Enantioselective synthesis of urdamycinone B and shunt metabolite 104-2 /
This dissertation reviews our convergent approach towards the total synthesis of angucycline antibiotics urdamycinone B (4) and metabolite 104-2 (5). Our quest for these O-C-arylglycosides led to the development of a method to access 2-deoxy-P-Cnaphthylglycosides. This procedure called for a metal...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742534521&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | This dissertation reviews our convergent approach towards the total synthesis of angucycline antibiotics urdamycinone B (4) and metabolite 104-2 (5). Our quest for these O-C-arylglycosides led to the development of a method to access 2-deoxy-P-Cnaphthylglycosides. This procedure called for a metal-halogen exchange of a bromonaphthalene system, hemiketal formation by addition of a sugar lactone, and direct reduction of the crude hemiketal under acidic conditions to afford the O-Cnaphthylglycoside in excellent overall yield. Conversion to bromoquinone 3 required 4 steps and proceeded in 86% overall yield. In connection with our proposed [ ] enantioselective synthesis of urdamycinone B (4) and metabolite 104-2 (5), a preparation of optically pure diene 2 starting from (-)-quinic acid (1) was developed. The conversion of (-)-quinic acid (1) to diene 2 was accomplished in 13 steps and in 23% overall yield. The assembly of angular quinones served as models for the synthesis of various angucycline antibiotics. Through these model studies the regio- and stereoselectivity was established. Furthermore, during the course of these model studies, unique oxidations involving the use of tetrapropylammonium perruthenate and the co-oxidant N-methylmorpholine N-oxide were discovered. These interesting tranformations were subsequently utilized in the total synthesis of urdamycinone B (4) and the metabolite 104-2 (5). |
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| Item Description: | Vita. "Major Subject: Chemistry". In title, numerals are used. |
| Physical Description: | xvii, 214 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |