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Filtering by: Creator O'Conner, Carl W. Remove constraint Creator: O'Conner, Carl W. Academic Affiliation Chemistry Remove constraint Academic Affiliation: Chemistry Advisor White, James D. Remove constraint Advisor: White, James D.

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  • Approaches toward the asymmetric synthesis of pillaromycin A

    Creator:
    Nolen, Ernest G.
    Resource Type:
    Dissertation
    Full Text:
    required formation of an o-toluate anion 20, a Michael reaction of this anion with a cyclohexenone

  • Studies on the synthesis of the "northern" and "southern" segments of boromycin and aplasmomycin

    Creator:
    Kang, Myung Chol
    Abstract:
    The stereocontrolled synthesis of the southern lactone 17 of boromycin and of the northern segments of both boromycin and aplasmomycin are described. The syntheses begin with enantioselective epoxidation of 3-buten-2-ol (42) to provide the optically active 2(S),3(R) epoxy alcohol 43. The absolute configuration was confirmed by preparing 43 from (-)-2,3-dihydroxybutyric...
    Resource Type:
    Dissertation
    Full Text:
    synthesized from 43. Segments 61 and 39, corresponding to the southeast quadrant of boromycin, and 100 and

  • Approaches toward synthesis of the mycosporins

    Creator:
    Cammack, Janice H.
    Abstract:
    The mycosporins, formerly called P310's are secondary metabolites of fungi closely associated with fungal reproductive processes that require light. The structurally related iminomycosporins are found in marine plants and animals and may also have functions related to light. In this study, approaches toward the asymmetric synthesis of the mycosporins are...
    Resource Type:
    Dissertation
    Full Text:
    further use. 39 COI cp _ O 49 N'/N \_-=J Ph PhSi-0 0,, 0\s OH 6_6 48 CH3OH 0 H3 50 Primary

  • Approaches to the synthesis of methymycin

    Creator:
    Raghavan, Palaykotai Rajagopalan
    Abstract:
    Several approaches to the synthesis of methymycin were investigated. Segment A (39), containing functionality corresponding to C-9, 10, and 11 of methynolide was made in six steps from propionaldehyde in an overall yield of 37%. Oxidation of 34 with silver nitrate gave 35 which, upon hydroxylation with hydrogen peroxide, gave...
    Resource Type:
    Dissertation
    Full Text:
    ., 31), suitable for coupling with the previously prepared alde- hyde 39. 84 HO 86 Br 64 o Br

  • 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:
    bicyclic core of CP-225,917 (8) and CP-263,114 (9). The strategy employs Birch reduction of o-anisaldehyde

  • 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:
    secondary hydroxyl group was protected as its triethylsilyl ether 198. O-alkylation of the urea function

  • The synthesis of trisporic acids

    Creator:
    Prisbylla, Michael Paul
    Abstract:
    A total synthesis of the fungal hormones, trisporic acids A and B, is described, starting from a -methyltetronic acid 34. A Robinson annelation of 34 with ethyl vinyl ketone affords the lactone 33. Treatment of 33 with N-bromosuccinimide gave 97, which was hydrolyzed to the lactol 103. The reaction of...
    Resource Type:
    Dissertation
    Full Text:
    appreciated. I thank Professor Stanley E. Wilson for his always optimistic outlook, and also Dr. Carl N

  • 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:
    38 Chapter 3. The Asymmetric Hetero-Diels-Alder Reaction 39 3.1 Introduction 39 3.2 Role of

  • 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

  • Total synthesis of (+)-bourgeanic acid and conformational analysis of its dilactone

    Creator:
    Johnson, Alan T. (Alan Thomas), 1957-
    Resource Type:
    Dissertation
    Full Text:
    must also thank my parents, Carl and Mary, for their support and for giving me the opportunity to