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Updated: Aug 15, 2026

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
Synthesis, isolation and characterisation of beta-sitosterol and beta-sitosterol oxide derivatives
Florence O McCarthy1, Jay Chopra, Alan Ford
1Department of Chemistry, School of Pharmacy, Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland. f.mccarthy@ucc.ie
Abstract:
Beta-sitosterol is the most prevalent plant cholesterol derivative (phytosterol) and can undergo similar oxidation to cholesterol, leading to beta-sitosterol oxides. The biological impact of phytosterol oxides has only been evaluated in a phytosterol blend (usually of beta-sitosterol, campesterol, stigmasterol and dihydrobrassicasterol). The lack of pure phytosterols, including beta-sitosterol, hinders the collection of significant toxicity data on the individual beta-sitosterol oxides. An efficient synthetic route to multi-gram quantities of pure beta-sitosterol is described here, together with the first syntheses and characterisation of pure beta-sitosterol oxides.
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