Efficient synthesis of the C1-C11 fragment of the tedanolides.: The nonaldol aldol process in synthesis

[GRAPHICS] The nonaldol aldol process developed in our laboratories has been applied to the synthesis of a C-1-C-11 fragment 22 of the novel macrocyclic cytotoxic agents tedanolide and 13-deoxytedanolide 1 and 2. The commercially available hydroxy ester 7 was converted in 24 steps into compound 22 using two nonaldol aldol reactions.