bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Potential of Aspirin in Prodrug Synthesis: A New Potential Delivery System of AZT and FLT
Authors: Zahran Magdy A. , Kovács Lajos , Sakka Ibrahim El , Pedersen Erik B. , Nielsen Claus 
Published: October 2006

AbstractAspirin (O‐acetylsalicylic acid) has been used to synthesize prodrugs of 3′‐azido‐3′‐deoxythymidine (AZT) and 3′‐deoxy‐3′‐fluorothymidine (FLT). The mixed anhydride between aspirin and trifluoroacetic acid was synthesized and reacted with AZT and FLT to give the blocked nucleosides attached through the 5′‐O position to the 2‐position of 2‐methyl‐4H‐1,3‐benzodioxin‐4‐one. The prodrugs showed the same activities against HIV‐1 in MT‐4 cells as the original drugs. Hydrolysis of the synthesized prodrugs in the growth medium, used for anti‐HIV investigations, resulted in formation of 5‐O acetylated drugs which were subsequently hydrolyzed into the original drugs.
Novel Steroidal 1,4‐Diketones and Pyridazine Derivatives as Potential Antiestrogens
Authors: Ismail Khadiga A. , El‐Tombary Alaa A. , Aboulwafa Omaima M. , Omar A‐Mohsen M. E. , El‐Rewini Safaa H. 
Published: October 2006

AbstractA series of steroidal 1,4‐diketone derivatives was synthesized by acid‐catalyzed condensation of 2‐acetylestradiol‐17β‐acetate with substituted phenylglyoxals. Conversion of the products into the corresponding pyridazine derivatives was achieved by reaction with hydrazine hydrate. The synthesized compounds were evaluated for their uterotrophic, antiuterotrophic, and antifertility activities in mature female albino rats. Among the compounds tested, the phenyl 2, p‐bromophenyl 3, and p‐methoxyphenyl 5 diketone derivatives displayed uterotrophic activity of 72%, 72%, and 91%, respectively. The gradation of antiestrogenic activity was assessed in vivo by the inhibition of the estrone‐stimulated uterine growth. Compounds 2–5 showed moderate antiestrogenic activity of 53–56%. None of the tested compounds elicited antifertility activity as assessed by the post‐coital antiimplantation activity test.
Synthesis and Antifungal Activities of Myristic Acid Analogs
Authors: Parang Keykavous , Knaus Edward E. , Wiebe Leonard I. , Sardari Soroush , Daneshtalab Mohsen , Csizmadia Ferenc 
Published: October 2006

AbstractMyristic acid analogs that are putative inhibitors of N‐myristoyl‐transferase were tested in vitro for activity against yeasts (Saccharomyces cerevisiae, Candida albicans, Cryptococcus neoformans) and filamentous fungi (Aspergillus niger). Several (±)‐2‐halotetradecanoic acids including (±)‐2‐bromotetradecanoic acid (14c) exhibited potent activity against C. albicans (MIC = 39 μM). C. neoformans (MIC = 20 μM), S. cerevisiae (MIC = 10 μM), and A. niger (MIC < 42 μM) in RPMI 1640 media. Improved synthetic methods have been developed for the synthesis of 12‐fluorododecanoic acid (12a) and 12‐chlorododecanoic acid (12c). Three novel fatty acids, 12‐chloro‐4‐oxadodecanoic acid (8a), 12‐phenoxydodecanoic acid (12i), and 11‐(4‐iodophenoxy)undecanoic acid (13d) were also synthesized and tested.
3‐(3,5‐Dimethyl‐4‐octadecanoylpyrrol‐2‐yl)propionic Acids as Inhibitors of 85 kDa Cytosolic Phospholipase A2
Authors: Lehr Matthias 
Published: October 2006

Abstract3‐(1,4‐Diacylpyrrol‐2‐yl)propionic acids were designed as inhibitors of cytosolic phospholipase A2. Enzyme inhibition was assayed by evaluation of calcium ionophore A23187‐induced arachidonic acid release from bovine platelets. While the synthesized bisacyl compound 3‐[3,5‐dimethyl‐4‐octadecanoyl‐1‐(3‐phenylpropionyl)pyrrol‐2‐yl]propionic acid was inactive at 33 μM, the related monoacylated 3‐(3,5‐dimethyl‐4‐octadecanoylpyrrol‐2‐yl)propionic acid and 3‐(1,3,5‐trimethyl‐4‐octadecanoylpyrrol‐2‐yl)propionic acid proved to be inhibitors of cytosolic phospholipase A2 (IC50: 24 μM and 13 μM, respectively).
Synthesis and Activity of the Glutathione Analogue γ‐(L‐γ‐Oxaglutamyl)‐L‐cysteinyl‐glycine
Authors: Calcagni Anna , Duprè Silvestro , Lucente Gino , Luisi Grazia , Pinnen Francesco , Rossi Domenico , Spirito Alessandra 
Published: October 2006

AbstractAn efficient synthesis of the backbone modified glutathione analogue γ‐(L‐γ‐oxaglutamyl)‐L‐cysteinyl‐glycine (7), characterized by the presence of an urethane O‐CO‐NH linkage replacing the γ‐glutamylic CH2CO‐NH fragment is described. The new analogue has been fully characterized by 1H‐ and 13C‐NMR, and FAB‐MS. Compound 7 was tested for inhibition of γ‐glutamyl‐transferase activity and was found to be a non‐competitive inhibitor of hog kidney γ‐glutamyltransferase (EC 2.3.2.2).
Effect of Guaiazulene on Some Cytochrome P450 Activities. Implication in the Metabolic Activation and Hepatotoxicity of Paracetamol
Authors: Kourounakis Angeliki P. , Rekka Eleni A. , Kourounakis Panos N. 
Published: October 2006

AbstractThe in vitro and in vivo effect of guaiazulene, a natural azulene derivative, on rat hepatic cytochrome P450 (CYP) is investigated. Furthermore, paracetamol hepatotoxicity is induced in rats and the activity of specific cytochrome P450 forms, involved in the metabolic activation of paracetamol to the toxic metabolite N‐acetyl‐p‐benzoquinone imine (NAPQI) is examined, after the administration of guaiazulene, using diagnostic cytochrome P450 substrates. It is found that guaiazulene inhibited considerably CYP1A2 and CYP2B1 and had a weak effect on CYP1A1 in rat hepatic microsomal fractions. Guaiazulene administered to rats did not produce any macroscopic toxic effect and caused no change of liver weight, microsomal protein and total cytochrome P450 content. Guaiazulene inhibited CYP1A2 activity in rats with or without paracetamol intoxication. Considering that CYP1A2 participates in the formation of NAPQI, as well as in the metabolic activation of several toxic and carcinogenic compounds, these results, in combination with the antioxidant activity of guaiazulene that we have found in previous investigations, indicate potential useful applications of guaiazulene.
Carbohydrate Natural Products as a Scaffolding for the Preparation of Potential Neuraminidase Inhibitors
Authors: Maione Anna M. , Giordani Emma , Costa Mara , Spirito Alessandra 
Published: October 2006

AbstractCompound 10b, 6‐acetamido‐6,8‐dideoxy‐D‐erythro‐β‐D‐galacto‐octopyranosyl‐1‐oxyacetic acid sodium salt, was synthesised by hydrazinolysis of Lincomycin, acetylation of methylthiolincosaminide (MTL) 9a, and by subsequent glycosylation of acetate 9b with methyl glycolate under mild conditions (NIS/TfOH). The methyl ester 10a was hydrolysed by treatment with Amberlite Ira‐4OO (OH−) resin and aqueous sodium hydroxide, followed by neutralisation with Dowex‐50 W × 8 (H+) resin and lyophilisation to give 10b. This carboxylate may represent the first derivative in a novel series of sialidase inhibitors utilising carbohydrate natural products. The phosphonate 11c, prepared under the same experimental conditions with dibenzyl(hydroxy‐methyl) phosphonate as acceptor, also displays an inhibitory activity towards Clostridium perfringens sialidase (Ki in mM range as with Neu5Ac).
Synthesis and Biological Evaluation of a Series of Quinazoline‐2‐carboxylic Acids and Quinazoline‐2,4‐diones as Glycine‐NMDA Antagonists: A Pharmacophore Model Based Approach
Authors: Colotta Vittoria , Catarzi Daniela , Varano Flavia , Cecchi Lucia , Filacchioni Guido , Galli Alessandro , Costagli Chiara 
Published: October 2006

AbstractThe synthesis and glycine‐NMDA binding activity of a series of quinazoline‐2‐carboxylic acids 1 and quinazoline‐2,4‐diones 2, containing all the essential and optional pharmacophoric descriptors required by a putative glycine antagonist model, are reported. The binding results show that only three of the title compounds displayed micromolar receptor affinity, demonstrating how disappointing the synthesis of receptor ligands based only on interaction models can be.
Microsomal Catalyzed N‐Hydroxylation of Guanfacine and Reduction of N‐Hydroxyguanfacine
Authors: Clement Bernd , Demesmaeker Mark 
Published: October 2006

AbstractGuanfacine 1 is a well known centrally acting α2‐adrenoceptor agonist with antihypertensive activity. The drug belongs to the guanidine class of compounds. The N‐oxidative biotransformation of guanfacine was investigated in vitro in the presence of hepatic microsomal fractions from rabbits, pigs, and humans. The N‐hydroxylated derivative N‐hydroxyguanfacine 2 had to be synthesized as reference for the identification of the metabolite. The corresponding in vitro retroreduction of N‐hydroxyguanfacine 2 was also investigated using the same set of enzyme sources. A new HPLC analytical method was developed in order to isolate and quantify the metabolites. A complete metabolic cycle involving the oxidative metabolism of guanfacine could only be observed in the presence of microsomal fractions from rabbit livers, whereas enzyme sources of all species under investigation catalyzed the N‐reduction of N‐hydroxyguanfacine 2.
Synthesis and Structure Elucidation of 5‐Aminomethinimino‐3‐methyl‐4‐isoxazolecarboxylic Acid Phenylamides and Their Immunological Activity
Authors: Ryng Stanislw , Machón Zdzislw , Wieczorek Zbigniew , Zimecki Michal , Glowiak Tadeusz 
Published: October 2006

AbstractA series of 5‐aminomethinimino‐3‐methyl‐4‐isoxazolecarboxylic acid phenylamides 4 has been prepared by condensation of 5‐amino‐3‐methyl‐4‐isoxazolecarboxylic acid phenylamides 1 with trichloroacetic aldehyde. Alcoholysis of trichloro derivatives 2 gave 5‐alkoxymethine derivatives 3 which, on reaction with an appropriate amine, formed the corresponding compounds 4. The compounds obtained were evaluated for their immunological activity. The properties of three compounds, described in this report, permitted inhibition of the immune response in all possible ways: diminishing both types of immune response (4d), humoral immune response (4a), or cellular immune response (4c). Preparation 4d is comparable in its effectiveness to CsA, so it may be potentially used as an agent for prolongation of the function of transplanted organs. Two other compounds may potentially be used in cases where only one type the immune response is required for combating pathogen invasion.
Naturwissenschaft und Religion in den Niederlanden um 1600
Authors: Snelders Harry A. M. 
Published: October 2006

AbstractDutch science flourished in the late sixteenth and in the seventeenth century thanks to the immigration of cartographers, botanists, mathematicians, astronomers and the like from the Southern Netherlands after the Spanish army had captured the city of Antwerp in 1585, and thanks to the religious and the socio‐economic situation of the country. A strong impulse for practical scientific activities started from the Reformation, mainly thanks to its anti‐traditional attitude, which had an anti‐rationalistic tendency. Therefore, in the Northern Netherlands there was no ‘warfare’ between science and religion and the biblical arguments leading to Galileo's condemnation were not used.Although the growth of the exact sciences and of technology in the late sixteenth and the seventeenth centuries in Protestant cirles may be partly attributed to the expansion of trade, industry, navigation and so on, this does not explain why there was also at the same time a great interest in subjects as botany and zoology, which had no immediate economic utility. There were discussions about Copernicanism and Cartesianism. So a number of astronomers and theologians rejected the earth's movement on scientific and religious grounds, but there were also those who did not reject the Copernican system on biblical grounds. In the seventeenth century there was much discussion between science and religion in the Northern Netherlands, but that discussion was not followed by censure by the Church of the State. In the Republic there was a large amount of intellectual freedom in the study of the natural sciences, thanks to practical and ideological considerations. In the eighteenth century the seventheenth century tension between science and religion changed into a physicotheological natural science. It was believed that investigations into the workings of nature should lead to a better understanding of its Creator. So Bernard Nieuwentijt in his well‐known book:The right use of‐world views for the conviction of atheists and unbelievers(1715) intended to prove the existence of God on the basis of teleological arguments.
Wissenschaft und Reformation Die Beispiele der Universitäten Königsberg und Helmstedt
Authors: Pozzo Riccardo 
Published: October 2006

AbstractThe paper considers the development of physics‐teaching at the universities of Königsberg (founded 1544) and Helmstedt (founded 1576). The question is: How many teachers of physics professed Aristotelianism and how long? and why did most of them reject Copernicanismus? The paper suggests that Melanchthon, not only the founder of early German philosophy ‘was also the propounder of a form of, modern Aristotelianism’ which proved very valuable in mediating between theologians and philosophers on the one side and between philosophers and experimentalists on the other side.
Vernunft versus Offenbarung im Spannungsfeld von Aufklärung und Pietismus
Authors: Schenk Günter 
Published: October 2006

AbstractHow is the problem of science and theology perceived at a University foundet by representatives of the pietist Aufklärung (enlightenment)? The following paper describes three historical approaches which are suggested to answer this question. The author presents and investigates especially Georg Friedrich Meier's middle course (Mittelweg), which mediates (Vermittlung) between extremes.
Einfluß der Chemischen Industrie auf den Chemieunterricht Abriß einer historischen Entwicklung
Authors: Franik Roland 
Published: October 2006

AbstractThis historical inquiry into the enfluence with the Chemical Industriy and the chemistry education at German classical stateschools is described since the revolution of 1848. The introduction of chemistry lessons at German classical stateschools step by step is further observed between 1882 and 1901. Specially the author gives a comprehensive survey about the development after the World War II.
Wissenschaft und Krieg
Authors: Ash Mitchell G. 
Published: October 2006

AbstractThe essay suggests ways in which the general history of warfare in its military, social and cultural dimensions might be brought together with the historical discussion of science, technology and war in the modern era. The thesis is advanced that more is involved than the use of science as a mere instrument for the development of weapons technology. Rather, developments fundamental to modernity itself are at work: a loss of inhibition in interacting with nature; the industrialisation of warfare, including specialisation and professionalisation within the military; a loss of inhibition in viewing other human beings, including noncombatants, as resources for war, aided in part by the employment of scientific metaphors in the service of nationalistic ideologies; and scientists' self‐employment as resources for war efforts, accompanied by their attempts to use governments as resources for research projects that would not have been conceived, let alone funded, in peacetime. The essay concludes by outlining ways in which the following articles relate to these broader concerns.
Erinnern an die Gründung: Universitätsjubiläen, Universitätsgeschichte und die Entstehung der Jubiläumskultur in der frühen Neuzeit
Authors: Müller Winfried 
Published: October 2006

AbstractThe first part of the report pursues the development of the modern jubilee tradition. The ‘Holy Year’, introduced in 1300 by Pope Bonifaz VIII, and still being celebrated in a 25 years cycle since 1475 can be considered the root of this tradition. The Catholic monopoly of jubilees was then broken by some Protestant universities. Anniversary cycles were first performed by the universities of Tübingen (1578), Heidelberg (1587) and Wittenberg (1602) to commemorate the founding of the university by a secular sovereign. With the competition of confessions in the Reich in the background this adaption of the jubilee‐idea in the university area leads to a new religiously inspired jubilee tradition in the Protestant regional churches, which celebrated the anniversary of the Reformation regularly since 1617. To counteract the Protestant onslaught of jubilees the Roman jubilee‐year, planned for a universal church, changed in the outgoing 17th and 18th century to a historically based jubilee of the dioceses, monasteries and universities in Catholic regions. ‐ The guiding role of the universities in adopting and profaning the jubilee‐year led to an early concern with the institutions' own history.As an early example for the rich production of jubilee books the anniversary speech of Heidelberg's deputy vice chancellor, Georg Sohn, of 1587 is introduced. Hence the close relationship between university jubilees and historical exploration of institutional, personal and academic history counts as a constant in university history, as will be seen in a second part with examples from the 19th and 20th century. Especially the university jubilees of the 1960s and 1970s contributed to a duration, and in parts even to the institutionalization of the historical partial discipline of the history of the universities. Finally, a few possible negative aspects of the close relationship of university jubilees to university historiography are being discussed.
Die Apotheke als Forschungsstätte
Authors: Dilg Peter 
Published: October 2006

AbstractFrom the beginning, next to their essential function of preparing drugs pharmacies also served as educational institutions, in particular for the instruction of their own rising generation. Especially between 1750 and 1850 pharmacies in addition were engaged in scientific research. It were basically experimental‐analytic chemistry and after 1800 mainly phytochemistry which inspired numerous apothecaries to do corresponding work in their laboratories. For many of those scientifically ambitious pharmacists, however, pharmacies were merely a starting point in their professional career. More or less rapidly, they turned to other places of activity which were organizationally, socially, and intellectually of higher standards (e.g. academies or universities). There, they were better able to realize their research interests frequently roused and shaped in the pharmacies. When around 1850 chemistry as an autonomous discipline definitely was established at the universities and competition became increasingly apparent through the rising chemical industry, the former meaning and function of pharmacies as places of scientific research disappeared more and more and was completely lost about 1900.
Zytoarchitektonik und Revolution ‐ Lenins Gehirn als Raum und Objekt
Authors: Richter Jochen 
Published: October 2006

AbstractThe investigation of Lenin's brain by the German neurobiologist Oskar Vogt from Berlin and his Russian collaborators in Moscow is one of the most exciting and simultaneously oddest chapters in the history of medicine. With the bizarre claim to be able to detect the material substrate of genius it provoked as much unrealistic expectations in the public as strong criticism by the scientific community of brain researchers. The present paper deals in a brief survey with the history of collecting and measuring the brains of famous persons in general and particularly with the historical, political and social circumstances of the performed investigation of Lenin's brain. In this connection the epistemological and technical prereqisites of architectonical brain research and its means of the topographical representation of complex histo‐anatomical and physiological differences in the brain cortex are shortly discussed. The opening of Russian archives after the socio‐economic turn of the year 1991 brought up new background facts in Lenin's pathobiography; together with the sources from German archives a rather extensive reconstruction of the historical events between Lenin's death in 1924 and the final report of the Moscow Brain Research Institute (Institute Mozga) to the Politburo of the Russian Communist Party (Bolsheviki) in 1936 is possible now.
Der Natur‐Begriff des 17. Jahrhunderts und zwei seiner Inter‐pretamente: „res extensa”︁ und „intima rerum”︁
Authors: Leinkauf Thomas 
Published: October 2006

AbstractThis article aims to show the general and broad use of the concept of nature in the philosophical discourse of the 17th century ‐ and in this context it is obvious that this discourse includes both philosophy and theology. I will discuss two opposite views concerning its fundamental understanding of nature, yet will not go into elaborating differences concerning such particular concepts as, for example, space, void or motion. These views and the theoretical positions from which they emerged will here be called res extensa and intima rerum ‐ this is done in order to clarify the basic opposition: there is no interior in pure extension and there is no extension at all in that what is called the interior. My aim is to show that these two views are, in fact, not quite as incompatible and contradictory as it easily may seem at first glance. Although I will for heuristic purposes introduce the two concepts res extensa and intima rerum as complete opposites and in a wholly contrary manner, ist should become clear that there exist both influences and interactions between these two notions. Theorists introduced here as advocates of the intima rerum‐position, can, for example, be seen as having been influenced by the mechanistic, or res extensa‐position, mainly through the formally and methodologically attractive geometric and mathematical argumentation. Likewise theorists advocating a mechanistic position can be said at some points to have been led by a substantial necessity concerning the contect of their argumentation to take recourse to the concept of intima rerum, at least partly or in a modified manner.
Raumvorstellungen und Erkenntnismodelle im 18. Jahrhundert
Authors: Sandl Marcus 
Published: October 2006

AbstractSince the late 17th century, two physical concepts of space exist. Isaac Newton's theory of an immovable ‘absolute space’ made it possible to explain motion and force by the quality of material elements. Less influential was Gottfried Wilhelm Leibniz's concept of space as an ‘order of coexistence’, which focuses, contrary to Newton, on the relationship between material bodies. The author argues that both concepts not only concern physical notions, but also include general models to explain cause, effect and relation. In an analogy to Newton's ‘absolute space’, theories of natural law employ the state of nature to explain society according to the anthropological quality of human beings. Leibniz's concept, in contrast, is used to elaborate theories of complex dynamic interactions and relationships. This essay attempts to illustrate the application of Leibniz's concept with examples of 18th century natural history, demography, economic theory and Charles Bonnet's natural law.
Synthesis and Crystal Structure of Pt2Sn2Zn3, the First Ternary Compound of the Pt/Sn/Zn System.
Authors: Lux Rainer , Hillebrecht Harald 
Published: October 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cs2K2 [Pt12O8(SO4)12]: A New Oxide‐Sulfate with the Cluster Anion [Pt12O8(SO4)12]4‐.
Authors: Pley Martin , Wickleder Mathias S. 
Published: October 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
EYPHKAMEN: Ln Octahedron Triples in Ln14(C2)3I20 with Ln: La, Ce.
Authors: Mattausch Hansjuergen , Simon Arndt , Kienle Lorenz , Hoch Constantin , Zheng Chong , Kremer Reinhard K. 
Published: October 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.