993 resultados para 6-aryl-a-pyrones


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The synthesis of the title compound is described and results of some experiments on the degradation of patchouli alcohol are reported.

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3-Methyl-4-carboxy-2-(2′-methoxy-6′-naphthyl)cyclopenten-3-acetic acid, prepared from trans methyl 2-methyl-3-carbomethoxycyclopentanon-2-acetate and 2-methoxy-6-lithionaphthalene, on ring closure and catalytic hydrogenation gave dl-3-methoxy-17β-carboxy-1,3,5(10),6,8-estrapentaene.

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Tutkielmassa arvioidaan taajuushuutokauppojen taloudellista tehokkuutta. Tutkielmassa tarkastellaan erityisesti huutokaupan allokatiivista tehokkuutta ja sen toteutumista kahdessa huutokauppatapauksessa. Työn metodeina on historiallinen tarkastelu taajuushuutokauppojen kehityshistoriasta, toimialatarkastelu teletoimialasta, peliteoreettinen analyysi monen kohteen huutokaupan taloudellisesta tehokkuudesta sekä huutokaupassa asetettujen huutojen suuruuksien sekä määrien analysointi Suomen ja Ruotsin 2,6 GHz:n huutokauppojen osalta. Historiallisen tarkastelun tuloksena esitetään, että huutokaupat ovat taloudellisesti tehokkaampi menetelmä kuin muut taajuusjakomenetelmät: arpajaiset, hallinnollinen arviointi tai ns. ”first come first serve” –menetelmä. Matemaattisen analyysin avulla määritellään tarkasti huutokaupan tehokkuus monen kohteen huutokaupassa ja miten huutokauppamekanismilla voidaan ohjata huutokauppa tehokkaaseen lopputulemaan. 2,6 GHz:n Suomen ja Ruotsin huutokauppojen osalta johtopäätöksinä esitetään, että Ruotsin huutokaupassa todennäköisesti saavutettiin tehokas lopputulema. Suomen huutokaupan osalta esitetään, että huutokaupan taloudelliset mekanismit eivät välttämättä ohjanneet huutokauppaa tehokkaaseen lopputulemaan. Suurimpana syynä Suomen huutokaupan mahdollisesti tehottomaan lopputulemaan voitaneen pitää huutokaupassa ilmennyttä, osittain mekanismista johtunutta, vähäistä kysyntää.

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The present collection of articles is based on international conference that was held in Seinäjoki, Finland in February 2009. The topic of the conference was Effective Rural and Urban Policies and it was organised in co-operation between University Consortium of Seinäjoki, Seinäjoki Technology Centre and City of Seinäjoki. The presented papers approached the drivers of regional development from several aspects and in different kind of regional contexts across various countries. As a whole the different contributions formed a comprehensive story of those factors that are shaping the development of both rural and urban regions in global economy. The role of local innovation environment and dynamic of social processes that are ‘oiling’ the interaction between individuals within networks inspired several scholars. Also development of physical infrastructure as well as the recent development of economical models that can predict the regional impacts of large scale investments was discussed in many presentations. Clear focus with cultural and disciplinary diversity formed a fruitful basis for the conference and it was easy to learn something new. On the behalf of all organisers I would like to thank all participants of the conference and especially our foreign colleges who had travelled from distances to spend some winter days in Seinäjoki. As we all know this kind of publication does not appear automatically. All authors have done great job by finding time for writing from their busy schedules. Terttu Poranen and Jaana Huhtala have taken care of the technical editing of this publication. Sari Soini was the main organiser of conference and she has also as a editor kept the required pressure to finalize this book. In addition to University of Helsinki, conference was financially supported by the University of Vaasa, City of Seinäjoki, Lähivakuutus and Regional Centre Programme. These contributions are highly appreciated.

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Dimethyl 3-(aryl)-3,6-dihydro-2H-1,3-oxazine4,5-dicarboxylate structure assigned for the products obtained in the Bronsted acid catalyzed reaction of dimethyl but-2-ynoates with anilines and an excess of formaldehyde in methanol has been revised to methyl 1-(aryl)-3-(methoxymethyl)-4,5-dioxopyrrolidine-3-carboxylate. (C) 2010 Elsevier Ltd. All rights reserved.

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In the structure of the title compound, C27H39N3O3, each of the (4-oxopiperidin-1-yl)methyl residues adopts a flattened chair conformation (with the N and carbonyl groups being oriented to either,side of the central C-4 plane) and they occupy positions approximatelym orthogonal to the central benzene ring [C-benzene-C-C-methylene-N torsion angles 103.4 (2), -104.4 (3) and 71.9 (3)degrees]; further, two of these residues are oriented to one side of the central benzene ring with the third to the other side. In the crystal packing, supramolecular layers in the ab plane are sustained by C-H center dotcenter dot center dot O interactions.

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The crystal and molecular structure has been determined by the heavy-atom method and refined by the least-squares procedure to R= 8"3 % for 2033 photographically observed reflexions. The compound crystallizes in the space group P]" with two molecules in a unit cell of dimensions a = 11"68 + 0-02, b = 12"91 +0"02, c= 10"43+0"02/~, e= 114"7+ 1, fl=90-2+ 1 and 7,= 118.3+ 1 °. The unit cell also contains one molecule of the solvent, benzene. The 'cage' part of the molecule exhibits a large number of elongated bonds and strained internal valency angles. The bridgehead angle in the bicyclic heptane ring system is 89 °. The acetate group at C(16) and the methyl group at C(15) are cis to each other.

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All the non-H atoms of the title compound, C10H11NO2, are almost coplanar [maximum deviation = 0.040 (3) angstrom]. The crystal structure is stabilized by C-H center dot center dot center dot O hydrogen bonds.