Total Synthesis of Lajollamycin B

The first total synthesis of lajollamycin B, a structurally novel nitro-tetraene spiro-beta-lactone/gamma-lactone antibiotic, is described. The convergent synthesis involves the construction of the C8 '-C11 ' nitrodienylstannane and its coupling with the segment prepared from the C1 '-C7 ' omega-iodoheptadienoic acid and the right-hand heterocyclic fragment, which has been utilized for our previous syntheses of oxazolomycin A. The revision of the geometry of the terminal Delta(10 ', 11 ')-double bond from E to Z is also described for the structure of natural lajollamycin B.