Efficient synthesis of the C-1-C-11 fragment of the tedanolides. The nonaldol aldol process in synthesis

[GRAPHICS] The nonaldol aldol process developed in our laboratories has been applied t o the synthesis of a C-1-C-11 fragment 22 of the novel macrocyclic cytotoxi c agents tedanolide and 13-deoxytedanolide 1 and 2. The commercially availa ble hydroxy ester 7 was converted in 24 steps into compound 22 using two no naldol aldol reactions.