillar networks shaped as self‐standing microspheres. Nanocasting of sol–gel processable monomeric alkoxides inside these natural hydrocolloids and their subsequent CO2 supercritical drying provide high‐surface‐area organic–inorganic hybrid materials. Examples including chitosan–SiO2, chitosan–TiO2, chitosan–redox‐clusters and chitosan–clay‐aerogel microspheres are described and discussed on the basis of their textural and structural properties, thermal and chemical stability and their performance in catalysis and adsorption.
Porous Ni@Pt Core‐Shell Nanotube Array Electrocatalyst with High Activity and Stability for Methanol Oxidation
Authors: Ding Liang‐Xin , Li Gao‐Ren , Wang Zi‐Long , Liu Zhao‐Qing , Liu Hong , Tong Ye‐Xiang
Published: June 2012

Bimetallic core‐shell nanostructures are emerging as more important materials than monometallic nanostructures, and have much more interesting potential applications in various fields, including catalysis and electronics. In this work, we demonstrate the facile synthesis of core‐shell nanotube array catalysts consisting of Pt thin layers as the shells and Ni nanotubes as the cores. The porous Ni@Pt core‐shell nanotube arrays were fabricated by ZnO nanorod‐array template‐assisted electrodeposition, and they represent a new class of nanostructures with a high electrochemically active surface area of 50.08 m2 (g Pt)−1, which is close to the value of 59.44 m2 (g Pt)−1 for commercial Pt/C catalysts. The porous Ni@Pt core‐shell nanotube arrays also show markedly enhanced electrocatalytic activity and stability for methanol oxidation compared with the commercial Pt/C catalysts. The attractive performances exhibited by these prepared porous Ni@Pt core‐shell nanotube arrays make them promising candidates as future high‐performance catalysts for methanol electrooxidation. The facile method described herein is suitable for large‐scale, low‐cost production, and significantly lowers the Pt loading, and thus, the cost of the catalysts.
Isostructural M2L4 Molecular Capsules with Anthracene Shells: Synthesis, Crystal Structures, and Fluorescent Properties
Authors: Li Zhiou , Kishi Norifumi , Yoza Kenji , Akita Munetaka , Yoshizawa Michito
Published: June 2012

An isostructural series of M2L4 molecular capsules quantitatively self‐assembled from two MII ions (M=Zn, Cu, Pt, Pd, Ni, Co, and Mn) and four bent ligands with embedded anthracene fluorophores. X‐ray crystallographic analysis (for M=Zn, Cu, Ni, and Pd) confirmed the formation of closed‐shell structures in which the large interior cavities inside the molecular capsules (about 1 nm) were shielded by eight anthracene panels. Analysis of the ZnII and CuII structures showed the inclusion of an unusual triad guest cluster; four MeCN molecules, one water molecule, and one CF3SO3− ion were located inside the cavities. Full characterization by NMR spectroscopy and MS (ESI‐TOF) demonstrated that the molecular capsules were quite stable and persist in solution. The fluorescence properties of the isostructural capsules were strongly dependent on the identity of the metal species: the ZnII capsule emitted strong blue fluorescence with a high quantum yield (Φ=0.8), in sharp contrast to the weakly emissive NiII and MnII capsules and the completely non‐emissive PdII, PtII, and CoII capsules. On the other hand, the CuII capsule exhibited solvatochromism and solvent‐dependent emission behavior; blue emission of the capsule was “on” in DMSO but “off” in MeCN.
A Flexible Copper(I)‐Complexed [4]Rotaxane Containing Two Face‐to‐Face Porphyrinic Plates that Behaves as a Distensible Receptor
Authors: Roche Cécile , Sour Angélique , Sauvage Jean‐Pierre
Published: June 2012

A new cyclic [4]rotaxane composed of two flexible bis‐macrocycles and two rigid axles is described. Each bis‐macrocycle consists of two rings attached to antipodal meso positions of a central Zn porphyrin through single CC bonds. Each ring incorporates a 2,9‐diphenyl‐1,10‐phenanthroline chelation site. The axles contain two coplanar bidentate sites derived from the 2,2′‐bipyridine motif. The building blocks were assembled by using a one‐pot threading‐and‐stoppering reaction, which afforded the [4]rotaxane in 50 % yield. The “gathering‐and‐threading” effect of copper(I) was utilised in the formation of a [4]pseudorotaxane, which was immediately converted to the corresponding [4]rotaxane by a quadruple CuAAC stoppering reaction. The rotaxane contains two face‐to‐face zinc porphyrins, which allowed the coordination of ditopic guest substrates. The rotaxane host showed remarkable flexibility and was able to adjust its conformation to the guest size. It can be distended and accommodate rod‐like guests of 2.6 to 15.8 Å in length.
C3‐Symmetric Trisimidazoline‐Catalyzed Enantioselective Bromolactonization of Internal Alkenoic Acids
Authors: Murai Kenichi , Nakamura Akira , Matsushita Tomoyo , Shimura Masato , Fujioka Hiromichi
Published: June 2012

A method for conducting enantioselective bromolactonization reactions of trisubstituted alkenoic acids, using the C3‐symmetric trisimidazoline 1 and 1,3‐dibromo‐5,5‐dimethyl hydantoin as a bromine source, has been developed. The process generates chiral δ‐lactones that contain a quaternary carbon. The results of studies probing geometrically different olefins show that (Z)‐olefins rather than (E)‐olefins are favorable substrates for the process. The method is not only applicable to acyclic olefin reactants but can also be employed to transform cyclic trisubstituted olefins into chiral spirocyclic lactones. Finally, the synthetic utility of the newly developed process is demonstrated by its application to a concise synthesis of tanikolide, an antifungal marine natural product.
Expanding the Scope of Arylsulfonylacetylenes as Alkynylating Reagents and Mechanistic Insights in the Formation of Csp2Csp and Csp3Csp Bonds from Organolithiums
Authors: García Ruano José Luis , Alemán José , Marzo Leyre , Alvarado Cuauhtémoc , Tortosa Mariola , Díaz‐Tendero Sergio , Fraile Alberto
Published: June 2012

We describe the unexpected behavior of the arylsulfonylacetylenes, which suffer an “anti‐Michael” addition of organolithiums producing their alkynylation under very mild conditions. The broad scope, excellent yields, and simplicity of the experimental procedure are the main features of this methodology. A rational explanation of all these results can be achieved by theoretical calculations, which suggest that the association of the organolithiums to the electrophile is a previous step of their intramolecular attack and is responsible for the unexpected “anti‐Michael” reactions observed for substituted sulfonylacetylenes.
Enhanced Red Emission from GdF3:Yb3+,Er3+ Upconversion Nanocrystals by Li+ Doping and Their Application for Bioimaging
Authors: Yin Wenyan , Zhao Lina , Zhou Liangjun , Gu Zhanjun , Liu Xiaoxiao , Tian Gan , Jin Shan , Yan Liang , Ren Wenlu , Xing Gengmei , Zhao Yuliang
Published: June 2012

Under 980 nm near‐infrared (NIR) excitation, upconversion luminescent (UCL) emission of GdF3:Yb,Er upconversion nanoparticles (UCNPs) synthesized by a simple and green hydrothermal process can be tuned from yellow to red by varying the concentration of dopant Li+ ions. A possible mechanism for enhanced red upconverted radiation is proposed. A layer of silica was coated onto the surface of GdF3:Yb,Er,Li UCNPs to improve their biocompatibility. The silica‐coated GdF3:Yb,Er,Li UCNPs show great advantages in cell labeling and in vivo optical imaging. Moreover, GdF3 UCNPs also exhibited a positive contrast effect in T1‐weighted magnetic resonance imaging (MRI). These results suggest that the GdF3 UCNPs could act as dual‐modality biolabels for optical imaging and MRI.
Metal Ions Induce Growth and Magnetism Alternation of α‐Fe2O3 Crystals Bound by High‐Index Facets
Authors: Liu Rongmei , Jiang Yuanwen , Fan Hao , Lu Qingyi , Du Wei , Gao Feng
Published: June 2012

In this study, quasi‐cubic and hexagonal bipyramid α‐Fe2O3 polyhedrons with high‐index facets exposed were controllably synthesized by applying metal ions Zn2+ or Cu2+ as structure‐directing agents. The growth of the α‐Fe2O3 nanostructures with high‐index facets were induced by metal ions without the addition of any other surfactants. The quasi‐cubic form controlled by Zn2+ looks like a cube but has an angle of approximately 86° bound by (012), (10‐2), and (1‐12) facets, whereas the hexagonal bipyramid form controlled by Cu2+ has a sixfold axis bound by {012} facets. Magnetic measurements confirm that these two kinds of nanocrystals display shape‐ and surface‐dependent magnetic behaviors. The hexagonal bipyramid iron oxide nanocrystals show a lower Morin transition temperature of 240 K and might be spin‐canted ferromagnetically controlled at room temperature, and the ferromagnetism disappears at low temperature. The quasi‐cubic nanocrystals have a splitting between FC curve and ZFC curve from the highest experimental temperature and no Morin transformation occurs; this indicates that they would be defect ferromagnetically controlled at low temperature. The reported metal‐ion‐directing technique could provide a universal method for shape‐ and surface‐controlled synthesis of nanocrystals with high‐index facets exposed.
ChemInform Abstract: Pronounced Site Preference and Mixed Dinuclear Dichalcogenide Anions (SSe)2‐ in Ternary Lanthanum Sulfide Selenides — The Solid Solution LaS1.9—LaSe1.9.
Authors: Bartsch Christian , Doert Thomas
Published: June 2012

Ternary lanthanum sulfide selenides LaS1.9‐xSex (0 < x < 1.9) are prepared by reaction of the elements in a KBr flux (carbon crucibles, 850 °C, 7 d).
ChemInform Abstract: Ternary Compound CuInTe2: A Promising Thermoelectric Material with Diamond‐Like Structure.
Authors: Liu Ruiheng , Xi Lili , Liu Huili , Shi Xun , Zhang Wenqing , Chen Lidong
Published: June 2012

CuInTe2 is synthesized from the elements (evacuated silica tube, 900 °C, 12 h; annealing at 650 °C) and characterized by powder XRD and thermoelectric measurements.
ChemInform Abstract: Gaseous Vanadium Molybdate and Tungstates: Thermodynamic Properties and Structures.
Authors: Gunina Anastasia O. , Lopatin Sergey I. , Shugurov Sergey M.
Published: June 2012

Thermodynamic properties of gaseous V—Mo—O‐ and V—W—O‐containing species such as the standard formation enthalpies of gaseous VMoO4, VWO3, and VWO4 are determined by high‐temperature mass spectrometry.
ChemInform Abstract: Highly Selective Sorption of Small Polar Molecules by a Nonporous Ionic Crystal of a Lacunary Keggin‐Type Heteropoly Anion and Alkali Metal Cations.
Authors: Miura Yu‐ki , Kamiya Yuichi
Published: June 2012

Cs6.1K0.9[PW11O39] is synthesized from an aqueous solution of K7PW11O39 and CsCl (room temperature, 1 d, followed by treatment at 473 K for 2 h).
ChemInform Abstract: An Easy Access to Nanocrystalline Alkaline Earth Metal Fluorides — Just by Shaking.
Authors: Dreger M. , Scholz G. , Kemnitz E.
Published: June 2012

Nanocrystalline alkaline earth metal fluorides MF2 (M: Mg, Ca, Sr, Ba) are mechanochemically synthesized by high energy ball milling of mixtures of the metal sources (acetates, carbonates, hydroxides, alkoxides) and NH4F as fluorinating agent.
ChemInform Abstract: PbPt(IO3)6(H2O): A New Polar Material with Two Types of Stereoactive Lone‐Pairs and a Very Large SHG Response.
Authors: Sun Chuan‐Fu , Hu Chun‐Li , Mao Jiang‐Gao
Published: June 2012

The novel title compound is hydrothermally synthesized from a mixture of PbCl2, Pt(acac)2, I2O5, and H2O (autoclave, 190 °C, 4 d, 80% yield).
ChemInform Abstract: Hydrotrope Induced Catalysis in Water: A Clean and Green Approach for the Synthesis of Medicinally Relevant Bis(indolyl)methanes and 2‐Aryl Benzimidazoles.
Authors: Kamble Santosh , Rashinkar Gajanan , Kumbhar Arjun , Salunkhe Rajashri
Published: June 2012

The reaction is conducted in environmentally benign water, whereas the aqueous phase containing the mediating hydrotrope can be recycled.
ChemInform Abstract: Synthesis and Evaluation of Antitubercular and Antibacterial Activities of New 4‐(2,6‐Dichlorobenzyloxy)phenyl Thiazole, Oxazole and Imidazole Derivatives. Part 2.
Authors: Lu Xiaoyun , Liu Xiaobo , Wan Baojie , Franzblau Scott G. , Chen Lili , Zhou Changlin , You Qidong
Published: June 2012

A series of novel 4‐(2,6‐dichlorobenzyloxy)phenyl substituted thiazole, oxazole and imidazole derivatives are synthesized and screened in vitro for their antitubercular (H37Rv) and antibacterial activities.
ChemInform Abstract: Metal‐Free, Visible‐Light Mediated Direct C—H Arylation of Heteroarenes with Aryl Diazonium Salts.
Authors: Hari Durga Prasad , Schroll Peter , Koenig Burkhard
Published: June 2012

Under optimized conditions using eosin Y as a photoredox catalyst and green light LED irradiation, a variety of aryldiazonium salts can be applied to the arylation of furan, thiophenes, an N‐protected pyrrole, and nitrobenzene.
ChemInform Abstract: Dual‐Functional Click‐Triazole: A Metal Chelator and Immobilization Linker for the Construction of a Heterogeneous Palladium Catalyst and Its Application for the Aerobic Oxidation of Alcohols.
Authors: Zhang Guofu , Wang Yong , Wen Xin , Ding Chengrong , Li Ying
Published: June 2012

A novel SBA‐15 supported Pd‐catalyst containing a 2‐pyridyl‐1,2,3‐triazole ligand framework is prepared.
ChemInform Abstract: Convenient Chlorination of Some Special Aromatic Compounds Using N‐Chlorosuccinimide.
Authors: Gan Zongjie , Hu Bin , Song Qiao , Xu Yungen
Published: June 2012

The use of NCS in acetonitrile or DMF allows the regioselective synthesis of monochlorinated products from different arenes or N‐heterocycles.
ChemInform Abstract: Practical Synthesis of Aromatic Nitriles via Gallium‐Catalyzed Electrophilic Cyanation of Aromatic C—H Bonds.
Authors: Okamoto Kazuhiro , Watanabe Masahito , Murai Masahito , Hatano Ryo , Ohe Kouichi
Published: June 2012

The cyanation of heteroarenes (I) and arenes (IV) proceeds with very high regioselectivity to afford single products (III) and (V), whilst the reaction of biaryl (VI) affords a mixture of isomers (VII) and (VIII).
ChemInform Abstract: Enantioselective Organocatalytic α‐Alkylation of Ketones by SN1‐Type Reaction of Alcohols.
Authors: Trifonidou Maria , Kokotos Christoforos G.
Published: June 2012

The first examples of a non‐ionic liquid‐type organocatalyst for the “difficult” α‐alkylation of ketones is presented.
ChemInform Abstract: Optimized Reaction Conditions for the Cross‐Metathesis of Methyl Oleate and Oleylamine with Ethyl Acrylate.
Authors: Abbas Mudassar , Slugovc Christian
Published: June 2012

Protection of the amino group is essential for the successful cross‐metathesis of oleylamine.
ChemInform Abstract: SBA‐15‐Functionalized Sulfonic Acid Confined Acidic Ionic Liquid: A Powerful and Water‐Tolerant Catalyst for Solvent‐Free Esterifications.
Authors: Karimi Babak , Vafaeezadeh Majid
Published: June 2012

Incorporating the hydrophobic Broensted acid ionic liquid [C8‐mim]HSO4 inside the nanospaces of SBA‐15 functionalized propylsulfuric acid leads to a hydrophobic super Broensted acid which shows excellent catalytic performance in the direct esterification of alcohols and carboxylic acids at ambient temperature.
ChemInform Abstract: Amberlyst‐15 as a Recyclable Heterogeneous Catalyst for Synthesis of N‐tert‐Butylamides via Ritter‐Type Reaction.
Authors: Mokhtary Masoud , Goodarzi Gholamreza
Published: June 2012

Ester (II) can be used for the formation of various amides from aliphatic and aromatic nitriles.
ChemInform Abstract: Gold‐Catalyzed Oxyarylation of Styrenes and Mono‐ and gem‐Disubstituted Olefins Facilitated by an Iodine(III) Oxidant.
Authors: Ball Liam T. , Lloyd‐Jones Guy C. , Russell Christopher A.
Published: June 2012

A new iodine(III) reagent is used as the oxidant for gold‐catalyzed oxyarylation reactions of various olefins.
ChemInform Abstract: One‐Pot Synthesis of Telluroketene Acetals and Haloketene Acetals Using sp2 Geminated Hetero Organobismetallic Intermediates.
Authors: Guerrero Palimecio G. Jr. , de Oliveira Paulo R. , Baroni Adriano C. M. , Marques Francisco A. , Labes Ricardo , Dabdoub Miguel J.
Published: June 2012

The 1,1,‐bismetallic precursors are prepared according to a literature procedure.
ChemInform Abstract: A Generalized Approach for Iron Catalyzed Chemo‐ and Regioselective Formation of anti‐Markovnikov Acetals from Styrene Derivatives.
Authors: Chowdhury Abhishek Dutta , Lahiri Goutam Kumar
Published: June 2012

Ph‐I(O‐Ac)2 in the presence of catalytic amounts of Fe(BF4)2 and pyridine‐2,6‐dicarboxylic acid efficiently and selectively promotes the transformation of styrenes into anti‐Markovnikov dialkyl acetals under mild conditions.
ChemInform Abstract: Synthesis of 2‐(1‐Aryl‐2‐nitroethyl)‐3‐arylaminoacrylates via Domino Reaction of Arylamines, Methyl Propiolate, and Nitrostyrenes.
Authors: Sun Jing , Sun Yan , Gao Hong , Yan Chao‐Guo
Published: June 2012

The reaction offers an efficient stereoselective protocol for the preparation of highly functionalized subunits of type (IV).
ChemInform Abstract: Synthesis of Difluoromethyl‐Containing α‐Acyloxycarboxamide Derivatives Through a Passerini Reaction and Desulfonylation.
Authors: Wu Jingjing , Zhao Wenwen , Cao Song
Published: June 2012

Desulfuration of amides (IV), obtained by Passerini reaction of phenylsulfanyl‐protected isonitrile (I), proceeds efficiently via the corresponding sulfones (V).
ChemInform Abstract: N‐Methyl‐N‐(2‐phenylethenyl)trifluoromethanesulfonamide.
Authors: Shainyan B. A. , Ushakova I. V.
Published: June 2012

Title compound (V), the first representative of an N‐alkenyl‐substituted trifluoromethanesulfonamide derivative, is obtained in three steps starting from N‐(2‐phenylethyl)‐trifluoromethanesulfonamide (I).
ChemInform Abstract: Extrusion of CO from Aryl Ketones: Rhodium(I)‐Catalyzed C—C Bond Cleavage Directed by a Pyridine Group.
Authors: Lei Zhi‐Quan , Li Hu , Li Yang , Zhang Xi‐Sha , Chen Kang , Wang Xin , Sun Jian , Shi Zhang‐Jie
Published: June 2012

An anchimeric assistance of an N‐containing directing group, generally 2‐pyridyl is critical for the success of the double C—C cleavage process.
ChemInform Abstract: An Efficient Synthesis of 2‐Aryl‐1,4‐diketones via Hydroacylation of Enones.
Authors: Reddy P. Lakshmi , Kumar K. Praveen , Satyanarayana S. , Narender R. , Reddy B. V. Subba
Published: June 2012

SNB is found to be the most efficient catalyst component.
ChemInform Abstract: Application of Nickel Complexes Modified by Tridentate O,N,O′‐Ligands as Precatalysts in Nickel‐Catalyzed C(sp2)—C(sp3) Bond Formations.
Authors: Someya Chika I. , Inoue Shigeyoshi , Krackl Sebastian , Irran Elisabeth , Enthaler Stephan
Published: June 2012

New Ni catalysts containing highly flexible hexafluoroacetylacetonate‐based ligands are prepared and tested in the coupling reaction of benzylzinc bromide (I) with aryl halides (II) and (IV).
ChemInform Abstract: Synthesis and Antimicrobial Evaluation of Some New Cyclooctanones and Cyclooctane‐Based Heterocycles.
Authors: Ali Korany A. , Hosni Hanaa M. , Ragab Eman A. , Abd El‐Moez Sherein I.
Published: June 2012

A variety of new aminomethylenecyclooctane derivatives and cyclooctane‐based heterocycles with pyrazole, isoxazole, pyrimidine, pyrazolopyrimidine, triazolopyrimidine, and imidazopyrimidine rings is synthesized via reactions of cyclooctanone (III) with appropriate nitrogen nucleophiles.
ChemInform Abstract: Catalytic C—H Arylation of Unactivated Heteroaromatics with Aryl Halides by Cobalt Porphyrin.
Authors: Qian Ying Ying , Wong Ka Lai , Zhang Meng Wen , Kwok Tsz Yiu , To Ching Tat , Chan Kin Shing
Published: June 2012

The cobalt porphyrin catalyzed synthesis of heterobiaryls is proposed to proceed through a homolytic aromatic substitution.
ChemInform Abstract: Mild Synthetic Approach to Novel Indole‐1‐carbinols and Preliminary Evaluation of Their Cytotoxicity in Hepatocarcinoma Cells.
Authors: Zedda Gloria , Simbula Gabriella , Begala Michela , Pibiri Monica , Floris Costantino , Casu Mariano , Casu Laura , Tocco Graziella
Published: June 2012

The title compounds (III) and (V) are obtained in an one‐pot solvent‐free reaction of indoles with paraformaldehyde in the presence of an excess of CaO, MgO, ZnO, or TiO2.
ChemInform Abstract: Silica Sulfuric Acid, an Efficient and Recyclable Solid Acid Catalyst for the Synthesis of 4,4′‐(Arylmethylene)bis(1H‐pyrazol‐5‐ols).
Authors: Niknam Khodabakhsh , Mirzaee Salimeh
Published: June 2012

The catalyst can be reused 8 times without appreciable loss in activity.
ChemInform Abstract: Synthesis of Optically Active Oxazoline Derivatives via Catalytic Asymmetric Desymmetrization of 1,3‐Diols.
Authors: Tsuda Yutaro , Kuriyama Masami , Onomura Osamu
Published: June 2012

The procedure is applicable to various amino‐1,3‐diols tolerating (hetero)aryl substituents bearing electron‐donating as well as electron‐withdrawing groups, and moieties.
ChemInform Abstract: Palladium‐Catalyzed N‐Arylation of 2‐Aminothiazoles.
Authors: McGowan Meredeth A. , Henderson Jaclyn L. , Buchwald Stephen L.
Published: June 2012

Optimized conditions are elaborated for the different types of substrates.
ChemInform Abstract: Synthesis of Some New S‐Alkylated 1,2,4‐Triazoles, Their Mannich Bases and Their Biological Activities.
Authors: Alam Mohammad Mahboob , Nazreen Syed , Haider Saqlain , Shafi Syed , Yar Mohammad Shahar , Hamid Hinna , Alam Mohammad Sarwar
Published: June 2012

A variety of new S‐alkylated triazoles (IX) (19 examples) and related Mannich bases (XII) are synthesized and evaluated for their pharmacological activities.
ChemInform Abstract: Unusual Cu(I)‐Catalyzed 1,3‐Dipolar Cycloaddition of Acetylenic Amides: Formation of Bistriazoles.
Authors: Kwon Mihyun , Jang Yujin , Yoon Sunyoung , Yang Dongsik , Jeon Heung Bae
Published: June 2012

The attempt to prepare exclusively triazoles (III) in the presence of (iPr2)N‐Et and CuI in DMF fails.
ChemInform Abstract: Amine‐Catalyzed Formal [3 + 3] Annulations of 2‐(Acetoxymethyl)buta‐2,3‐dienoate with Sulfur Ylides: Synthesis of 4H‐Pyrans Bearing a Vinyl Sulfide Group.
Authors: Li Kun , Hu Jian , Liu Hui , Tong Xiaofeng
Published: June 2012

A DABCO‐catalyzed annulation of allenoate (I) and ketone‐stabilized ylides (II), (IV), and (VI), in which the sulfur atom of the ylide is transferred into the resulting 4H‐pyran is reported.
ChemInform Abstract: Facile Syntheses of 3‐Hydroxyflavones.
Authors: Gunduz Simay , Goren Ahmet C. , Ozturk Turan
Published: June 2012

Compared to known four‐step reactions requiring more than 100 h, the new synthesis proceeds without any side products within 5 h.
ChemInform Abstract: Cu/SiO2‐Catalyzed One‐Pot Synthesis of 12‐Aryl‐8,9,10,12‐tetrahydrobenzo[α]xanthen‐11‐ones under Solvent‐Free Conditions.
Authors: Oskooie Hossein A. , Heravi Majid M. , Karimi Narges , Kohansal Golnaz
Published: June 2012

Cu—SiO2 promotes the three‐component reaction of aromatic aldehydes, β‐naphthol, and dimedone to give title compounds of type (IV).
ChemInform Abstract: One‐Pot Efficient Green Synthesis of Spirooxindole‐Annulated Thiopyran Derivatives via Knoevenagel Condensation Followed by Michael Addition.
Authors: Majumdar K. C. , Ponra Sudipta , Nandi Raj Kumar
Published: June 2012

The three‐component reaction affords the title compounds (IV) in a short reaction time.
ChemInform Abstract: Simple, Three‐Component, Highly Efficient Green Synthesis of Thiazolo[3,2‐a]pyridine Derivatives under Neat Conditions.
Authors: Mekheimer Ramadan Ahmed , Hilmy Noha Mohamed , Abdel Hameed Afaf , Dacrory Sawsan , Sadek Kamal Usef
Published: June 2012

Changing the molar ratios, compounds (IV) or (V) become the main product.
ChemInform Abstract: Synthesis of Dihydropyrimidinones via Biginelli Multi‐Component Reaction.
Authors: Narahari Srinivasa Reddy , Reguri Buchi Reddy , Gudaparthi Omprakash , Mukkanti K.
Published: June 2012

The mild conditions can also be applied to cyclic ketones such as tetralone (VIII).
ChemInform Abstract: A New Benzotriazole‐Mediated Stereoflexible Gateway to Hetero‐2,5‐diketopiperazines.
Authors: Monbaliu Jean‐Christophe M. , Hansen Finn K. , Beagle Lucas K. , Panzner Matthew J. , Steel Peter J. , Todadze Ekaterina , Stevens Christian V. , Katritzky Alan R.
Published: June 2012

A convenient, versatile, and flexible benzotriazole‐mediated methodology for the synthesis of proline‐containing hetero‐2,5‐diketopiperazines is reported.
ChemInform Abstract: Sodium Cyanoborohydride‐Mediated Direct Conversion of Some Heterocyclic Aldehydes to Esters.
Authors: Goswami Shyamaprosad , Hazra Anita , Goh Jia Hao , Fun Hoong‐Kun
Published: June 2012

An exceptional oxidizing behavior of sodium cyanoborohydride is observed where electron‐withdrawing heterocyclic aldehydes are directly converted to their corresponding esters.
ChemInform Abstract: Stereocontrolled Oxyselenation Studies on 1,4‐Dihydropyridines: Synthesis of trans‐2‐Hydroxy (or Alkoxy) 3‐Phenylseleno‐1,2,3,4‐tetrahydropyridines.
Authors: Kumar Rakesh , Kumar Dhiraj , Prasad Ashok K.
Published: June 2012

Regio‐ and diastereoselective oxyselenenylations of 1,4‐dihydropyridines in the presence of water and alcohols, resp., are described.
ChemInform Abstract: Synthesis and Evaluation of Cytotoxic Effects of Novel α‐Methylenelactone Tetracyclic Diterpenoids.
Authors: Zhang Da‐yong , et al. et al.
Published: June 2012

Compounds (Ia)—(Ic) show significant cytotoxicity superior to the positive control doxorubicin hydrochloride against MDA‐MB‐231, K562, and HepG2 cell lines.