posted on 2007-09-26, 00:00authored byBarry M. Trost, Yimin Hu, Daniel B. Horne
The first total synthesis of (+)-frondosin A was accomplished in 19 longest linear and 21 total
steps from commercially available materials. The key features of the synthesis include a Ru-catalyzed
[5+2] cycloaddition, a Claisen rearrangement, and a ring expansion to construct the core of the frondosin
A in a diastereoselective and regioselective fashion. This is the first application of a Ru-catalyzed [5+2]
cycloaddition in the total synthesis of a natural product. Through this synthesis, the absolute configuration
of (+)-frondosin A was established.