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Updated: Jun 11, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Total synthesis of (+)-cis-sylvaticin: double oxidative cyclization reactions catalyzed by osmium
Timothy J Donohoe1, Robert M Harris, Jeremy Burrows
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, UK. timothy.donohoe@chem.ox.ac.uk
Abstract:
The double oxidative cyclization of dienes is a viable procedure for making complex natural products containing cis-THF units. A double deprotection/double oxidative cyclization strategy using catalytic osmium tetroxide was used to construct the bisheterocyclic core of cis-sylvaticin and ultimately confirm its structure. The natural product was then prepared by a short sequence of reactions that is exceptionally concise: the final route being just 13 linear steps and 19 chemical operations in total.
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