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Synthesis of substituted bicyclo[2.2.2]octenes with cycloadditions between 3-benzoylamino-2H-pyran-2-one derivatives and maleic anhydride and further transformations with heterocyclic azine systems
No full textV okviru magistrskega dela sem sintetizirala različne že znane 3-benzoilamino-2H-piran-2-one, ki sem jih v nadaljevanju reagirala z maleinanhidridom, pri čemer je potekla dvojna Diels–Alderjeva cikloadicijska reakcija, kot produkte pa sem dobila različno substituirane biciklo[2.2.2]oktenske sisteme. Preverila sem, če in na kakšen način izbira topila in sprememba reakcijske temperature vplivata na potek in izkoristek sinteze biciklo[2.2.2]oktenov.
V naslednji stopnji sem različno substituirane biciklo[2.2.2]oktenske sisteme derivatizirala z različnimi heterocikličnimi aminskimi sistemi, pri čemer so z nukleofilno substitucijo z NH skupno iz sukcinanhidridnih fragmentov nastali substituirani sukcinimidni fragmenti. Končni produkti so vsebovali po dva azinska obroča, vezana na sukcinimidni fragmenti.
Vse spojine sem analizirala s TLC, IR, MS in H NMR spektroskopijo. Analiza produktov je pokazala, da ni vsako topilo primerno za sintezo biciklo[2.2.2]oktenskih sistemov. Uspešno sem pripravila nekaj dušikovih derivatov biciklo[2.2.2]oktenskih sistemov, ki do sedaj še niso bili sintetizirani.As part of my master\u27s thesis, I synthesized various already known 3-benzoylamino-2H-pyran-2-ones, which I subsequently reacted with maleic anhydride, yielding a double Diels–Alder cycloadducts. The products obtained were variously substituted bicyclo[2.2.2]octene systems. I investigated if and how the choice of solvent and the change in reaction temperature affects the course and efficiency of the bicyclo[2.2.2]octene synthesis.
In the next stage, I derivatized various substituted bicyclo[2.2.2]octene systems with different heterocyclic amine systems. Through nucleophilic substitution with an NH group on the succinic anhydride fragments, substituted succinimide fragments were formed. The final products contained two azine rings attached to the succinimide fragments.
All compounds were analyzed using TLC, IR, MS, and H NMR spectroscopy. Product analysis showed that not every solvent is suitable for the synthesis of bicyclo[2.2.2]octene systems. I successfully prepared some nitrogen derivatives of bicyclo[2.2.2]octene systems that have not been synthesized before
Synthesis of substituted bicyclo[2.2.2]octenes with cycloadditions between 2H-pyran-2-one derivatives and maleic anhydride and further transformations with nitrogen nucleophiles
No full textZ dvakratno Diels–Alderjevo reakcijo med derivati 2H-piran-2-onov in maleinanhidridom ali N-substituiranim maleimidom lahko pripravimo substituirane biciklo[2.2.2]oktene, pri čemer pride do eliminacije molekule CO2. Biciklo[2.2.2]oktenski derivati, ki vsebujejo maleinanhidridne obroče, so zanimive tarče za nadaljnje pretvorbe z dušikovimi nukleofili. V diplomskem delu naj bi bile raziskane reakcije, s katerimi bi na biciklični skelet uvedla piridinske in druge (hetero)aromatske amine, ki služijo bodisi kot ligandi za različne katione prehodnih kovin, bodisi kot akceptorji halogenske vezi in predstavljajo pomembne strukturne fragmente pri gradnji novih 2D in 3D molekulskih arhitektur.By double Diels–Alder reaction of 2H-pyran-2-one derivatives and maleic anhydride or N-substituted maleimide, substituted bicyclo[2.2.2]octenes can be prepared via elimination of a CO2 molecule. Bicyclo[2.2.2]octene derivatives containing maleic anhydride rings are interesting targets for further conversions with nitrogen nucleophiles. In this Diploma work I intended to investigate reactions that would introduce pyridine and other (hetero)aromatic amines to the bicycle skeleton, which would serve either as ligands for various transition metal cations or as halogen bond acceptors and would thus represent important structural fragments in the construction of new 2D and 3D molecular architectures
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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