Total Synthesis of (+)-Pestalofone A and (+)-Iso-A82775C

Total Syntheses of Chloropupukeananin and Its Related Natural Products

Chloropupukeananin is a natural product that inhibits HIV-1 replication and has antitumor activity. Its structure consists of a chlorinated tricyclo[4.3.1.03,7]decane core skeleton with an array of highly oxidized multifunctional groups. In the biosynthesis of chloropupukeananin, (+)-iso-A82775C and (−)-maldoxin are employed as biosynthetic precursors for the intermolecular Diels–Alder and carbonyl–ene reactions, followed by the migration of the p-orcellinate group. Chloropupukeanolides and chloropestolides are intermediates and isomers in biosynthesis; their unique chemical structures and biosynthetic pathways have attracted significant attention from synthetic chemists. In this review, I present the synthetic studies on chloropupukeananin and its related compounds that have been conducted thus far.

Biomimetic Total Syntheses of (+)-Chloropupukeananin, (-)-Chloropupukeanolide D, and Chloropestolides

Chloropupukeananin, chloropupukeanolides, and chloropestolides are a family of structurally complex bioactive natural products that possess highly functionalized tricyclo[4.3.1.0^3,7]decane or bicyclo[2.2.2]octane skeletons. Biosynthesis of the chloropupukeananin family is triggered by the intermolecular heterodimeric Diels-Alder reaction between maldoxin and iso-A82775C; however, the enzymes involved have not yet been identified. We herein report the one-pot biomimetic synthesis of chloropupukeananin and chloropupukeanolide D. Moreover, the effect of the solvent on the intermolecular Diels-Alder reaction of siccayne and maldoxin suggested that the biosynthesis of the chloropupukeananin family involves a Diels-Alderase-catalyzed heterodimeric Diels-Alder reaction.

Deciphering the Chameleonic Chemistry of Allenols: Breaking the Taboo of a Onetime Esoteric Functionality

The allene functionality has participated in one of the most exciting voyages in organic chemistry, from chemical curiosities to a recurring building block in modern organic chemistry. In the last decades, a special kind of allene, namely, allenol, has emerged. Allenols, formed by an allene moiety and a hydroxyl functional group with diverse connectivity, have become common building blocks for the synthesis of a wide range of structures and frequent motif in naturally occurring systems. The synergistic effect of the allene and hydroxyl functional groups enables allenols to be considered as a unique and sole functionality exhibiting a special reactivity. This Review summarizes the most significant contributions to the chemistry of allenols that appeared during the past decade, with emphasis on their synthesis, reactivity, and occurrence in natural products.