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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
561

Synthetic studies on the carpaine alkaloids

Mayne, P. M. January 1987 (has links)
This thesis describes synthetic work directed towards the synthesis of the piperidine alkaloids carpamic (1) and pseudocarpamic (100) acids. The introductory chapter reviews the occurrence, structural determination, pharmacological properties and biosynthesis of 2,3,6-trisubstituted piperidines and discusses previous synthetic work. In Chapter Two a synthetic strategy <i>via</i> the 2-azabicyclo [2.2.2]octan-5-ones (156) and (157) is proposed and the use of the imino-Diels-Alder reaction to produce these compounds is described. Chapter Three details the reactions used to convert the ester functionality in (156) and (157) into the methyl group present at C-2 in (100) and (1). In the first section transformations of the bicyclic systems are described. The second section describes the intramolecular Michael reaction of enones (183) and (184), formed as by-products in the imino-Diels-Alder reaction described in Chapter Two, to the ethylene acetals (200) and (204). In the third section unsuccessful attempts to open the bicyclic systems by double Baeyer-Villiger oxidation of dimethyl (217) and diethyl (223) acetals are described. The fourth section contains an NBS-induced rearrangement of benzylidene acetal (160) to benzoate (228) and further transformations of (228) to give (241), which has the required C-2 methyl substituent. Chapter Four describes Baeyer-Villiger oxidations of 2-azabicyclo[2.2.2]octan-5-ones and discusses the factors which may influence the relative proportions of bridgehead and methylene-migrated lactones. In Chapter Five the carpamic and pseudocarpamic acid C-6 side-chains are introduced <i>via</i> Wittig reactions on aldehydes (293) and (284) and methyl N-tosylcarpamate (295) and methyl N-tosylpseudocarpamate (291) are prepared.
562

Polyketide biosynthesis

Abell, C. January 1982 (has links)
No description available.
563

Mixed-metal organometallic clusters

Jackson, Patricia A. January 1988 (has links)
No description available.
564

Studies on benzenoid natural products

James, K. January 1980 (has links)
No description available.
565

The regio- and stereocontrolled synthesis of allylsilanes

Thomas, A. P. January 1986 (has links)
No description available.
566

The chemistry of ligand-bridged homodinuclear and heterodinuclear complexes

Horton, A. D. January 1985 (has links)
No description available.
567

Synthetic studies on aplysistatin and mucohalic derivatives

Demnitz, F. W. J. January 1983 (has links)
No description available.
568

Synthesis of spirocyclic compounds via organoiron complexes

Perrior, T. January 1983 (has links)
No description available.
569

Synthesis and chemistry of hexaosmium carbonyl 'raft' clusters

Jeffrey, J. G. January 1985 (has links)
No description available.
570

The synthesis of cis- and trans-maneonenes

Kendrick, D. A. January 1984 (has links)
No description available.

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