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Filtering by: Creator Hathaway, D. O. Remove constraint Creator: Hathaway, D. O. Academic Affiliation Chemistry Remove constraint Academic Affiliation: Chemistry Advisor White, James D. Remove constraint Advisor: White, James D.

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  • Synthetic studies of nonadrides

    Creator:
    Drapela, Nicholas Ernest
    Abstract:
    An asymmetric approach to the synthesis of byssochlamic acid (1) is described. Regioisomeric enzymatic differentiation is described in the selective hydrolysis of dimethyl ester 30 by porcine liver esterase. Chiral dimethyl ester 42 was prepared by desymmetrization of cyclopentene 34 using porcine liver esterase. A key intramolecular [2+2]cycloaddition-cycloreversion photometathesis of...
    Resource Type:
    Dissertation
    Full Text:
    14 1998. Title: Synthetic Studies of Nonadrides Abstract approved: James D. White An asymmetric

  • Total synthesis of (-)-7-epicylindrospermopsin

    Creator:
    Hansen, Joshua D.
    Abstract:
    The first asymmetric synthesis of (-)-7-epicylindrospermopsin via intramolecular nitrone cycloaddition is described. The synthesis utilized a convergent approach to prepare the cycloaddition precursor 176, which was assembled by condensation of hydroxylamine 175 with aldehyde 145. Hydroxylamine 175 was synthesized from ethylene glycol (166) in seven steps. Aldehyde 145 was completed...
    Resource Type:
    Dissertation
    Full Text:
    OF THE DISSERTATION OF Joshua D. Hansen for the degree of Doctor of Philosophy in Chemistry

  • Total synthesis of phorboxazole A

    Creator:
    Lee, Tae Hee
    Abstract:
    The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A. The synthesis used a convergent approach involving...
    Resource Type:
    Dissertation
    Full Text:
    , 3801. (n) Greer, P. B.; Donaldson, W. A. Tetrahedron 2002, 58, 6009. (o) White, J. D.; Kranemann, C. L

  • Studies toward the total synthesis of sanglifehrin A

    Creator:
    Suttisintong, Khomson
    Abstract:
    Studies toward synthesis of subunits of sanglifehrin A, an immunosuppressant featuring a highly substituted [5,5]-spirolactam moiety as well as a 22-membered macrocycle are described. The macrolactone contains a peptidic backbone characterized by an unusual [beta]-substituted (S)-piperazic acid and (S)-m-hydroxyphenylalanine units. These studies resulted in the synthesis of advanced intermediate 358...
    Resource Type:
    Dissertation
    Full Text:
    65 Sanglifehrin B (2) Sanglifehrin C (3) Sanglifehrin D (4) 15 O NH O 33 36 38 40 42 43 45

  • Synthetic studies on marine natural products : Part 1. Synthesis of the sesquiterpenoid dihydropallescensin D via manganese(III)- mediated carbocyclization. Part 2. Approaches toward the synthesis of prianosin and discorhabdin alkaloids

    Creator:
    Yager, Kraig M.
    Resource Type:
    Dissertation
    Full Text:
    compounds. 0, So d Na. H 0 O 0 Aplasmomycin A (1) OH H2N H2N NH + NH2 NH OH OH Saxitoxin (2

  • Studies towards the total synthesis of (-)-kendomycin

    Creator:
    Smits, Helmars
    Abstract:
    Studies towards the total synthesis of (−)-kendomycin (1), a bacterial metabolite with a unique molecular architecture and pronounced biological activity, are described. These studies resulted in the synthesis of advanced intermediate 208, containing all of the carbon atoms of 1. A Dötz annulation between alkyne 122 and novel chromium carbenoid...
    Resource Type:
    Dissertation
    Full Text:
    :_____________________________________________________ James D. White Studies towards the total synthesis of (−)-kendomycin (1), a bacterial

  • Tandem intramolecular photocycloaddition-retro-Mannich fragmentation as a route to indole and oxindole

    Creator:
    Li, Yang
    Abstract:
    Irradiation of a tryptamine linked through its side-chain nitrogen to an alkylidene malonate residue results in an intramolecular [2 + 2] cycloaddition to the indole 2,3-double bond. The resultant cyclobutane undergoes spontaneous retro-Mannich fission to produce a spiro[indoline-3,3-pyrrolenine] with relative configuration defined by the orientation of substituents in the transient...
    Resource Type:
    Dissertation
    Full Text:
    approved: James D. White

  • Cis-2,5-diaminobicyclo[2.2.2]octane : a novel C₂-symmetric scaffold for asymmetric catalysis

    Creator:
    Shaw, Subrata
    Abstract:
    This thesis describes the development of a new enantioselective synthetic method employing chiral cis-2,5-diaminobicyclo[2.2.2]octane-based organometallic catalysts. The significance of this new method to organic synthesis is illustrated with preparation of enantioenriched products that are transformed to important pharmaceutical agents. Chapter 1 provides a brief historical overview of asymmetric catalysis, especially...
    Resource Type:
    Dissertation
    Full Text:
    [2.2.2]octane: A Novel C2-Symmetric Scaffold for Asymmetric Catalysis Abstract approved: James D

  • Synthesis of epothilones and epothilone analogues

    Creator:
    Sundermann, Kurt F.
    Abstract:
    A convergent synthesis of epothilone B that generates all seven of its asymmetric centers in a completely stereoselective fashion has been completed. Key reactions include an anti-Felkin aldol condensation to set the C6 and C7 stereochemistry, a directed α-hydroxylation to install the C15 (S)-hydroxyl substituent, and a Wittig condensation to...
    Resource Type:
    Dissertation
    Full Text:
    epothilone B, epothilone D, and paclitaxel showed that the synthetic analogues were less potent than their

  • Studies towards the total synthesis of (-)-gymnodimine

    Creator:
    Wang, Guoqiang
    Abstract:
    Studies towards the total synthesis of (-)-gymnodimine (1), a marine neurotoxin with a unique molecular architecture and pronounced biological activity, are described. These studies resulted in a convergent approach to the advanced intermediate 315, containing the C3-C32 section of 1. Two synthetic routes were developed to construct the tetrahydrofuran subunit...
    Resource Type:
    Dissertation
    Full Text:
    Total Synthesis of ()-Gvmnodimine Abstract James D. White Studies towards the total synthesis of