Synthesis of hemigossypol.
| Main Author: | |
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
[College Station, Tex.] :
Hottman,
1979.
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| Subjects: | |
| Online Access: | Link to ProQuest copy Link to OAKTrust copy |
| Abstract: | Inoculation of cotton plants (Gossypium spp.) with strains of the fungus Verticillium causes an increased production of secondary metabolites, such as hemigossypol (HG) and related sesquiterpenoids. These sesquiterpenoids are fungistatic and/or fungi toxic and as such are classified as phytoalexins. Invasion of the host by the pathogen induces the host to produce phytoalexins that disrupt normal pathogen development. In order to study the mechanisms of host infection responses, these sesquiterpenoids must be available in sufficient quantities for biological activity tests. Since these compounds are produced in small quantities and are difficult to purify, a synthetic study of these compounds was undertaken. The target molecule of this study was hemigossypol (HG). The starting material for the synthesis of hemigossypol (HG) was 3 -isopropyl catechol (23). With the phenol groups protected as methyl ethers, this compound was selectively formylated by a chloromethylationoxidation sequence. The B ring was introduced by a Stobbe condensation, followed by cyclization of the saturated Stobbe product with polyphosphoric acid. Aromatization of the B ring followed by reduction of the ester group produced the apohemigossypol dimethyl ether 48. The B ring was deactivated by esterifying the phenol to an acetate. Selective formylation and demethylation yielded hemigossypol (HG). ... |
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| Item Description: | "Major subject: Chemistry." Vita. |
| Physical Description: | x, 91 leaves ; 28 cm |
| Bibliography: | Includes bibliographical references (leaves 87-90). |