posted on 2021-11-12, 17:05authored byJiaxin Xie, Xin Liu, Nan Zhang, Shinyoung Choi, Guangbin Dong
Here
we report the total synthesis of phainanoid A, a unique dammarane-type
triterpenoid (DTT), using an unusual bidirectional synthetic strategy.
It features two transition-metal-mediated highly diastereoselective
transformations to access the two challenging strained ring systems
that branch toward opposite directions from the tricyclic core. This
work also highlights the strategic use of ketones (or enol triflates)
as versatile handles for rapid growth of molecular complexity in all
key transformations, which paves the way for efficient preparations
of complex and biologically significant DTTs.