Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702342
Title: Towards the total synthesis of the asbestinins
Author: Mat Som, Ian Shah Reen
ISNI:       0000 0004 6057 4321
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2016
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Abstract:
The asbestinins were isolated as the principal diterpenes from extracts of Briareum asbestinum collected by Faulkner and co-workers in 1980. The carbon skeleton of the asbestinins is related to that of cladiellins and briarellins by migration of a methyl group from C11 to C12. To date, the asbestinins represent the most evolved subclass of 2,11-cyclised cembranoid family of natural products, featuring a tetracyclic ring system with nine contiguous stereocenters and a polycyclic fully-substituted tetrahydrofuran. Several of the asbestinin natural products demonstrate diverse bioactivities such as cytotoxicity against tumour cells, antimicrobial activity and antagonism to both histamine and acetylcholine. These compounds are particularly interesting due to their complex structures and broad range of biological activities. This thesis describes the attempted total synthesis of (±)-11-acetoxy-4-deoxyasbestinin D. Initially, large-scale preparation of the tricyclic core of the asbestinins was achieved using a samarium diiodide reductive cyclisation reaction to generate tetrahydropyranol motif, [2,3]-sigmatropic rearrangement of an oxonium ylide generated from a functionalised diazoketone and an intermolecular Diels-Alder cycloaddition reaction. The work set forth in the second part deals with the challenges encountered during installation a C12 methyl group of the asbestinins in a stereoselective manner. The final part concerns successful efforts directed towards the synthesis of the complete tetracyclic core of the asbestinins.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.702342  DOI: Not available
Keywords: QD Chemistry
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