Wide Scope (wide + scope)

Distribution by Scientific Domains

Selected Abstracts

The Synthesis of the Dimethyl Ester of Quino[4,4a,5,6- efg]-Annulated 7-Demethyl-8-deethylmesoporphyrin and Three of Its Isomers with Unprecedented peri -Condensed Quinoline Porphyrin Structures.

Molecules with Outstanding Properties as Sensitizers for Photodynamic Therapy in the Far-Red Region of the Visible Spectrum
Abstract The mesoporphyrin dimethyl ester nickel complex has been formylated via the Vilsmeier method. The four possible mono meso-formyl derivatives were isolated and characterized. Wadsworth,Emmons coupling with the anion of (diethylphosphono)acetonitrile converted these aldehydes into the four novel meso acrylonitriles. Brief treatment of these acrylonitrile systems in hot trichloroacetic acid resulted in the formation of four achiral porphyrin derivatives with unprecedented nickel complexes of quino-fused porphyrins. Subsequent removal of the nickel gave four quino-porphyrin free bases: quino[4,4a,5,6- efg]-annulated 7-demethyl-8-deethylmesoporphyrin dimethyl ester 6a, 2,-(methoxycarbonyl)quino[4,4a,5,6- jkl]-annulated 12-demethyl-13-de[2,-(methoxycarbonyl)ethyl]mesoporphyrin dimethyl ester 6b, 2,-(methoxycarbonyl)quino[4,4a,5,6- qrs]-annulated 18-demethyl-17-de(2,-methoxycarbonylethyl)mesoporphyrin dimethyl ester 6c and quino[4,5,6,7- abt]-annulated 2-demethyl-3-deethylmesoporphyrin dimethyl ester 6d. The structures of these systems were unambiguously determined via mass spectroscopy and a plethora of NMR techniques. In the same way, etioporphyrin and octaethylporphyrin were converted into the corresponding peri -condensed quinoporphyrins as products, which shows that the formation of novel pericondensed quino-porphyrins is a general reaction in the porphyrin series and will have a wide scope in this field. Also, a plausible reaction mechanism for the formation of the quinoporphyrin systems was derived. As a first test for the use of these systems as sensitizers in far-red phototherapy, the quantum yield of singlet oxygen generation by 6a in toluene was studied. This quantum yield is 0.77, which is even higher than the singlet oxygen generation by sensitized meso-tetraphenylporphyrin. Secondly, when Chinese Hamster ovary (CHO) cells were incubated in medium which contained up to 15 ,g/ml of 6a, the survival rate of the cells in the dark is complete within experimental error, showing that under these conditions, 6a is not toxic to CHO cells. When CHO cells incubated in medium containing 6a in concentrations of 1 ,g/ml and higher were treated with white light of intensity 30 mW/cm2 for 15 minutes, complete cell death was observed. Based on these facts, we expect that all four achiral systems will show very promising properties to form the basis of a photodynamic therapy in far-red light. The fact that these systems are achiral is an additional bonus for medical applications. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]

Access to Any Site-Directed Isotopomer of Methionine, Selenomethionine, Cysteine, and Selenocysteine , Use of Simple, Efficient Modular Synthetic Reaction Schemes for Isotope Incorporation

Arjan H. G. Siebum
Abstract Simple modular reaction schemes that allow access to any isotopomer of protected serine and homoserine have been worked out. These systems could be simply converted into cysteine, selenocysteine, homocysteine, homoselenocysteine, the essential amino acid methionine, and selenomethionine by Mitsunobu chemistry. These sulfur- and selenium-containing amino acids fulfil many essential roles in the living organism. In addition, homoserine could be converted in a few steps into optically active L -vinylglycine. As well as the stable isotopes 13C, 15N, 17O, and 18O, the radioactive isotopes of sulfur, selenium and carbon can also be easily introduced in a site-directed fashion. In view of the wide scope of the Mitsunobu reaction, we feel that many more important systems with the carbon skeleton of serine and homoserine should be preparable through this basic chemistry in any site-directed isotopically labeled form. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]

Experimental study of thermal effects on the mechanical behaviour of a clay

Cane Cekerevac
Abstract The paper presents the results of an experimental study of thermal effects on the mechanical behaviour of a saturated clay. The study was performed on CM clay (Kaolin) using a temperature-controlled triaxial apparatus. Applied temperatures were between 22 and 90°C. A comprehensive experimental program was carried out, including: (i) triaxial shear tests at ambient and high temperatures for different initial overconsolidation ratios; (ii) consolidation tests at ambient and high temperatures; and (iii) drained thermal heating for different initial overconsolidation ratios. The obtained results provide observations concerning a wide scope of the thermo-mechanical behaviour of clays. Test results obtained at 90°C were compared with tests performed at ambient temperature. Based on these comparisons, thermal effects on a variety of features of behaviour are presented and discussed. Focus is made on: (i) induced thermal volume change during drained heating; (ii) experimental evidence of temperature influence on preconsolidation pressure and on compressibility index; (iii) thermal effects on shear strength and critical state; and (iv) thermal effects on elastic modulus. Thermal yielding is discussed and yield limit evolution with temperature is presented. The directions of the induced plastic strains are also discussed. Several remarks on the difference in the mechanical behaviour at ambient and high temperatures conclude the paper. Copyright © 2004 John Wiley & Sons, Ltd. [source]

,Home comes first': housing and homemaking in Finnish civic educational films during 1945,1969

Minna LammiArticle first published online: 6 AUG 200
Abstract This article focuses on how the ideals of housing and homemaking were presented in post-war civic educational films in Finland. The films chosen for the article pertain to housing on a wide scope. The analysis shows that the ideals of good homes appeared to be remarkably consistent in the Finnish educational short films. The most important objective was to guide citizens towards careful household management and saving. Through rationalizing home economics, consumers were able to buy their own home. The ideal housewife had a positive attitude towards technology and rational household management. While the short films instructed people towards temperate and sensible consumption, they also created space for ordinary people to envision new opportunities for consumption. [source]

New Synthesis of Aryl and Heteroaryl N- Acylureas via Microwave-Assisted Palladium-Catalysed Carbonylation

David Liptrot
Abstract A new, practical synthesis of aryl and heteroaryl N- acylureas has been developed via palladium-catalysed carbonylation of aryl or heteroaryl halides in the presence of urea nucleophiles. A range of reactions illustrating the wide scope of this reaction was carried out under microwave irradiation, using either carbon monoxide gas in a vessel equipped with a gas inlet adapter, or molybdenum hexacarbonyl as the carbon monoxide source in standard microwave vials. The reactions proceeded in good to excellent yields. To illustrate the usefulness of this method a one-step synthesis of the important insecticide diflubenzuron is reported. [source]

Latent Profile Approach to Duration of Stalking

Katja Björklund Ph.D.
Abstract:, Stalking behavior and victim,stalker relationship are often the principal known factors in a stalking case. Thus, they are of great importance when trying to identify factors contributing to stalking duration. The present study aims to identify distinct subgroups of stalking victims based on measures of behavioral stalking dimensions. These victim subgroups, stalking dimensions, and victim,stalker relationship are examined in relation to stalking duration. Using a sample of 137 university students, latent profile analysis (LPA) revealed five distinct victim subgroups based on stalker behavior dimensions: surveillance, low-profile, social lurker, wide scope, and baseline stalkers. The subgroups were significantly related to stalking duration and explained a considerable amount of the variance along with the stalking dimensions and victim,stalker relationship. Connections to stalking literature and utility of person-orientated methods in stalking research are discussed. [source]

New nursing roles: the experience of Scotland's consultant nurse/midwives

Aim, To describe career pathways of consultant nurses/midwives and identify postholders views on key factors in role initiation, development and progression to inform future development and appointment of nurse/midwife consultants in National Health Service Scotland. Background, Nurse/midwife consultants represent the highest levels of clinical practice. Given the Scottish Executive Health Department's aim to treble numbers conditions and circumstances that enable them to flourish must be identified. Method, A postal survey was undertaken of all nurse/midwife consultants in post (n = 16). Results, Key themes emerged around factors that consultant nurse/midwives considered important including mentorship, autonomy and clinical credibility. Barriers to role delivery included lack of understanding of roles and the wide scope of some posts. Considerable variation in support, conditions of service and line management arrangements was found. Conclusions, Development of a recognized career pathway and a consistent approach to employment and support of postholders is recommended. [source]

Pharmacology and structure-activity relationships of bioactive polycyclic cage compounds: A focus on pentacycloundecane derivatives

Werner J. Geldenhuys
Abstract The chemistry of organic polycyclic cage compounds has intrigued medicinal chemists for over 50 years, yet little is published about their pharmacological profiles. Polycyclic cage compounds have important pharmaceutical applications, ranging from the symptomatic and proposed curative treatment of neurodegenerative diseases such as Parkinson's and Alzheimer's disease (e.g., amantadine and memantine), to use as anti-viral agents against influenza and the immunodeficiency virus (HIV). The polycyclic cage appears to be a useful scaffold to yield drugs with a wide scope of applications, and can be used also to modify and improve the pharmacokinetic and pharmacodynamic properties of drugs in current use. This review attempts to summarize the pharmacological profiles of polycyclic cage compounds with an emphasis on the lesser known pentacycloundecanes, homocubanes, and trishomocubanes. © 2004 Wiley Periodicals, Inc. [source]

Politically-Connected Boards and the Structure of Chief Executive Officer Compensation Packages in Taiwanese Firms,

Hsin-Yi Yu
G32; G34; J33 Abstract This paper examines the relationship between the level of political connection of the board and chief executive officer (CEO) equity-based compensation. Using a sample of Taiwanese firms, the paper provides evidence that politically connected boards grant a lower proportion of equity-based compensation to CEOs. Political intervention can reduce the proportion of equity-based compensation and, thereby, can have negative consequences for the alignment between the interests of CEOs and shareholders in firms. The findings obtained in this paper could be useful to policy-makers in emerging economies, where there is wide scope for political intervention. [source]

Rational Design of Sterically and Electronically Easily Tunable Chiral Bisimidazolines and Their Applications in Dual Lewis Acid/Brønsted Base Catalysis for Highly Enantioselective Nitroaldol (Henry) Reactions

Kuoyan Ma
Abstract A new addition to the rational design of sterically and electrically easily tunable chiral bis(imidazoline) ligands from chiral amino alcohols has been developed. Vast structural variation of chiral bis(imidazoline) ligands can be simply achieved by the choice of both the 1,2-amino alcohol and its N-1 R1 substituent. A small library of chiral bisimidazolines (1,a,h) has been constructed. The method has provided an easy and simplified route to a diverse set of air-stable and water-tolerant chiral bis(imidazoline) ligands on 10,g scales. The dual Lewis Acid/Brønsted base catalytic system generated from the (S)- 1,a/Cu(OTf)2 complex and Et3N was able to catalyze Henry reactions between aldehydes and nitromethane effectively at room temperature, and also to tolerate a wide scope of aldehydes with excellent enantiomeric excesses. Not only aromatic aldehydes but also aliphatic aldehydes afforded the nitroalcohol products, with enantiomeric excesses in the 93,98,% range. This dual catalytic system is among the most effective systems so far reported for the asymmetric parent Henry reactions. This work also represents the first members of the class of chiral bisimidazolines to have been demonstrated to achieve excellent enantioselectivities. [source]