In this thesis, a review concerning pentacyclic quassinoid total syntheses from 1990 to 2005 and structure activity relationship is presented. / Synthetic studies towards pentacyclic quassinoids, namely (-)-samaderine E and (-)-samaderine Y from (S)-(+)-carvone are described. Total synthesis of (-)samaderine Y was accomplished in 21 steps with 1.1% overall yield in which the synthesis was based on a C→CE→ABCE→ABCDE ring annulation sequence. The crucial points included: (1) a regioselective allylic oxidation to functionalize C ring; (2) a stereoselective epoxymethano bridge formation; (3) an intramolecular Diels-Alder reaction resulting in the construction of AB ring; (4) an intramolecular aldol reaction for the construction of D ring; (5) a regioselective allylic oxidation and an alpha-keto acetoxylation to functionalize the A ring. / Yeung Ying-yeung. / "June 2005." / Adviser: Tony K. M. Shing. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3811. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 172-178). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

by Xue You Zhu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 138-143). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.