bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual Hard/Soft Gold Catalysis: Intermolecular Friedel–Crafts‐Type α‐Amidoalkylation/Alkyne Hydroarylation Sequences by N‐Acyliminium Ion Chemistry
Authors: Boiaryna Liliana , El Mkaddem Mohamed Kamal , Taillier Catherine , Dalla Vincent , Othman Mohamed 
Published: September 2012

AbstractGold catalysts have been applied in cascade‐type reactions for the synthesis of different nitrogen‐based compounds. The reactions likely proceed by a new gold‐catalyzed cascade intermolecular α‐amidoalkylation/intramolecular carbocyclization cascade process by unifying both the σ‐ and π‐Lewis acid properties of the gold salts. In the first part of this report we show that the σ‐Lewis acidity of gold(I) and gold(III) could be exploited to efficiently catalyze the nucleophilic substitution of various alkoxy‐ and acetoxylactams. The reaction was found to be applicable to a wide range of cyclic N‐acyliminium ion precursors and various nucleophiles, including allyltrimethylsilane, silyl enol ethers, arenes, and active methylene derivatives. As a logical progression of this study, a combined hard/soft binary catalytic gold system was then used to implement an unprecedented tandem intermolecular Friedel–Crafts amidoalkylation/intramolecular hydroarylation sequence allowing an expedient access to new, complex, fused polyheterocyclic structures from trivial materials.
Synthesis of 11‐cis‐Retinoids by Hydrosilylation–Protodesilylation of an 11,12‐Didehydro Precursor: Easy Access to 11‐ and 12‐Mono‐ and 11,12‐Dideuteroretinoids
Authors: Bergueiro Julián , Montenegro Javier , Saá Carlos , López Susana 
Published: September 2012

AbstractAn expeditious, highly efficient approach to 11‐cis‐retinoids was achieved by semihydrogenation of a readily available 11‐yne precursor through a hydrosilylation–protodesilylation protocol. The complete chemo‐, regio‐, and syn‐stereoselectivity of the method also allowed direct access to 11‐ and 12‐monodeutero‐, and 11,12‐dideutero‐11‐cis‐retinoids. The analogous trans series was not accessible by this route, and was synthesized by means of Hiyama coupling.
ChemInform Abstract: Solid Solutions RE16Rh11‐xZx (RE: La, Ce, Pr, Nd, Sm; Z: Ga, Zn, Cd, In, Sn, Sb, Pb, Bi) — Centrosymmetric n = 2 Variants of Parthe′s Homologous Series A5n+6B3n+5.
Authors: Tappe Frank , Schappacher Falko M. , Langer Thorsten , Schellenberg Inga , Poettgen Rainer 
Published: September 2012

AbstractThe title solid solutions are prepared by high‐frequency melting of the elements in sealed Ta ampules and characterized by powder XRD.
ChemInform Abstract: Li0.97FeII0.79Fe III0.15(PO4), a New Oxidized Triphylite‐Type Phosphate.
Authors: Dal Bo Fabrice , Hatert Frederic 
Published: September 2012

AbstractThe mixed valence title compound is hydrothermally synthesized from an aqueous mixture of Li3PO4, FePO4, and Fe in a 4:2:1 molar ratio (autoclave, 0.1 GPa, 973 K, 7 d).
ChemInform Abstract: Synthesis, Crystal Structure and Properties of a New Lead Calcium Diborate.
Authors: Cao Jian , Pan Shilie , Gao Junyu , Huang Zhenjun , Dong Xiaoyu , Zhang Min 
Published: September 2012

AbstractSingle crystals of the new compound PbCaB2O5 are synthesized by the spontaneous crystallization method from a mixture of PbO, H3BO3, and CaF2 (Pt crucible, 700 °C, 1 d).
ChemInform Abstract: Pyridinium o‐Iodoxybenzoate as a Safe Form of a Famous Oxidant.
Authors: Kumanyaev Ivan M. , Lapitskaya Margarita A. , Vasiljeva Ljudmila L. , Pivnitsky Kasimir K. 
Published: September 2012

AbstractReadily available PIBX can serve as a convenient substitute of the widely‐used oxidant IBX for the oxidation of alcohols to the corresponding carbonyl compounds.
ChemInform Abstract: High‐Yielding, Versatile, and Practical [Rh(III)Cp*]‐Catalyzed ortho Bromination and Iodination of Arenes.
Authors: Schroeder Nils , Wencel‐Delord Joanna , Glorius Frank 
Published: September 2012

AbstractThe title reaction is compatible not only with the bromination and iodination of tertiary benzamide substrates bearing a variety of electron‐rich and electron‐poor groups but also with other classes of arenes, such as secondary benzamides, acetamides, and phenylpyridines.
ChemInform Abstract: Samarium‐Promoted Asymmetric Aldol—Tishchenko Reaction: Synthesis of Amino Acid‐Derived 4‐Amino‐1,3‐diols.
Authors: Rodriguez‐Solla Humberto , Concellon Carmen , Tuya Paula , Garcia‐Granda Santiago , Diaz M. Rosario 
Published: September 2012

AbstractEnantiopure title compounds (V) are obtained after reduction of aldol—Tishchenko adducts formed with moderate diastereoselectivity from chiral amino ketones (I) and aliphatic aldehydes.
ChemInform Abstract: New Chiral Phase‐Transfer Catalysts Possessing a 6,6′‐Bridged Ring on the Biphenyl Unit: Application to the Synthesis of α,α‐Dialkyl‐α‐amino Acids.
Authors: Kubota Yasushi , Shirakawa Seiji , Inoue Tsutomu , Maruoka Keiji 
Published: September 2012

AbstractPowerful chiral biphenyl catalysts possessing a 6,6′‐bridged ring on the biphenyl unit are designed and successfully applied to the enantioselective synthesis of amino acids having a quaternary stereocenter.
ChemInform Abstract: Organocatalyzed Isomerization of α‐Substituted Alkynoates into Trisubstituted Allenoates by Dynamic Kinetic Resolution.
Authors: Inokuma Tsubasa , Furukawa Masaya , Suzuki Yusuke , Kimachi Tetsutaro , Kobayashi Yusuke , Takemoto Yoshiji 
Published: September 2012

AbstractThe isomerization of alkynoates is smoothly catalyzed by a bicyclic guanidine—diamine catalyst to afford the trisubstituted allenoates (II) in high enantioselectivities (up to 94% e.e.).
ChemInform Abstract: S‐Benzyl Isothiouronium Chloride as a Recoverable Organocatalyst for the Direct Reductive Amination of Ketones with Hantzsch Ester.
Authors: Nguyen Quynh Pham Bao , Kim Taek Hyeon 
Published: September 2012

AbstractThe procedure is successful for various ketones and aromatic amines to afford the desired products in moderate to good yield.
ChemInform Abstract: Chemoselective Suzuki—Miyaura Coupling of Bromophenyl‐Substituted Bromoallenes with Arylboronic Acids.
Authors: Du Xin , Liu Xuesong , Xu Liang , Jiang Wenfeng , Bao Ming , He Ren 
Published: September 2012

AbstractIt discovered that reaction of allenes of type (I) with arylboronic acids under the conditions shown exclusively takes place at the brominated double bond and not at the bromophenyl substituent.
ChemInform Abstract: Sonogashira Reactions of 2,3,4,5‐Tetrabromofuran: Synthesis of 2,3,4,5‐Tetraalkynylfurans, 2,3,5‐Trialkynylfurans and 2,5‐Dialkynylfurans.
Authors: Malik Imran , Ahmad Zeeshan , Reimann Sebastian , Nawaz Muhammed , Patonay Tamas , Langer Peter 
Published: September 2012

AbstractPd/Cu‐catalyzed regioselective Sonogashira cross‐coupling of (I) with acetylenes using diisopropylamine as base and solvent provides di‐, tri‐ and tetraalkynylated furans.
ChemInform Abstract: Synthesis of Functionalized 2,5‐Diaminofurans by Reaction of Isocyanides, Acetylenic Esters and Acid Anhydrides.
Authors: Hassanabadi Alireza , Mosslemin Mohammad H. , Anary‐Abbasinejad Mohammad , Ghalehbandy Sharminehsadat 
Published: September 2012

AbstractThe advantages of the presented protocol are mild reaction conditions, short reaction time and the tolerance of various functional groups.
ChemInform Abstract: Hindered Biaryls by C—H Coupling: Bisoxazoline‐Pd Catalysis Leading to Enantioselective C—H Coupling.
Authors: Yamaguchi Kazuya , Yamaguchi Junichiro , Studer Armido , Itami Kenichiro 
Published: September 2012

AbstractThe first enantioselective biaryl coupling through C—H bond functionalization is demonstrated [cf.
ChemInform Abstract: Potassium tert‐Butoxide Promoted Cycloaddition Reaction for the Synthesis of 1,5‐Disubstituted 1,2,3‐Triazoles from Aromatic Azides and Trimethylsilyl‐Protected Alkynes.
Authors: Wu Luyong , Chen Yuxue , Tang Mi , Song Xinming , Chen Guangying , Song Xiaoping , Lin Qiang 
Published: September 2012

AbstractOptimized conditions are developed for the desilylation of the starting alkynes and subsequent cycloaddition with aromatic azides to produce triazoles regioselectively.
ChemInform Abstract: Chemoselective Suzuki—Miyaura Reactions of 4‐Trifluoromethylsulfonyloxy‐6‐bromocoumarin.
Authors: Akrawi Omer A. , Nagy Gergo Z. , Patonay Tamas , Villinger Alexander , Langer Peter 
Published: September 2012

AbstractA broad spectrum of biologically interesting mono‐ and diarylated coumarin derivatives is prepared.
ChemInform Abstract: A Convenient Synthesis of (1H‐Azol‐1‐yl)piperidines.
Authors: Shevchuk Nadiia V. , Liubchak Kostiantyn , Nazarenko Kostiantyn G. , Yurchenko Aleksandr A. , Volochnyuk Dmitriy M. , Grygorenko Oleksandr O. , Tolmachev Andrey A. 
Published: September 2012

AbstractA convenient two‐step sequence including heteroarylation of azoles and subsequent reduction allows the synthesis of various N‐heterocyclic systems as potential drug candidates.
ChemInform Abstract: Efficient Synthesis of N‐Substituted 4‐Arylquinoline Derivatives Using ZnCl2 or ZrO2.
Authors: Zonouzi Afsaneh , Mirzazadeh Roghieh , Peivandi Azadeh , Dehdari Shahrzad 
Published: September 2012

AbstractA new modification of Hantzsch dihydropyridine synthesis is given using either zinc chloride or zirconium(IV) oxide as inexpensive Lewis acid catalysts.
ChemInform Abstract: Gold‐Catalyzed Cascade Reaction of Hydroxy Enynes for the Synthesis of Oxanorbornenes and Naphthalene Derivatives.
Authors: Song Xian‐Rong , Xia Xiao‐Feng , Song Qing‐Bao , Yang Fang , Li Ying‐Xiu , Liu Xue‐Yuan , Liang Yong‐Min 
Published: September 2012

AbstractTreatment of the enynes with [bmim]AuCl4 results in efficient formation of oxanorbornene derivatives.
ChemInform Abstract: Synthesis of Novel Tricyclic and Tetracyclic Sultone Scaffolds via Intramolecular 1,3‐Dipolar Cycloaddition Reactions.
Authors: Ghandi Mehdi , Taheri Abuzar , Bozcheloei Abolfazl Hasani , Abbasi Alireza , Kia Reza 
Published: September 2012

AbstractThis are the first examples for cycloadditions in which the dipolarophile is tethered to the dipole moiety by a sulfonate link.
ChemInform Abstract: Synthesis and Structure Analysis of 1‐(2‐Chlorobenzoyl)‐3,6‐diphenyl‐1,4‐dihydro‐1,2,4,5‐tetrazine.
Authors: Rao Guo‐Wu , Zhang Li‐Ling , Li Xiao‐Min 
Published: September 2012

AbstractThe title reaction leads to the 1,4‐dihydro rather than the 1,2‐dihydro derivative.
ChemInform Abstract: An Efficient One‐Pot Synthesis, Structure, Antimicrobial and Antioxidant Investigations of Some Novel Quinolyldibenzo[b,e][1,4]diazepinones.
Authors: Parmar Narsidas J. , Barad Hitesh A. , Pansuriya Bhavesh R. , Teraiya Shashikant B. , Gupta Vivek K. , Kant Rajni 
Published: September 2012

AbstractA catalyst‐ and solvent‐free procedure for the one‐pot synthesis of novel N‐allylated quinolyldibenzodiazepinones via a multicomponent reaction is developed.
ChemInform Abstract: Synthesis of Novel Pyrido[1,2‐b][2,4]benzodiazepine Derivatives.
Authors: Kovtunenko Volodymyr O. , Potikha Lyudmila M. , Sypchenko Volodymyr V. , Zubatyuk Roman I. , Shishkin Oleg V. 
Published: September 2012

AbstractThe title compounds (IV) are stable on heating with Ac2O, Ph—NO2, benzaldehydes and amines but undergo cleavage in the presence of MeONa.
ChemInform Abstract: Synthesis of N‐Aryl‐1,5,3‐dithiazepanes and N‐Aryl‐1,5,3‐dithiazocanes in the Presence of Samarium‐ and Cobalt‐Containing Catalysts.
Authors: Murzakova N. N. , Prokof'ev K. I. , Tyumkina T. V. , Ibragimov A. G. 
Published: September 2012

AbstractEfficient procedures for the synthesis of the title compounds (IV) are developed using cyclocondensation as well as by transamination processes.
ChemInform Abstract: DAST Mediated Preparation of β‐Fluoro‐α‐aminophosphonates.
Authors: Kazmierczak Marcin , Koroniak Henryk 
Published: September 2012

AbstractA new and convenient route to β‐fluoro‐α‐aminophosphonates (IV) using diethylaminosulfur trifluoride for nucleophilic fluorination is described.
ChemInform Abstract: Synthesis of the Antitrypanosomal Agent (.+‐.)‐Hydroxyanthecotulide by Cr(II)‐Catalyzed Allylation and Meyer—Schuster Rearrangement.
Authors: Hodgson David M. , Talbot Eric P. A. , Clark Barry P. 
Published: September 2012

AbstractA novel strategy for the stereocontrolled synthesis of anti‐ and syn‐hydroxyanthecotulide is presented.
ChemInform Abstract: Lewis Acids as α‐Directing Additives in Glycosylations by Using 2,3‐O‐Carbonate‐Protected Glucose and Galactose Thioglycoside Donors Based on Preactivation Protocol.
Authors: Geng Yiqun , Qin Qi , Ye Xin‐Shan 
Published: September 2012

AbstractIt is found that the carbohydrates can undergo highly α‐selective glycosylations in the presence of BF3 or SnCl4.
Arene–RuII Complexes of Curcumin Exert Antitumor Activity via Proteasome Inhibition and Apoptosis Induction
Authors: Bonfili Laura , Pettinari Riccardo , Cuccioloni Massimiliano , Cecarini Valentina , Mozzicafreddo Matteo , Angeletti Mauro , Lupidi Giulio , Marchetti Fabio , Pettinari Claudio , Eleuteri Anna Maria 
Published: September 2012

AbstractOrganometallic ruthenium(II) complexes of general formula [(η6‐arene)Ru(curcuminato)Cl], with arene being p‐iPrC6H4Me (1), C6H6 (2), and C6Me6 (3), were synthesized, characterized, and evaluated for their antitumor effects. Specifically, we explored their ability to regulate the proteasome, a validated pharmacological target in cancer treatment. Ruthenium complexes inhibited isolated proteasomes to various extents, with the biological activity of these complexes depending on the nature of the bound arene; in particular, [(η6‐arene)Ru(curcuminato)Cl] 2 suppressed proteasomal activities more potently than 1, 3, or free curcumin. Each complex also inhibited proteasomes in cultured colon cancer cells and consequently triggered apoptosis, with the [(η6‐benzene)Ru(curcuminato)Cl] complex 2 being the most active. The influence on the oxidative status of HCT116 cells and the DNA binding ability of the [(η6‐arene)Ru(curcuminato)Cl] complexes were studied. Complex 2 showed the highest antioxidant capacity; moreover, complexes 1 and 2 were shown to bind isolated DNA with higher affinity (up to threefold) than free curcumin. Collectively, our results demonstrate that the complexation of curcumin with ruthenium(II) is a promising starting point for the development of curcumin‐based anticancer drugs.
Highly Reproducible Surface‐Enhanced Raman Spectra on Semiconductor SnO2 Octahedral Nanoparticles
Authors: Jiang Li , Yin Penggang , You Tingting , Wang Hua , Lang Xiufeng , Guo Lin , Yang Shihe 
Published: September 2012

AbstractHighly reproducible surface‐enhanced Raman scattering (SERS) spectra are obtained on the surface of SnO2 octahedral nanoparticles. The spot‐to‐spot SERS signals show a relative standard deviation (RSD) consistently below 20 % in the intensity of the main Raman peaks of 4‐mercaptobenzoic acid (4‐MBA) and 4‐nitrobenzenethiol (4‐NBT), indicating good spatial uniformity and reproducibility. The SERS signals are believed to mainly originate from a charge‐transfer (CT) mechanism. Time‐dependent density functional theory (TD‐DFT) is used to simulate the SERS spectrum and interpret the chemical enhancement mechanism in the experiment. The research extends the application of SERS and also establishes a new uniform SERS substrate.
Organic contaminants of emerging concern in sediments and flatfish collected near outfalls discharging treated wastewater effluent to the Southern California Bight
Authors: Maruya Keith A. , Vidal-Dorsch Doris E. , Bay Steven M. , Kwon Jeong W. , Xia Kang , Armbrust Kevin L. 
Published: September 2012

Abstract
To investigate the occurrence and bioaccumulation of organic contaminants of emerging concern (CECs) near four major wastewater ocean outfalls in the Southern California Bight, more than 75 pharmaceutical and personal care products, current-use pesticides, and industrial/commercial chemicals were analyzed in sediment and liver tissues of hornyhead turbot (Pleuronichthys verticalis) using gas and liquid chromatography–mass spectrometry. Although most CECs targeted were infrequently detected or not detectable, triclosan, 4-nonylphenol (4-NP) and bis(2-ethylhexylphthalate) were detected in all sediments at median (maximum) concentrations of 5.1 (8.6), 30 (380), and 121 (470) µg/kg, respectively. In the liver, 4-NP and polybrominated diphenyl ether (PBDE) congeners 47 and 99 were detected in &gt;90% of samples at median (maximum) concentrations of 85 (290) and 210 (480) µg/kg, respectively. The sedative diazepam was detected in all liver samples, but was infrequently detected in sediments. Sediment and liver concentrations across outfall locations ranged over several orders of magnitude and were elevated relative to a reference site. Relative to sediment, accumulation in liver of PBDEs 47 and 99 was comparable to that for legacy organochlorines, confirming their high bioaccumulation potential and suggesting their inclusion in future tissue monitoring studies. Mean tissue PBDE and diazepam concentrations were higher in livers from male versus female P. verticalis, suggesting that gender differences also be considered in designing such studies. Environ. Toxicol. Chem. 2012; 31: 2683–2688. © 2012 SETAC
Annual and seasonal evaluation of reproductive status in hornyhead turbot at municipal wastewater outfalls in the Southern California Bight
Authors: Forsgren Kristy L. , Bay Steven M. , Vidal-Dorsch Doris E. , Deng Xin , Lu Guanghua , Armstrong Jeff , Gully Joseph R. , Schlenk Daniel 
Published: September 2012

Abstract
Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were collected from discharge areas, farfield stations, and a reference location in the SCB to examine spatial and temporal patterns. Fish from the Orange County outfall farfield site were younger and less sexually mature than fish from other sites. The sex ratio was skewed in some fish from outfall sites as well as from the Dana Point reference site. However, no consistent pattern in sex ratio was present over time. Low-level induction of vitellogenin was frequently observed in male fish from all sites, suggesting widespread exposure to estrogenic compounds, but did not appear to impact reproductive function as there was no incidence of gonad abnormalities (ova-testis). Analysis of historical hornyhead turbot trawl data indicated that populations are either increasing or stable in the SCB; thus, environmental estrogen exposure was not adversely impacting fish abundance. Additional research is needed to determine the cause of the estrogenic response in hornyhead turbot and whether the source of the estrogenic compounds is a consequence of historical contamination or of ongoing sources or representative of baseline characteristic of this species. Environ. Toxicol. Chem. 2012; 31: 2701–2710. © 2012 SETAC
Effect of chronic exposure to zinc in young spats of the Pacific oyster (Crassostrea gigas)
Authors: Devos Alexandre , Voiseux Claire , Caplat Christelle , Fievet Bruno 
Published: September 2012

Abstract
The marine coastal environment is exposed to a mixture of environmental pollutants of anthropogenic origin, resulting in chronic low concentrations of contaminants. As a consequence, most coastal marine species are exposed to low doses of such pollutants during their entire life. Many marine species live for years in their natural environment, whereas they do not under laboratory exposure conditions. Using early stages of development in laboratory work allows animals to be chronically exposed from an early age over a reasonable experiment period. In the present study, the authors investigated the effect of chronic exposure to zinc in spats of the Pacific oyster (Crassostrea gigas), from metamorphosis up to 10 weeks. The authors investigated integrated biological endpoints that would account for the apparent general health of the animals as well as molecular markers showing more subtle effects that could potentially go unnoticed at a biologically integrated level. The authors measured in parallel both growth and the transcriptional level of target stress genes. Growth was monitored by image analysis of large samples to avoid high variability and ensure statistical robustness. A dose–response relationship was derived from growth data, yielding a median effective concentration (EC50) of 7.55 µM. Stress genes selected on the basis of available RNA sequences in C. gigas included genes involved in chaperone proteins, oxidative stress, detoxification, and cell cycle regulation. Out of nine stress target genes, only metallothionein displayed overexpression in response to high levels of zinc. Environ. Toxicol. Chem. 2012; 31: 2841–2847. © 2012 SETAC
Quantifying the effect of nanoparticles on As(V) ecotoxicity exemplified by nano-Fe2O3 (magnetic) and nano-Al2O3
Authors: Hu Ji , Wang Demin , Forthaus Brett E. , Wang Jianmin 
Published: September 2012

Abstract
Nano-Fe2O3 (magnetic) and nano-Al2O3 are increasingly used in biomedical fields for cellular labeling and drug delivery, and in the industry as catalysts. However, they may also serve as carriers of toxic contaminants and negatively impact the environment and human health. In the present study, Ceriodaphnia dubia was used to assess the toxicity of these nanoparticles (NPs) with and without the presence of background arsenic(V) (As[V]). The results showed that although these NPs alone did not exhibit significant toxicity in the experimental concentration range, they could significantly enhance the toxicity of As(V). The accumulation of As(V) on nano-Fe2O3 (m) and nano-Al2O3, as well as the uptake of these NPs in C. dubia, were verified. An inverse relationship between the median lethal concentration (LC50) of the soluble As(V) and the accumulation of NPs in C. dubia was developed. Therefore, the uptake of As(V)-loaded NPs in C. dubia played a key role in enhancing As(V) toxicity. Environ. Toxicol. Chem. 2012; 31: 2870–2876. © 2012 SETAC
An approach for calculating a confidence interval from a single aquatic sample for monitoring hydrophobic organic contaminants
Authors: Matzke Melissa M. , Allan Sarah E. , Anderson Kim A. , Waters Katrina M. 
Published: September 2012

Abstract
The use of passive sampling devices (PSDs) for monitoring hydrophobic organic contaminants in aquatic environments can entail logistical constraints that often limit a comprehensive statistical sampling plan, thus resulting in a restricted number of samples. The present study demonstrates an approach for using the results of a pilot study designed to estimate sampling variability, which in turn can be used as variance estimates for confidence intervals for future n = 1 PSD samples of the same aquatic system. Sets of three to five PSDs were deployed in the Portland Harbor Superfund site for three sampling periods over the course of two years. The PSD filters were extracted and, as a composite sample, analyzed for 33 polycyclic aromatic hydrocarbon compounds. The between-sample and within-sample variances were calculated to characterize sources of variability in the environment and sampling methodology. A method for calculating a statistically reliable and defensible confidence interval for the mean of a single aquatic passive sampler observation (i.e., n = 1) using an estimate of sample variance derived from a pilot study is presented. Coverage probabilities are explored over a range of variance values using a Monte Carlo simulation. Environ. Toxicol. Chem. 2012; 31: 2888–2892. © 2012 SETAC