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Filtering by: Creator Schmidt%2C Mariek E. Remove constraint Creator: Schmidt%2C Mariek E. Advisor White, James D. Remove constraint Advisor: White, James D.

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  • Absolute stereochemistry and total synthesis of botryococcene

    Creator:
    Reddy, Guvvala Nagabhushana
    Abstract:
    Studies were carried out to determine the absolute stereochemistry of botryococcene (1). The natural product was degraded to two sets of 'y- and 8- valerolactones. All enantiomeric variations of these lactones were synthesized in optically pure form starting from (S)- and (R)-methyloxiranes. 1H NMR correlation of natural and synthetic materials...
    Resource Type:
    Dissertation
    Full Text:
    -[(methoxymethypoxy]-3-E-hexenoate (126 and 127), and an organocopper coupling reaction. Methyl (2S)-3-hydroxy-2

  • Chiral synthesis of monic acid C

    Creator:
    Theramongkol, Parinya
    Abstract:
    Bromoalkoxylation of dihydropyran with bromine and 1-borneol, followed by dehydrobromination and epoxidation, afforded trans-2-1- bornyloxy-3,4-epoxytetrahydropyran as a major product. This was treated with sodium phenylselenide to give a 1:1 mixture of (2R,3R,4R)- 2-1-bornyloxy-3-hydroxy-4-phenylselenotetrahydropyran and its (2S,3S, 4S) diastereomer. Elimination of the selenoxide, derived from oxidation of the former with hydrogen...
    Resource Type:
    Dissertation
    Full Text:
    desired E-butenoate as the major product. Selec- tive reduction of the methyl ester of these diesters

  • Synthetic studies on the macrolide antibiotic rutamycin B

    Creator:
    Wang, Shan
    Resource Type:
    Dissertation
    Full Text:
    37 E Ale > Me°2C OH Y OR OR 65 57 Y = 0; 58 Y = NNMe2 EA,/' I I' A/> > - CO2Me OR

  • Intramolecular diels-alder cycloadditions of citraconic and mesaconic esters ; Studies on the synthesis of the northwest and southeast segments of boromycin

    Creator:
    Sheldon, Bernard Gale
    Resource Type:
    Dissertation
    Full Text:
    (3 H, s), 1.9 (3 H, s), 1.7 (3 H, d, J = 6 Hz); MS m/e 180.116 (M+, calc for C 11 H 16 0 2 180.115

  • Studies toward the total synthesis of (+)-providencin

    Creator:
    Jana, Somnath
    Abstract:
    Studies toward the total synthesis of (+)-providencin (1), a highly oxygenated cembranoid dipterpene with a unique bicyclo[12.2.0]hexadecane skeleton and pronounced biological activity, are described. These studies resulted in the synthesis of advanced intermediates 320 and 332 which contain all of the carbon atoms of 1. In a first generation approach...
    Resource Type:
    Dissertation
    Full Text:
    3.4 Installation of an (E)-trisubstituted alkene at C7-C8 of providencin………………………………………….… 45

  • 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:
    enzyme present in vivo, converts the (R) e n anti o me r of 6 to the active (S)-enantiomer.4 / NH 0 0

  • 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:
    ) Phorboxazole A.. 2 151 153 235 LIST OF TABLES Table Page 2.1 E/Z Isomerization

  • Total synthesis of indole alkaloids: pt. 1. Asymmetric synthesis of (-)-ibogamine. pt. 2. An approach toward the synthesis of koumine

    Creator:
    Choi, Younggi
    Abstract:
    PART I. The preparation of (-)-ibogamine (1) in fourteen steps from benzoquinone and in 10% overall yield is a powerful illustration of the value of the asymmetric Diels-Alder reaction as a starting point in a multistep synthesis. All four cycloadducts, 70, 77, 84 and 96, obtained with the (S)-BINOL-TiCl₂ complex...
    Resource Type:
    Dissertation
    Full Text:
    , Paul R. Blakemore, Cindy Browder, Rich G. Carter, Bobby Chow, Jorg Deerberg, Nicholas E. Drapela, Uwe

  • Approaches to the synthesis of penicillin

    Creator:
    Furuta, Takuya
    Abstract:
    Several approaches to the synthesis of penicillin from 2-iminothioazolidine 50, from 2-thiothiazolidine 66 and by photocyclization of 77 and 78 were investigated. 2-Iminothiazolidine 50 was prepared from dibromoester 45 by the action of benzylamine followed by treatment of aziridine 46 with potassium or ammonium thiocyanate. Attempted introduction of a two-carbon...
    Resource Type:
    Dissertation
    Full Text:
    21 E- NO2 C H4 CH= 21 + 22 N3 CH2 COC1 COOCH2 Ph E- NO 2C 6 H 4 CHO Et 3N e0OCH 2Ph 1 PhLi

  • Studies toward the total synthesis of phorboxazole A

    Creator:
    Kuntiyong, Punlop
    Abstract:
    Studies toward the total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, were conducted and resulted in a route to an advanced intermediate, C4-C32, for this purpose. A key feature of our approach is the stereoselective synthesis of two cis-2,6-disubstituted tetrahydropyrans present in the macrolide portion of...
    Resource Type:
    Dissertation
    Full Text:
    , M. D.; Doubek, D. L.; Boyd, M. R.; Schmidt, J. M.; Chapuis, J-C.; Hamel, E.; Bai, R.; Hooper, J. N