A Short Enantioselective Total Synthesis of Dammarenediol II

Mimicking Biosynthesis: Total Synthesis of the Triterpene Natural Product Abudinol B from a Squalene‐like Precursor

“…To more effectively promote the initial tricyclization cascade to the fused tricyclic network of abudinol B as observed in the proposed biogenetic intermediate 4, the enolsilane at C14-C15 of 10 was introduced for efficient nucleophilic termination of the cascade cyclization. Diepoxybromide 6 was coupled with the Brook rearrangement product of the lithium alkoxide of 9, [8,9] providing the enolsilane 10 exclusively as the Z isomer. The [*] Dr. R. Tong …”

Multicomponent Reactions in the Total Synthesis of Natural Products

“…From cyclic ketone 52, selective ozonolysis of the exocyclic alkene and McMurry cyclization completed this short synthetic sequence to afford target 44. A similar synthetic strategy was also used for the synthesis of dammarenediol II 45 [31].…”

Contiguous Stereogenic Quaternary Carbons: A Daunting Challenge in Natural Products Synthesis

“…We begin with the enantioselective synthesis of dammarenediol II (3), a congener of dammaradienol (2), reported in 1996 by Corey and Lin (5). Their retrosynthetic analysis disassembles the three cyclohexane rings and the vicinal quaternary carbon centers of 3 to furnish polyene 4 (Scheme 2).…”