A formal synthesis of (-)-mycalamide A.
Novel strategies are developed for an efficient formal synthesis of (-)-mycalamide A. The left-hand side (-)-7-benzoylpederic acid is synthesized from (2S,3S)-2,3-epoxybutane. The key features include a highly regioselective Ru-catalyzed alkene-alkyne coupling reaction and a novel way to control the challenging C(7) stereocenter. The right-hand side was synthesized from (R)-pantolactone. The complex trioxodecalin core is constructed with two Pd(0)-catalyzed O-pi-allyl cyclizations. The first one is chemoselective, while the second one is highly diastereoselective. Three additional steps would be required to complete a total synthesis of (-)-mycalamide A.
Trost
Barry M
BM
Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Yang
Hanbiao
H
Probst
Gary D
GD
D000818:Animals; D008387:Marine Toxins / Q000138:chemical synthesis; D011161:Porifera / Q000737:chemistry; D011714:Pyrans / Q000138:chemical synthesis*; D013237:Stereoisomerism
D008387:Marine Toxins; D011714:Pyrans; C059646:mycalamide A