posted on 2021-04-22, 12:38authored byLiselle Atkin, Angus Robertson, Jonathan M. White, Mark A. Rizzacasa
The total synthesis of viridiofungins
A (1) and B
(2) via β-lactone 3 in 13 steps is
reported. Key steps included an HF-mediated rearrangement of cyclobutene
diester 9 to form a bicyclic lactone 6,
an olefin cross metathesis between disubstituted alkene 3 and alkene 4 in which isomerization was suppressed,
and a novel β-lactone ring opening to form the amide. Deprotection
then gave either viridiofungin A (1) or B (2) in high yield.