1,720,958 research outputs found
A process for the preparation of Tolterodine and intermediates thereof
No full textA process for the preparation of 6-methyl-4-(R)-phenyl-chroman-2-one and 6-methyl-4-(S)-phenyl-chroman-2-one, intermediates for the synthesis of tolterodine and its (S) enantiomer, by reaction of 6-methyl-coumarin with phenylboronic acids, esters and derivatives thereof, in the presence of chiral catalysts
Method for preparing valsartan and intermediate thereof
No full textA novel process for the preparation of valsartan and novel intermediates useful in the preparation thereof
A process for the preparation of imiquimod and intermediates thereof
No full textNovel intermediates useful for the preparation of Imiquimod and a process for the preparation of Imiquimod with the intermediates
An Efficient and Scalable Synthesis of Fexofenadine Hydrochloride
No full textAllergic rhinitis (AR) is an important allergic inflammatory disease, affecting 30-60 million people annually in the USA. The most important class of drug used in the treatment of AR is second-generation H1-antihistamines (highly selective and nonsedating drugs) like levocetirizine, desloratadine and fexofenadine. Different synthetic strategies are reported for the preparation of fexofenadine hydrochloride, but these approaches involve the formation of byproducts, either toxic or difficult to remove. The aim of this work is to find a new, efficient and scalable synthetic approach for the preparation of fexofenadine hydrochloride. The final product was assembled from methyl 2-(4-bromophenyl)-2-methylpropanoate, 3-butyn-1-ol and azacyclonol, cheap and commercially available raw materials. A key step allows to build the central oxygenated-C4-moiety through a key 5-membered intermediate, avoiding toxic or expensive reagents and catalysts. The 8-step synthesis is competitive with existing protocols, leading to fexofenadine hydrochloride in 59% overall yield
A process for the preparation of Telmisartan
No full textThe present invention relates to a process for the preparation of Telmisartan by hydroxycarbonylation of compound
of formula (V), wherein X is a substituent which can be transformed into a carboxy group by hydroxycarbonylation. The invention also relates to intermediates for the synthesis of Telmisartan
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
A concise and efficient synthesis of vildagliptin
No full textAn original synthesis of vildagliptin ((S)-1-[2-(3-hydroxyadamantan-1-ylamino)acetyl]pyrrolidine-2-carbonitrile), a powerful DPP-4 inhibitor, was developed. Vildagliptin was assembled from 3-amino-1-adamantanol, glyoxylic acid and L-prolinamide in a 4-step reaction sequence with the isolation of only two intermediates. The procedure is competitive with existing protocols, leading to vildagliptin in 63% overall yield
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