bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Practical Cu(OAc)2/TEMPO‐Catalyzed Selective Aerobic Alcohol Oxidation under Ambient Conditions in Aqueous Acetonitrile.
Authors: Jiang Jian‐An , Du Jia‐Lei , Wang Zhan‐Guo , Zhang Zhong‐Nan , Xu Xi , Zheng Gan‐Lin , Ji Ya‐Fei
Published: July 2014

A practical Cu(II)/TEMPO‐catalyzed process oxidizes primary and secondary alcohols to the corresponding carbonyl compounds using air as the terminal oxidant.
ChemInform Abstract: Spontaneous Formation of PMB Esters Using 4‐Methoxybenzyl‐2,2,2‐trichloroacetimidate.
Authors: Shah Jigisha P. , Russo Christopher M. , Howard Kyle T. , Chisholm John D.
Published: July 2014

A mild method for the conversion of a variety of carboxylic acids to their Pmb‐esters by uncatalyzed reaction with trichloroacetimidate (II) is presented.
ChemInform Abstract: Regenerative Glycosylation under Nucleophilic Catalysis.
Authors: Nigudkar Swati S. , Stine Keith J. , Demchenko Alexei V.
Published: July 2014

Glycosylation in the presence of difluorooxindole proceeds in a regenerative manner, allowing to use only catalytic amounts of this activator.
ChemInform Abstract: Direct Carboxylation of Allylic Halides with Carbon Dioxide in the Presence of Indium.
Authors: Miao Bukeyan , Ma Shengming
Published: July 2014

This highly regioselective title reaction tolerates a wide range of functional groups and gives a novel and convenient access to β,γ‐unsaturated carboxylic acids.
ChemInform Abstract: Synthesis of Thiohydroxamic Acids and Thiohydroximic Acid Derivatives.
Authors: Lemercier Berenice C. , Pierce Joshua G.
Published: July 2014

The conversion of the thiohydroxamic acids (II) to their derivatives via allylation and acylation can be performed in a one‐pot manner [cf.
ChemInform Abstract: Nickel‐Catalyzed Mizoroki—Heck Reaction of Aryl Sulfonates and Chlorides with Electronically Unbiased Terminal Olefins: High Selectivity for Branched Products.
Authors: Tasker Sarah Z. , Gutierrez Alicia C. , Jamison Timothy F.
Published: July 2014

Transformation of aryl mesylates, tosylates and chlorides gives the products in lower yields in comparison to the corresponding triflates.
ChemInform Abstract: A Highly Selective Synthesis of 1‐Substituted (E)‐Buta‐1,3‐dienes with 4,4,5,5‐Tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane as Building Block.
Authors: Szudkowska‐Fratczak Justyna , Ryba Aline , Franczyk Adrian , Walkowiak Jedrzej , Kubicki Maciej , Pawluc Piotr
Published: July 2014

In the reaction the Suzuki—Miyaura cross‐coupling pathway prevails compared to the also possible Heck coupling and (E)‐buta‐1,3‐dienes are predominantly formed.
ChemInform Abstract: Catalyst Free, Base Free Microwave Irradiated Synthesis of Aryl Nitrites from Potassium Aryltrifluoroborates and Bismuth Nitrate.
Authors: Al‐Masum Mohammad , Welch Rebecca L.
Published: July 2014

Microwave heating of a mixture of aryltrifluoroborates with bismuth nitrate in toluene offers an interesting synthesis of nitrobenzene derivatives without the need of any base or catalyst.
ChemInform Abstract: Installation of Protected Ammonia Equivalents onto Aromatic & Heteroaromatic Rings in Water Enabled by Micellar Catalysis.
Authors: Isley Nicholas A. , Dobarco Sebastian , Lipshutz Bruce H.
Published: July 2014

The arylation of carbamates (I), ureas (IX), and sulfonamides (XI) in an aqueous solution of TPGS‐750‐M surfactant is elaborated.
ChemInform Abstract: The First Used Half Sandwich Ruthenium(II) Complexes Bearing Benzimidazole Moiety for N‐Alkylation of Amines with Alcohols.
Authors: Demir Serpil , Coskun Feyzullah , Oezdemir Ismail
Published: July 2014

Half sandwich ruthenium(II) complexes (I) are synthesized and applied to the N‐alkylation of anilines with benzyl alcohols.
ChemInform Abstract: A Mild and Highly Efficient Laccase‐Mediator System for Aerobic Oxidation of Alcohols
Authors: Zhu Chenjie , Zhang Zhi , Ding Weiwei , Xie Jingjing , Chen Yong , Wu Jinglan , Chen Xiaochun , Ying Hanjie
Published: July 2014

25 examples
ChemInform Abstract: Highly Efficient Aerobic Oxidation of Various Amines Using Pd3Pb Intermetallic Compounds as Catalysts.
Authors: Furukawa Shinya , Suga Akifusa , Komatsu Takayuki
Published: July 2014

Primary and secondary amines are oxidized to imines in the presence of oxygen.
ChemInform Abstract: Metal‐Free Oxidative Amidation of 2‐Oxoaldehydes: A Facile Access to α‐Ketoamides.
Authors: Mupparapu Nagaraju , Khan Shahnawaz , Battula Satyanarayana , Kushwaha Manoj , Gupta Ajai Prakash , Ahmed Qazi Naveed , Vishwakarma Ram A.
Published: July 2014

Primary alkyl amines including aniline do not give the desired products.
ChemInform Abstract: Efficient C—S Cross‐Coupling of Thiols with Aryl Iodides Catalyzed by Cu(OAc)2·H2O and 2,2′‐Biimidazole.
Authors: Zong Chenglong , Liu Jianli , Chen Shengyan , Zeng Runsheng , Zou Jianping
Published: July 2014

A highly efficient, mild, simple, and economically attractive copper catalyzed C‐S Ullmann cross coupling of both aryl and alkyl thiols with aryl halides is developed.
ChemInform Abstract: An Atom‐Economic and Odorless Thia‐Michael Addition in a Deep Eutectic Solvent.
Authors: Azizi Najmedin , Yadollahy Zahra , Rahimzadeh‐Oskooee Amin
Published: July 2014

The use of a deep eutectic ionic liquid based on urea and choline chloride as the solvent and catalyst is reported for the title reaction.
ChemInform Abstract: Dihydrobiphenylenes Through Ruthenium‐Catalyzed [2 + 2 + 2] Cycloadditions of ortho‐Alkenylarylacetylenes with Alkynes.
Authors: Garcia‐Rubin Silvia , Gonzalez‐Rodriguez Carlos , Garcia‐Yebra Cristina , Varela Jesus A. , Esteruelas Miguel A. , Saa Carlos
Published: July 2014

The internal alkyne 1‐(hex‐1‐yn‐1‐yl)‐2‐vinylbenzene fails to dimerize.
ChemInform Abstract: Pd‐Catalyzed Homocoupling of Arylhydrazines via C—N Cleavage under O2.
Authors: Yao Peng
Published: July 2014

An efficient and simple new access to symmetric biaryls is given.
ChemInform Abstract: Catalytic Asymmetric Tamura Cycloadditions.
Authors: Manoni Francesco , Connon Stephen J.
Published: July 2014

The novel designed squaramide‐based catalyst (I) promotes the highly enantioselective Tamura cycloaddition of enolizable anhydrides with alkylidene oxindoles.
ChemInform Abstract: Enantioselective Intramolecular Aza‐Spiroannulation onto Benzofurans Using Chiral Rhodium Catalysis.
Authors: Iwabuchi Yoshiharu , Shibuta Takuro , Sato Shigeki , Shibuya Masatoshi , Kanoh Naoki , Taniguchi Tohru , Monde Kenji
Published: July 2014

Spirocyclisation of (I) with AcOH yields the corresponding product as a mixture of diastereomers with low enantiomeric excess for the minor one.
ChemInform Abstract: Highly Stereoselective Generation of Complex Oxy‐Bicyclic Scaffolds via an Atom‐Economic Pd(II)‐Catalyzed Hydroalkynylation, Isomerization and Diels—Alder Cycloaddition Sequence.
Authors: Shen Ruwei , Chen Ke , Deng Qiulin , Yang Jianjun , Zhang Lixiong
Published: July 2014

The new cascade reaction proceeds with high regio‐ and stereoselectivity, and tolerates a wide range of functionality and structural motifs.
ChemInform Abstract: Gold‐Catalyzed Cyclization of Diynes: Controlling the Mode of 5‐endo versus 6‐endo Cyclization — An Experimental and Theoretical Study by Utilizing Diethynylthiophenes.
Authors: Hansmann Max M. , Tsupova Svetlana , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K.
Published: July 2014

A dual‐gold catalyzed cyclization of 3,4‐diethynylthiophenes generating new heteroaromatic compounds bearing five‐membered annulated ring systems is reported.
ChemInform Abstract: Inorganic‐Base‐Mediated Hydroamination of Alkenyl Oximes for the Synthesis of Cyclic Nitrones.
Authors: Peng Xingao , Tong Benny Meng Kiat , Hirao Hajime , Chiba Shunsuke
Published: July 2014

The obtained diastereomeric mixtures of products (X) and (XII) are separable, but the stereochemistry is not assigned.
ChemInform Abstract: FeCl3 Catalyzed Regioselective C‐Alkylation of Indolylnitroalkenes with Amino Group Substituted Arenes.
Authors: Zanwar Manoj R. , Kavala Veerababurao , Gawande Sachin D. , Kuo Chun‐Wei , Huang Wen‐Chang , Kuo Ting‐Shen , Huang Hsiu‐Ni , He Chiu‐Hui , Yao Ching‐Fa
Published: July 2014

The title reaction shows good functional group tolerance and is used for the preparation of indolylquinoline derivatives [(XI) and (XIII)].
ChemInform Abstract: Enantioselective Continuous‐Flow Production of 3‐Indolylmethanamines Mediated by an Immobilized Phosphoric Acid Catalyst.
Authors: Osorio‐Planes Laura , Rodriguez‐Escrich Carles , Pericas Miquel A.
Published: July 2014

The catalyst can be recycled and used in up to 14 cycles without significant loss in activity.
ChemInform Abstract: Cationic Ir/Me‐BIPAM‐Catalyzed Asymmetric Intramolecular Direct Hydroarylation of α‐Ketoamides.
Authors: Shirai Tomohiko , Ito Hajime , Yamamoto Yasunori
Published: July 2014

Using a cationic iridium catalyst with chiral O‐linked bidentate phosphoramidite ligand, a variety of 3‐substituted 3‐hydroxy‐2‐oxindoles is synthesized through direct intramolecular hydroarylation of α‐ketoamides.
ChemInform Abstract: Ruthenium Porphyrin Catalyzed Diimination of Indoles with Aryl Azides as the Nitrene Source.
Authors: Wei Jinhu , Xiao Wenbo , Zhou Cong‐Ying , Che Chi‐Ming
Published: July 2014

High functional group tolerance and excellent chemoselectivity is observed in the 2,3‐diimination of indoles by electron‐poor aryl azides.
ChemInform Abstract: Highly Efficient Synthesis of Cyclic Carbonates from Epoxides Catalyzed by Salen Aluminum Complexes with Built‐in “CO2 Capture” Capability under Mild Conditions.
Authors: Luo Rongchang , Zhou Xiantai , Chen Shaoyun , Li Yang , Zhou Lei , Ji Hongbing
Published: July 2014

Mononuclear salen aluminum complexes are synthesized and used for title synthesis of cyclic carbonates [(III) and (V)].
ChemInform Abstract: Palladium‐Catalyzed Direct Diarylations of Pyrazoles with Aryl Bromides: A One Step Access to 4,5‐Diarylpyrazoles.
Authors: Takfaoui Abdelilah , Zhao Liqin , Touzani Rachid , Dixneuf Pierre H. , Doucet Henri
Published: July 2014

A direct Pd‐catalyzed C—H arylation with aryl bromides is developed.
ChemInform Abstract: Synthesis, Spectroscopic and Structural Studies of New 2‐Substituted 4‐ Nitroimidazoles.
Authors: Alliouche Hayette , Bouraiou Abdelmalek , Bouacida Sofiane , Bahnous Mebarek , Roisnel Thierry , Belfaitah Ali
Published: July 2014

Novel 4‐nitroimidazole derivatives (II) (9 examples) are synthesized via a MeI‐catalyzed transposition reaction of the nitro‐group.
ChemInform Abstract: Intramolecular Arylation of Benzimidazoles via Pd(II)/Cu(I) Catalyzed Cross‐Dehydrogenative Coupling.
Authors: Pereira Kyle C. , Porter Ashley L. , DeBoef Brenton
Published: July 2014

Pd‐catalyzed and microwave‐promoted intramolecular coupling of the 2‐position of benzimidazoles with tethered arylalkyl substituents forms fused polycyclic imidazole derivatives.
ChemInform Abstract: O‐Alkylation of 3‐Hydroxyisoxazoles Predominates under Mitsunobu Conditions.
Authors: Chen Lijia , Fletcher Steven
Published: July 2014

The Mitsunobu reaction of 3‐hydroxyisoxazoles with a range of alcohols is investigated with respect to selective O‐alkylation.
ChemInform Abstract: Postsynthetic Modification of IRMOF‐3 with a Copper Iminopyridine Complex as Heterogeneous Catalyst for the Synthesis of 2‐Aminobenzothiazoles.
Authors: Liu Jie , Zhang Xiaobin , Yang Jin , Wang Lei
Published: July 2014

A copper iminopyridine complex is immobilized through synthetic modification of IRMOF‐3.
ChemInform Abstract: Facile One‐Pot Synthesis of Some Novel Thiazolylpyrazole Derivatives with Antifungal Activity.
Authors: Song Ya‐Li , Yang Tao , Dong Yun‐Fang , Wu Fan , Yang Geng‐Liang
Published: July 2014

The title derivatives exhibit antifungal activity against C.
ChemInform Abstract: Facile Synthesis of 2‐Phenylquinoline‐4‐carboxamide Derivatives with Variant Structural Features.
Authors: Okawara Tadashi , Islam Rafiqul , Hossain Md. Imran , Okamoto Yoshinari , Nagamatsu Tomohisa , Anraku Kensaku
Published: July 2014

The products are potentially valuable as STAT3 inhibitors.
ChemInform Abstract: Sustainable and Selective Synthesis of 3,4‐Dihydroquinolizin‐2‐one and Quinolizin‐2‐one Derivatives via the Reactions of Penta‐3,4‐dien‐2‐ones.
Authors: Fan Xuesen , He Yan , Zhang Xinying , Wang Jianji
Published: July 2014

The reaction of pentadienones (I) with pyridines (II) at room temperature leads to a variety of 3,4‐dihydroquinolizin‐2‐ones (III), whilst the prolonged reaction at higher temperature is accompanied by an oxidation of dihydroquinolizinones with air to afford corresponding quinolizinones as sole products.
ChemInform Abstract: Synthesis of 10‐Substituted Benzo[b][1,8]naphthyridin‐5(10H)‐ones Based on the Reaction of (2‐Chloropyridin‐3‐yl)(2‐halophenyl)methanones with Primary Amines.
Authors: Kobayashi Kazuhiro , Yuba Shohei , Komatsu Toshihide
Published: July 2014

The procedure cannot be applied to the synthesis of 5‐substituted benzo[b][1,6]naphthyridin‐10(5H)‐ones due to instability of the starting (2‐chlorophenyl)(4‐chloro‐3‐pyridin‐3‐yl)methanone.
ChemInform Abstract: 4,5‐Dihydro‐1H‐pyrazolo[3,4‐d]pyrimidine Containing Phenothiazines as Antitubercular Agents.
Authors: Siddiqui Arif B. , Trivedi Amit R. , Kataria Vipul B. , Shah Viresh H.
Published: July 2014

Novel pyrazolopyrimidine derivatives (IV) (11 examples) are synthesized in high yield via a modified Biginelli multicomponent reaction and screened for their antimycobacterial activities.
ChemInform Abstract: Palladium‐Catalyzed Synthesis of Benzofurans via C—H Activation/Oxidation Tandem Reaction and Its Application to the Synthesis of Decursivine and Serotobenine.
Authors: Guo Lei , Zhang Fengying , Hu Weimin , Li Lei , Jia Yanxing
Published: July 2014

The syntheses of decursivine (X) and serotobenine (XI) are significantly shortened by the palladium‐catalyzed Heck reaction of the lactam (VII) with the corresponding aryl iodides.
ChemInform Abstract: Zinc‐Catalyzed Borylation of Primary, Secondary and Tertiary Alkyl Halides with Alkoxy Diboron Reagents at Room Temperature.
Authors: Bose Shubhankar Kumar , Fucke Katharina , Liu Lei , Steel Patrick G. , Marder Todd B.
Published: July 2014

The reaction is not significantly sensitive to air, but moderately sensitive to moisture.
ChemInform Abstract: Unique Synthetic Approach Toward a Phosphaalkene: Synthesis of a Selenium‐Substituted Phosphaalkene with Bulky Substituents.
Authors: Sugamata Koh , Sasamori Takahiro , Tokitoh Norihiro
Published: July 2014

Spectroscopic and crystallographic data of the synthesized stable phosphaalkene (II) are also provided.
ChemInform Abstract: Bicyclic Hybrid Sugars as Glycosidase Inhibitors: Synthesis and Comparative Study of Inhibitory Activities of Fused Oxa‐Oxa, Oxa‐Aza, and Oxa‐Carbasugar Hybrid Molecules.
Authors: Ansari Alafia A. , Rajasekaran Parasuraman , Khan M. Musawwer , Vankar Yashwant D.
Published: July 2014

Some new bicyclic sugar derivatives are prepared.
ChemInform Abstract: Antifungal Ether Diglycosides from Matayba guianensis Aublet
Authors: de Assis Polyana A. , Theodoro Phellipe N. E. T. , de Paula Jose E. , Araujo Ana J. , Costa‐Lotufo Leticia V. , Michel Sylvie , Grougnet Raphael , Kritsanida Marina , Espindola Laila S.
Published: July 2014

isolation of two new ether diglycosides, matayoside E (Ia) and F (Ib), with anti‐Candida activity, along with two known compounds
ChemInform Abstract: Total Synthesis of the Monoterpenoid Indole Alkaloid (.+‐.)‐Aspidophylline A.
Authors: Teng Mingxing , Zi Weiwei , Ma Dawei
Published: July 2014

The 15‐step synthesis of the title compound (.+‐.)‐(I) includes an intramolecular oxidative coupling to create the tetracyclic furoindoline motif and a [Ni(cod)2]‐mediated cyclization to install the bridged piperidine ring.
ChemInform Abstract: Total Synthesis of (.+‐.)‐Aspidophylline A.
Authors: Ren Weiwu , Wang Qian , Zhu Jieping
Published: July 2014

The synthesis features a rapid access to a fully functionalized dihydrocarbazole through 1) desymmetrization of readily available 2‐allyl‐2‐(o‐nitrophenyl)cyclohexane‐1,3‐dione; 2) an intramolecular azidoalkoxylation of an enecarbamate installing both the furoindoline ring and the azido functionality; and 3) an intramolecular Michael addition for the construction of the 2‐azabicyclo[3.3.1]nonane ring system
ChemInform Abstract: Bisindole Alkaloids Condensed with a Cyclopropane Ring. Part 1. 14,15‐Cyclopropanovinblastine (Ia) and ‐vincristine (Ib).
Authors: Szantay Csaba , Keglevich Peter , Hazai Laszlo , Dubrovay Zsofia , Dekany Miklos , Szantay Csaba Jr. , Kalaus Gyoergy
Published: July 2014

Cyclopropano‐vinblastine (Ia) has significant tumor cell inhibiting effect in leukemia, non‐small‐cell lung cancer, colon cancer, melanoma, and breast cancer.
ChemInform Abstract: New Compounds from Tabebuia avellanedae.
Authors: Tadano Takeshi , Zhang Li , Hasegawa Isao , Tatsuno Takanori , Ohta Tomihisa , Kawabata Tetsuro
Published: July 2014

Two new compounds (I) and (II) are isolated and their structures are fully characterized.
ChemInform Abstract: D‐Band Magnetism of Ag, Au, Pd and Pt Studied with XMCD
Authors: Bartolome Juan , Figueroa Adriana Isabel , Bartolome Fernando , Garcia Luis Miguel , Wilhelm Fabrice , Rogalev Andrei
Published: July 2014

Review: XMCD: X‐ray magnetic circular dichroism; 24 refs.
ChemInform Abstract: Transition Metal Complexes with Oligopeptides: Single Crystals and Crystal Structures
Authors: Lillo Vanesa , Galan‐Mascaros Jose Ramon
Published: July 2014

Review: 162 refs.
ChemInform Abstract: Coordination Chemistry‐Assembled Multicomponent Systems Built from a Gable‐Like Bis‐Porphyrin: Synthesis and Photophysical Properties
Authors: Beyler Maryline , Flamigni Lucia , Heitz Valerie , Sauvage Jean‐Pierre , Ventura Barbara
Published: July 2014

Review: 64 refs.
ChemInform Abstract: Catalysis by 1,2,3‐Triazole‐ and Related Transition‐Metal Complexes
Authors: Huang Deshun , Zhao Pengxiang , Astruc Didier
Published: July 2014

Review: 177 refs.
ChemInform Abstract: Recent Progress on Routes to Spirooxindole Systems Derived from Isatin
Authors: Xia Min , Ma Ru‐Zheng
Published: July 2014

Review: 101 refs.
ChemInform Abstract: Magnetic Nanomaterials in Catalysis: Advanced Catalysts for Magnetic Separation and Beyond
Authors: Rossi Liane M. , Costa Natalia J. S. , Silva Fernanda P. , Wojcieszak Robert
Published: July 2014

Review: 276 refs.
ChemInform Abstract: Structurally‐Modified Subphthalocyanines: Molecular Design Towards Realization of Expected Properties from the Electronic Structure and Structural Features of Subphthalocyanine
Authors: Shimizu Soji , Kobayashi Nagao
Published: July 2014

Review: [73 refs.
ChemInform Abstract: Application of Bismuth(III) Reagents and Catalysts to the Synthesis of Heterocyclic Compounds of Pharmaceutical Interest
Authors: Salvador Jorge A. R. , Pinto Rui M. A. , Silvestre Samuel M.
Published: July 2014

Review: 349 refs.
ChemInform Abstract: Recent Breakthroughs in Aqueous Cyclodextrin‐Assisted Supramolecular Catalysis
Authors: Hapiot F. , Bricout H. , Menuel S. , Tilloy S. , Monflier E.
Published: July 2014

Review: 80 refs.
ChemInform Abstract: Orientation Control over Bent‐core Smectic Liquid Crystal Phases
Authors: Kim Hanim , Kim Yun Ho , Lee Sunhee , Walba David M. , Clark Noel A. , Lee Sang Bok , Yoon Dong Ki
Published: July 2014

Review: 84 refs.
ChemInform Abstract: Regioselective Transformation of Alkynes Catalyzed by a Copper Hydride or Boryl Copper Species
Authors: Fujihara Tetsuaki , Semba Kazuhiko , Terao Jun , Tsuji Yasushi
Published: July 2014

Review: 76 refs.
ChemInform Abstract: Five‐Membered Ring Systems: With N and S (Se) Atoms
Authors: Wu Yong‐Jin , Yang Bingwei V.
Published: July 2014

Review: 56 refs.
ChemInform Abstract: Synthesis and Study on Biological Activity of Nitrogen‐Containing Heterocyclic Compounds — Regulators of Enzymes of Nucleic Acid Biosynthesis
Authors: Alexeeva I. V. , Shved A. D.
Published: July 2014

Review: 24 refs.
ChemInform Abstract: Recent Advances in Synthesis of Bacterial Rare Sugar Building Blocks and Their Applications
Authors: Emmadi Madhu , Kulkarni Suvarn S.
Published: July 2014

Review: 79 refs.
ChemInform Abstract: Recent Advances on the Enantioselective Synthesis of C‐Nucleosides Inhibitors of Inosine Monophosphate Dehydrogenase (IMPDH)
Authors: Merino Pedro , Ghirardello Mattia , Tejero Tomas , Delso Ignacio , Matute Rosa
Published: July 2014

Review: 88 refs.
ChemInform Abstract: Advancements in Solid Acid Catalysts for Biodiesel Production
Authors: Su Fang , Guo Yihang
Published: July 2014

Review: 150 refs.
ChemInform Abstract: Methodological Approaches to Development of Ecologically Safe Usage Technologies of Ferrous Industry Solid Waste Resource Potential
Authors: Pugin Konstantin Georgievich , Vajsman Jakov Iosifovich
Published: July 2014

Review: 21 refs.
ChemInform Abstract: Technology Research for the Removal of Heavy Metals from Municipal Sludge
Authors: Wang Heming , Shen Liang , Wang Heli
Published: July 2014

Review: 22 refs.
Quality lung cancer screening protects quality of life: No harm, no foul
Authors: Ostroff Jamie S.
Published: July 2014

This ancillary paper from the National Lung Screening Trial (NLST) dataset examines the impact of undergoing low‐dose spiral computed tomography (LDCT) for early detection of lung cancer on health related quality of life and state anxiety assessed at 1 and 6 months following lung screening. Outcomes are compared by screening results. Overall, the findings provide reassurance that undergoing lung cancer screening in the context of a well‐designed screening and follow‐up protocol poses little or no psychological harm or quality of life impairment to screening participants.
A minimum fluid volume of 75 mL is needed to ensure adequacy in a pleural effusion: A retrospective analysis of 2540 cases
Authors: Rooper Lisa M. , Ali Syed Z. , Olson Matthew T.
Published: July 2014

BACKGROUND

No consensus exists regarding minimum fluid volume for adequacy of benign pleural effusion specimens. Although any volume is acceptable if cytologic findings are malignant, the distinction between the absence of disease and false‐negativity is not straightforward in low‐volume specimens. Recent literature has offered conflicting results regarding what minimum volume is necessary. Moreover, no studies to date have evaluated this issue across a large series of specimens with a wide distribution of volumes. The objective of the current study was to determine the minimum volume of pleural fluid necessary for optimal cytopathological diagnosis.

METHODS

The authors identified 2540 pleural fluid specimens received between January 2000 and December 2009 and retrospectively reviewed their diagnoses and characteristics. Because of the large range of volumes (1 mL‐6500 mL), the cases were binned into 9 groups of roughly equivalent sample sizes. The malignancy fractions (percentage of cases with malignant diagnoses) were compared for each group.

RESULTS

The current study specimens had a median volume of 200 mL and an overall malignancy fraction of 20.1%. The malignancy fraction increased from 10.1% (95% confidence interval, 8.1%‐12.1%) for volumes < 5 mL to 23.3% (95% confidence interval, 20.0%‐25.8%) for volumes between 50 mL and 75 mL (P = .009). Specimens with volumes ≥ 75 mL had malignancy fractions independent of volume. In addition, ratios of benign or malignant diagnoses versus nondiagnostic and atypical results continued to increase with volume.

CONCLUSIONS

A fluid volume of ≥ 75 mL is required to eliminate the influence of specimen size on diagnostic adequacy. Although larger volumes do not appear to impact malignancy fraction, they do correlate with decreased nondiagnostic and atypical results. Cancer (Cancer Cytopathol) 2014;122:657–665. © 2014 American Cancer Society.
A distributed virtual hypercube algorithm for maintaining scalable and dynamic network overlays
Authors: Bona L. C. E. , Duarte E. P. , Fonseca K. V. O.
Published: July 2014

Network overlays support the execution of distributed applications, hiding lower level protocols and the physical topology. This work presents DiVHA: a distributed virtual hypercube algorithm that allows the construction and maintenance of a self‐healing overlay network based on a virtual hypercube. DiVHA keeps logarithmic properties even when the number of nodes is not a power of two, presenting a scalable alternative to connect distributed resources. DiVHA assumes a dynamic fault situation, in which nodes fail and recover continuously, leaving and joining the system. The algorithm is formally specified, and the latency for detecting changes and the subsequent reconstruction of the topology is proved to be bounded. An actual overlay network based on DiVHA called HyperBone was implemented and deployed in the PlanetLab. HyperBone offers services such as monitoring and routing, allowing the execution Grid applications across the Internet. HyperBone also includes a procedure for detecting groups of stable nodes, which allowed the execution of parallel applications on a virtual hypercube built on top of PlanetLab. Copyright © 2014 John Wiley & Sons, Ltd.
Insights into the issue in IPv6 adoption: A view from the Chinese IPv6 Application mix
Authors: Han Chunjing , Li Zhenyu , Xie Gaogang , Uhlig Steve , Wu Yulei , Li Liangxiong , Ge Jingguo , Liu Yunjie
Published: July 2014

Although IPv6 has been standardized more than 15 years ago, its deployment is still very limited. China has been strongly pushing IPv6, especially due to its limited IPv4 address space. In this paper, we describe measurements from a large Chinese academic network, serving a significant population of IPv6 hosts. We show that despite its expected strength, China is struggling as much as the western world to increase the share of IPv6 traffic. To understand the reasons behind this, we examine the IPv6 applicative ecosystem. We observe a significant IPv6 traffic growth over the past 3 years, with P2P file transfers responsible for more than 80% of the IPv6 traffic, compared with only 15% for IPv4 traffic. Checking the top websites for IPv6 explains the dominance of P2P, with popular P2P trackers appearing systematically among the top visited sites, followed by Chinese popular services (e.g., Tencent), as well as surprisingly popular third‐party analytics including Google. Finally, we compare the throughput of IPv6 and IPv4 flows. We find that a larger share of IPv4 flows get a high‐throughput compared with IPv6 flows, despite IPv6 traffic not being rate limited. We explain this through the limited amount of HTTP traffic in IPv6 and the presence of Web caches in IPv4. Our findings highlight the main issue in IPv6 adoption, that is, the lack of commercial content, which biases the geographic pattern and flow throughput of IPv6 traffic. Copyright © 2014 John Wiley & Sons, Ltd.
Atomic Layer Deposition of TiO2 and ZrO2 Thin Films Using Heteroleptic Guanidinate Precursors
Authors: Kaipio Mikko , Blanquart Timothee , Banerjee Manish , Xu Ke , Niinistö Jaakko , Longo Valentino , Mizohata Kenichiro , Devi Anjana , Ritala Mikko , Leskelä Markku
Published: July 2014

In this study the atomic layer deposition (ALD) of TiO2 and ZrO2 using two heteroleptic amido‐guanidinate precursors, [Ti(NEtMe)3(guan‐NEtMe)] and [Zr(NEtMe)3(guan‐NEtMe)], together with water or ozone as oxygen sources, are investigated. All processes exhibit self‐limiting growth at a deposition temperature of 275°C. The zirconium precursor especially gives high growth rates (0.8/1.0 Å per cycle with H2O/O3). The films are also relatively smooth, as determined by atomic force microscopy (AFM). The composition of the films is examined using X‐ray photoelectron spectroscopy (XPS) and time of flight elastic recoil detection analysis (TOF‐ERDA). When using ozone as the oxygen source the films present very high purity. The results are compared and discussed with respect to earlier studies on guanidinate, as well as homoleptic amido precursors.
Optimal‐Temperature‐Based Highly Efficient NiS Counter Electrode for Quantum‐Dot‐Sensitized Solar Cells
Authors: Kim Hee‐Je , Yeo Tae‐Bin , Kim Soo‐Kyoung , Rao S. Srinivasa , Savariraj A. Dennyson , Prabakar K. , Gopi Chandu V. V. M.
Published: July 2014

Metal sulfide electrodes were compared to a conventional platinum (Pt) counter electrode (CE) in quantum‐dot‐sensitized solar cells (QDSSCs), in which they were used to improve the short circuit current, fill factor, and conversion efficiency (η). We deposited optimal‐temperature‐based nickel sulfide (NiS) thin films on a fluorine‐doped tin oxide (FTO) substrate by a facile chemical bath deposition method and successfully employed them as a highly efficient CE for QDSSCs. The obtained NiS thin‐film nanoparticles exhibit high electrocatalytic performance and fast mass transfer rates toward the polysulfide electrolyte. Under the illumination of one sun (100 mW cm–2), the QDSSC with a NiS CE produces a higher η of 3.30 %, which is much higher than that of a Pt CE (1.89 %). Cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization measurements were performed to investigate the electrocatalytic activity of the NiS CE toward polysulfide electrolyte.
Synthesis of Trinuclear Heterobimetallic Cyanido‐Bridged Complexes from the Reaction of [MnI(CN)(CO)(tBuNC)4] with Transition‐Metal Chlorides
Authors: Carl Kathi , Sterzik Anke , Görls Helmar , Imhof Wolfgang
Published: July 2014

The reaction of [Mn(CN)(CO)(tBuNC)4] with MnCl2·4H2O, FeCl3·9H2O, NiCl2·6H2O, and CuCl2·2H2O, respectively, led to the formation of trinuclear heterobimetallic complexes that comprised two manganese moieties, with each coordinating the corresponding metal chloride entities through cyanide bridges. The mixed‐valence trinuclear MnI–CN–MnII–NC–MnI complex as well as the MnI–CN–NiII–NC–MnI derivative have been characterized by X‐ray structure analyses. In the case of the copper and iron compounds that exhibit easily reducable central metal ions, intramolecular electron transfer from manganese(I) to copper(II) or iron(III), respectively, is shown by the presence of metal‐to‐metal charge‐transfer (MMCT) bands as well as by EPR spectroscopy. Moreover, the iron complex shows a subsequent disproportionation, which was demonstrated by the isolation and crystallographic characterization of the reduced species with two manganese(I) complex units coordinating one FeIICl2 moiety.
Preparation of PUFA concentrates as acylglycerols via enzymatic hydrolysis of hempseed oil (Cannabis sativa L.) in a homogeneous low‐water medium
Authors: Torres‐Salas Pamela , Pedrali Alice , Bavaro Teodora , Ambrosini Serena , Marrubini Giorgio , Pappalardo Valeria M. , Massolini Gabriella , Terreni Marco , Ubiali Daniela
Published: July 2014

The growing demand for concentrated extracts of PUFA prompted us to undertake the preparation of natural glycerides containing linoleic acid and α‐linolenic acid from hempseed oil. Hempseed is an exceptionally rich source of essential FA but is still underutilized. Hempseed oil was thus submitted to a lipase‐catalyzed hydrolysis in a homogeneous medium based on oil and t‐BuOH/water. Seven commercial lipases were screened in this reaction medium, which resulted to be superior to the routinely used biphasic systems in terms of substrate/product solubility and biocatalyst stability. Lipase from Pseudomonas cepacia resulted to be sufficiently selective versus saturated FA and it was thus used to hydrolyze hempseed oil in order to obtain acylglycerols enriched with PUFA. The enzymatic reaction was scaled up and the acylglycerol components were purified and analyzed by GC‐FID. In the fraction of monoacylglycerols (yield 22%) the total amount of PUFA reached 85% (against 77% of the crude oil) whereas the content of saturated FA was negligible. The omega‐6/omega‐3 ratio of the total glyceride component (purified acylglycerols, yield 29%) was maintained in the optimal range (4.6:1) for human nutrition. Therefore, PUFA concentrates from hempseed oil here obtained in the form of natural glycerides could be considered as valuable dietary supplements.

Practical applications: The enzymatic method here described allows to directly achieve pure monoglycerides of PUFA with a potential nutraceutical use. This procedure has the advantage to occur under very mild conditions in a homogeneous medium composed of a water miscible green solvent, to be easily scalable and to rely on a standard chromatography purification step.

PUFA‐based glyceride concentrates from hempseed oil have been prepared by a fully enzymatic process in a new, homogeneous, green medium. In monoacylglycerols, content of saturated FA was significantly reduced and the omega‐6/omega‐3 ratio was maintained in the optimal range for nutritional needs.
Gold(III) Chloride and Phenylacetylene: A Catalyst System for the Ferrier Rearrangement, and O‐Glycosylation of 1‐O‐Acetyl Sugars as Glycosyl Donors
Authors: Roy Rashmi , Rajasekaran Parasuraman , Mallick Asadulla , Vankar Yashwant D.
Published: July 2014

We have developed a new catalyst system comprising AuCl3 and phenylacetylene that promotes the Ferrier rearrangement of glycals and 2‐acetoxymethylglycals with different nucleophiles, and also the O‐glycosylation of 1‐O‐acetyl sugars to obtain a variety of useful glycosides at room temperature through relay catalysis. Good anomeric selectivity was observed for the Ferrier rearrangements, whereas the O‐glycosylation of 1‐O‐acetyl sugars gave mixtures of diastereomers with moderate to excellent selectivity.
Inflammation of the thoracolumbar fascia excites and sensitizes rat dorsal horn neurons
Authors: Hoheisel U. , Mense S.
Published: July 2014

Background

Recent data show that the thoracolumbar fascia can be a source of pain. However, the spinal neuronal mechanisms underlying pain from a pathologically altered fascia are unknown. The present study aimed at finding out how dorsal horn neurons react to input from a chronically inflamed thoracolumbar fascia.

Methods

Recordings from rat dorsal horn neurons were made in the spinal segment L3. Twelve days before the recordings, the thoracolumbar fascia was inflamed by injection of complete Freund's adjuvant. Control animals received an injection of isotonic saline. In addition, behavioural experiments were carried out.

Results

Neurons in the spinal segment L3 do not normally receive input from the fascia, but 11.1% of the neurons did when the fascia was inflamed. Compared with control, the proportion of neurons having input from all deep somatic tissues rose from 10.8% to 33.3% (p < 0.02). Moreover, many neurons acquired new deep receptive fields, most of which were located in the hindlimb (p < 0.04). Surprisingly, the pressure pain threshold of the inflamed rats did not change, but they showed a reduction in exploratory activity.

Conclusions

One of the prominent findings was the appearance of new receptive fields in deep tissues of the hindlimb. Together with the expansion of the spinal target region of fascia afferents into the segment L3, the appearance of new receptive fields is a possible explanation for the spread of pain in patients with non‐specific low back pain.
Enhanced Electrochemiluminescence Performance of Ru(bpy)32+/CuO/TiO2 Nanotube Array Sensor for Detection of Amines
Authors: Yan Zhaoxiong , Xu Zhihua , Yu Jiaguo , Liu Gang
Published: July 2014

Tripropylamine (TPA) is a highly toxic and carcinogenic compound, therefore, TPA concentration in water must be monitored to protect health and the environment. In this paper, an electrochemiluminescent (ECL) sensor was fabricated by immobilising Ru(bpy)32+‐modified CuO nanoparticles (NPs) on a TiO2 nanotube array (TN) electrode. Compared to an ECL sensor fabricated by immobilising Ru(bpy)32+ on a TN only electrode, the as‐prepared sensor displays a 30 % enhanced ECL signal and a detection limit of 9.6×10−10 M at a signal‐to‐noise ratio=3 with the concentration of TPA in a range 1×10−9 to 1×10−5 M. The results from this study indicated a new approach for the enhancement of performance of ECL sensor in detecting TPA in water.
Amplified Electrochemical Immunosensor for Calmodulin Detection Based on Gold‐Silver‐Graphene Hybrid Nanomaterials and Enhanced Gold Nanorods Labels
Authors: Geng Ping , Fu Ying , Yang Meicheng , Sun Qianqian , Liu Kai , Zhang Xinai , Xu Zhiai , Zhang Wen
Published: July 2014

Calmodulin (CaM) is an important intracellular calcium‐binding protein. It plays a critical role in a variety of biological and biochemical processes. In this paper, a new electrochemical immunosensing protocol for sensitive detection of CaM was developed by using gold‐silver‐graphene (AuAgGP) hybrid nanomaterials as protein immobilization matrices and gold nanorods (GNRs) as enhanced electrochemical labels. Electrode was first modified with thionine‐chitosan film to provide an immobilization support for gold‐silver‐graphene hybrid nanomaterials. The hybrid materials formed an effective matrix for binding of CaM with high density and improved the electrochemical responses as well. Gold nanorods were prepared for the fabrication of enhanced labels (HRP‐Ab2‐GNRs), which provided a large capacity for HRP‐Ab2 immobilization and a facile pathway for electron transfer. With two‐step immunoassay format, the HRP‐Ab2‐GNRs labels were introduced onto the electrode surface, and produced electrochemical responses by catalytic reaction of HRP toward enzyme substrate of hydrogen peroxide (H2O2) in the presence of thionine. The proposed immunosensor showed an excellent analytical performance for the detection of CaM ranging from 50 pg mL−1 to 200 ng mL−1 with a detection limit of 18 pg mL−1. The immunosensor has also been successfully applied to the CaM analysis in two cancer cells (HepG2 and MCF‐7) with high sensitivity, which has shown great potency for improving clinic diagnosis and treatment for cancer study.
Electrochemical Biosensors Based on Enzymatic Reactor of Silver Solid Amalgam Powder for Measurements in Flow Systems
Authors: Josypčuk Oksana , Barek Jiří , Josypčuk Bohdan
Published: July 2014

An enzymatic reactor based on silver solid amalgam powder was suggested as the main part of biosensors in flow systems for the first time. Biosensors were tested with following enzymes: ascorbate oxidase, glucose oxidase, catalase, tyrosinase and laccase. The current response of each biosensor was optimized with respect to the detection potential, flow rate, the injection and reactor volume. Relative standard deviation for detection with the studied enzymes was found to be in the range of 0.81–2.1 %. The biosensor with the ascorbate oxidase reactor was used for determination of ascorbic acid in the vitamin tablets Celaskon.
Benchmarking dispersion and geometrical counterpoise corrections for cost‐effective large‐scale DFT calculations of water adsorption on graphene
Authors: Lorenz Marco , Civalleri Bartolomeo , Maschio Lorenzo , Sgroi Mauro , Pullini Daniele
Published: July 2014

The physisorption of water on graphene is investigated with the hybrid density functional theory (DFT)‐functional B3LYP combined with empirical corrections, using moderate‐sized basis sets such as 6‐31G(d). This setup allows to model the interaction of water with graphene going beyond the quality of classical or semiclassical simulations, while still keeping the computational costs under control. Good agreement with respect to Coupled Cluster with singles and doubles excitations and perturbative triples (CCSD(T)) results is achieved for the adsorption of a single water molecule in a benchmark with two DFT‐functionals (Perdew/Burke/Ernzerhof (PBE), B3LYP) and Grimme's empirical dispersion and counterpoise corrections. We apply the same setting to graphene supported by epitaxial hexagonal boron nitride (h‐BN), leading to an increased interaction energy. To further demonstrate the achievement of the empirical corrections, we model, entirely from first principles, the electronic properties of graphene and graphene supported by h‐BN covered with different amounts of water (one, 10 water molecules per cell and full coverage). The effect of h‐BN on these properties turns out to be negligibly small, making it a good candidate for a substrate to grow graphene on. © 2014 Wiley Periodicals, Inc.
S‐nitrosylation of Cofilin‐1 Serves as a Novel Pathway for VEGF‐Stimulated Endothelial Cell Migration
Authors: Zhang Hong‐hai , Wang Wen , Feng Lin , Yang Yingying , Zheng Jing , Huang Lan , Chen Dong‐bao
Published: July 2014

ABSTACT

Nitric oxide (NO) derived from endothelial NO synthase (eNOS) mediates vascular endothelial growth factor (VEGF)‐stimulated endothelial cytoskeleton remodeling and migration; however, the underlying mechanisms are elusive. Covalent adduction of a NO moiety (NO•) to cysteines called S‐nitrosylation (SNO) is a key NO signaling pathway. The small actin‐binding protein cofilin‐1 (CFL1) is essential for actin cytoskeleton remodeling. We investigated whether S‐nitrosylation regulates CFL1 function and endothelial cytoskeleton remodeling and migration upon VEGF stimulation. VEGF rapidly stimulated S‐nitrosylation of CFL1, which was blocked by NO Synthase inhibition and eNOS knockdown by specific eNOS‐siRNA. Cys80 and Cys139 were identified as the major SNO‐sites in CFL1 by LC‐MS/MS. The actin severing activity of recombinant SNO‐mimetic CFL1 (C80/139A DMA‐CFL1), but not SNO‐deficient CFL1 (C80/139S DMS‐CFL1), was significantly greater than that of wild‐type CFL1 (wt‐CFL1). When wt‐CFL1 and its mutants were overexpressed in endothelial cells, basal actin bound wt‐CFL1 was undetectable but significantly increased by VEGF; basal actin bound DMA‐CFL1 was readily high and basal actin bound DMS‐CFL1 was detectable but low, and both were unresponsive to VEGF. Treatment with VEGF significantly increased filamentous (F‐) actin and filopodium formation and cell migration in endothelial cells. Overexpression of wt‐CFL1 inhibited VEGF‐induced F‐actin formation. Overexpression of DMA but not DMS CFL1 decreased basal but not VEGF‐stimulated F‐actin formation. Overexpression of DMA but not DMS CFL1 suppressed VEGF‐stimulated filopodium formation and migration in endothelial cells. Thus, S‐nitrosylation of CFL1 provides a novel signaling pathway post‐NO biosynthesis via eNOS‐derived NO for endothelial cytoskeleton remodeling and migration upon VEGF stimulation. J. Cell. Physiol. 230: 406–417, 2015. © 2014 Wiley Periodicals, Inc.
Arsenic toxicity in rice with special reference to speciation in Indian grain and its implication on human health
Authors: Sinha Bishwajit , Bhattacharyya Kallol
Published: July 2014

BACKGROUND

Rice is a potentially important route of human exposure to arsenic, especially in populations with rice‐based diets. However, arsenic toxicity varies greatly with species. The initial purpose of the present study was to evaluate arsenic speciation in rice.

RESULTS

It appeared very clear from the present study that inorganic arsenic shared maximum arsenic load in rice straw while in grains it is considerably low. As species recovered from rice grain and straw are principally As(III) and As(V) with a small amount of dimethylarsenic acid (DMA) and almost non‐detectable monomethylarsonic acid (MMA) and arsenobetain (AsB). Discussion of the health risk of As in rice has largely been based on its inorganic arsenic content because these species have generally been considered to be more toxic than MMA and DMA and can be directly compared to As in drinking water, assuming equal bioavailability of inorganic As in the rice matrix and in water. The maximum dietary risk of exposure to inorganic arsenic through transplanted boro paddy in the present experiment was calculated to be almost 1706% of the provisional tolerable weekly intake for an adult of 60 kg body weight.

CONCLUSION

As species recovered from boro rice grain and straw are principally As(III) and As(V) with a small amount of DMA and almost non‐detectable MMA and AsB. Reductions in total As load through organic amendments in boro rice grain and straw samples were manifested predominately through reduced accumulations of inorganic As species [As(III) and As(V)], between which As(V) accounted for the larger share. © 2014 Society of Chemical Industry
Tailored appearance of metal coatings on microengineered polyurethane films
Authors: Erhardt C. , Hader B. , Bachmayr M. , Haupt M. , Albrecht J.
Published: July 2014

The surface topography of polyurethane films is modified by thermal imprinting of micrometer‐sized structures. A subsequent deposition of thin metallic layers produces materials with controllable visual appearance. Depending on the prepared surface structures on the used polyurethane films the resulting optical properties of the metallic layers can exhibit significant changes. A continuous variation from specular to diffuse reflection can be produced. In addition, anisotropic structures can be used to create a varying optical impression along different angles of observation. Such layered structures might be applicable for functional coatings acting as positioning system for rotatable objects in combination with a tailored appearance.
Numerische Berechnung des Verschleißes an der Dornwalze eines Ringwalzprozesses in Abhängigkeit prozessrelevanter Parameter
Authors: Behrens B.‐A. , Lütke‐Verspohl I. , Bouguecha A. , Matthias T.
Published: July 2014

Ringwalzen ist ein Umformprozess zur Herstellung nahtloser Ringe. Der Prozess kennzeichnet sich durch eine komplexe Kinematik der formgebenden Walzen und der Zentrierwalzen. Bei der Auslegung eines Ringwalzprozesses ist es erforderlich, die Vorringgeometrie und die Walzstrategie, d. h. die Vorschübe und Drehzahlen der einzelnen Walzen, so aufeinander abzustimmen, dass die geforderte Endkontur möglichst optimal erreicht wird. Mit Hilfe der FE‐Simulation können bereits vor dem Produktionsstart gezielt Optimierungen, wie z. B. die Optimierung von Walzstrategien durchgeführt und dadurch die Anzahl kostspieliger Probewalzungen auf ein Minimum beschränkt werden. Ein weiterer wichtiger Faktor ist der Verschleiß an den Walzen.

Im Vordergrund der Arbeit stehen die FE‐Modellierung eines Ringwalzprozesses und die numerische Berechnung des Verschleißes an der Dornwalze unter Variation prozessbedingter Parameter.
Identification of the minimal replicon and the origin of replication of the crenarchaeal plasmid pRN1
Authors: Berkner Silvia , Hinojosa Mery Pina , Prangishvili David , Lipps Georg
Published: July 2014

We have determined the minimal replicon of the crenarchaeal plasmid pRN1. It consists of 3097 base pairs amounting to 58% of the genome of pRN1. The minimal replicon comprises replication operon orf56/orf904 coding for a transcriptional repressor and the replication protein of pRN1. An upstream region of 64 bp that contains the promoter of the replication operon is essential as well as 166 bp of sequence downstream of the orf904 gene. This region contains a putative transcriptional terminator and a 100 nucleotides long stem–loop structure. Only the latter structure was shown to be required for replication. In addition replication was sustained when the stem–loop was displaced to another part of the pRN1 sequence. By mutational analysis we also find that the integrity of the stem–loop structure is required to maintain the replication of pRN1‐derived constructs. As similar stem–loop structures are also present in other members of the pRN family, we suggest that this conserved structural element could be the origin of replication for the pRN plasmids. Further bioinformatic analysis revealed that the domain structure of the replication protein and the presence of a similar stem–loop structure as the putative replication origin are also found in several bacteriophages.