Total Synthesis of (±)-Sorocenol B Employing Nanoparticle Catalysis

The total synthesis of (±)-sorocenol B has been accomplished featuring key steps including silver nanoparticle (AgNP)-catalyzed Diels–Alder cycloaddition and late-stage Pd(II)-catalyzed oxidative cyclization. The synthetic natural product exhibited low micromolar cytotoxic activity against a number of human cancer cell lines

Total Syntheses of Graphisin A and Sydowinin B

Efficient syntheses of the highly substituted benzophenone graphisin A and the xanthone sydowinin B are described. Key steps involve aryl anion addition to substituted benzaldehyde derivatives, subsequent methyl ester installation, and dehydrative cyclization. Oxidation of graphisin A led to a spirodienone derived from a highly substituted benzoquinone intermediate

Total Synthesis of (±)-7-<i>epi</i>-Nemorosone

A concise total synthesis of (±)-7-<i>epi</i>-nemorosone is reported. Our synthetic approach establishes a viable route to polycyclic polyprenylated acylphloroglucinol natural products (PPAP’s) bearing a C-7 <i>endo</i> prenyl side chain. Key steps include retro-aldol-vinyl cerium addition to a hydroxy adamantane core scaffold and palladium-mediated deoxygenation

Studies toward the Synthesis of the Epoxykinamycin FL-120B′: Discovery of a Decarbonylative Photocyclization

Photo-Friedel–Crafts acylation of a naphthoquinone was attempted in an effort to access a diazobenzofluorenone en route to the epoxykinamycin natural product FL-120B′. Photoirradiation of the naphthoquinone substrate which resulted in the unexpected formation of a tetracyclic naphthofuran <i>via</i> a decarbonylative photocyclization process is described

Total Synthesis of (±)-7-<i>epi</i>-Nemorosone

A concise total synthesis of (±)-7-<i>epi</i>-nemorosone is reported. Our synthetic approach establishes a viable route to polycyclic polyprenylated acylphloroglucinol natural products (PPAP’s) bearing a C-7 <i>endo</i> prenyl side chain. Key steps include retro-aldol-vinyl cerium addition to a hydroxy adamantane core scaffold and palladium-mediated deoxygenation

Remodeling of Fumagillol: Discovery of an Oxygen-Directed Oxidative Mannich Reaction

An efficient, two-step construction of highly complex alkaloid-like compounds from the natural product fumagillol is described. This approach, which mimics a biosynthetic cyclase/oxidase sequence, allows for rapid and efficient structure elaboration of the basic fumagillol scaffold with a variety of readily available coupling partners. Mechanistic experiments leading to the discovery of an oxygen-directed oxidative Mannich reaction are also described

Metal-Catalyzed Cascade Rearrangements of 3‑Alkynyl Flavone Ethers

Metal-mediated rearrangements of 3-alkynyl flavone ethers are reported. The overall process involves 5-<i>endo</i> enyne cyclization to a platinum-containing spiro-oxocarbenium intermediate which may be trapped with methanol to produce spirodihydrofurans or further rearranged to afford either allenyl chromanediones or benzofuranones

Divergent Total Syntheses of Rhodomyrtosones A and B

Herein, we report total syntheses of the tetramethyldihydroxanthene natural product rhodomyrtosone B and the related bis-furan β-triketone natural product rhodomyrtosone A. Nickel-(II)-catalyzed 1,4-conjugate addition of an α-alkylidene-β-dicarbonyl substrate was developed to access the congener rhodomyrtosone B, and oxygenation of the same monoalkylidene derivative followed by cyclization was employed to obtain the bis-furan natural product rhodomyrtosone A

Metal-Catalyzed Cascade Rearrangements of 3‑Alkynyl Flavone Ethers

Metal-mediated rearrangements of 3-alkynyl flavone ethers are reported. The overall process involves 5-<i>endo</i> enyne cyclization to a platinum-containing spiro-oxocarbenium intermediate which may be trapped with methanol to produce spirodihydrofurans or further rearranged to afford either allenyl chromanediones or benzofuranones

Metal-Catalyzed Cascade Rearrangements of 3‑Alkynyl Flavone Ethers

Metal-mediated rearrangements of 3-alkynyl flavone ethers are reported. The overall process involves 5-<i>endo</i> enyne cyclization to a platinum-containing spiro-oxocarbenium intermediate which may be trapped with methanol to produce spirodihydrofurans or further rearranged to afford either allenyl chromanediones or benzofuranones