Formal synthesis of ent-dysiherbaine from sulfinyl dihydropyrans by sigmatropic rearrangement and tethered aminohydroxylation

Total Synthesis of Neodysiherbaine A via 1,3-Dipolar Cycloaddition of a Chiral Nitrone Template

The total synthesis of neodysiherbaine A was achieved via 1,3-dipolar cycloaddition of a chiral nitrone template with a sugar-derived allyl alcohol in the presence of MgBr₂·OEt₂. This cycloaddition constructed the C2 and C4 asymmetric centers in a single step. Then reductive cleavage, intramolecular S_N2 reaction of the tertiary alcohol, and oxidation of the primary alcohol afforded neodysiherbaine A.

Total synthesis of (-)-dysiherbaine

The enantioselective synthesis of (-)-dysiherbaine (1) has been established with efficiency via a unique synthetic strategy involving the desymmetrization of 2-substituted glycerol to install a quaternary chiral carbon, which induces further stereochemistry in the bicyclic perhydrofuropyran through mercuriocyclization and epoxidation.

Syntheses of carbocyclic aminonucleosides and (-)-epi-4'-carbocyclic puromycin: Application of palladium(0)/indium iodide-allylations and tethered aminohydroxylations

Carbocyclic aminonucleosides and epi-4'-carbocyclic puromycin were prepared from an acylnitroso-derived hetero Diels-Alder cycloadduct. Pd(0)/InI-mediated allylations of a formyl species were used to install the 4'-hydroxymethyl group. A tethered aminohydroxylation strategy was employed to install the cis-2',3'-aminoalcohol moiety with complete regio- and diastereocontrol.

[2,3]-Sigmatropic rearrangements of 3-sulfinyl dihydropyrans: application to the syntheses of the cores of ent-dysiherbaine and deoxymalayamicin A

The [2,3]-sigmatropic rearrangement of a variety of configurationally stable diastereomeric allylic sulfinyl dihydropyrans, produced by base-promoted cyclization of sulfinyl dienols, has been studied. In some cases, the efficient transformation of these substrates into dihydropyranols required an in-depth study of reaction conditions, with the preferred protocol relying on the use of DABCO in warm toluene. This methodology has been applied to the syntheses of the cores of ent-dysiherbaine and deoxymalayamicin A by means of efficient tethered aminohydroxylations.