Structural basis of the antiproliferative activity of largazole, a depsipeptide inhibitor of the histone deacetylases.

Largazole is a macrocyclic depsipeptide originally isolated from the marine cyanobacterium Symploca sp., which is indigenous to the warm, blue-green waters of Key Largo, Florida (whence largazole derives its name). Largazole contains an unusual thiazoline-thiazole ring system that rigidifies its macrocyclic skeleton, and it also contains a lipophilic thioester side chain.

Biomimetic syntheses from squalene-like precursors: synthesis of ent-abudinol B and reassessment of the structure of muzitone.

We achieved the stereoselective syntheses of two different structural patterns corresponding to the enantiomers of the marine natural products abudinol B and muzitone, by developing two-directional tandem biomimetic cyclizations of polyepoxides of squalene analogues in which one alkene was functionalized as an enolsilane. In the course of this work, we demonstrated that the structure of muzitone was misassigned.

Stereo- and regioselective synthesis of squalene tetraepoxide.

Squalene tetraepoxide, a putative biosynthetic precursor to a variety of oxacyclic triterpenoid natural products, has been efficiently synthesized by anionic coupling of two farnesol-derived diepoxides, which have arisen from electronic control of the regioselectivity in organocatalytic enantioselective epoxidations.

1,5-Alpha-D-mannoseptanosides, ring-size isomers that are impervious to alpha-mannosidase-catalyzed hydrolysis.

1,5-D-mannoseptanosyl di- and trisaccharide ring-size isomers of the corresponding mannopyranosyl oligosaccharides have been prepared. Remarkably, these compounds show no inhibition of the alpha-mannosidase-catalyzed hydrolysis of p-nitrophenyl-alpha-D-mannopyranoside.