1,720,959 research outputs found
Synthesis and beta1-, beta2-adrenergic receptor binding studies of 4-acylamino substituted phenoxypropanolamine and 5-acylamino substituted naphthyloxypropanolamine derivatives
No full textThe object of this study was to Investigate the beta-adrenergic receptor binding affinity of 4-acylaminophenoxypropanolamine (10-15) and 5-acylaminonaphthyloxypropanolamine (21-24) derivatives, which were prepared from 4-aminophenol (5) and 5-amino-1-naphthol (16), respectively. The in vitro beta(1)- and beta(2)-adrenergic receptor binding affinities of the newly synthesized compounds were assessed in turkey erythrocyte membrane (beta(1)) and lung homogenates of rats (beta(2)). The binding affinities were compared with that of propranolol (3) (propranolol hydrochloride, CAS 318-98-9). The compound N-[5-(3-tert-butylamino-2-hydroxy-propoxy)-naphthalen-1-yl]- acetamide (22) has beta-adrenergic receptor affinity comparable with that of propranolol and shows selectivity to beta(1)-adrenergic receptor
Synthesis of 4-(1-oxo-isoindoline) and 4-(5,6-dimethoxy-1-oxo-isoindoline)-substituted phenoxypropanolamines and their beta1-, beta2-adrenergic receptor binding studies
No full textPhenoxypropanolamines with 1-oxo-isoindoline (12–16) and 5,6-dimethoxy-1-oxo-isoindoline groups (17–20) at the para position were synthesized. beta1, beta2-Adrenergic receptor binding affinities for the synthesized compounds were tested and compared with propranolol and atenolol. It was found that the incorporation of para-amidic functionality within the 1-oxo-isoindoline ring and 5,6-dimethoxy-1-oxo-isoindoline ring system led to a high degree of cardioselectivity in the phenoxypropanolamines. Two of the compounds 12 and 20 possessed beta1-adrenergic receptor affinity comparable with that of atenolol and both showed a better cardioselectivity than
atenolol. Both 12 and 20 are undergoing further pharmacological evaluation
Synthesis of 4-(1-oxo-isoindoline)-, 4-(5,6-dimethoxy-1-oxo-isoindoline) and 4-acetamido- substituted phenoxy-3-amino-propane derivatives and their beta1-, beta2-adrenergic receptor binding studies
No full textIn continuation to our previous study of 4-(1-oxo-isoindoline)- and 4-(5,6-dimethoxy-1-oxo-isoindoline)-substituted phenoxypropanolamines as potential cardioselective beta-adrencrgic blocking agents, the synthesis of 4-(1-oxo-isoindoline) and 4-(5,6-dimethoxy-1-oxo-isoindoline)-substituted phenoxy-3-amino-propane derivatives and their beta adrenoceptor binding affinity and selectivity in turkey erythrocyte membrane (beta(1)) and lung homogenate of rats (beta(2)) is reported. Also 4-acetamido substituted derivatives are synthesized and tested. All the tested compounds exhibit better cardioselectivity, with the 4-acetamido substituted derivatives being the most cardioselective. N-[4-[3-(3,4-Dimethoxyphenylethylamino)propoxylphenyl}-1-oxo-isoindoline 7 hydrochloride shows beta(1)-adrenergic receptor binding affinity lower than propranolol, but comparable to that of atenolol with better cardioselectivity. Compound 7 has been selected for further pharmacological investigations
Synthesis of 4-(benzamide)- and 4-(phthalimide)-substituted phenoxypropanolamines and their beta1, beta2-adrenergic receptors binding studies
No full textN-[4-(2-Hydroxy-3-isopropylaminopropoxy)phenyl-l-oxo-isoindoline 3 possess a cardioselective beta-adrenergic receptor binding affinity. Herein we attempted to synthesize the unreduced compound N-[4-(2-hydroxy-3-isopropylaminopropoxy)phenyl]phthalimide 4. But, reaction of N-[4-(2,3-epoxypropoxy)phenyl]plithalimide 10 with isopropylamine opened the phthalimide ring to give N-[4-(2-hydroxy-3-isopropylaminopeopoxy)phenyll-2-isopropylcarbamoylbenzainide 12 instead of 4 as expected. While treatment of 10 with tert-buitylamine gives N-[4-(3-tert-butylamino-2-hydroxypropoxy)phenyllphthalimide 15. Further, reaction of 15 with isopropylamine opened the phtlialimide ring to yield N-[4-(3-tertbutylamino-2-hydroxypropoxy)phenyl]-2-isopropylearbainoylbenzamide 16. Also, reaction of N-[4-(2,3-epoxypropoxy)phenyl]-5,6-dimethoxyphthalimide 11 with isopropylamine affords the phthalimide ring opened analogue N-[4-(2-hydroxy3-isopropylaminopropoxy)phenyl]-2-isopropylcarbamoyl-5,6-dimethoxybeiizamide 13. Compounds 12, 13, 15 and 16 have been tested for their in vitro beta(1)- and beta(2)-adrenergic receptor binding affinity using turkey erythrocyte-membrane (01) and lung homogenate of rats (beta(2)). The percentage inhibition of [H-3]DHA binding to both beta(1)-and beta(2)-adrenergic receptors are compared with that of the standard non-selective beta-adrenergic blocking agent propranolol 1 and selective agent atenolol. All the tested compounds exhibit binding affinity to PI-adrenergic receptors at the tested concentration [10(-5) M] and most of them (12, 15, 16) exhibit cardioselectivity (selectivity ratio > 1). The dimethoxy analogue 13 shows selectivity towards beta(2)-adrenergic receptor (selectivity ratio < 1)
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
Synthesis, beta-adrenergic receptor binding and antihypertensive potential of vanillin-derived phenoxypropanolamines
No full textSynthesis of vanillin-derived phenoxypropanolamines is carried out by condensing 4-hydroxy-3-methoxybenzaldehyde (vanillin) 1 with epichlorohydrin, followed by treatment with iso-propylamine or tert-butylamine to open the epoxy ring. Percentage inhibition of [(3)H]dihydroalprenolol binding to both beta(1)- and beta(2)-adrenergic receptors by the newly synthesized compounds is assessed in vitro using turkey erythrocyte membrane (PI) and lung homogenate of rats A). Formyl derivatives 8 and 9 showed maximum inhibitory effect in binding assay and are non-selective similar to propranolol. On the other-hand, aldoxime compounds 10 and 11 have preference for PI-adrenergic receptors similar to atenolol. Also four of the compounds 8-11 are evaluated for their anti-hypertensive potential, in left renal artery ligation and fructose induced hypertension models. 4-(3-tert-Butylamino-2-hydroxy-propoxy)-3-methoxy-benzaldehydeoxime 11 shows antihypertensive effect better than propranolol
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
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