1 40 1 Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. URL Address <a href="http://doi.org/10.1016/j.molstruc.2013.04.030" target="_blank" rel="noreferrer noopener">http://doi.org/10.1016/j.molstruc.2013.04.030</a> Rights Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s). Pages 86-94 Volume 1045 Search for Full-text Locate full-text within NEOMED Library's e-journal collections <p>Users with a NEOMED Library login can search for full-text journal articles at the following url: <a href="https://libraryguides.neomed.edu/home">https://libraryguides.neomed.edu/home</a></p> Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Triquinane scaffolds: Shape and geometry as a function of saturation and bridgehead groups Publisher An entity responsible for making the resource available Journal of Molecular Structure Date A point or period of time associated with an event in the lifecycle of the resource 2013 2013-08 Subject The topic of the resource amines; blocker; Chemistry; Crystal structure; derivatives; L-type calcium channel blockers; olefin metathesis; Pentacycloundecane; Polycyclic cage; system; Triquinane Creator An entity primarily responsible for making the resource Young L M; Zeller M; Geldenhuys W J; Malan S F; Van der Schyf C J Description An account of the resource Polycyclic hydrocarbon compounds, also known as "cage compounds", are of interest in drug discovery due to their versatility as scaffolds. Derivatives of both pentacycloundecane-dione and triquinane-dione have been the focus of numerous investigations as multifunctional neuroprotective drugs where these compounds were used as novel drug scaffolds with the ability to cross the blood brain barrier. Here we present the synthesis, characterization and single crystal X-ray analysis for two triquinane synthons; tricyclo[6.3.0.0(2.6)]undecane-4,9-diene-3,11-dione (compound 5 crystallizes in the monoclinic system, unit cell parameters are: a=6.5876 (12) angstrom, b=10.4204 (19) angstrom, c=12.074 (2) angstrom; V=825.4 (3) angstrom(3) and Z=4) and tricyclo[6.3.0.0(2.6)]undecane-3,11-dione (compound 6 crystallizes in monoclinic system, unit cell parameters are: a=7.5992 (7) angstrom, b=10.7294 (10)angstrom, c=10.8664 (10) angstrom; V=884.04 (14) angstrom(3) and Z=4); as well as a triquinane derivative, N-(3-methoxybenzyl)-3,11-azatricyclo[6.3.0.0(2.6)]undecane (compound 11 crystallizes in triclinic system, unit cell parameters are: a = 7.6714 (7) angstrom, b=9.0100 (9) angstrom, c=11.2539 (11) angstrom; V=745.78 (12) angstrom(3) and Z=2). The size and geometrical conformation of the triquinane scaffolds were compared to tetra and pentacycloundecanes, revealing that tricyclo[6.3.0.0(2.6)]-undecane-3,11-dione experiences strain relief resulting in greater flexibility, a more asymmetric molecular shape and larger surface area. However, with the introduction of the aza-bridge in N-(3-methoxybenzyl)-3,11-azatricyclo[6.3.0.0(2.6)]undecane, much of the flexibility and asymmetry is lost again. We also discuss the rearrangement mechanism for the observed retro cycloaddition and reversion, and utilized density functional theory calculations to discuss the photocyclization mechanism of this unique [2 + 2] Diels-Alder system. (C) 2013 Elsevier B.V. All rights reserved. Identifier An unambiguous reference to the resource within a given context <a href="http://doi.org/10.1016/j.molstruc.2013.04.030" target="_blank" rel="noreferrer noopener">10.1016/j.molstruc.2013.04.030</a> Format The file format, physical medium, or dimensions of the resource Journal Article 2013 amines blocker Chemistry Crystal structure derivatives Geldenhuys W J Journal Article Journal of Molecular Structure L-type calcium channel blockers Malan S F olefin metathesis Pentacycloundecane Polycyclic cage system Triquinane Van der Schyf C J Young L M Zeller M