Bridging Analogies Research Articles

Synthesis and characterization of cobalt cyclidene complexes with long polymethylene bridges and their binding to small molecules

The synthesis of four novel cobalt(II) cyclidene complexes with long polymethylene bridges is described. These complexes have been found to reversibly bind dioxygen in a manner similar to that of their shorter bridged analogs. Dioxygen affinities are reduced for bridge lengths exceeding that of octamethylene, an effects on small-molecule binding that are associated with the long bridge have been examined by comparison of the X-ray crystal structure of th undecamethylene-bridged cobalt(III) complex with the shorter bridged analogues.

The photochemistry of a two-carbon ortho-ortho phenyl-bridged 4,4-diphenyl-2-cyclohexen-1-one

The synthesis and photochemistry of 10′,11′-dihydrospiro[2-cyclohexene-1,5′-[5H]-dibenzo[ a,d]cyclohepten]-4-one ( 9) are described. The irradiation of 9 resulted in the formation of four photoproducts, three resulting from aryl migration and the fourth deriving from an incomplete type A mechanism. These were identified as the six-ring α,β-enone system 10, the cis- and trans-diphenyl tricyclic systems 11 and 12 and the five-ring β,γ-enone 13. A significant solvent effect on product ratios was observed on irradiation of 9 in tert-butyl alcohol, benzene and cyclohexane. While the α,β-enone 10 was kinetically preferred in tert-butyl alcohol, irradiation in benzene and cyclohexane led preferentially to the trans-diphenyl product 12. The α,β-enone was the photodynamic product in all solvents. Control irradiations suggested that all four photoproducts result from both primary and secondary photoreactions. Mechanisms for both the primary and secondary reactions are discussed. Finally, comparisons are made with the photochemistry of the zero- and three-carbon bridged analogs 4a and 4b, as well as the parent system 4,4-diphenyl-2-cyclohexen-1-one ( 1).

An Analogy‐Based Computer Tutor for Remediating Physics Misconceptions

Abstract We describe a computer tutor designed to help students understand physics concepts. The tutor uses a teaching strategy called “bridging analogies” that previous research has demonstrated to be successful in one‐on‐one tutoring. The strategy is designed to remedy misconceptions by appealing to existing correct intuitions, and extending these intuitions by encouraging analogical thinking. Students were videotaped while using the program and were encouraged to think aloud. The strategy was successful in changing beliefs for some students. We outline suggestions for improving the tutor using artificial intelligence technology.

Studies on conformationally restricted, disiloxane bridged analogues of the enkephalins

Solution-phase synthesis of protected [Ser2, Ser5]- and [D-Ser2, Ser5]-enkephalins, followed by treatment with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane [Pri2Si(Cl)–O–Si(Cl)Pri2] in base have yielded cyclic bridged disiloxane analogues showing biological activity in an in vitro assay. Highfield 1H n.m.r. studies augmented by n.O.e. difference spectroscopy, temperature dependence studies of the amide protons, and the use of computer graphics support the presence of a 2→5 H-bonded β-bend conformation for the most biologically potent of the cyclic analogues.

Stereochemical studies on medicinal agents. VI. Bicyclic bases. Synthesis and pharmacology of epimeric bridged analogs of meperidine, 2-methyl-5-phenyl-5-carbethoxy-2-azabicyclo[2.2.1]heptane.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStereochemical studies on medicinal agents. VI. Bicyclic bases. Synthesis and pharmacology of epimeric bridged analogs of meperidine, 2-methyl-5-carbethoxy-2-azabicyclo[2.2.1]heptanesPhilip S. Portoghese, Adel A. Mikhail, and Harvey J. KupferbergCite this: J. Med. Chem. 1968, 11, 2, 219–225Publication Date (Print):March 1, 1968Publication History Published online1 May 2002Published inissue 1 March 1968https://doi.org/10.1021/jm00308a006RIGHTS & PERMISSIONSArticle Views96Altmetric-Citations23LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (952 KB) Get e-Alerts Get e-Alerts