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dc.contributor.advisorChakraborty, Tushar Kanti
dc.contributor.authorBegum, Sabnam
dc.date.accessioned2024-01-24T05:47:53Z
dc.date.available2024-01-24T05:47:53Z
dc.date.submitted2023
dc.identifier.urihttps://etd.iisc.ac.in/handle/2005/6387
dc.description.abstractRadical cyclization strategy always gives an expedient access to complex molecular scaffolds present in many bioactive natural products. In this research work, a systematic study is undertaken to investigate the less explored endo-trig radical cyclization in activated olefin-appended epoxides using Cp2Ti(III)Cl. The radical generated by the Ti(III)-promoted reductive opening of the epoxy ring promptly underwent an endo-trig cyclization giving an access to differently 1,3-disubstituted six- and seven-membered carbocycles in good yields and diastereoselectivity enabling a successful synthesis of a naturally occurring tri-nor-guaiane sesquiterpene, (±)-isoclavukerin A. The Cp2Ti(III)Cl-mediated reductive epoxide opening and concomitant cyclization protocol was also successfully applied in the alkenoate-appended epoxide derived from D-(+)-malic acid to achieve the first stereoselective total syntheses of three fungal secondary metabolites – monoterpenoid (+)-pestalotiolactone A, meroterpenoid (-)-myrotheciumone A and an iridoid lactone (+)-scabrol A in excellent overall yields. The last part of this thesis work delineates synthetic approaches toward the total synthesis of furanobutenolide derived norcembranoid natural product, scabrolide A, a highly congested [5-6-7] carbocyclic scaffold with six stereocenters, from a preassembled bicyclic lactone having the requisite stereocentres derived from (S)-malic acid using the Cp2Ti(III)Cl-mediated reductive epoxide opening and concomitant cyclization protocol as a key step.en_US
dc.language.isoen_USen_US
dc.relation.ispartofseries;ET00399
dc.rightsI grant Indian Institute of Science the right to archive and to make available my thesis or dissertation in whole or in part in all forms of media, now hereafter known. I retain all proprietary rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part of this thesis or dissertationen_US
dc.subjectRadical cyclizationen_US
dc.subjectNatural productsen_US
dc.subjectTotal synthesisen_US
dc.subjectscabrolide Aen_US
dc.subject.classificationResearch Subject Categories::NATURAL SCIENCES::Chemistry::Organic chemistry::Organic synthesisen_US
dc.titleCp2Ti(III)Cl-Mediated Endo- and Exo-Radical Cyclization: Synthesis of a Tri-nor-guaiane Sesquiterpene Isoclavukerin A, Terpenoid Bicyclic Lactones and Synthetic Studies Towards the Total Synthesis of Scabrolide Aen_US
dc.typeThesisen_US
dc.degree.namePhDen_US
dc.degree.levelDoctoralen_US
dc.degree.grantorIndian Institute of Scienceen_US
dc.degree.disciplineFaculty of Scienceen_US


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