Au-Catalyzed Asymmetric Polyene Cyclization and Its Application in the Total Synthesis of (+)-2-Ketoferruginol, (+)-Fleuryinol B, (+)-Salviol, and (−)-Erythroxylisin A

Abstract

A catalytic asymmetric 1,3-acyloxy shift/polyene cyclization cascade has been achieved with good enantioselectivities under the catalysis of the chiral Au(I) reagent. The synthetic utility of this method has been showcased by the catalytic asymmetric total syntheses of (+)-2-ketoferruginol, (+)-fleuryinol B, and (+)-salviol. Notably, the first enantioselective total synthesis of (−)-erythroxylisin A has also been realized in 15 steps.

Catalytic Asymmetric Total Synthesis of (−)-Garryine via an Enantioselective Heck Reaction

“…Dienone 6 could be traced backed to 7 via functional group (FG) manipulations. While enantioselective synthetic methods have been known to access chiral 6/6/6 tricyclic compounds resembling 7 with a substituted phenyl C ring and a C10 quaternary stereocenter, − approaches to the corresponding products with C19 functionalities are limited. ,− In particular, a functionalized C19 moiety was required for the construction of the characteristic piperidine E ring in diterpenoid alkaloids . Thus, we envisioned a new asymmetric Heck reaction of triflate 8 containing an enoate group for the synthesis of the 6/6/6 tricyclic intermediate 7 , which represented the third key step in our synthetic plan.…”

Photocatalytic Tandem Radical Cyclization Enables Expeditious Total Synthesis of Epoxyhinokiol Analogues for Anticancer Activity Evaluation

“…These abietane diterpenoids exhibit a wide variety of biological activities, such as antibacterial, anti-inflammatory, antioxidant, antitumor, and antioxidant effects. Due to their structural diversity and biological significance, the chemical synthesis of abietane diterpenoids has always been an important theme in the synthetic community …”