bluuebunny/crossref_metadata_2025 huggingface dataset:
Organo‐Iodine(III)‐Catalyzed Oxidative Phenol–Arene and Phenol–Phenol Cross‐Coupling Reaction
Authors: Morimoto Koji , Sakamoto Kazuma , Ohshika Takao , Dohi Toshifumi , Kita Yasuyuki
Published: February 2016

The direct oxidative coupling reaction has been an attractive tool for environmentally benign chemistry. Reported herein is that the hypervalent iodine catalyzed oxidative metal‐free cross‐coupling reaction of phenols can be achieved using Oxone as a terminal oxidant in 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP). This method features a high efficiency and regioselectivity, as well as functional‐group tolerance under very mild reaction conditions without using metal catalysts.
A General and Mild Approach to Controllable Preparation of Manganese‐Based Micro‐ and Nanostructured Bars for High Performance Lithium‐Ion Batteries
Authors: Ma Guo , Li Sheng , Zhang Weixin , Yang Zeheng , Liu Shulin , Fan Xiaoming , Chen Fei , Tian Yuan , Zhang Weibo , Yang Shihe , Li Mei
Published: February 2016

One‐dimensional (1D) micro‐ and nanostructured electrode materials with controllable phase and composition are appealing materials for use in lithium‐ion batteries with high energy and power densities, but they are challenging to prepare. Herein, a novel ethanol–water mediated co‐precipitation method by a chimie douce route (synthesis conducted under mild conditions) has been exploited to selectively prepare an extensive series of manganese‐based electrode materials, manifesting the considerable generalizability and efficacy of the method. Moreover, by simply tuning the mixed solvent and reagents, transition metal oxide bars with differing aspect ratios and compositions were prepared with an unprecedented uniformity. Application prospects are demonstrated by Li‐rich 0.5 Li2MnO3⋅0.5 LiNi1/3Co1/3Mn1/3O2 bars, which demonstrate excellent reversible capacity and rate capability thanks to the steerable nature of the synthesis and material quality. This work opens a new route to 1D micro‐ and nanostructured materials by customizing the precipitating solvent to orchestrate the crystallization process.
The Uptake and Assembly of Alkanes within a Porous Nanocapsule in Water: New Information about Hydrophobic Confinement
Authors: Kopilevich Sivil , Gottlieb Hugo , Keinan‐Adamsky Keren , Müller Achim , Weinstock Ira A.
Published: February 2016

In Nature, enzymes provide hydrophobic cavities and channels for sequestering small alkanes or long‐chain alkyl groups from water. Similarly, the porous metal oxide capsule [{MoVI6O21(H2O)6}12{(MoV2O4)30(L)29(H2O)2}]41− (L=propionate ligand) features distinct domains for sequestering differently sized alkanes (as in Nature) as well as internal dimensions suitable for multi‐alkane clustering. The ethyl tails of the 29 endohedrally coordinated ligands, L, form a spherical, hydrophobic “shell”, while their methyl end groups generate a hydrophobic cavity with a diameter of 11 Å at the center of the capsule. As such, C7 to C3 straight‐chain alkanes are tightly intercalated between the ethyl tails, giving assemblies containing 90 to 110 methyl and methylene units, whereas two or three ethane molecules reside in the central cavity of the capsule, where they are free to rotate rapidly, a phenomenon never before observed for the uptake of alkanes from water by molecular cages or containers.
One‐Electron Oxidation of [M(PtBu3)2] (M=Pd, Pt): Isolation of Monomeric [Pd(PtBu3)2]+ and Redox‐Promoted C−H Bond Cyclometalation
Authors: Troadec Thibault , Tan Sze‐yin , Wedge Christopher J. , Rourke Jonathan P. , Unwin Patrick R. , Chaplin Adrian B.
Published: February 2016

Oxidation of zero‐valent phosphine complexes [M(PtBu3)2] (M=Pd, Pt) has been investigated in 1,2‐difluorobenzene solution using cyclic voltammetry and subsequently using the ferrocenium cation as a chemical redox agent. In the case of palladium, a mononuclear paramagnetic PdI derivative was readily isolated from solution and fully characterized (EPR, X‐ray crystallography). While in situ electrochemical measurements are consistent with initial one‐electron oxidation, the heavier congener undergoes C−H bond cyclometalation and ultimately affords the 14 valence‐electron PtII complex [Pt(κ2PC‐PtBu2CMe2CH2)(PtBu3)]+ with concomitant formation of [Pt(PtBu3)2H]+.
Acid–Base‐Triggered Structural Transformation of a Polyoxometalate Core Inside a Dodecahedrane‐like Silver Thiolate Shell
Authors: Liu Hong , Song Chao‐Yu , Huang Ren‐Wu , Zhang Yu , Xu Hong , Li Mei‐Jia , Zang Shuang‐Quan , Gao Guang‐Gang
Published: February 2016

Self‐assembly of metavanadate and organosilver(I) salts leads to a novel dodecahedrane‐like [Ag30(tBuS)20]10+ silver(I) thiolate nanocage that tightly wraps an unusual C2h polyoxovanadate anion. The polyoxovanadate core undergoes transformation to a D3d configuration upon acidification, and reverts back to its original C2h structure upon addition of base. Chromism was observed for the silver(I) thiolate cluster during the configurational change of the central polyoxovanadate core; the color of the solution changes reversibly from green to dark yellow. This work represents the first reported example of chromic polyoxometalate‐templated silver(I) thiolate shells that respond to external acid–base stimuli. It also represents an important advance in providing crystallographic proof that structural transformations occur in a nanoscale core–shell cluster.
Copper‐Catalyzed Insertion into Heteroatom–Hydrogen Bonds with Trifluorodiazoalkanes
Authors: Hyde Stephen , Veliks Janis , Liégault Benoît , Grassi David , Taillefer Marc , Gouverneur Véronique
Published: February 2016

Copper‐catalyzed Si−H, B−H, P−H, S−H, and N−H insertion reactions of 2,2,2‐trifluoro‐1‐diazoethane and 1‐aryl 2,2,2‐trifluorodiazoethanes generated a large number of new fluorine‐containing chemical entities for medicinal chemists. With selected Si−H and B−H insertion reactions, we demonstrate successful extension to asymmetric catalysis.
Heterogenization of titanium(IV) complexes with amine bis(phenolate) ligands onto SBA‐15: exploring their catalytic epoxidation and electrochemical behaviour
Authors: Hierro Isabel del , Pérez Yolanda , Fajardo Mariano
Published: February 2016

This paper describes the synthesis and characterization of titanium catalysts supported onto SBA‐15 via chemical bonding. This was done by first modifying the support with amine bis(phenol) groups as functional linkers and hexamethyldisilizane as capping agent to mask the remaining silanol groups on the silica surface. Finally, titanium tetraisopropoxide was immobilized by reaction with the modified SBA‐15. All the materials were characterized using X‐ray diffraction, X‐ray fluorescence, nitrogen adsorption‐desorption, Fourier transform infrared, UV‐visible diffuse reflectance and solid‐state nuclear magnetic resonance spectroscopies, and solid‐state electrochemical techniques. The titanium materials were tested as cyclohexene epoxidation catalysts. The stability and reusability of the catalysts were also examined using voltammetry measurements. Copyright © 2016 John Wiley & Sons, Ltd.
Wetting behavior of polymer melts on coated and uncoated tool steel surfaces
Authors: Zitzenbacher Gernot , Huang Zefeng , Längauer Manuel , Forsich Christian , Holzer Clemens
Published: February 2016

The wettability of steel and coatings used for tools and screws in polymer processing is often determined at room temperature. However, it has to be taken into account that polymeric materials are processed at higher temperatures. Contact angle measurements of melted PP, HDPE, PMMA, and PA 6.6 on steel and on TiN, TiAlN, CrN, DLC, and PTFE were performed in this work to investigate the wetting behavior under closer‐to‐processing conditions. The contact angle is dependent on time and the ambient atmosphere. Oxidation and degradation of the polymer melts influence wetting significantly. TiN, TiAlN, CrN, and DLC exhibit a rather good wettability, whereas the highest contact angle of the polymer melts was observed with PTFE. Higher roughnesses of the surfaces lead to an increase in the contact angle. It was also shown that a higher temperature causes a better wetting of the solid surfaces. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43469.
Assessing the incidental value of a marine reserve to a lemon shark Negaprion brevirostris nursery
Authors: Henderson Aaron. C. , Jourdan Adrian , Bell Kathryn
Published: February 2016

The lemon shark is a large coastal species that is currently classified as Near Threatened by the International Union for the Conservation of Nature.

As juveniles of the species utilize shallow, near shore habitat, they are particularly susceptible to anthropogenic impacts.

The abundance, size characteristics, growth, condition factor and movement patterns of juvenile lemon sharks within the Bell Sound Nature Reserve were compared with those outside the Reserve.

Sharks were more abundant within the Reserve, which also accommodated a greater proportion of smaller size classes.

Although there was no difference in linear growth‐rate between sharks inside and outside the Reserve, those outside exhibited higher condition factor values.

It is suggested that these results are due mainly to habitat preference on the part of the sharks, with the predominantly shallower near shore waters of the Reserve offering a greater level of protection from predation.

Regardless of the causative factor, the area occupied by the Bell Sound Nature Reserve appears to be highly important to the local juvenile lemon shark population.

Copyright © 2016 John Wiley & Sons, Ltd.
Factors Determining the Clinical Utility of Serial Measurements of Antineutrophil Cytoplasmic Antibodies Targeting Proteinase 3
Authors: Fussner Lynn A. , Hummel Amber M. , Schroeder Darrell R. , Silva Francisco , Cartin‐Ceba Rodrigo , Snyder Melissa R. , Hoffman Gary S. , Kallenberg Cees G. M. , Langford Carol A. , Merkel Peter A. , Monach Paul A. , Seo Philip , Spiera Robert F. , William St.Clair E. , Tchao Nadia K. , Stone John H. , Specks Ulrich ,   for the Rituximab in ANCA‐Associated Vasculitis–Immune Tolerance Network Research Group
Published: February 2016

Objective

Relapse following remission is common in antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV), particularly with ANCAs directed at proteinase 3 (PR3). This study was undertaken to evaluate the association of an increase in PR3‐ANCA level with subsequent relapse.

Methods

Data from the Rituximab versus Cyclophosphamide for ANCA‐Associated Vasculitis (RAVE) trial were used. Starting from the time of achieving complete remission, serial measurements by direct and capture enzyme‐linked immunosorbent assays (ELISAs) were analyzed in 93 patients with PR3‐ANCA, using Cox proportional hazards regression.

Results

An increase in PR3‐ANCA level was identified in 58 of 93 subjects (62.4%) by direct ELISA and in 59 of 93 (63.4%) by capture ELISA. Relapses occurred in 55 of 93 subjects (59.1%), with 25 and 21 occurring within 1 year after an increase by direct ELISA and capture ELISA, respectively. An increase by direct ELISA was associated with subsequent severe relapses (hazard ratio [HR] 4.57; P < 0.001), particularly in patients presenting with renal involvement (HR 7.94; P < 0.001) and alveolar hemorrhage (HR 24.19; P < 0.001). Both assays identified increased risk for severe relapse in the rituximab group (HR 5.80; P = 0.002 for direct ELISA and HR 4.54; P = 0.007 for capture ELISA) but not the cyclophosphamide/azathioprine group (P = 0.103 and P = 0.197, respectively).

Conclusion

The association of an increase in PR3‐ANCA level with the risk of subsequent relapse is partially affected by the PR3‐ANCA detection methodology, disease phenotype, and remission induction treatment. An increase in PR3‐ANCA level during complete remission conveys an increased risk of relapse, particularly severe relapse, among patients with renal involvement or alveolar hemorrhage and those treated with rituximab. Serial measurements of PR3‐ANCA may be informative in this subset of patients, but the risk of relapse must be weighed carefully against the risks associated with therapy.
Cubic Polyhedral Oligomeric Silsesquioxane Based Functional Materials: Synthesis, Assembly, and Applications
Authors: Ye Qun , Zhou Hui , Xu Jianwei
Published: February 2016

Organically modified cubic polyhedral oligomeric silsesquioxanes (POSS) have attracted increasing attention in the design of novel functional hybrid materials for applications such as porous materials, liquid crystals, semiconductors, high‐temperature lubricants, fuel cells, and lithium batteries. The nanosized POSS moiety can be conveniently modified on the periphery with a variety of functional groups to lead to hybrid materials with desired functions. In addition, suitable mono‐functionalized POSS derivatives can be incorporated into polymers as side chains via various synthetic strategies to offer a wide class of functional polymeric materials with tunable physical properties for targeted applications. In this Focus Review, we aim to summarize the recent developments on the chemistry and applications of POSS‐based molecules and polymers. Moreover, the properties as well as assembly behavior of the POSS‐based functional hybrid materials will be reviewed, and the relationship of the performance of the hybrid materials with the intrinsic nature of the POSS unit will be addressed.
Molecular Design and Syntheses of Tetracyano‐5,10‐porphyrinquinodimethane Showing Stabilized LUMO
Authors: Yamashita Ken‐ichi , Sakamoto Shino , Suzuki Akihiro , Sugiura Ken‐ichi
Published: February 2016

An isomer of tetracyanoporphyrinquinodimethane (TCPQ), 5,10‐TCPQ, was designed, synthesized, and structurally characterized, and its basic properties were discussed with emphasis on comparison with those of reported 5,15‐TCPQ. The title compound was synthesized by a convenient cascade reaction involving a catalyst‐free aromatic nucleophilic substitution reaction and the Uno–Takahashi reaction. The obtained π‐expanded redox molecule acted as a Wurster‐type redox molecule that underwent not only reduction but also oxidation processes. Furthermore, its absorption spectrum showed a large bathochromic shift that extended to the near‐IR region, approximately 1150 nm.
Parametrisierter Brückenentwurf
Authors: Hochmuth Markus
Published: February 2016

Der Planungs‐ und Ausführungsprozess durchläuft mit der Digitalisierung des Bauens einen tiefgreifenden methodischen Wandel. Der Einsatz von BIM (Building Information Modeling) ermöglicht eine durchgängige Planung. Anhand von Projektbeispielen wird erläutert, wie vor allem in den Leistungsphasen der Vor‐, Entwurfs‐ und Ausführungsplanung intelligente parametrisierte Bauwerksmodelle im Brücken‐ und Ingenieurbau erstellt werden können. Die zusätzliche Verknüpfung mit Trassierungs‐ und GIS‐Daten ermöglicht in diesen Phasen eine flexible und belastbare Basis, aufgrund derer man eine ganzheitliche Evaluierung von Planungskonzepten bilden kann. Mit der Anwendung eines parametrisierten, objektorientierten Gesamtmodells kann eine ganzheitliche Prozesskette über den gesamten Planungs‐ und Realisierungszeitraum sowie über den kompletten Lebenszyklus umgesetzt werden. Das 3D‐Modell enthält neben den einzelnen Bauteilen projektspezifische Eigenschaften und Informationen. Mit der Kopplung des digitalen Modells an die Ressourcenplanung, die Kosten und die Termine sowie die Simulation des Bauablaufs entstehen komplexe 4D‐ und 5D‐Brückenmodelle.

Parameterized bridge design – Conceptual, preliminary and detailed design

With the digitalization of construction the planning and implementation process is undergoing a fundamental methodological transformation. The employment of BIM (Building Information Modelling) permits end‐to‐end planning. By means of sample projects it is explained how ‐ above all in the service phases conceptual, preliminary and detailed design ‐ intelligent parameterized building models can be set up in bridge and civil engineering. The additional combination with alignment and GIS data in these phases furnishes a flexible and robust basis upon which to create a holistic evaluation of planning concepts. With the application of a parameterized, object‐oriented complete model it is possible to realize an integral process chain across the whole planning and implementation period as well as across the entire life cycle. The 3D model contains, apart from the individual structural components, project‐specific attributes and information. Coupling the digital model to resource, cost and time scheduling and simulating the construction sequence yield complex 4D and 5D bridge models.
Heterotrimeric G protein signaling via GIV/Girdin: Breaking the rules of engagement, space, and time
Authors: Aznar Nicolas , Kalogriopoulos Nicholas , Midde Krishna K. , Ghosh Pradipta
Published: February 2016

Canonical signal transduction via heterotrimeric G proteins is spatially and temporally restricted, that is, triggered exclusively at the plasma membrane (PM), only by agonist activation of G protein‐coupled receptors (GPCRs) via a process that completes within a few hundred milliseconds. Recently, a rapidly emerging paradigm has revealed a non‐canonical pathway for activation of heterotrimeric G proteins by the non‐receptor guanidine‐nucleotide exchange factor (GEF), GIV/Girdin. This pathway has distinctive temporal and spatial features and an unusual profile of receptor engagement: diverse classes of receptors, not just GPCRs can engage with GIV to trigger such activation. Such activation is spatially and temporally unrestricted, that is, can occur both at the PM and on internal membranes discontinuous with the PM, and can continue for prolonged periods of time. Here, we provide the most complete up‐to‐date review of the molecular mechanisms that govern the unique spatiotemporal aspects of non‐canonical G protein activation by GIV and the relevance of this new paradigm in health and disease.
Intraindividual comparison between open and endoscopic release in bilateral carpal tunnel syndrome: a meta‐analysis of randomized controlled trials
Authors: Hu Kejia , Zhang Tiansong , Xu Wendong
Published: February 2016

Purpose

This study evaluated functional outcomes and safety after endoscopic and open bilateral carpal tunnel syndrome release in opposite hands of the same patients through a meta‐analysis of randomized controlled trial data.

Materials and Methods

Randomized controlled trials involving both methods in opposite hands of patients with bilateral carpal tunnel syndrome were identified via a systematic review of PUBMED and EMBASE.

Results

Relative risks (RRs) and 95% confidence intervals (CIs) from five randomized controlled trials involving 142 patients with bilateral carpal tunnel syndrome were calculated using fixed‐ or random‐effect methods, with a length of follow‐up from 24 to 52 weeks after surgery. Compared with open release, endoscopic carpal tunnel release was associated with significantly better Boston Carpal Tunnel Questionnaire functional status scores (mean difference [MD] = 0.13, 95% confidence interval [CI] [0.02 – 0.25]; P = 0.02), but not symptom severity scores (RR = 0.06, 95% CI [−0.15 to 0.04]; P = 0.25). Endoscopic release required a longer operative time, but the procedures did not differ significantly in visual analog scale pain scores (MD = 0.02, 95% CI [−0.08 to 0.11]; P = 0.75), handgrip strength (MD = 0.17, 95% CI [−2.03 to 2.37]; P = 0.88), digital sensibility static two‐point discrimination (MD = 0.34, 95% CI [−0.03 to 0.70]; P = 0.07), or complication rates (MD = 0.01, 95% CI [−0.02 to 0.05], P = 0.47).

Conclusion

From intraindividual evidence, endoscopic release promoted better recovery of daily life functions than open release, but required a longer operative time. The procedures provided similar symptom relief and hand strength and sensibility recovery, and were safe for patients with carpal tunnel syndrome.
Broadening the spectrum of controls for skin biopsy in painful neuropathies: spondylotic cervical myelopathy patients with painful feet
Authors: Kovalova Ivana , Vlckova Eva , Bednarik Josef
Published: February 2016

Purpose

Intraepidermal nerve fiber density (IENFD) is useful in the evaluation of small‐fiber neuropathy (SFN). Recent guidelines recommend extending the spectrum of controls for IENFD assessment by evaluation of patients whose clinical picture mimics that of SFN. The aim of this study was to broaden the spectrum of IENFD controls by the assessment of patients with cervical spondylotic myelopathy (CSM) and painful feet.

Methods

Evaluation of IENFD from skin biopsy samples and quantitative sensory testing (QST) were performed in a cohort of 14 CSM patients (eight men, median age: 58; range: 46–63 years), with painful feet, exhibiting no clinical or electrophysiological signs of large‐fiber polyneuropathy, and no risk factors for peripheral neuropathies.

Results

Quantitative sensory testing abnormalities were found in all but two of the CSM patients (86%), while the IENFD values were within reference range. The mean IENFD value (6.87 ± 2.78 fibers/mm) did not differ from that of an age‐ and sex‐matched cohort of healthy volunteers (7.97 ± 2.21 fibers/mm, P > 0.05).

Conclusions

The study confirmed normal skin biopsy findings in patients with CSM as one of the clinical conditions mimicking SFN and provided further support for the use of IENFD assessment in case of suspicion of SFN.
Glycosylation status of serum immunoglobulin G in patients with prostate diseases
Authors: Kazuno Saiko , Furukawa Jun‐ichi, , Shinohara Yasuro , Murayama Kimie , Fujime Makoto , Ueno Takashi , Fujimura Tsutomu
Published: February 2016

Occurrences of high values in patients with benign prostate disease and low values in patients with highly suspicious cancer have diminished the trustworthiness of prostate‐specific antigen as an early diagnostic marker of prostate cancer. In the search for other complimentary markers, we focused on serum IgG from patients with prostate diseases as well as normal subjects. IgG purified from the sera of normal control subjects and patients with prostate diseases, was digested with peptide N‐glycanase. Released glycans were quantified using MALDI‐time of flight mass spectrometry. We report that N‐linked (N‐acetylhexosamine)2(deoxyhexose)(mannose)3(N‐acetylglucosamine)2 was significantly increased in the IgG heavy chains of patients with prostate cancer compared with that of either benign prostatic disease patients or healthy subjects, whereas (hexose)(N‐acetylhexosamine)2(deoxyhexose)(mannose)3 (N‐acetylglucosamine)2 was more abundant in the heavy chains of healthy subjects and benign prostatic disease patients. Thus, an absence of the terminal hexose of N‐linked glycans has been closely connected to the progression of prostate cancer. Furthermore, surface plasmon resonance analyses have revealed that IgG from patients with prostate cancer has a decreased binding for Sambucus nigra lectin, compared with that from the benign prostatic disease patients or from normal subjects, suggesting lower levels of (N‐acetylneuraminic acid)(α2‐6)galactose/N‐acetylgalactosamine groups in the N‐linked glycans of patient IgG. Meanwhile, wheat germ agglutinin binding to IgG of the cancer group was significantly larger than that for the benign prostatic disease group but smaller than that for normal subjects. Our study indicates that the glycosylation changes in IgG can become useful diagnostic parameters for prostate cancer.
Essential‐Oil Constituents and Alkanes of Cephalaria ambrosioidesRoem. & Schult. (Family Caprifoliaceae, Subfamily Dipsacaceae) and (Chemo)taxonomic Discernment of the Subfamilies Dipsacaceae and Morinaceae
Authors: Vukićević Dušan R. , Stevanović Dragana D. , Genčić Marija S. , Blagojević Polina D. , Radulović Niko S.
Published: February 2016

Herein, the results of the first study of the volatile and alkane profiles of Cephalaria ambrosioides Roem. & Schult. (Caprifoliaceae, subfamily Dipsacaceae) were reported. The GC‐FID and GC/MS analyses of the essential oils hydrodistilled from leaves and stems (CA1) and flowers (CA2) of C. ambrosioides allowed the identification of 284 different components. The main compounds of the studied oil samples were palmitic acid (24.3 and 32.5% for CA1 and CA2, resp.), hexahydrofarnesyl acetone (1.4 and 10.8% for CA1 and CA2, resp.), (Z)‐hex‐3‐en‐1‐ol (7.0 and <0.1% for CA1 and CA2, resp.), and linoleic acid (1.9 and 6.5% for CA1 and CA2, resp.). Essential‐oil compositional data of selected plant species belonging to the Dipsacaceae (15) and Morinaceae (2) subfamilies were used to resolve taxonomical ambiguities regarding the genus Cephalaria and its infrageneric relations, especially concerning the subfamily Morinaceae (formerly a genus within Dipsacaceae). The results of multivariate statistical analyses (25 different essential‐oil samples) supported the exclusion of Morina species from the Dipsacaceae subfamily. The relative abundances of alkanes from n‐, iso‐, and anteiso‐series followed a (distorted) Gaussian‐like distribution and suggested that the biosyntheses of n‐ and branched alkanes in C. ambrosioides are possibly not controlled by the same elongase. Also, the obtained results suggested that there was a difference in the biosynthesis/accumulation of alkanes in the vegetative and reproductive parts of C. ambrosioides.
Contribution to a Taxonomic Revision of the Sicilian Helichrysum Taxa by PCA Analysis of Their Essential‐Oil Compositions
Authors: Maggio Antonella , Bruno Maurizio , Guarino Riccardo , Senatore Felice , Ilardi Vincenzo
Published: February 2016

The chemical profile of the essential oils in ten populations of the genus Helichrysum Mill. (Asteraceae), collected in the loci classici of the nomenclatural types of the taxa endemic to Sicily, were analyzed. Our results confirm that the analysis of secondary metabolites can be used to fingerprint wild populations of Helichrysum, the chemical profiles being coherent with the systematic arrangement of the investigated populations in three main clusters, referring to the aggregates of H. stoechas, H. rupestre, and H. italicum, all belonging to the section Stoechadina. The correct nomenclatural designation of the investigated populations is discussed and the following two new combinations are proposed: Helichrysum preslianum subsp. compactum (Guss.) Maggio, Bruno, Guarino, Senatore & Ilardi and Helichrysum panormitanum subsp. latifolium Maggio, Bruno, Guarino, Senatore & Ilardi.
Comprehensive Study of Mediterranean (Croatian) Propolis Peculiarity: Headspace, Volatiles, Anti‐Varroa‐Treatment Residue, Phenolics, and Antioxidant Properties
Authors: Jerković Igor , Marijanović Zvonimir , Kuś Piotr M. , Tuberoso Carlo I. G.
Published: February 2016

Eight propolis samples from Croatia were analyzed in detail, to study the headspace, volatiles, anti‐Varroa‐treatment residue, phenolics, and antioxidant properties. The samples exhibited high qualitative/quantitative variability of the chemical profiles, total phenolic content (1,589.3–14,398.3 mg GAE (gallic acid equivalent)/l EtOH extract), and antioxidant activity (11.1–133.5 mmol Fe2+/l extract and 6.2–65.3 mmol TEAC (Trolox® equivalent antioxidant capacity)/l extract). The main phenolics quantified by HPLC‐DAD at 280 and 360 nm were vanillin, p‐coumaric acid, ferulic acid, chrysin, galangin, and caffeic acid phenethyl ester. The major compounds identified by headspace solid‐phase microextraction (HS‐SPME), simultaneous distillation extraction (SDE), and subsequent GC‐FID and GC/MS analyses were α‐eudesmol (up to 19.9%), β‐eudesmol (up to 12.6%), γ‐eudesmol (up to 10.5%), benzyl benzoate (up to 28.5%), and 4‐vinyl‐2‐methoxyphenol (up to 18.1%). Vanillin was determined as minor constituent by SDE/GC‐FID/MS and HPLC‐DAD. The identified acaricide residue thymol was ca. three times more abundant by HS‐SPME/GC‐FID/MS than by SDE/GC‐FID/MS and was not detected by HPLC‐DAD.
‘Does my Diet Affect my Perfume?’ Identification and Quantification of Cuticular Compounds in Five Drosophila melanogaster Strains Maintained over 300 Generations on Different Diets
Authors: Pavković‐Lučić Sofija , Todosijević Marina , Savić Tatjana , Vajs Vlatka , Trajković Jelena , Anđelković Boban , Lučić Luka , Krstić Gordana , Makarov Slobodan , Tomić Vladimir , Miličić Dragana , Vujisić Ljubodrag
Published: February 2016

Cuticular hydrocarbons (CHCs) in Drosophila melanogaster represent the basis of chemical communication being involved in many important biological functions. The aim of this study was to characterize chemical composition and variation of cuticular profiles in five D. melanogaster strains. These strains were reared for approximately 300 generations on five diets: standard cornmeal medium and substrates prepared with apple, banana, tomato, and carrot. Differences in quantity and/or quality in CHCs were assumed as a result of activation of different metabolic pathways involved in food digestion and adaptations to the particular diet type.

In total, independently of sex and strain, 66 chemical compounds were identified. In females of all strains, 60 compounds were identified, while, in males, 47 compounds were extracted. Certain new chemical compounds for D. melanogaster were found. MANOVA confirmed that CHC amounts significantly depend on sex and substrates, as well as on their interactions. Discriminant analysis revealed that flies belonging to ‘apple’ and ‘carrot’ strains exhibited the most noticeable differences in CHC repertoires. A non‐hydrocarbon pheromone, cis‐vaccenyl acetate (cVA) also contributed to the variation in the pheromone bouquet among the strains. Variability detected in CHCs and cVA may be used in the explanation of differences in mating behaviour previously determined in analyzed fly strains.
Novel Nucleolipids of Pyrimidine β‐D‐Ribonucleosides: Combinatorial Synthesis, Spectroscopic Characterization, and Cytostatic/Cytotoxic Activities
Authors: Knies Christine , Hammerbacher Katharina , Bonaterra Gabriel A. , Kinscherf Ralf , Rosemeyer Helmut
Published: February 2016

Four series of nucleolipids with either uridine, 5‐methyluridine, 5‐fluorouridine, and 6‐azauridine as β‐D‐ribonucleoside component have been prepared in a combinatorial (not parallel!) manner (see Formulae). All compounds have been characterized by elemental analyses, ESI mass spectrometry as well as by 1H‐, and 13C‐NMR, and UV spectroscopy. A selection of eight nucleolipids with different lipophilizing moieties, based on earlier findings, as well as of 5‐fluorouridine as control were first tested on their cytotoxic effect towards PMA‐differentiated human THP‐1 macrophages. Those compounds which did not exhibit a significant inhibitory effect on the survival of the macrophages were next tested on their cytostatic/cytotoxic effect towards the human astrocytoma/oligodendroglioma GOS‐3 cells as well as against the rat malignant neuroectodermal BT4Ca cell line. Additionally, induction of apoptosis of the cell lines was evaluated. It turned out that particularly a combined lipophilization of the nucleosides by an 2′,3′‐O‐ethyl levulinate residue plus a farnesyl moiety at N(3) of the pyrimidine moiety of the corresponding nucleolipids leads to an active compound with the highest probability.
Activated Alumina Balls under Neat Conditions: A Green Catalyst for the Synthesis of Spiro‐Heterocyclic Scaffolds by Ring‐Opening versus Annulation of the Isatin Moiety
Authors: Mondal Animesh , Banerjee Biplab , Bhaumik Asim , Mukhopadhyay Chhanda
Published: February 2016

We report a green, efficient and straightforward approach for the regioselective synthesis of new spiro‐heterocyclic scaffolds using environmentally benevolent activated alumina balls (3–5 mm diameter) as a catalyst under neat reaction conditions. The methodology is advantageous because of its short reaction time, moderate to excellent yields, easy work‐up, practical simplicity and high regioselectivity without any troublesome/hazardous disposal of the catalyst or toxic byproducts. The pore size of the catalyst plays a key role in the formation of the spiro derivatives. Specifically, we observed that the reaction yield was hardly affected by the surface area or pore volume, but surprisingly, the yield correlated directly with the pore size of the catalyst.
Simple Continuous High‐Pressure Hydrogen Production and Separation System from Formic Acid under Mild Temperatures
Authors: Iguchi Masayuki , Himeda Yuichiro , Manaka Yuichi , Matsuoka Koichi , Kawanami Hajime
Published: February 2016

The front cover artwork for Issue 05/2016 is provided by Prof. Dr. Hajime Kawanami and colleagues. The image shows the continuous high‐pressure gas evolution system over 120 MPa without any compressing procedure followed by a vapor–liquid H2 separation. See the Communication itself at https://doi.org/10.1002/cctc.201501296.
Ion‐Pair SN2 Substitution: Activation Strain Analyses of Counter‐Ion and Solvent Effects
Authors: Laloo Jalal Z. A. , Rhyman Lydia , Ramasami Ponnadurai , Bickelhaupt F. Matthias , de Cózar Abel
Published: February 2016

The ion‐pair SN2 reactions of model systems MnFn−1+CH3Cl (M+=Li+, Na+, K+, and MgCl+; n=0, 1) have been quantum chemically explored by using DFT at the OLYP/6‐31++G(d,p) level. The purpose of this study is threefold: 1) to elucidate how the counterion M+ modifies ion‐pair SN2 reactivity relative to the parent reaction F−+CH3Cl; 2) to determine how this influences stereochemical competition between the backside and frontside attacks; and 3) to examine the effect of solvation on these ion‐pair SN2 pathways. Trends in reactivity are analyzed and explained by using the activation strain model (ASM) of chemical reactivity. The ASM has been extended to treat reactivity in solution. These findings contribute to a more rational design of tailor‐made substitution reactions.
Abnormal Cathodic Photocurrent Generated on an n‐Type FeOOH Nanorod‐Array Photoelectrode
Authors: Chen Hongjun , Lyu Miaoqiang , Liu Gang , Wang Lianzhou
Published: February 2016

A simple, wet‐chemical method for the synthesis of an FeOOH nanorod‐array photoelectrode on fluorine‐doped tin oxide (FTO) glass is reported. Nanorods of diameter about 35 nm and length about 300 nm have been vertically grown on an FTO substrate. Upon calcination, the FeOOH phase could be easily converted to a hematite structure while maintaining the shape of the nanorod array. An interesting abnormal cathodic photocurrent is generated on the FeOOH nanorod‐array photoelectrode under illumination, which is totally different from that obtained on a calcined hematite photoelectrode under the same experimental conditions. The cathodic photocurrent density generated on the FeOOH photoelectrode can also be tuned by applying an electrochemical anodic or cathodic treatment. Detailed analysis has revealed that higher valence state FeIV species in the FeOOH photoelectrode play an important role in sacrificing the photoexcited electrons for generation of the cathodic photocurrent. Comparison between the FeOOH and hematite photoelectrodes allows for a better understanding of the interplay between crystal structure, surface reactions, and photocurrent. The findings on this new abnormal phenomenon could also provide guidance for the design of new types of semiconducting photoelectrochemical devices.
Nitration of Norcorrolatonickel(II): First Observation of a Diatropic Current in a System Comprising a Norcorrole Ring
Authors: Deng Zhihong , Li Xiaofang , Stępień Marcin , Chmielewski Piotr J.
Published: February 2016

A one‐pot reaction of 5,14‐bis(mesityl)‐norcorrolatonickel(II) with isoamyl nitrite under mild reaction conditions resulted in the consecutive formation of 3‐nitro‐, 3,12‐dinitro‐ and 3,16‐dinitro‐, 3,7,12‐trinitro‐, and 3,7,12,16‐tetranitro‐norcorrolatonickel(II) in 50–80 % yield. The substituted macrocycles retained their antiaromatic character. The observed regioselectivity of the substitution was analyzed by comparing the relative energies of the DFT energy‐optimized models of the radical or arenium cationic intermediates that can be formed upon reaction with NO2. The nitrated systems were characterized by high‐resolution mass spectrometry, NMR and UV/Vis spectroscopy, X‐ray diffraction analysis, cyclic voltammetry, and DFT calculations. A significant and systematic cathodic shift of the redox couples was observed to correlate with an increasing number of the NO2 group. A decrease of the LUMO energies in the tri‐ and tetra‐nitrated products stabilizes mono‐ and bis‐reduced complexes of these ligands. The reduction takes place on the macrocycle rather than on the metal ion leading to the consecutive formation of stable paramagnetic monoanion radicals and water‐soluble diamagnetic dianions with an aromatic character, which were revealed by ESR and 1H NMR measurements, respectively. The electronic structures of the reduced forms were analyzed by extensive TD‐DFT calculations.
Biodegradable Peptide–Silica Nanodonuts
Authors: Maggini Laura , Travaglini Leana , Cabrera Ingrid , Castro‐Hartmann Pablo , De Cola Luisa
Published: February 2016

We report hybrid organosilica toroidal particles containing a short peptide sequence as the organic component of the hybrid systems. Once internalised in cancer cells, the presence of the peptide allows for interaction with peptidase enzymes, which attack the nanocarrier effectively triggering its structural breakdown. Moreover, these biodegradable nanovectors are characterised by high cellular uptake and exocytosis, showing great potential as biodegradable drug carriers. To demonstrate this feature, doxorubicin was employed and its delivery in HeLa cells investigated.
Control of Surface Plasmon Resonance of Au/SnO2 by Modification with Ag and Cu for Photoinduced Reactions under Visible‐Light Irradiation over a Wide Range
Authors: Tanaka Atsuhiro , Hashimoto Keiji , Kominami Hiroshi
Published: February 2016

Gold particles supported on tin(IV) oxide (0.2 wt % Au/SnO2) were modified with copper and silver by the multistep photodeposition method. Absorption around λ=550 nm, attributed to surface plasmon resonance (SPR) of Au, gradually shifted to longer wavelengths on modification with Cu and finally reached λ=620 nm at 0.8 wt % Cu. On the other hand, the absorption shifted to shorter wavelength with increasing amount of Ag and reached λ=450 nm at 0.8 wt % Ag. These Cu‐ and Ag‐modified 0.2 wt % Au/SnO2 materials (Cu‐Au/SnO2 and Ag‐Au/SnO2) and 1.0 wt % Au/SnO2 were used for mineralization of formic acid to carbon dioxide in aqueous suspension under irradiation with visible light from a xenon lamp and three kinds of light‐emitting diodes with different wavelengths. The reaction rates for the mineralization of formic acid over these materials depend on the wavelength of light. Apparent quantum efficiencies of Cu‐Au/SnO2, Au/SnO2, and Ag‐Au/SnO2 reached 5.5 % at 625 nm, 5.8 % at 525 nm, and 5.1 % at 450 nm, respectively. These photocatalysts can also be used for selective oxidation of alcohols to corresponding carbonyl compounds in aqueous solution under visible‐light irradiation. Broad responses to visible light in formic acid mineralization and selective alcohol oxidation were achieved when the three materials were used simultaneously.
Controllable Synthesis of Mesoporous Iron Oxide Nanoparticle Assemblies for Chemoselective Catalytic Reduction of Nitroarenes
Authors: Papadas Ioannis T. , Fountoulaki Stella , Lykakis Ioannis N. , Armatas Gerasimos S.
Published: February 2016

Iron(III) oxide is a low‐cost material with applications ranging from electronics to magnetism, and catalysis. Recent efforts have targeted new nanostructured forms of Fe2O3 with high surface area‐to‐volume ratio and large pore volume. Herein, the synthesis of 3D mesoporous networks consisting of 4–5 nm γ‐Fe2O3 nanoparticles by a polymer‐assisted aggregating self‐assembly method is reported. Iron oxide assemblies obtained from the hybrid networks after heat treatment have an open‐pore structure with high surface area (up to 167 m2 g−1) and uniform pores (ca. 6.3 nm). The constituent iron oxide nanocrystals can undergo controllable phase transition from γ‐Fe2O3 to α‐Fe2O3 and to Fe3O4 under different annealing conditions while maintaining the 3D structure and open porosity. These new ensemble structures exhibit high catalytic activity and stability for the selective reduction of aryl and alkyl nitro compounds to the corresponding aryl amines and oximes, even in large‐scale synthesis.
Reversible Morphological Evolution of Responsive Giant Vesicles to Nanospheres by the Self‐Assembly of Crystalline‐b‐Coil Polyphosphazene Block Copolymers
Authors: Suárez‐Suárez Silvia , Carriedo Gabino A. , Presa Soto Alejandro
Published: February 2016

The preparation of long‐term‐stable giant unilamellar vesicles (GUVs, diameter ≥1000 nm) and large vesicles (diameter ≥500 nm) by self‐assembly in THF of the crystalline‐b‐coil polyphosphazene block copolymers [N=P(OCH2CF3)2]n‐b‐[N=PMePh]m (4 a: n=30, m=20; 4 b: n=90, m=20; 4 c: n=200, m=85), which combine crystalline [N=P(OCH2CF3)2] and amorphous [N=PMePh] blocks, both of which are flexible, is reported. SEM, TEM, and wide‐angle X‐ray scattering experiments demonstrated that the stability of these GUVs is induced by crystallization of the [N=P(OCH2CF3)2] blocks at the capsule wall of the GUVS, with the [N=PMePh] blocks at the corona. Higher degrees of crystallinity of the capsule wall are found in the bigger vesicles, which suggests that the crystallinity of the [N=P(OCH2CF3)2] block facilitates the formation of large vesicles. The GUVs are responsive to strong acids (HOTf) and, after selective protonation of the [N=PMePh] block, they undergo a morphological evolution to smaller spherical micelles in which the core and corona roles have been inverted. This morphological evolution is totally reversible by neutralization with a base (NEt3), which regenerates the original GUVs. The monitoring of this process by dynamic light scattering allowed a mechanism to to be proposed for this reversible morphological evolution in which the block copolymer 4 a and its protonated form 4 a+ are intermediates. This opens a route to the design of reversibly responsive polymeric systems in organic solvents. This is the first reversibly responsive vesicle system to operate in organic media.
Heteroleptic Tetrapyrrole‐Fused Dimeric and Trimeric Skeletons with Unusual Non‐Frustrated Fluorescence
Authors: Zhang Yuehong , Oh Juwon , Wang Kang , Chen Chao , Cao Wei , Park Kyu Hyung , Kim Dongho , Jiang Jianzhuang
Published: February 2016

Phthalocyanine (Pc) and porphyrin (Por) chromophores have been fused through the benzo[α]pyrazine moiety, resulting in unprecedented heteroleptic tetrapyrrole‐fused dimers and trimers. The heteroleptic tetrapyrrole nature has been clearly revealed based on single‐crystal X‐ray diffraction analysis of the zinc dimer. Electrochemical analysis, theoretical calculations, and time‐resolved spectroscopic results disclose that the two/three‐tetrapyrrole‐fused skeletons behave as one totally π‐conjugated system as a result of the strong conjugative interaction between/among the tetrapyrrole chromophores. In particular, the effectively extended π‐electron system through the fused‐bridge induced strong electronic communication between the Pc and Por moieties and large transition dipole moments in the Pc–Por‐fused systems, providing high fluorescence quantum yields (>0.13) and relatively long excited state lifetimes (>1.3 ns) in comparison with their homo‐tetrapyrrole‐fused analogues.
Structural Collapse of the Hydroquinone–Formic Acid Clathrate: A Pressure‐Medium‐Dependent Phase Transition
Authors: Eikeland Espen , Thomsen Maja K. , Madsen Solveig R. , Overgaard Jacob , Spackman Mark A. , Iversen Bo. B.
Published: February 2016

The energy landscape governing a new pressure‐induced phase transition in the hydroquinone–formic acid clathrate is reported in which the host structure collapses, opening up the cavity channels within which the guest molecules migrate and order. The reversible isosymmetric phase transition causes significant changes in the morphology and the birefringence of the crystal. The subtle intermolecular interaction energies in the clathrate are quantified at varying pressures using novel model energies and energy frameworks. These calculations show that the high‐pressure phase forms a more stable host network at the expense of less‐stable host–guest interactions. The phase transition can be kinetically hindered using a nonhydrostatic pressure‐transmitting medium, enabling the comparison of intermolecular energies in two polymorphic structures in the same pressure range. Overall this study illustrates a need for accurate intermolecular energies when analyzing self‐assembly structures and supramolecular aggregates.
Selectivity Effects in Bimetallic Catalysis
Authors: Mankad Neal P.
Published: February 2016

An emerging area of homogeneous catalysis is the use of catalysts featuring two closely associated metal sites. This approach complements the traditional focus on single‐site catalysts and makes available new parameters with which to optimize catalytic behavior. Single‐site catalysts are optimized through changing 1) the identity of the metal, and 2) the steric and electronic properties of the ligands. Bimetallic catalysts introduce new optimization parameters such as 3) catalyst nuclearity (mononuclear vs. binuclear), and 4) bimetallic pairing (relative compatibility of two metal sites). In order to harness these new optimization parameters in developing systems, it is necessary to first understand the origin of bimetallic selectivity effects that already have been documented. This Concept article highlights bimetallic effects on the chemo‐, regio‐, and stereoselectivity of catalytic transformations, using selected case studies from the recent literature as illustrative examples.
The Quadruple Bonding in C2 Reproduces the Properties of the Molecule
Authors: Shaik Sason , Danovich David , Braida Benoit , Hiberty Philippe C.
Published: February 2016

Ever since Lewis depicted the triple bond for acetylene, triple bonding has been considered as the highest limit of multiple bonding for main elements. Here we show that C2 is bonded by a quadruple bond that can be distinctly characterized by valence‐bond (VB) calculations. We demonstrate that the quadruply‐bonded structure determines the key observables of the molecule, and accounts by itself for about 90 % of the molecule's bond dissociation energy, and for its bond lengths and its force constant. The quadruply‐bonded structure is made of two strong π bonds, one strong σ bond and a weaker fourth σ‐type bond, the bond strength of which is estimated as 17–21 kcal mol−1. Alternative VB structures with double bonds; either two π bonds or one π bond and one σ bond lie at 129.5 and 106.1 kcal mol−1, respectively, above the quadruply‐bonded structure, and they collapse to the latter structure given freedom to improve their double bonding by dative σ bonding. The usefulness of the quadruply‐bonded model is underscored by “predicting” the properties of the 3
state. C2’s very high reactivity is rooted in its fourth weak bond. Thus, carbon and first‐row main elements are open to quadruple bonding!
Mit der Eberesche vom Heimatlied zur Frühstücksmagarine
Authors: Selg Christoph , Geißler David , Sicker Dieter , Siehl Hans‐Ullrich , Zeller Klaus‐Peter , Berger Stefan
Published: February 2016

Die Eberesche gehört zu den anpassungsfähigen Bäumen der Pioniervegetation. Vogelbeeren sind die Früchte der Eberesche. Sie sind essbar, aber es ist nötig zu wissen, wie sie zuzubereiten sind, damit ihr Verzehr ein Genuss wird. Auch volksmedizinische Anwendungen sind bekannt. Der Vogelbeerbaum wird so geschätzt, dass es sogar ein Volkslied über ihn gibt. Typisch sind die Inhaltsstoffe Parasorbosid (1), ein Glucosid, und Parasorbinsäure (2), ein Lacton und Sorbinsäure (3), eine isomere ungesättigte Carbonsäure. Diese ist ein Konservierungsstoff, welcher sich chemisch aus 2 herstellen lässt. In über 100 Jahren ermittelten z.T. berühmte Chemiker diese Strukturen. Wir beschreiben den Zugang zu 1, 2 und 3 auf Vogelbeerenbasis. Alle analytischen Spektren werden vollständig entweder im Hauptteil oder in der supporting information wiedergegeben und interpretiert.