bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Porous Palladium(II)‐polyimine in Cooperatively‐ catalyzed Highly Enantioselective Cascade Transformations
Authors: Xu Chao , Deiana Luca , Afewerki Samson , Incerti‐Pradillos Celia , Córdova Oscar , Guo Peng , Córdova Armando , Hedin Niklas 
Published: April 2015

AbstractPorous organic polymers have prospects as functional substrates for catalysis, with quite different molecular properties from inorganic substrates. Here we disclose for the first time that porous palladium(II)‐polyimines are excellent catalysts for cooperatively catalyzed and enantioselective cascade reactions. In synergy with a chiral amine co‐catalyst, polysubstituted cyclopentenes and spirocyclic oxindoles, including the all‐carbon quaternary stereocenter, were synthesized in high yields. High diastereo‐ and enantioselectivities were achieved for these dynamic kinetic asymmetric transformations (DYKAT) of enals with propargylic nucleophiles.magnified image
Chronic lymphocytic leukemia: 2015 Update on diagnosis, risk stratification, and treatment
Authors: Hallek Michael 
Published: April 2015

Disease overview: Chronic lymphocytic leukemia (CLL) is the commonest leukemia in western countries. The disease typically occurs in elderly patients and has a highly variable clinical course. Leukemic transformation is initiated by specific genomic alterations that impair apoptosis of clonal B‐cells.Diagnosis: The diagnosis is established by blood counts, blood smears, and immunophenotyping of circulating B‐lymphocytes, which identify a clonal B‐cell population carrying the CD5 antigen as well as B‐cell markers.Prognosis: Two prognostic staging systems exist, the Rai and Binet staging systems, which are established by physical examination and blood counts. Various biological and genetic markers also have prognostic value. Deletions of the short arm of chromosome 17 (del(17p)) predict resistance to available chemotherapies. Comprehensive prognostic scores are currently being developed.Therapy: Patients with active or symptomatic disease or with advanced Binet or Rai stages require therapy. For physical fit patients, chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab remains the current standard therapy. For unfit patients, treatment with an anti‐CD20 antibody (obinutuzumab or rituximab or ofatumumab) plus a milder chemotherapy (Chlorambucil) may be applied. At relapse, the initial treatment may be repeated, if the treatment‐free interval exceeds two to three years. If the disease relapses earlier, therapy should be changed using alternative agents such as bendamustine (plus rituximab), alemtuzumab, lenalidomide, ofatumumab, ibrutinib, or idelalisib. Patients with a del(17p) or TP53 mutation can be treated with ibrutinib or a combination of idelalisib and rituximab. An allogeneic SCT may be considered in relapsing patients with TP53 mutations or del(17p) or patients that are refractory to repeated chemoimmunotherapies.Future challenges: Several new agents (e.g., ibrutinib, idelalisib, obinutuzumab) hold the potential to improve the outcome of patients with CLL. However, their optimal use (in terms of combination, sequence, and duration) is unknown. Therefore, CLL patients should be treated in clinical trials whenever possible.Am. J. Hematol. 90:447–460, 2015. © 2015 Wiley Periodicals, Inc.
Catalytic Enantioselective Synthesis of N,Cα,Cα‐Trisubstituted α‐Amino Acid Derivatives Using 1H‐Imidazol‐4(5H)‐ones as Key Templates
Authors: Etxabe Julen , Izquierdo Joseba , Landa Aitor , Oiarbide Mikel , Palomo Claudio 
Published: April 2015

Abstract1H‐Imidazol‐4(5H)‐ones are introduced as novel nucleophilic α‐amino acid equivalents in asymmetric synthesis. These compounds not only allow highly efficient construction of tetrasubstituted stereogenic centers, but unlike hitherto known templates, provide direct access to N‐substituted (alkyl, allyl, aryl) α‐amino acid derivatives.
Radical Covalent Organic Frameworks: A General Strategy to Immobilize Open‐Accessible Polyradicals for High‐Performance Capacitive Energy Storage
Authors: Xu Fei , Xu Hong , Chen Xiong , Wu Dingcai , Wu Yang , Liu Hao , Gu Cheng , Fu Ruowen , Jiang Donglin 
Published: April 2015

AbstractOrdered π‐columns and open nanochannels found in covalent organic frameworks (COFs) could render them able to store electric energy. However, the synthetic difficulty in achieving redox‐active skeletons has thus far restricted their potential for energy storage. A general strategy is presented for converting a conventional COF into an outstanding platform for energy storage through post‐synthetic functionalization with organic radicals. The radical frameworks with openly accessible polyradicals immobilized on the pore walls undergo rapid and reversible redox reactions, leading to capacitive energy storage with high capacitance, high‐rate kinetics, and robust cycle stability. The results suggest that channel‐wall functional engineering with redox‐active species will be a facile and versatile strategy to explore COFs for energy storage.
Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene
Authors: Ogoshi Tomoki , Yoshikoshi Kumiko , Sueto Ryuta , Nishihara Hirotomo , Yamagishi Tada‐aki 
Published: April 2015

AbstractWe report a new synthesis method of fibrous carbon material with pores sizes that are precisely controlled at the Ångstrom level, by carbonization of two dimensional (2D) porous sheets of pillar[6]arenes. The 2D porous sheets were prepared by 2D supramolecular polymerization induced by oxidation of hydroquinone units of pillar[6]arenes. Owing to the hexagonal structure of pillar[6]arene, the assembly induced by 2D supramolecular polymerization gave hexagonal 2D porous sheets, and the highly ordered structure of the 2D porous sheets formed regular fibrous structures. Then, carbonization of the 2D porous sheets afforded fibrous carbon materials with micropores. The micropore size of the fibrous porous carbon prepared from pillar[6]arene was the same size as that of the starting material pillar[6]arene assembly.
Chemoselective Silylative Reduction of Conjugated Nitriles under Metal‐Free Catalytic Conditions: β‐Silyl Amines and Enamines
Authors: Gandhamsetty Narasimhulu , Park Juhyeon , Jeong Jinseong , Park Sung‐Woo , Park Sehoon , Chang Sukbok 
Published: April 2015

AbstractThe B(C6F5)3‐catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable β‐silyl amines. The reaction is chemoselective and proceeds under mild conditions. Mechanistic elucidation indicates that it proceeds by rapid double hydrosilylation of the conjugated nitrile to an enamine intermediate which is subsequently reduced to the β‐silyl amine, thus forming a new C(sp3)Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes.
Elusive Silane–Alane Complex [SiH⋅⋅⋅Al]: Isolation, Characterization, and Multifaceted Frustrated Lewis Pair Type Catalysis
Authors: Chen Jiawei , Chen Eugene Y.‐X. 
Published: April 2015

AbstractThe super acidity of the unsolvated Al(C6F5)3 enabled isolation of the elusive silane–alane complex [SiH⋅⋅⋅Al], which was structurally characterized by spectroscopic and X‐ray diffraction methods. The Janus‐like nature of this adduct, coupled with strong silane activation, effects multifaceted frustrated‐Lewis‐pair‐type catalysis. When compared with the silane–borane system, the silane–alane system offers unique features or clear advantages in the four types of catalytic transformations examined in this study, including: ligand redistribution of tertiary silanes into secondary and quaternary silanes, polymerization of conjugated polar alkenes, hydrosilylation of unactivated alkenes, and hydrodefluorination of fluoroalkanes.
Organocatalyzed CO2 Trapping Using Alkynyl Indoles
Authors: Xin Zhuo , Lescot Camille , Friis Stig D. , Daasbjerg Kim , Skrydstrup Troels 
Published: April 2015

AbstractThe first organocatalyzed trapping of CO2 through CC and CO bond formation is reported. Alkynyl indoles together with catalytic amounts of an organic base and five equivalents of CO2 resulted in the formation new heterocyclic structures. These tricyclic indole‐containing products were successfully prepared under mild reaction conditions from aromatic, heteroaromatic, and aliphatic alkynyl indoles with complete regioselectivity. Further investigations suggest that CC bond formation is the initial intermolecular step, followed by lactone‐forming CO bond formation.
Neuritogenic Militarinone‐Inspired 4‐Hydroxypyridones Target the Stress Pathway Kinase MAP4K4
Authors: Schröder Peter , Förster Tim , Kleine Stefan , Becker Christian , Richters André , Ziegler Slava , Rauh Daniel , Kumar Kamal , Waldmann Herbert 
Published: April 2015

AbstractProgressive loss and impaired restoration of neuronal activity are hallmarks of neurological diseases, and new small molecules with neurotrophic activity are in high demand. The militarinone alkaloids and structurally simplified analogues with 4‐hydroxy‐2‐pyridone core structure induce pronounced neurite outgrowth, but their protein target has not been identified. Reported herein is the synthesis of a militarinone‐inspired 4‐hydroxy‐2‐pyridone collection, its investigation for enhancement of neurite outgrowth, and the discovery of the stress pathway kinase MAP4K4 as a target of the discovered neuritogenic pyridones. The most potent 4‐hydroxy‐2‐pyridone is a selective ATP‐competitive inhibitor of MAP4K4 but not of the other stress pathway related kinases, as proven by biochemical analysis and by a crystal structure of the inhibitor in complex with MAP4K4. The findings support the notion that MAP4K4 may be a new target for the treatment of neurodegenerative diseases.
One‐Step Synthesis of [16]Helicene
Authors: Mori Kazuyuki , Murase Takashi , Fujita Makoto 
Published: April 2015

AbstractA single‐strand arylene–vinylene precursor containing four phenylene and three naphthylene units linked together with six vinylene spacers undergoes helical folding via sextuple photocyclization to give a [16]helicene core in a single step. The phenylene and naphthylene units are arranged in the precursor such that unfavorable side reactions (anthracene or benzoperylene formation) are avoided, and this is the key to the success of the one‐step synthesis of [16]helicene, which is the longest [n]helicene that has been synthesized to date.
Rhodium‐Catalyzed Enantioselective Intramolecular CH Silylation for the Syntheses of Planar‐Chiral Metallocene Siloles
Authors: Zhang Qing‐Wei , An Kun , Liu Li‐Chuan , Yue Yuan , He Wei 
Published: April 2015

AbstractReported herein is the rhodium‐catalyzed enantioselective CH bond silylation of the cyclopentadiene rings in Fe and Ru metallocenes. Thus, in the presence of (S)‐TMS‐Segphos, the reactions took place under very mild conditions to afford metallocene‐fused siloles in good to excellent yields and with ee values of up to 97 %. During this study it was observed that the steric hindrance of chiral ligands had a profound influence on the reactivity and enantioselectivity of the reaction, and might hold the key to accomplishing conventionally challenging asymmetric CH silylations.
Selected Gray Matter Volumes and Gender but Not Basal Ganglia nor Cerebellum Gyri Discriminate Left Versus Right Cerebral Hemispheres: Multivariate Analyses in human Brains at 3T
Authors: Roldan‐Valadez Ernesto , Suarez‐May Marcela A. , Favila Rafael , Aguilar‐Castañeda Erika , Rios Camilo 
Published: April 2015

ABSTRACTInterest in the lateralization of the human brain is evident through a multidisciplinary number of scientific studies. Understanding volumetric brain asymmetries allows the distinction between normal development stages and behavior, as well as brain diseases. We aimed to evaluate volumetric asymmetries in order to select the best gyri able to classify right‐ versus left cerebral hemispheres. A cross‐sectional study performed in 47 right‐handed young‐adults healthy volunteers. SPM‐based software performed brain segmentation, automatic labeling and volumetric analyses for 54 regions involving the cerebral lobes, basal ganglia and cerebellum from each cerebral hemisphere. Multivariate discriminant analysis (DA) allowed the assembling of a predictive model. DA revealed one discriminant function that significantly differentiated left vs. right cerebral hemispheres: Wilks’ λ = 0.008, χ2 (9) = 238.837, P < 0.001. The model explained 99.20% of the variation in the grouping variable and depicted an overall predictive accuracy of 98.8%. With the influence of gender; the selected gyri able to discriminate between hemispheres were middle orbital frontal gyrus (g.), angular g., supramarginal g., middle cingulum g., inferior orbital frontal g., calcarine g., inferior parietal lobule and the pars triangularis inferior frontal g. Specific brain gyri are able to accurately classify left vs. right cerebral hemispheres by using a multivariate approach; the selected regions correspond to key brain areas involved in attention, internal thought, vision and language; our findings favored the concept that lateralization has been evolutionary favored by mental processes increasing cognitive efficiency and brain capacity. Anat Rec, 298:1336–1346, 2015. © 2015 Wiley Periodicals, Inc.
Multiple Model Adaptive Estimator for Nonlinear System with Unknown Disturbance
Authors: Xiong Kai , Wei Chunling 
Published: April 2015

AbstractA multiple model adaptive estimator (MMAE) is presented for nonlinear systems with unknown disturbances. Multiple models are constructed with a set of process noise covariance matrices, such that the algorithm can adapt to different levels of unknown disturbances. The performance of the MMAE is analyzed for the considered system. It is proved that, under certain assumptions, the MMAE keeps the dynamics of its estimation error stable. A performance comparison among different estimators is carried out for space surveillance, where the position of a space target is estimated by using double line‐of‐sight measurements. Simulation studies illustrate that the presented algorithm outperforms the extended Kalman filter and the nonlinear robust filter.
Challenges and advances in the assessment of the disposition of antibody‐drug conjugates
Authors: Kamath Amrita V. , Iyer Suhasini 
Published: April 2015

AbstractAntibody‐drug conjugates (ADCs) are a rapidly growing therapeutic platform for the treatment of cancer. ADCs consist of a cytotoxic small molecule drug linked to an antibody to provide targeted delivery of the cytotoxic agent to the tumor. Understanding the pharmacokinetics (PK) and pharmacodynamics (PD) of ADCs is crucial in their design to optimize dose and regimen, to maximize efficacy and to minimize toxicity in patients. Significant progress has been made in recent years in this area, however, many fundamental questions still remain. This review discusses factors to consider while assessing the disposition of ADCs, and the unique challenges associated with these therapeutics. Current tools that are available and strategies to enable appropriate assessment are also discussed. © 2015 Genentech Inc. Biopharmaceutics & Drug Disposition Published by John Wiley & Sons Ltd.
Unbalanced chemical equations conversion to mark‐up format and representation to vision impaired students
Authors: Nazemi Azadeh , McMeekin David A. , Murray Iain 
Published: April 2015

ABSTRACTThis paper describes a method to represent unbalanced chemical equations to vision impaired students which allows them to navigate through classified data, such as species, elements, quantity numbers at the left and right hand sides of equations, reactants, and products. Then they can find appropriate coefficients and balance chemical equations without involving to mathematical aspects of balancing and remembering a lot of information. The goal of this research was the development of an application which assists vision impaired students enrolled in chemistry course to be able to read chemistry literature containing formulae, chemistry representations of elements, and other aspects of chemistry that has been difficult in the past to present in a way for vision impaired people to understand. Developed application by this research is an open source command line Bash Script application under Linux which accepts an unbalanced chemical equation as an input, processes, classifies information, and represents it as Mark‐up format or Alternative Audio Descriptive using Text to Speech. © 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:805–812, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21651
Single‐fraction radiation therapy in patients with metastatic Merkel cell carcinoma
Authors: Iyer Jayasri G. , Parvathaneni Upendra , Gooley Ted , Miller Natalie J. , Markowitz Elan , Blom Astrid , Lewis Christopher W. , Doumani Ryan F. , Parvathaneni Kaushik , Anderson Austin , Bestick Amy , Liao Jay , Kane Gabrielle , Bhatia Shailender , Paulson Kelly , Nghiem Paul 
Published: April 2015

AbstractMerkel cell carcinoma (MCC) is an aggressive, polyomavirus‐associated cancer with limited therapeutic options for metastatic disease. Cytotoxic chemotherapy is associated with high response rates, but responses are seldom durable and toxicity is considerable. Here, we report our experience with palliative single‐fraction radiotherapy (SFRT) in patients with metastatic MCC. We conducted retrospective analyses of safety and efficacy outcomes in patients that received SFRT (8 Gy) to MCC metastases between 2010 and 2013. Twenty‐six patients were treated with SFRT to 93 MCC tumors located in diverse sites that included skin, lymph nodes, and visceral organs. Objective responses were observed in 94% of the measurable irradiated tumors (86/92). Complete responses were observed in 45% of tumors (including bulky tumors up to 16 cm). “In field” lesion control was durable with no progression in 77% (69/89) of treated tumors during median follow‐up of 277 days among 16 living patients. Clinically significant toxicity was seen in only two patients who had transient side effects. An exploratory analysis suggested a higher rate of in‐field progression in patients with an immunosuppressive comorbidity or prior recent chemotherapy versus those without (30% and 9%, respectively; P = 0.03). Use of SFRT in palliating MCC patients was associated with an excellent in field control rate and durable responses at treated sites, and with minimal toxicity. SFRT may represent a convenient and appealing alternative to systemic chemotherapy for palliation, for which most patients with oligometastatic MCC are eligible. SFRT may also synergize with emerging systemic immune stimulants by lowering tumor burden and enhancing presentation of viral/tumor antigens.
Exploring Bacterial Heparinase II Activities with Defined Substrates
Authors: Bohlmann Lisa , Chang Chih‐Wei , Beacham Ifor , von Itzstein Mark 
Published: April 2015

AbstractBacterial heparinases that cleave heparan sulfate (HS) and heparin are widely used to generate low‐molecular‐weight heparins (LMWHs) and to structurally and functionally characterise heparin and HS biomolecules. We provide novel insights into the substrate specificity of heparinase II from two different bacteria: Pedobacter heparinus (formerly Flavobacterium heparinum) and Bacteroides eggerthii. The activity towards various well‐defined HS oligosaccharides was investigated by 1H NMR spectroscopy; this revealed distinct specificities for the two heparinases. Heparinase II from P. heparinus appears to be more active and displays a broader substrate specificity than B. eggerthii heparinase II. Furthermore, HS di‐ and tetrasaccharides inhibited B. eggerthii heparinase II activity. A better understanding of heparinase substrate specificity will contribute to the production of homogenous LMWHs, provide better characterisation of heparin and HS and assist therapeutic applications.
Obesity and percutaneous coronary intervention outcomes: Beware the extremes
Authors: Hillegass William B. , Brott Brigitta C. 
Published: April 2015

Key Points

Observational associations between high body mass index (BMI) and putatively improved outcomes after percutaneous coronary intervention (PCI) have been called the “obesity paradox.”
The present study shows no association between two year PCI outcomes and BMI ranging from 23 to 34 kg/m2.
Under‐represented in this study, the BMI extremes of <23 and >40 kg/m2 are associated with worse outcomes in the broader literature; but require further study including lean body mass index.
Association of embolism and stroke in the catheterization laboratory
Authors: Gilchrist Ian C. 
Published: April 2015

Key Points

Strokes continue to be a rare but potentially devastating event during cardiac catheterization
Most strokes are associated with brain imaging patterns consistent with embolic etiologies
Common embolic etiology supports not only the critical importance of catheterization laboratory techniques to minimize activation of thrombosis or embolism, but also point to potential treatment with rapid application of neurovascular brain salvage techniques.
Optimizing endovascular stroke therapy: A primary PCI deja‐vu?
Authors: Cilingiroglu Mehmet , Marmagkiolis Kostas 
Published: April 2015

Key Points

The optimal revascularization modality (thromboembolectomy, suction thrombectomy, angioplasty with stenting, and stent retriever thrombectomy) for the cerebral circulation remains to be defined
Catheter‐based therapy of the acute stroke yields better clinical outcomes in patients <65‐year‐old, with a door‐to‐balloon time <4 hr and successful reperfusion TICI ≥ 2.
Considering the significant incidence of acute strokes which are either ineligible for intravenous thrombolytic therapy or present too late, catheter‐based therapies may offer an alternative treatment option.
Interventional cardiologists should play an active role in the development of endovascular stroke therapy in a multi‐disciplinary team approach.
Palladium‐Catalyzed Construction of Heteroatom‐Containing π‐Conjugated Systems by Intramolecular Oxidative CH/CH Coupling Reaction
Authors: Saito Kenta , Chikkade Prasanna Kumara , Kanai Motomu , Kuninobu Yoichiro 
Published: April 2015

AbstractSynthesis of heteroatom‐containing ladder‐type π‐conjugated molecules was successfully achieved via a palladium‐catalyzed intramolecular oxidative CH/CH cross‐coupling reaction. This reaction provides a variety of π‐conjugated molecules bearing heteroatoms, such as nitrogen, oxygen, phosphorus, and sulfur atoms, and a carbonyl group. The π‐conjugated molecules were synthesized efficiently, even in gram scale, and larger π‐conjugated molecules were also obtained by a double CH/CH cross‐coupling reaction and successive oxidative cycloaromatization.
ChemInform Abstract: Pr3S2Cl2[AsS3]: A Praseodymium(III) Sulfide Chloride Thioarsenate(III) with Double Chains of Condensed [SPr4]10+ Tetrahedra.
Authors: Kang Dong‐Hee , Ledderboge Florian , Kleinke Holger , Schleid Thomas 
Published: April 2015

AbstractSingle crystals of Pr3S2Cl2[AsS3] are obtained by solid state reaction of Pr2S3, PrCl3, As, and S in a molar ratio of 7:4:6:9 (evacuated silica tubes, 850 °C, 7 d) followed by slow cooling (50 °C/d) to room temperature.
ChemInform Abstract: Triangular Ge3 Units in a New Modification of EuGe3.
Authors: Castillo Rodrigo , Baranov Alexey I. , Burkhardt Ulrich , Grin Yuri , Schwarz Ulrich 
Published: April 2015

AbstractThe hexagonal modification hP8 of EuGe3 is obtained by arc‐melting of a stoichiometric mixture of the elements (1% excess of Eu) followed by high‐pressure sintering (multianvil press, 12 GPa, 1100 K, 1 h).
ChemInform Abstract: A Series of Noncentrosymmetric Antimony Sulfides Ln8Sb2S15 (Ln: La, Pr, Nd) — Syntheses, Crystal and Electronic Structures, and NLO Properties.
Authors: Zhao Hua‐Jun , Zhou Liu‐Jiang 
Published: April 2015

AbstractLn8Sb2S15 (Ln: La, Pr, Nd) are prepared by heating stoichiometric mixtures of the elements (evacuated silica tubes, 950 °C, 4 d; cooling to 200 °C at a rate of 2.5 °C/h).