Studies with plant cell cultures of Tripterycium wilfordii isolation of metabolites and biotransformation studies
department or school: Science, Faculty of
department or school: Chemistry, Department of
data provider: DSpace
degree campus: UBCV
creator: Han, Kang
issued: 2009-06-04T23:19:36Z
issued: 1995
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: This thesis is concerned with the use of plant cell cultures in combination with organic synthesis to provide efficient routes for the synthesis of novel diterpene analogs of triptolide (Tl) and tripdiolide (Td), the two most active principles of the Chinese medicinal plant Tripterygium wilfordii. The present study is also devoted to providing a better understanding with regard to the biosynthesis of related diterpenes in the plant cell culture line of T. wilfordii designated as TRP4a. The initial phases of the research involved isolation and identification of diterpene metabolites from TRP4a cell cultures. Twenty nine compounds (28 diterpenes) were isolated, of which 26 (including 14 new natural products) were isolated for the first time from this cell culture line. Based on the structural relationships revealed within this series, a biosynthetic pathway from dehydroabietane to Tl and Td is proposed. The synthetic studies involved initial synthesis of isodehydroabietenolide from the readily available dehydroabietic acid and subsequent ring C functionalization to provide a series of ring C "activated" analogs such as isotriptophenolide, triptophenolide and demethyl isoneotriptophenolide. A new, efficient sequence from isodehydroabietenolide to triptophenolide was developed and a synthesis of demethyl isoneotriptophenolide was completed. The later stages of the present studies were concerned with biotransformation of the various synthetic precursors in both TRP4a whole cell systems and crude enzyme preparations (cell free extract, or CFE). Incubation of isotriptophenolide in TRP4a cell cultures produced two novel epoxy dienones, (7,8)β-epoxy-19-hydroxy-12-oxo-18(4->3)afce0-abieta-3,9(ll),13- trien-18-oic acid lactone, and (7,8)α-epoxy-19-hydroxy-12-oxo-18(4->3)aZ?eo-abieta- 3,9(1 l),13-trien-18-oic acid lactone, along with additional hydroxylated compounds. This is the first example in which a "para-alkylated" phenol is enzymatically converted to the corresponding pa…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/8785
extent: 31486908 bytes
format: application/pdf
note: STUDIES WITH PLANT CELL CULTURES OF TRIPTERYGIUM WILFORDU ISOLATION OF METABOLITES AND BIOTRANSFORMATION STUDIES by Kang Han B. Sc, Xuzhou Normal University, 1982 M. Sc , Research Institute of Chemical Processing and Utilization of Forest Products, Chinese Academy of Forestry, 1985 A THESIS SUBMITED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Department of Chemistry) We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA November 1994 © Kang Han, 1994 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. (Signature) CAAWAI^J Department of 7" The University of British Columbia Vancouver, Canada Date J*-o.^3, tfff DE-6 (2/88) ii Abstract This thesis is concerned with the use of plant cell cultures in combination with organic synthesis to provide efficient routes for the synthesis of novel diterpene analogs of triptolide (Tl) and tripdiolide (Td), the two most active principles of the Chinese medicinal plant Tripterygium wilfordii. The present study is also devoted to providing a better understanding with regard to the biosynthesis of related diterpenes in the plant cell culture line of T. wilfordii designated as TRP4a. The initial phases of the research involved isolation and identification of diterpene metabolites from TRP4a cell cultures. Twenty nine compounds (28 diterpenes) were isolated, of which 26 (including 14 new natural products) were isolated for the first time from this cell culture line. Based…
has type: Thesis/Dissertation
date issued: 1995-05
is shown at: 10.14288/1.0061612
language: eng
degree discipline: Chemistry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/8785