8-oxabicyclo[3.2.1]oct-6-en-3-one as a module for the synthesis of β-alkoxy-δ-valerolactones relevant to natural products and drugs

High Regio-, Chemo-, and Stereoselectivity via Low-Temperature 4 + 3 Cycloadditions. Convergent Synthesis of Multifunctionalized Vinylmetals (M = Si, Sn) and S-Vinyl Benzenecarbothioates

“…8-Oxabicyclo[3.2.1]oct-6-en-3-ones are versatile templates in synthesis since they can be elaborated into substituted tetrahydropyrans and other useful derivatives that constitute important subunits in many bioactive natural products. We have presented applications of this concept targeting prominent polyoxygenated natural products such as lasonolide A, phorboxazoles, discodermolide,2b spongistatin, dictyoxetanes, mevinic acids, and bryostatin . Other recent efforts have been concerned with the synthesis of the phorbol skeleton, polypropionate segments, and highly functionalized 5-8-5 ring systems .…”

Enantioselective alkylative double ring-opening of epoxides derived from cyclic allylic ethers: synthesis of enantioenriched unsaturated diolsElectronic supplementary information (ESI) available: the preparation and characterisation of derivatives for ee determinations. See http://www.rsc.org/suppdata/ob/b2/b212404a/

“…(Scheme 6). 33 In contrast to 40, diastereomeric ethers 41 and 43 were readily prepared via known, highly stereoselective reductions of the ketone functionality in 37, 34 followed by protection and epoxidation.…”

“…A mixture of endo-8-oxabicyclo[3.2.1]oct-6-en-3-ol 34 (1.15 g, 9.12 mmol), TBDMSCl (1.72 g, 11.4 mmol, 1.25 equiv.) and imidazole (1.55 g, 22.8 mmol, 2.5 equiv.)…”

Spongistatins: Biological activity and synthetic studies

“…Protecting groups' interconversion followed by reduction of the ester moiety and protection of the resulting aldehyde gave dithiane 308 as a C(38)e C(45) F-ring fragment. The group of Hoffmann has proposed the elaboration of 8-oxabicyclo[3.2.1]oct-6-en-3-one derivatives into functionalized tetrahydropyrans, in particular in several fragments related to spongistatins [40]. Bicyclic ketone 309 was reduced with complete selectivity to the corresponding endo-alcohol (Fig.…”