A Stereoselective Synthesis of Fused Carbocycles with a cis-1,2-Diol Moiety by Desymmetrization: SmI-Mediated Pinacol Coupling of meso-Cyclic 1,3-Diones.

Samarium diiodide (SmI)-mediated desymmetrization of a meso-cyclic 1,3-dione pinacol coupling is described. The reaction proceeds with high stereoselectivity to provide fused carbocyclic compounds with three contiguous stereogenic centers featuring an all-carbon quaternary center and a cis-1,2-diol moiety.

Total Synthesis of Thuggacin cmc-A and Its Structure Determination.

The first total synthesis of thuggacin cmc-A and the determination of the absolute structure are described. The thuggacin family of antibiotics is of great interest due to the antibiotic activity against . Based on the assumption that seven stereogenic centers in thuggacin cmc-A would share the same stereochemistry as thuggacin-A, all stereogenic centers of thuggacin cmc-A were strictly constructed in a stereocontrolled manner.

Synthetic studies toward longeracemine: a SmI-mediated spirocyclization and rearrangement cascade to construct the 2-azabicyclo[2.2.1]heptane framework.

Longeracemine, a member of the family of alkaloids contains a novel carbon framework featuring a highly functionalized 2-azabicyclo[2.2.1]heptane core as part of an overall 5/6/5/5/6/5 skeleton.

Formal Synthesis of (-)-Haliclonin A: Stereoselective Construction of an Azabicyclo[3.3.1]nonane Ring System by a Tandem Radical Reaction.

A formal synthesis of (-)-haliclonin A, isolated from the marine sponge sp. in Korea, is described. The key feature of the synthesis includes the highly stereoselective tandem radical reaction to construct the azabicyclo[3.

Catalytic Asymmetric Total Synthesis of Exiguolide.

The catalytic asymmetric total synthesis of (-)-exiguolide, a complex 20-membered macrolide embedded with a bis(tetrahydropyran) motif, is reported. The convergent synthesis involves the construction of the C1-C11 tetrahydropyran segment via catalytic asymmetric allylation and Prins cyclization, and the formation of the C12-C21 phosphonate segment via catalytic asymmetric cyclocondensation reaction and Johnson-Claisen rearrangement. The synthesis of 15-epi-exiguolide is also described.

New entry to the enantioselective formation of substituted cyclohexenes bearing an all-carbon quaternary stereogenic center.

Enantioselective formation of cyclohexene derivatives bearing an all-carbon quaternary stereogenic center is described. The racemic cyclohexenes are readily transformed to chiral substituted cyclohexenes in good yield with excellent enantioselectivity and diastereoselectivity by a palladium-mediated deracemization. The resulting products are promising synthetic intermediates of biologically active natural products.

Total Synthesis of Lajollamycin B.

The first total synthesis of lajollamycin B, a structurally novel nitro-tetraene spiro-β-lactone/γ-lactone antibiotic, is described. The convergent synthesis involves the construction of the C8'-C11' nitrodienylstannane and its coupling with the segment prepared from the C1'-C7' ω-iodoheptadienoic acid and the right-hand heterocyclic fragment, which has been utilized for our previous syntheses of oxazolomycin A. The revision of the geometry of the terminal Δ -double bond from E to Z is also described for the structure of natural lajollamycin B.

Total Synthesis of (-)-N-Methylwelwitindolinone C Isothiocyanate Based on a Pd-Catalyzed Tandem Enolate Coupling Strategy.

The highly stereocontrolled total synthesis of (-)-N-methylwelwitindolinone C isothiocyanate is described, which features the expeditious construction of a bicyclo[4.3.1]decane ring system by a palladium-catalyzed tandem enolate allylation/arylation reaction.

Stereocontrolled total synthesis of (-)-englerin A.

The total synthesis of (-)-englerin A, a potent and selective inhibitor of renal cancer cell lines, is described. The key feature includes the stereocontrolled construction of the cyclopentane structure by taking advantage of a base-promoted epoxynitrile cyclization.