Persistent Link:
http://hdl.handle.net/10150/280019
Title:
From C-glycosides to fused polycyclic ethernatural products
Author:
Cox, Jason M.
Issue Date:
2002
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
A highly efficient and flexible approach to fused polycyclic ethers that couples the synthesis of C-glycosides with enol ether-olefin ring closing metathesis (RCM) and/or acid mediated cyclizations has been presented. We have developed a single flask, enol ether oxidation, carbon-carbon bond forming approach to the generation of C-glycosides. We have been successful in the formation of both alpha- (Table 1.11) and beta- (Table 1.10) C-glycosides from a single glycosyl donor (glycal anhydride). Both Schrock's Mo catalyst 123 and the 2nd generation Grubbs' Ru catalyst 124 have been used in enol ether-olefin RCM reactions to generate alpha-substituted enol ethers. PPTS, pyridine, and heat have been effective in generating alpha-unsubstituted enol ethers. Our ability to couple the formation of C-glycosides with RCM or acid mediated cyclizations directed our attention to the use of this strategy in the synthesis of fused polycyclic ether natural products. We initially targeted the synthesis of hemibrevetoxin B (2). We have completed a formal total synthesis of ±-hemibrevetoxin B to Mori intermediate 167 in 21 overall steps and in 3.9% yield from the Danishefsky-Kitahara diene 74. Our success in the formal total synthesis of hemibrevetoxin B gave us great confidence to pursue the synthesis of gambierol 6. We have synthesized the A-D ring system 283 in 20 steps and in 4.2% overall yield. The FG ring system 302 was synthesized in 9 steps and in 13% overall yield. We have been successful in the generation of C-glycosides and have been able to apply them in the formation of fused polycyclic ether natural products.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Chemistry, Organic.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Chemistry
Degree Grantor:
University of Arizona
Advisor:
Rainier, Jon D.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleFrom C-glycosides to fused polycyclic ethernatural productsen_US
dc.creatorCox, Jason M.en_US
dc.contributor.authorCox, Jason M.en_US
dc.date.issued2002en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractA highly efficient and flexible approach to fused polycyclic ethers that couples the synthesis of C-glycosides with enol ether-olefin ring closing metathesis (RCM) and/or acid mediated cyclizations has been presented. We have developed a single flask, enol ether oxidation, carbon-carbon bond forming approach to the generation of C-glycosides. We have been successful in the formation of both alpha- (Table 1.11) and beta- (Table 1.10) C-glycosides from a single glycosyl donor (glycal anhydride). Both Schrock's Mo catalyst 123 and the 2nd generation Grubbs' Ru catalyst 124 have been used in enol ether-olefin RCM reactions to generate alpha-substituted enol ethers. PPTS, pyridine, and heat have been effective in generating alpha-unsubstituted enol ethers. Our ability to couple the formation of C-glycosides with RCM or acid mediated cyclizations directed our attention to the use of this strategy in the synthesis of fused polycyclic ether natural products. We initially targeted the synthesis of hemibrevetoxin B (2). We have completed a formal total synthesis of ±-hemibrevetoxin B to Mori intermediate 167 in 21 overall steps and in 3.9% yield from the Danishefsky-Kitahara diene 74. Our success in the formal total synthesis of hemibrevetoxin B gave us great confidence to pursue the synthesis of gambierol 6. We have synthesized the A-D ring system 283 in 20 steps and in 4.2% overall yield. The FG ring system 302 was synthesized in 9 steps and in 13% overall yield. We have been successful in the generation of C-glycosides and have been able to apply them in the formation of fused polycyclic ether natural products.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectChemistry, Organic.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRainier, Jon D.en_US
dc.identifier.proquest3053886en_US
dc.identifier.bibrecord.b4281277xen_US
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