Synthetic approaches to I. The D-ring of oridonin, and II. The A-ring of taxol.

Title: Synthetic approaches to I. The D-ring of oridonin, and II. The A-ring of taxol.
Identifier: AAI9119690
identifier: 9119690
Creator: Wilson, Phyllis Joy.
Contributor: Adviser: William F. Berkowitz
Date: 1991
Language: English
Publisher: City University of New York.
Subject: Chemistry, Organic
Abstract: This study was directed towards the synthesis of the natural products oridonin and taxol. Methodologies for construction of the bicyclo (3.2.1) octane fragment of the C/D subunit of oridonin were investigated. Towards this end, palladium coupling reactions and free radical carbocyclization reactions were explored.;In designing a synthesis based on free radical cyclization, a major consideration is the regioselectivity of the reaction. When both 5-exo-trig and 6-endo-trig modes of cyclization are possible, five membered ring formation predominates. The results of our studies indicate equal formation of both 5 and 6 membered rings following vinyl radical carbocyclization. Factors affecting this unexpected regiochemical outcome were investigated.;The A-ring of taxol was the next synthetic target. This was approached by the electrophilic cyclization of an epoxy olefin for construction of the 6-membered ring.
Type: dissertation
Source: PQT Legacy CUNY.xlsx
degree: Ph.D.

Media: Synthetic approaches to I. The D-ring of oridonin, and II. The A-ring of taxol.