Recent advances in abietane/icetexane synthesis

Total synthesis of (±)-villosin C and (±)-teuvincenone B

“…The synthetic challenge is mainly embedded in the highly oxidized nature (9 out of 10 carbons of the B/C ring are unsaturated and 5 are directly attached to oxygen) and that the C ring is a fully substituted benzene moiety. Although there is a plethora of synthetic studies on C ring aromatized abietane diterpenoids, 9 seldom has targeted those with high oxidation states and fully substituted benzene in this family, 10 and the total synthesis of villosin C ( 5 ) and teuvincenone B ( 4 ) are yet to be reported. In an initial synthetic study, one of us (Mao) obtained an elaborated intermediate ( 8 ) with fully established carbon skeleton and ring system.…”

Total Synthesis of Diterpenoid Quinone Methide Tumor Inhibitor, (+)-Taxodione

“… Biosynthetically, tetraterpenoids 4 and 5 are assumed to be derived from the naturally occurring taxodione ( 1 ) via the “red bond” as shown in Figure . The biological profile of these dimeric abietanes is yet to be evaluated through chemical synthesis …”

Recent Developments with Icetexane Natural Products

“…Icetexane natural products were the subject of a 2009 review [1] (including a proposed classification system for this family of natural products) and since that time alone >50 novel icetexanes have been discovered and several new synthetic approaches to the characteristic 6‐7‐6 scaffold have been reported. The synthetic relationship between abietanes and icetexanes and approaches to both have recently been explored [9] . The focus of this review includes a summary of these newly described natural products and any known biological activity, an overview of novel approaches to icetexanes since 2009, as well as a proposed new descriptive class of icetexane natural products that falls outside the realm of previously reported structures.…”

“…The synthetic relationship between abietanes and icetexanes and approaches to both have recently been explored. [9] The focus of this review includes a summary of these newly described natural products and any known biological activity, an overview of novel approaches to icetexanes since 2009, as well as a proposed new descriptive class of icetexane natural products that falls outside the realm of previously reported structures.…”