bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Synthesis and Evaluation of Novel 3a,9a‐Dihydro‐1‐ethoxycarbonyl‐1‐cyclopenteno[5,4‐b]benzopyran‐4‐ones as Antifungal Agents.
Authors: Goel Richa , Sharma Vishal , Budhiraja Abhishek , Ishar Mohan Paul S. 
Published: October 2012

AbstractTen title compounds of type (III) are prepared by 1,3‐dipolar cycloaddition reaction and tested as antifungal agents.
ChemInform Abstract: Synthesis and in vitro Antitubercular Activity of 4‐Aryl/Alkylsulfonylmethylcoumarins as Inhibitors of Mycobacterium tuberculosis.
Authors: Jeyachandran Malaichamy , Ramesh Penugonda , Sriram Dharmarajan , Senthilkumar Palaniappan , Yogeeswari Perumal 
Published: October 2012

AbstractEighteen title compounds of type (IV) are prepared and tested as inhibitors of the title species.
ChemInform Abstract: Hybrid System of Metal/Broensted Acid Relay Catalysis for the Intramolecular Double Hydroarylation and Cationic Cyclization of Diyne Diethers and Diamines.
Authors: Mo Juntae , Eom Dahan , Lee Euichul , Lee Phil Ho 
Published: October 2012

AbstractBichromenes (II), biquinolines (IV), mixed systems (VI) and dioxafluoranthenes (VIII) are generated in a rapid one‐pot reaction under mild conditions.
ChemInform Abstract: Synthesis of 6H‐Dibenzo[b,d]pyran‐6‐one Derivatives via Coumarin‐Fused Cyclohexa‐1,3‐diene Intermediates.
Authors: Chen Chao‐Yue , Zhao Yong‐Sheng , Xiang Chang‐Bing , Huang Zhi‐Zhen 
Published: October 2012

AbstractThe Pechmann dehydration reaction of cyclohexanone derivatives with phenols yields coumarin‐fused cyclohexadiene intermediates.
ChemInform Abstract: Spirocyclization by Palladium‐Catalyzed Domino Heck—Direct C—H Arylation Reactions: Synthesis of Spirodihydroquinolin‐2‐ones.
Authors: Piou Tiffany , Neuville Luc , Zhu Jieping 
Published: October 2012

AbstractThe reaction involves 5‐exo‐trig Heck cyclization followed by an intramolecular C—H functionalization and creates 2 cycles and one quaternary center in one pot.
ChemInform Abstract: Oxidant Effect of H2O2 for the Syntheses of Quinoline Derivatives via One‐Pot Reaction of Aniline and Aldehyde.
Authors: Guo Qiaoxia , Wang Wennian , Teng Weiling , Chen Liwei , Wang Yanqing , Shen Baojian 
Published: October 2012

AbstractA Lewis acid catalyzed quinoline synthesis under notably mild conditions is presented.
ChemInform Abstract: Palladium‐Catalyzed Synthesis of 4‐Alkoxycarbonyl‐3,4‐dihydroisoquinolin‐1(2H)‐ones.
Authors: Okuro Kazumi , Alper Howard 
Published: October 2012

AbstractThe process involves Mannich addition, cyclocarbonylation and decarboxylation to produce the biologically important isoquinoline structures as exclusive trans isomers.
ChemInform Abstract: A CuBr‐mediated Aerobic Reaction of 2‐Alkynylbenzaldehydes and Primary Amines: Synthesis of 4‐Bromoisoquinolones.
Authors: Too Pei Chui , Chiba Shunsuke 
Published: October 2012

AbstractA novel method is elaborated for the preparation of 4‐bromoisoquinolones (III) and (V) by copper‐mediated reaction of aldehydes (I) and (IV) with amines (II).
ChemInform Abstract: Copper(II)‐Mediated Cascade Oxidative C—C Coupling and Aromatization: Synthesis of 3‐Hydroxyphenanthridinone Derivatives.
Authors: Yu Qingzhen , Zhang Nan , Tang Yang , Lu Hang , Huang Jianhui , Wang Songqing , Du Yunfei , Zhao Kang 
Published: October 2012

AbstractOptimized conditions using air as the terminal oxidant are elaborated to prepare the biologically interesting phenanthridine derivatives.
ChemInform Abstract: Reactions of 3,3‐Diaminoacrylic Acid Derivatives with o‐Haloarenecarbonitriles. Synthesis of Fused Azines.
Authors: Igumnova E. M. , Selivanov S. I. , Dar'in D. V. , Lobanov P. S. 
Published: October 2012

AbstractReactions of diaminoacrylic acid derivatives (I) with (het)aromatic nitriles containing a labile halogen atom in the o‐position provides access to fused diaminoazides via the intermediacy of the chlorine substitution products.
ChemInform Abstract: Regioselective Palladium(0)‐Catalyzed Cross‐Coupling Reactions of 5,7‐Dichloro‐1,6‐naphthyridine.
Authors: Ali Iftikhar , Hassan Zahid , Hein Martin , Falodun Abiodun , Patonay Tamas , Villinger Alexander , Langer Peter 
Published: October 2012

AbstractSite‐selective Suzuki—Miyaura reactions of starting compound (I) with arylboronic acid allow the synthesis of mono‐ and diarylated derivatives.
ChemInform Abstract: Synthesis of Dihydrobenzoimidazo[2,1‐a]isoquinolines.
Authors: Chang Meng‐Yang , Wu Ming‐Hao , Chen Yeh‐Long 
Published: October 2012

AbstractA facile one‐pot tandem condensation/hydroamination reaction of 2‐allylbenzaldehydes with 1,2‐diaminobenzenes affords the title compounds (III).
ChemInform Abstract: Application of a Cross‐Metathesis and Intramolecular Aza‐Diels—Alder Sequence to the Synthesis of trans‐2,3‐Disubstituted Tetrahydroquinolines.
Authors: Feuillastre Sophie , Pellet Vincent , Piva Olivier 
Published: October 2012

AbstractThe second step in the sequence includes the intramolecular Diels—Alder reaction of an aza‐quinodimethane unit with the unsaturated side chain to produce the target compounds as single trans‐isomers.
ChemInform Abstract: Generation of Oxodiazonium Ions. Part 3. Synthesis of [1,2,5]Oxadiazolo[3,4‐c]cinnoline‐1,5‐dioxides
Authors: Zelenov V. P. , Voronin A. A. , Churakov A. M. , Klenov M. S. , Strelenko Yu. A. , Tartakovsky V. A. 
Published: October 2012

Abstractvia reaction of 4‐(N‐nitramino)‐3‐phenylfuroxane with an Ac2O/H2SO4 system
ChemInform Abstract: Synthesis of Fused Uracils: Pyrano[2,3‐d]pyrimidines and 1,4‐Bis(pyrano[2,3‐d]pyrimidinyl)benzenes by Domino Knoevenagel/Diels—Alder Reactions.
Authors: Palasz Aleksandra 
Published: October 2012

AbstractNovel fused uracils (IV/V) and (VIII) are synthesized by domino Knoevenagel/Diels—Alder reaction between barbituric acids, aromatic aldehydes and alkyl vinyl ethers.
ChemInform Abstract: Multicomponent Synthesis of 1,2,3‐Triazol‐4‐yl‐methylthio‐3‐arylquinazolin‐4(3H)‐one Derivatives.
Authors: Koohshari Majid , Dabiri Minoo , Salehi Peyman , Bahramnejad Mahboobeh 
Published: October 2012

AbstractA novel Cu‐catalyzed three component reaction of thioxoquinazolinones (I) with propargyl bromide (II) and azides (III) is applied to the synthesis of title compounds (IV).
ChemInform Abstract: Synthesis of 1‐Substituted 4(1H)‐Quinazolinones under Solvent‐Free Conditions.
Authors: Wang Yao , Zhang Mei , Cao Shengli , Lin Huihui , Gao Man , Li Zhongfeng 
Published: October 2012

AbstractThe process which leads to quinazolinones (III) has the advantages of readily available starting materials, mild conditions, simple work‐up procedure and good yields.
ChemInform Abstract: Ionic Liquid Mediated One‐Pot Synthesis of 5‐(Trifluoromethyl)‐4,7‐dihydrotetrazolo[1,5‐a]pyrimidine Derivatives.
Authors: Li Tuan‐Jie , Yao Chang‐Sheng , Yu Chen‐Xia , Wang Xiang‐Shan , Tu Shu‐Jiang 
Published: October 2012

AbstractThe three‐component process has the advantages of short synthetic route, operational simplicity, good yields, eco‐friendliness and the recyclability of the ionic liquid.
ChemInform Abstract: General Synthetic Approach to 2‐Phenolic Adenine Derivatives.
Authors: Correira Carla , Carvalho M. Alice , Rocha Ashly , Proenca M. Fernanda 
Published: October 2012

AbstractA simple one‐pot protocol is presented for the synthesis of 2,9‐diarylpurines from imidazoles (I) and phenolic aldehydes by means of imine formation followed by cyclization and oxidation.
ChemInform Abstract: Short Synthesis of Enantiopure trans‐3‐Arylpiperazine‐2‐carboxylic Acid Derivatives via Diaza‐Cope Rearrangement.
Authors: Kwon Soon Ho , Lee Sang Min , Byun Sang Moon , Chin Jik , Kim B. Moon 
Published: October 2012

AbstractThe heterodimeric diimines are formed together with up to 13% homodimeric diimines bearing either 2 aryl or 2 cinnamaldehyde moieties.
ChemInform Abstract: Unusual Friedlander Reactions: A Route to Novel Quinoxaline‐Based Heterocycles.
Authors: Shoker Tharallah A. , Ghattass Khaled I. , Fettinger James C. , Kurth Mark J. , Haddadin Makhluf J. 
Published: October 2012

AbstractThe method allows the preparation of different types of polycyclic N‐heterocyclic systems which may be important in medicinal chemistry.
ChemInform Abstract: Ultrasound‐Assisted One‐Pot Synthesis of 1,3‐Oxazine Derivatives Catalyzed by BF3—SiO2 under Neat Conditions.
Authors: Reddy Mudumala Veeranarayana , Lim Kwon Taek , Kim Jong Tae , Jeong Yeon Tae 
Published: October 2012

AbstractAn efficient and eco‐friendly three‐component reaction of naphthol (I) with formaldehyde and primary amines is achieved in the presence of reusable BF3—SiO2 catalyst under ultrasonication.
ChemInform Abstract: Ultrasound and Microwave Assisted Rapid and Sustainable Route to Synthesis of Benzothiazine Derivatives.
Authors: Dabholkar Vijay V. , Gavande Rahul P. 
Published: October 2012

AbstractA variety of new benzothiazine derivatives is synthesized by ultrasound and microwave reactions of hydrazide (V) with 1,3‐diketo compounds containing active methylene groups.
ChemInform Abstract: Synthesis, Characterization, and Biological Evaluation of 10H‐Phenothiazines, Their Sulfones and Ribofuranosides.
Authors: Gautam Naveen , Gupta Shikha , Ajmera Neha , Gautam D. C. 
Published: October 2012

AbstractAs demonstrated for derivatives (III), (IV) and (VI), a variety of phenothiazine derivatives is prepared.
ChemInform Abstract: Generation of Oxodiazonium Ions. Part 2. Synthesis of Benzotetrazine‐1,3‐dioxides from 2‐(tert‐Butyl‐NNO‐azoxy)‐N‐nitroanilines.
Authors: Klenov M. S. , Zelenov V. P. , Churakov A. M. , Strelenko Yu. A. , Tartakovsky V. A. 
Published: October 2012

AbstractAn Ac2O/H2SO4 system is used for the synthesis of benzotetrazine‐1,3‐dioxide (II) and [1,2,5‐]oxadiazolo[3,4‐c]cinnoline‐5‐oxide (IV).
ChemInform Abstract: Generation of Oxodiazonium Ions. Part 4. Nitramine O‐Alkyl Derivatives in the Synthesis of Benzotetrazine‐1,3‐dioxides.
Authors: Klenov M. S. , Churakov A. M. , Strelenko Yu. A. , Tartakovsky V. A. 
Published: October 2012

AbstractA new method for the synthesis of benzotetrazinedioxides is developed using the cyclization of nitramine O‐alkyl derivatives (III) upon action of strong acids such as H2SO4, MeSOH, TFA or BF3·OEt2.
ChemInform Abstract: Synthesis and Anticonvulsant Activity of 9‐Alkoxy‐6,7‐dihydro‐2H‐benzo[c][1,2,4]triazolo [4,3‐a]azepin‐3(5H)‐ones.
Authors: Piao Feng‐Yu , Wei Cheng‐Xi , Han Rong‐Bi , Zhang Wen‐Bin , Zhang Wei , Jiang Ri‐Shan 
Published: October 2012

AbstractDerivative (IIIe) exhibits a strong anticonvulsant activity and antagonistic activity against seizures induced by PTZ.
ChemInform Abstract: Selective Synthesis of Seven‐ and Eight‐Membered Ring Sultams via Two Tandem Reaction Protocols from One Starting Material.
Authors: Wang Min , Wang Yanjie , Qi Yueyong , Xia Guohua , Tong Kun , Tu Jinchang , Pittman Charles U. Jr. , Zhou Aihua 
Published: October 2012

AbstractThe cyclic sulfonamide scaffolds are building blocks of important biologically active compounds.
ChemInform Abstract: Reaction of 3‐Methoxy‐2‐methylphenol with 2‐Ethoxyvinylphosphonic Dichloride
Authors: Sadykova Yu. M. , Dalmatova N. V. , Burilov A. R. , Pudovik M. A. , Dobrynin A. B. 
Published: October 2012

Abstractformation of bicyclic phosphonates (III) as major or sole products
ChemInform Abstract: Simple and Advantageneous Stereoselective Synthesis of (Z)‐Allyl Phosphonates Starting from Baylis—Hillman Adducts.
Authors: Das Biswanath , Bhunia Nisith , Damodar Kongara 
Published: October 2012

AbstractIron‐catalyzed reaction of Baylis—Hillman adducts with trialkyl phosphites provides an efficient access towards allyl phosphonates (III) with exclusive (Z)‐selectivity.
ChemInform Abstract: Synthesis and Properties of 2‐Chloro‐1,3,2‐dioxaarsolane and 1,2‐Bis(1,3,2‐dioxaarsolan‐2‐yloxy)ethane.
Authors: Kutkin A. V. , Semenova V. A. , Sizov I. I. , Sukhotskaya S. A. , Kondratenko S. M. , Kostikova N. A. , Korol'kov M. V. 
Published: October 2012

AbstractTitle compounds (II) and (III) are synthesized starting from ethylene glycol (I) using different amounts of AsCl3.
ChemInform Abstract: One‐Pot Synthesis of 5‐Arylamino‐1,3,4‐selenadiazol‐2(3H)‐ones from Arylisoselenocyanates.
Authors: Xie Yuanyuan , Yang Ping , Chen Xiaodong 
Published: October 2012

AbstractA one‐pot two‐step reaction of aryl(alkyl)isoselenocyanates with hydrazine derivatives and bis(trichloromethyl) carbonate provides an efficient access towards title selenadiazolones (III) and (V).
ChemInform Abstract: Synthesis and Properties of Triethylammonium 4‐Aryl(hetaryl) ‐3,5‐dicyano‐6‐oxo‐1,4,5,6‐tetrahydropyridine‐2‐selenolates.
Authors: Frolov K. A. , Dotsenko V. V. , Krivokolysko S. G. , Litvinov V. P. 
Published: October 2012

AbstractThe base‐mediated three‐component reaction of cyanoacetylpyrazole (I) with (het)aromatic aldehydes and cyanoselenoacetamide (III) affords the title pyridineselenolates as mixture of cis/trans‐diastereomers.
ChemInform Abstract: Magnetically Separable CuFe2O4 Nanoparticle Catalyzed C—Se Cross Coupling in Reusable PEG Medium.
Authors: Reddy K. Harsha Vardhan , Satish G. , Ramesh K. , Karnakar K. , Nageswar Y. V. D. 
Published: October 2012

AbstractUnsymmetrical diaryl selenides (III) are obtained on arylation of phenylselenyl bromide.
ChemInform Abstract: Synthesis of 2,6‐Bis(chloromethyl)‐1,4‐diselenane.
Authors: Potapov V. A. , Amosova S. V. , Volkova K. A. , Musalov M. V. , Albanov A. I. 
Published: October 2012

AbstractThe reaction of diallyl selenide with selenium dichloride is chemo‐, regio‐, and stereoselective and affords the hitherto unknown diselenane (II) in good yield.
ChemInform Abstract: Synthesis and Biological Evaluation of Laxiflorin J Derivatives as Potential Antitumor Agents.
Authors: Liu Jing‐Ping , Zhang Hong‐Bin , Huang Sheng‐Xiong , Pu Jian‐Xin , Xiao Wei‐Lie , Zhang Xue‐Ping , Xiao Wen‐Ding , Lei Chun , Sun Han‐Dong 
Published: October 2012

AbstractA series of ethereal derivatives of laxiflorin J (I) is synthesized and screened for in vitro activity against several tumor cell lines.
ChemInform Abstract: Sesquiterpene Lactone Glycosides from the Roots of Ferula varia.
Authors: Kurimoto Shin‐ichiro , Suzuki Kyoko , Okasaka Mamoru , Kashiwada Yoshiki , Kodzhimatov Olimjion Kakhkharovich , Takaishi Yoshihisa 
Published: October 2012

Abstractisolation and structure elucidation of seven new sesquiterpene lactone glycosides (I)‐(V)
ChemInform Abstract: Convenient Peptide Synthesis Using Unprotected α‐Amino Acids Containing Another Hydrophilic Moiety under Basic Conditions.
Authors: Noguchi Takuya , Jung Seunghee , Imai Nobuyuki 
Published: October 2012

AbstractPhenylalanine reacts effectively with unprotected α‐amino acids (II) containing an additional hydrophilic moiety under basic conditions via activation by ethyl chloroformate and triethylamine to afford the corresponding dipeptides.
ChemInform Abstract: Synthesis of Homotaurine and 1‐Substituted Homotaurines from α,β‐Unsaturated Nitriles.
Authors: Ma Yunhai , Xu Jiaxi 
Published: October 2012

AbstractHomotaurine (VI) and 1‐substituted derivatives (VII) are prepared by Michael addition of thioacetic acid to α,β‐unsaturated nitriles followed by reduction and oxidation.
ChemInform Abstract: A New Route to Pyrano[3,2‐a]carbazole Ring Systems and Annulated Derivatives Thereof.
Authors: Chattopadhyay Shital K. , Ghosh Debalina , Mondal Poulomi , Ghosh Sanjay K. 
Published: October 2012

AbstractA successful application of the Claisen rearrangement/isomerization/ring closing enyne metathesis for the preparation of the title skeleton is described.
ChemInform Abstract: New Indole Alkaloids from Melodinus henryi.
Authors: Kitajima Mariko , Ohara Satoko , Kogure Noriyuki , Wu Yuqiu , Zhang Rongping , Takayama Hiromitsu 
Published: October 2012

Abstractisolation and structure elucidation of melodinoxanine (I) and Nb‐methylnortetraphyllicine (II)
ChemInform Abstract: Four New Dilignans from the Roots of Wikstroemia indica
Authors: Wang Guo‐Cai , Zhang Xiao‐Li , Wang Yi‐Fei , Li Guo‐Qiang , Ye Wen‐Cai , Li Yao‐Lan 
Published: October 2012

Abstractisolation, structural elucidation and in vitro anti‐RSV activity of new dilignans (I)—(IV)
ChemInform Abstract: Synthesis of Pacidamycin Analogues via an Ugi‐Multicomponent Reaction.
Authors: Okamoto Kazuya , Sakagami Masahiro , Feng Fei , Takahashi Fumiyo , Uotani Kouichi , Togame Hiroko , Takemoto Hiroshi , Ichikawa Satoshi , Matsuda Akira 
Published: October 2012

AbstractThe four‐component Ugi‐reaction of (I), (II), (III), and (IV) is the key step in the synthesis of 3‐hydroxypacidamycin D (VII).
ChemInform Abstract: Aurone Constituents from the Flowers of Rosa rugosa and Their Biological Activities.
Authors: Gao Xuemei , Yang Liying , Shu Lidang , Shen Yanqiong , Zhang Yinjie , Hu Qiufen 
Published: October 2012

AbstractThree new aurones, namely rugaurones A (Ia), B (Ib) and C (Ic), are isolated and elucidated.
ChemInform Abstract: Complex Ammine Titanium(III) Borohydrides as Advanced Solid Hydrogen‐Storage Materials with Favorable Dehydrogenation Properties.
Authors: Yuan Feng , Gu Qinfen , Chen Xiaowei , Tan Yingbin , Guo Yanhui , Yu Xuebin 
Published: October 2012

AbstractTi(BH4)3·5NH3 (I), Li2(BH4)5·5NH3 (II), and Ti(BH4)3·3NH3 (III) are synthesized via metathesis reactions by ball milling mixtures of TiCl3·5NH3 or TiCl3·3NH3 and LiBH4 in the ratios of 1:3, 1:5, and 1:3, respectively.
ChemInform Abstract: Functional Organic Materials Based on Polymerized Liquid Crystal Monomers: Supramolecular Hydrogen‐Bonded Systems
Authors: Broer Dirk J. , Bastiaansen Cees M. W. , Debije Michael G. , Schenning Albertus P. H. J. 
Published: October 2012

AbstractReview: 40 refs.
ChemInform Abstract: Studies Toward the Total Synthesis of Naturally Occurring Pyranonaphthoquinones from Ventilago harmandiana
Authors: Kongsriprapan Sopanat , Kuhakarn Chutima , Deelertpaiboon Pramchai , Panthong Kanda , Tuchinda Patoomratana , Pohmakotr Manat , Reutrakul Vichai 
Published: October 2012

AbstractReview: 25 refs.
Functionalized Magnetizable Particles for Downstream Processing in Single‐Use Systems
Authors: Tippkötter Nils , Al‐Kaidy Huschyar , Wollny Steffen , Ulber Roland 
Published: October 2012

AbstractBiotechnological downstream processing is usually an elaborate procedure, requiring a multitude of unit operations to isolate the target component. Besides the disadvantageous space‐time yield, the risks of cross‐contaminations and product loss grow fast with the complexity of the isolation procedure. A significant reduction of unit operations can be achieved by application of magnetic particles, especially if these are functionalized with affinity ligands. As magnetic susceptible materials are highly uncommon in biotechnological processes, target binding and selective separation of such particles from fermentation or reactions broths can be done in a single step. Since the magnetizable particles can be produced from iron salts and low priced polymers, a single‐use implementation of these systems is highly conceivable. In this article, the principles of magnetizable particles, their synthesis and functionalization are explained. Furthermore, applications in the area of reaction engineering, microfluidics and downstream processing are discussed focusing on established single‐use technologies and development potential.
A Highly Sensitive and Selective Fluorescence Chemosensor for Cu2+ and Zn2+ Based on Solvent Effect
Authors: Huang Xiaobo , Miao Qian , Wang Lu , Jiao Jieming , He Xianjing , Cheng Yixiang 
Published: October 2012

AbstractA novel fluorescence chemosensor 1 based on (R)‐binaphthyl‐salen can exhibit highly sensitive and selective recognition responses toward Cu2+ by "turn‐off" fluorescence quench type in THF/H2O, and Zn2+ by "turn‐on" fluorescence enhancement type in CHCl3/CH3CN, respectively, suggesting that solvents can dramatically affect the responsive properties of salen‐based chemosensor. In addition, Cu2+ can lead to the most pronounced changes of CD spectra without the influence of solvents, which indicates this kind chemosensor can also be used as a sole Cu2+ probe based on CD spectra.
Aqueous‐Phase, Palladium‐Catalyzed Heck Reaction: The Significant Role of CN‐containing Counter Anion
Authors: Cai Yueqin , Song Gonghua , Zhou Xiaoying 
Published: October 2012

AbstractWater‐soluble diol‐functionalized imidazolium ionic liquid 1, prepared from 2,2‐bis(1‐methyl‐methyl‐imidazolium)propane‐1,3‐diol bromide, potassium hydroxide, and malononitrile, was used as an efficient phosphine‐free ligand for palladium‐catalyzed arylation of aryl halides with acrylates in aqueous phase under mild conditions. It was found that the synergistic coordinating action of diol‐functionalized imidazolium cation with CN‐containing anion played the key role in improving the activity and stability of the catalyst.
Modeling sample/patient‐specific structural and diffusional responses of cartilage using DT‐MRI
Authors: Pierce D. M. , Ricken T. , Holzapfel G. A. 
Published: October 2012

SUMMARYWe propose a new 3D biphasic constitutive model designed to incorporate structural data on the sample/patient‐specific collagen fiber network. The finite strain model focuses on the load‐bearing morphology, that is, an incompressible, poroelastic solid matrix, reinforced by an inhomogeneous, dispersed fiber fabric, saturated with an incompressible fluid at constant electrolytic conditions residing in strain‐dependent pores of the collagen–proteoglycan solid matrix. In addition, the fiber network of the solid influences the fluid permeability and an intrafibrillar portion that cannot be ‘squeezed out’ from the tissue. We implement the model into a finite element code. To demonstrate the utility of our proposed modeling approach, we test two hypotheses by simulating an indentation experiment for a human tissue sample. The simulations use ultra‐high field diffusion tensor magnetic resonance imaging that was performed on the tissue sample. We test the following hypotheses: (i) the through‐thickness structural arrangement of the collagen fiber network adjusts fluid permeation to maintain fluid pressure (Biomech. Model. Mechanobiol. 7:367–378, 2008); and (ii) the inhomogeneity of mechanical properties through the cartilage thickness acts to maintain fluid pressure at the articular surface (J. Biomech. Eng. 125:569–577, 2003). For the tissue sample investigated, both through‐thickness inhomogeneities of the collagen fiber distribution and of the material properties serve to influence the interstitial fluid pressure distribution and maintain fluid pressure underneath the indenter at the cartilage surface. Tissue inhomogeneity appears to have a larger effect on fluid pressure retention in this tissue sample and on the advantageous pressure distribution. Copyright © 2012 John Wiley & Sons, Ltd.
Spectroscopic Evidence for Polymorphic Aggregates Formed by Amyloid‐β Fragments
Authors: Guo Yangmei , Wang Jianping 
Published: October 2012

AbstractUnderstanding the structure of amyloid‐β (Aβ) aggregates is a key step towards elucidating the pathology of Alzheimer’s disease. In this work, three fragments of the Aβ1–42 protein, Aβ1–25 (DAEFRHDSGYEVHHQKLVFFAEDVG), Aβ25–35 (GSNKGAIIGLM), and Aβ33–42 (GLMVGGVVIA), were synthesized, and their aggregated structures were examined by linear infrared spectroscopy in the amide‐I (mainly the CO stretching) region. The structures of the formed aggregates were found to be both sequence and pH dependent. The results suggest that instead of forming matured fibrils, as in the case of full‐length Aβ1–42, both Aβ1–25 and Aβ33–42 form a mixture of threadlike β‐sheet fibril, soluble β‐sheet oligomer, and random coil structures. The β‐sheet conformations were found to be mainly antiparallel for the former and both parallel and antiparallel for the latter. However, the Aβ25–35 fragment was found to form assembled fibrils containing predominantly parallel β‐sheets. The conformation and morphology of the aggregates were also confirmed by circular dichroism measurements and transmission electron microscopy. Factors influencing the structures of the aggregates formed by the Aβ fragments were discussed.