bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lucifensin, a Novel Insect Defensin of Medicinal Maggots: Synthesis and Structural Study
Authors: Čeřovský Václav , Slaninová Jiřina , Fučík Vladimír , Monincová Lenka , Bednárová Lucie , Maloň Petr , Štokrová Jitka 
Published: May 2011

AbstractRecently, we identified a new insect defensin, named lucifensin that is secreted/excreted by the blowfly Lucilia sericata larvae into a wound as a disinfectant during the medicinal process known as maggot therapy. Here, we report the total chemical synthesis of this peptide of 40 amino acid residues and three intramolecular disulfide bridges by using three different protocols. Oxidative folding of linear peptide yielded a peptide with a pattern of disulfide bridges identical to that of native lucifensin. The synthetic lucifensin was active against Gram‐positive bacteria and was not hemolytic. We synthesized three lucifensin analogues that are cyclized through one native disulfide bridge in different positions and having the remaining four cysteines substituted by alanine. Only the analogue cyclized through a Cys16–Cys36 disulfide bridge showed weak antimicrobial activity. Truncating lucifensin at the N‐terminal by ten amino acid residues resulted in a drop in antimicrobial activity. Linear lucifensin having all six cysteine residues alkylated was inactive. Circular dichroism spectra measured in the presence of α‐helix‐promoting compounds showed different patterns for lucifensin and its analogues. Transmission electron microscopy revealed that Bacillus subtilis treatment with lucifensin induced significant changes in its envelope.
Manipulating the Expression Rate and Enantioselectivity of an Epoxide Hydrolase by Using Directed Evolution
Authors: Reetz Manfred T. , Zheng Huabao 
Published: May 2011

AbstractWe describe here a strategy to improve the expression efficiency and enantioselectivity of Aspergillus niger epoxide hydrolase (ANEH) by directed evolution. Based on a blue‐colony screening system using the LacZα (β‐galactosidase α peptide) complementation solubility reporter, several ANEH variants out of 15 000 transformants from a random‐mutagenesis library were identified that show improved recombinant expression in E. coli. Among them, Pro221Ser was subsequently used as a template for iterative saturation mutagenesis (ISM) at sites around the ANEH binding pocket. Following four rounds of ISM, a highly enantioselective mutant was identified that catalyzes the hydrolytic kinetic resolution of racemic glycidyl phenyl ether with a selectivity factor of E=160 in favor of the (S)‐diol compared to WT ANEH characterized by E=4.6. Expression of this mutant is 50 times higher than that of WT ANEH. It also serves as an excellent stereoselective catalyst in the hydrolytic kinetic resolution and desymmetrization of several other structurally diverse epoxides.
Interfacial Impregnation Chemistry in the Synthesis of Chromium Catalysts Supported on Titania
Authors: Petsi Theano , Panagiotou George D. , Bourikas Kyriakos , Kordulis Christos , Voyiatzis George A. , Lycourghiotis Alexis 
Published: May 2011

AbstractThe interfacial impregnation chemistry involved in the synthesis of CrVI catalysts supported on titania is presented. The mode of interfacial deposition of the CrVI oxo‐species at the titania/electrolyte solution interface, the interfacial species, and the local structure of the deposited species were investigated. Several methodologies based on potentiometric titrations, microelectrophoresis, and adsorption experiments were used. Modeling of the interfacial deposition based on experimental results provided an integrated picture concerning the deposition features. The interfacial species were confirmed by using laser Raman spectroscopy. The deposited CrO42−, HCrO4−, and Cr2O72− ions are retained above the positively charged bridging hydroxyl groups (Ti2OH) of the titania surface as electrostatic forces cause the formation of ion‐pairs. Each CrO42− or HCrO4− ion is located above a bridging hydroxyl, and each Cr2O72− ion above two bridging hydroxyl groups. Only the CrO42− and HCrO4− ions are deposited, with a preference for the CrO42− ions, at low CrVI surface concentrations (up to 0.3 μmol CrVI m−2). Cr2O72− ions were deposited in addition to CrO42− and HCrO4− ions at higher CrVI concentrations. The direct probing of the interfacial species by using laser Raman spectroscopy confirmed the interfacial species determined by modeling the deposition data. The deposition model developed describes all of the experimental data (from adsorption, titration, and microelectrophoresis experiments) very well. Moreover, it accurately predicts the displacements of pzc and iep caused by the presence of these species in the solution.
Reaction Mechanism of Aerobic Oxidation of Alcohols Conducted on Activated‐Carbon‐Supported Cobalt Oxide Catalysts
Authors: Zhu Junjiang , Faria Joaquim L. , Figueiredo José L. , Thomas Arne 
Published: May 2011

AbstractCatalytic performances and the reaction mechanism of Co3O4/AC (AC=activated carbon) for aerobic oxidation of alcohols carried out in the liquid phase were investigated. Co3O4/AC shows a high activity for aerobic oxidation of benzyl alcohol, comparable to noble metal catalysts (e.g., Au/AC) even in the absence of additives or promoters (e.g., NaOH). Changing preparation conditions, such as treatment temperature and/or time, can affect the catalytic performances of Co3O4/AC, due to decomposition of surface groups of the carbon support. Careful studies show that low alcohol conversions are obtained with either Co3O4 or AC alone, which indicates that the high conversion observed over the Co3O4/AC is due to a synergistic effect between Co3O4 and AC. Parallel experiments using a high‐surface‐area covalent triazine framework or oxygen‐inert carbon nitride as support for the Co3O4 catalyst also show lower conversions, which suggest that the ability of AC (in Co3O4/AC) to activate molecular oxygen is essential for the reaction. FTIR and XPS spectra taken from catalysts before and after the reaction confirm that oxygen activation proceeds mainly on the carbon support. As a result, it can be assumed that the alcohol dehydrogenation step proceeds on the metal oxide, whereas the oxygen activation step occurs mainly on the carbon support.
Palladium‐Catalyzed Cycloisomerizations of Diarylacetylenes: Synthesis, Structures, and Physical Properties of Highly Substituted Naphthalenes and 8,8 a‐Dihydrocyclopenta[a]indenes
Authors: Wu Tsun‐Cheng , Tai Chia‐Cheng , Tiao Hsin‐Chieh , Chang Yu‐Ting , Liu Chia‐Chun , Li Ching‐Hsiu , Huang Cheng‐Hao , Kuo Ming‐Yu , Wu Yao‐Ting 
Published: May 2011

AbstractDepending on the electronic properties of their substituents, the major products generated by palladium‐catalyzed cycloisomerizations of diarylalkynes are either highly substituted 8,8a‐dihydrocyclopenta[a]indenes 3 or naphthalenes 4. The structures of these compounds were verified by X‐ray crystallographic analysis. Many functional groups tolerated the reaction conditions evaluated in this study. The isotope‐labeled experiments indicated that added water has a critical role in forming both classes of compounds. The photophysical and electrochemical properties of cycloadducts 3 and their analogues were systematically studied and compared with computational predictions based on density functional theory. Dihydrocyclopenta[a]indenes 3 in either solid or liquid form display strong luminescence, whereas cyclopenta[a]indene 11 j is practically nonfluorescent. The functional groups directly attached to the backbone of compound 3 significantly influenced physical properties. The steric effect arising from the aryl substituents caused different luminescence phenomena, including aggregation‐induced and ‐enhanced emission.
Structural Investigation and Biological Activity of the Lipooligosaccharide from the Psychrophilic Bacterium Pseudoalteromonas haloplanktis TAB 23
Authors: Carillo Sara , Pieretti Giuseppina , Parrilli Ermenegilda , Tutino Maria L. , Gemma Sabrina , Molteni Monica , Lanzetta Rosa , Parrilli Michelangelo , Corsaro Maria M. 
Published: May 2011

AbstractPseudoalteromonas haloplanktis TAB 23 is a Gram‐negative psychrophilic bacterium isolated from the Antarctic coastal sea. To survive in these conditions psychrophilic bacteria have evolved typical membrane lipids and “antifreeze” proteins to protect the inner side of the microorganism. As for Gram‐negative bacteria, the outer membrane is mainly constituted by lipopoly‐ or lipooligosaccharides (LPS or LOS, respectively), which lean towards the external environment. Despite this, very little is known about the peculiarity of LPS from Gram‐negative psychrophilic bacteria and what their role is in adaptation to cold temperature. Here we report the complete structure of the LOS from P. haloplanktis TAB 23. The lipid A was characterized by MALDI‐TOF MS analysis and was tested in vitro showing a significant inhibitory effect on the LPS‐induced pro‐inflammatory cytokine production when added in culture with LPS from Escherichia coli. The product obtained after de‐O‐acylation of the LPS was analyzed by MALDI‐TOF MS revealing the presence of several molecular species, differing in phosphorylation degree and oligosaccharide length. The oligosaccharide portion released after strong alkaline hydrolysis was purified by anion‐exchange chromatography–pulsed amperometric detection (HPAEC‐PAD) to give three main fractions, characterized by means of 2D NMR spectroscopy, which showed a very short highly phosphorylated saccharidic chain with the following general structure. α‐Hepp3R,6R,4R′‐(1→5)‐α‐Kdop4P‐(2→6)‐β‐GlcpN4R‐(1→6)‐α‐GlcpN1P (R=H2PO3 or H; R′=α‐Galp‐(1→4)‐β‐Galp‐(1→ or H).
ChemInform Abstract: A Comparison of the Transport Properties of Lithium‐Stuffed Garnets and the Conventional Phases Li3Ln3Te2O12.
Authors: Cussen Edmund J. , Yip Thomas W. S. , O'Neill Gemma , O'Callaghan Michael P. 
Published: May 2011

AbstractThe structures of the new lithium‐stuffed garnets Li6CaLa2Sb2O12 and Li6.4Ca1.4La1.6Sb2O12 are determined by neutron powder diffraction.
ChemInform Abstract: Synthesis, Structural and Electrical Characterization of Sb3+ Substituted Spinel Nickel Ferrite (NiSbxFe2‐xO4) Nanoparticles by Reverse Micelle Technique.
Authors: Ashiq Muhamamd Naeem , Ehsan Muhammad Fahad , Iqbal Muhammad Javed , Gul Iftikhar Hussain 
Published: May 2011

AbstractTitle compounds with 0 ≤ x ≤ 1 are synthesized by the reverse microemulsion method using Ni(NO3)2, Fe(NO3)3, and SbCl3 as precursors, iso‐octane as oil phase, cetyltrimethylammoniumbromid as surfactant, an BuOH as cosurfactant.
ChemInform Abstract: Chemical Synthesis, Structural and Magnetic Properties of Nano‐Structured Co—Zn—Fe—Cr Ferrite.
Authors: Alone S. T. , Shirsath Sagar E. , Kadam R. H. , Jadhav K. M. 
Published: May 2011

AbstractNanoparticles of Co1‐xZnxFe2‐xCrxO4 (x = 0.0—0.5) are prepared by co‐precipitation from aqueous solutions of the metal sulfates, followed by annealing at 600 °C for 12 h.
ChemInform Abstract: Synthesis and Photoactivity of the Highly Efficient Ag Species/TiO2 Nanoflakes Photocatalysts.
Authors: Liu Yong , Hu Juncheng , Li Jinlin 
Published: May 2011

AbstractThe title catalysts are prepared from suspensions of TiO2 nanoflakes in EtOH solutions of AgNO3 (3 h in the dark), followed by illumination with a 300 W high pressure mercury lamp for 3 h, and calcination at 500 °C for 3 h and 8 h in air.
ChemInform Abstract: LiB12PC, the First Boron‐Rich Metal Boride with Phosphorus — Synthesis, Crystal Structure, Hardness, Spectroscopic Investigations.
Authors: Vojteer Natascha , Sagawe Vanessa , Stauffer Julia , Schroeder Melanie , Hillebrecht Harald 
Published: May 2011

AbstractTransparent single crystals of the title compound are prepared from the elements in a Ga/Li melt (BN crucibles welded in Ta ampules, 1500 °C, 60 h).
ChemInform Abstract: Solvothermal Syntheses, Crystal Structures, and Thermal Properties of the First Example of Selenidostannates with Mixed Ethylene Polyamine‐Coordinated Transition Metal Complexes as Counterions.
Authors: Liang Jingjing , Chen Jiangfang , Zhao Jing , Pan Yingli , Zhang Yong , Jia Dingxian 
Published: May 2011

AbstractCompounds (IVa,b) crystallize in the monoclinic space group P21/n with Z = 2, and compounds (V) and (VI) in the orthorhombic space group Pbca with Z = 4.
ChemInform Abstract: A New Oxapalladacycle Generated via ortho C—H Activation of Phenylphosphinic Acid: An Efficient Catalyst for Markovnikov‐Type Additions of E—H Bonds to Alkynes.
Authors: Xu Qing , Shen Ruwei , Ono Yutaka , Nagahata Ritsuko , Shimada Shigeru , Goto Midori , Han Li‐Biao 
Published: May 2011

AbstractComplexes derived from the new, stable oxapalladacycle OPC are found to be more efficient and selective catalysts for addition reactions of H‐heteroatom compounds to alkynes than the common Pd‐complexes used so far.
ChemInform Abstract: Organocatalyst‐Mediated Aldol—Robinson Cascade Reactions: A Convenient Synthesis of Substituted Cyclohex‐2‐enones.
Authors: Wang Li , Gong Qing‐Ping , Liu Xiao‐Jun , Li Yong‐Hong , Huang Ping , Wang Bi‐Qin , Zhao Ke‐Qing 
Published: May 2011

AbstractAn efficient, enamine‐mediated aldol‐Robinson cascade reaction of aldehydes with acetone gives cyclohexenone derivatives (III) (14 examples) in moderate to high yields under mild reaction conditions.
ChemInform Abstract: Asymmetric Synthesis of Amines by the Knochel‐Type MgCl2‐Enhanced Addition of Benzyl Zinc Reagents to N‐tert‐Butanesulfinyl Aldimines.
Authors: Buesking Andrew W. , Baguley Tyler D. , Ellman Jonathan A. 
Published: May 2011

AbstractThe reaction proceeds easily at room temperature and tolerates a wide range of aromatic imines and benzyl zinc reagents.
ChemInform Abstract: Mild Conversion of Esters Lacking Acidic α‐Hydrogens into Amides via Samarium(III) Tris[hexamethyldisilazide] and Amines.
Authors: Campbell James B. , Sparks Richard B. , Dedinas Robert F. 
Published: May 2011

AbstractLanthanum and samarium tris(hexamethyldisilazide) efficiently promote the reactions of aromatic esters with amines.
ChemInform Abstract: Chiral Phosphine Squaramides as Enantioselective Catalysts for the Intramolecular Morita—Baylis—Hillman Reaction.
Authors: Song Hong‐Liang , Yuan Kui , Wu Xin‐Yan 
Published: May 2011

AbstractNovel squaramides (I) containing a tertiary phosphine are developed and tested in the title reaction of ω‐formyl‐enone (II).
ChemInform Abstract: Synthesis of Pyrenes by Twofold Hydroarylation of 2,6‐Dialkynylbiphenyls.
Authors: Matsuda Takanori , Moriya Taisaku , Goya Tsuyoshi , Murakami Masahiro 
Published: May 2011

AbstractCationic gold(I) complexes having a Buchwald‐type biarylphosphine ligand effectively catalyze twofold hydroarylation of 2,6‐dialkylbiphenyls to provide access to corresponding pyrene skeletons.
ChemInform Abstract: Synthesis of Tetrahydrofurans by Cyclization of Homoallylic Alcohols with Iodine/Iodine(III).
Authors: Vasconcelos Ramon S. , Silva Luiz F. Jr. , Giannis Athanassios 
Published: May 2011

AbstractIt provides a new, simple, and metal‐free approach to tetrahydrofurans.
ChemInform Abstract: Organocatalytic Direct Asymmetric Vinylogous Michael Reaction of an α,β‐Unsaturated γ‐Butyrolactam with Enones.
Authors: Zhang Yong , Shao Yong‐Liang , Xu Hai‐Sen , Wang Wei 
Published: May 2011

AbstractThe title reaction allows an efficient and highly stereoselective access to substituted lactams of type (III).
ChemInform Abstract: Reductive Alkylation of Indoles with Alkynes and Hydrosilanes under Indium Catalysis.
Authors: Tsuchimoto Teruhisa , Kanbara Mitsutaka 
Published: May 2011

AbstractA variety of indole derivatives is alkylated at the 3‐position with terminal and internal alkynes and hydrosilane as hydrogen nucleophile.
ChemInform Abstract: CuBr‐Catalyzed Coupling of N‐Tosylhydrazones and Terminal Alkynes: Synthesis of Benzofurans and Indoles.
Authors: Zhou Lei , Shi Yi , Xiao Qing , Liu Yizhou , Ye Fei , Zhang Yan , Wang Jianbo 
Published: May 2011

AbstractThe reaction of ortho‐hydroxy ortho‐aminobenzaldehydes with terminal alkynes leads to the formation of the title heterocycles.
ChemInform Abstract: Synthesis of 2‐Keto‐imidazoles Utilizing N‐Arylamino‐Substituted N‐Heterocyclic Carbenes.
Authors: Zarganes‐Tzitzikas Tryfon , Neochoritis Constantinos G. , Stephanidou‐Stephanatou Julia , Tsoleridis Constantinos A. 
Published: May 2011

AbstractThe products are of synthetic and biological interest.
ChemInform Abstract: One‐Pot Synthesis of 4,5‐Disubstituted 1,2,3‐(NH)‐Triazoles Using Terminal Acetylenes, Carbon Monoxide, Aryl Iodides, and Sodium Azide.
Authors: Li Na , Wang Dong , Li Jihui , Shi Weilin , Li Chao , Chen Baohua 
Published: May 2011

AbstractThe alkynes, CO and the aryl iodides undergo Pd‐catalyzed carbonylative Sonogashira reaction to yield an alkynone intermediate which is directly coupled with azide to give the title triazoles.
ChemInform Abstract: Selective Synthesis of 3,4‐Dihydrocoumarins and Chalcones from Substituted Aryl Cinnamic Esters.
Authors: Jeon Jae‐Ho , Yang Deok‐Mo , Jun Jong‐Gab 
Published: May 2011

AbstractNew selective methods for the synthesis of dihydrocoumarins and chalcones from cinnamates are developed using acid catalyzed intramolecular cyclization or a Fries‐rearrangement, respectively.
ChemInform Abstract: Heteroaromatic Synthesis via Olefin Cross‐Metathesis: Entry to Polysubstituted Pyridines.
Authors: Donohoe Timothy J. , Basutto Jose A. , Bower John F. , Rathi Akshat 
Published: May 2011

AbstractThe straightforward and efficient method to prepare mono‐, di‐, tri‐, and tetrasubstituted pyridines can be applied to the synthesis of macrocyclic pyridines such as (+)‐muscopyridine (XV).
ChemInform Abstract: Synthesis of New Benzo[c]phenanthridine Derivatives.
Authors: Pyrko A. N. 
Published: May 2011

AbstractThree component condensation of naphthylamine (I) with triethyl orthoformate and dimedone or reaction of amine (I) with 2‐acetylcyclohexanedione deivatives (VI) affords corresponding enamino diketones (IV) and (VIII), resp., which undergo PPA‐mediated intramolecular cyclizations to furnish new benzophenanthridine derivatives in good yields.
ChemInform Abstract: Dihydro‐3H‐chromeno[3,4‐b][4,7]phenanthrolin‐3‐one and Chromeno[4,3‐b]pyrano[3,2‐f]quinolin‐3(13H)‐one Derivatives by Aza‐Diels—Alder Reaction.
Authors: Majumdar K. C. , Ponra Sudipta , Taher Abu 
Published: May 2011

AbstractA novel, convenient, practical and efficient protocol for the synthesis of the title compounds (III) is described by using a commercially available catalyst.
ChemInform Abstract: 3‐(Dichloroacetyl)chromone; a New Building Block for the Synthesis of Formylated Purine Isosteres: Design and Synthesis of Fused α‐(Formyl)pyridines.
Authors: Iaroshenko Viktor O. , et al. et al. 
Published: May 2011

AbstractThe reaction of 1,1‐dichloro‐4‐ethoxybut‐3‐en‐2‐one (II) or the novel title compound (XV) with a variety of electron‐rich amino‐heterocycles gives a range of diversely fused pyridines bearing a CHCl2‐substituent.
ChemInform Abstract: A Divergent Synthesis of Dihydropyridazinones, N‐Substituted Dihydropyrazoles, and O‐Substituted Pyrazoles.
Authors: Masumoto Eiichi , Maruoka Hiroshi , Okabe Fumi , Nishida Sho , Yoshimura Yuki , Fujioka Toshihiro , Yamagata Kenji 
Published: May 2011

AbstractReaction of spirocyclopropanepyrazole derivative (I) with α‐chloro esters (III) in the presence of a NaI/K2CO3 system results in cyclopropane ring opening and subsequent C‐ or N‐substitution to furnish dihydropyridazines (IV) and N‐substituted dihydropyrazoles (V).
ChemInform Abstract: A Simple and Convenient Approach to the Synthesis of Aminofuropyrimidinediones.
Authors: Shaabani Ahamd , Teimouri Mohammad Bagher , Afgheh Mohammad , Eskandari Mehrdad 
Published: May 2011

AbstractA facile and efficient route to the title furopyrimidinediones (17 examples), compounds of potential synthetic and biological interest, is given using one‐pot three‐component reactions of dimethylbarbituric acid with aromatic aldehydes and isocyanides.
ChemInform Abstract: A New Antifungal Yellow Pigment from Aspergillus nishimurae
Authors: Hosoe Tomoo , Mori Nobuaki , Kamano Kumi , Itabashi Takeshi , Yaguchi Takeshi , Kawai Ken‐ichi 
Published: May 2011

Abstractstructure elucidation, antifungal and cytotoxic activities of the new pigment, anishidiol (I)
ChemInform Abstract: Two New Sesquiterpenes from Inula salsoloides and Their Inhibitory Activities Against NO Production.
Authors: Hu Xiao‐Jia , Jin Hui‐Zi , Liu Xiao‐Hua , Zhang Wei‐Dong 
Published: May 2011

Abstractisolation and structure elucidation of inulasalene (I) and inulasalsolide B (II)
ChemInform Abstract: A Novel Sesquiterpenoid Glucoside from Hedyosmum orientale
Authors: Rao Gui‐Wei , Zhan Zha‐Jun , Li Cheng‐Ping , Shan Wei‐Guang 
Published: May 2011

Abstractisolation of the novel sesquiterpenoid, hedyosmum F (I) along with three known sesquiterpenoids
ChemInform Abstract: Synthetic Studies of Lepranthin, a Lichen‐Produced Dimeric Macrolide. Stereoselective Synthesis of a seco‐Acid Based on Stereospecific Epoxide‐Opening Reactions.
Authors: Takada Hisashi , Nagumo Shinji , Yasui Eiko , Mizukami Megumi , Miyashita Masaaki 
Published: May 2011

AbstractSeco‐acid derivative (I), the key monomer segment of lepranthin, is synthesized.
ChemInform Abstract: Synthesis and Antibacterial Activities of Pleuromutilin Derivatives with Quinazolinone and Thioether Groups.
Authors: Yao Yuan‐peng , Dai Fu‐ying , Dong Kui‐kui , Mao Qiang , Wang Yu‐liang , Chen Tian 
Published: May 2011

AbstractTen novel pleuromutilin derivatives (V) are synthesized, which all exhibit higher antibacterial activity against S.
Ultrafiltration for Acute Decompensated Heart Failure: Cost, Reimbursement, and Financial Impact
Authors: Ross Edward A. , Bellamy Frank B. , Hawig Scott , Kazory Amir 
Published: May 2011

AbstractIn addition to the proposed pathophysiologic mechanisms whereby ultrafiltration (UF) can be advantageous over diuretics in the treatment of heart failure, there can also be financial and resource‐utilization reasons for pursuing this extracorporeal strategy. In those cases in which the clinical outcomes would be equivalent, however, the decision whether to pursue UF will depend greatly on the anticipated hospitalization length of stay (LOS), the patient population's payor mix, the needs and costs for high‐acuity (eg, intensive care unit) care, and widely varying expenses for the equipment and disposable supplies. From a fiscal perspective, the financial viability of UF programs revolves around how improvements in LOS, resource utilization, and readmissions relate to the typical diagnosis‐driven (eg, diagnosis‐related group) reimbursement. We analyzed the impact of these various factors so as to better understand how the intensity (and expense) of pharmaceutical and extracorporeal therapies impacts a single admission, as well as to serve as the basis for developing strategies for optimizing long‐term care. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.