Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484837
Title: Isotopic labelling of dietary antioxidants: Synthesis of indoles using functionalised titanium benzylidenes reagents for solid-phase
Author: Petersson, Hanna M.
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2008
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Abstract:
A route to l3C-Iabelled quercetin-3-0-D-glucoside l3C_7 was developed. Our route gives the flavonol glucoside 13C_7 with an isotopic label at C-2 in 18% yield over five steps from the point of introduction of the isotopic label. Attempts were also made to synthesise the isotopically labelled cyanidin-3-0-D-glucoside 13C_8 using methods described in the literature, but these gave low yield of the anthocyanin. A new diversity-based a route for the solid phase synthesis of N-Bn-2,S-disubstited iodoles 15 has been developed. Aniline derivative 9 was reduced using a low-valent titanium species, Cp2Ti[P(OEt)3)2 10, to give a novel titanium(IV) alkylidene reagent 11 which allq,lidenated resinbound esters 12 and gave resin-bound enol ethers 13. Suzuki cross-couplings were then performed on solid phase to introduce an aryl group at the 5 position. Treatment with mild acid (1% TFADCM) cleaved the resin bound enol ether 14 from the resin. Simultaneously Boc deprotection and cyclisation under acidic condition (10% TFA-DCM) gave N-Bn-2,S-disubstited indoles 15 in good purity and moderate yield. In a similar way using N-prenyl-N-Boc aniline 16 gave N-prenyl-2,S-disubstituted indoles 17 in good purity and moderate yield using the same solid-phase method as above. A synthetic route to the N-TMS-N-Boc aniline 18 has also been developed, which should give unprotected 2,5-disubstitued indoles 19 in high purity.
Supervisor: Not available Sponsor: Not available
Qualification Name: University of Glasgow, 2008 Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.484837  DOI: Not available
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