Acyclic bastadins

Bastadin-6 can be produced by phenolic oxidation of the corresponding acyclic precursor, bastadin-2 (229). Bis-p-methoxybenzyl bastadin-2 (344) was converted to tribenzyl bastadin-2 (347), which was further treated with Bt2 to afford dibromobastadin-2 tribenzyl ether (348). Under the same procedure, 348 was oxidized with Ti(N03)3 to afford two macrocychc dienones (349 and 350). Compound 349 was reduced with Zn to give the tribenzyl ether 351. Finally, 351 was subjected to hydrogenlysis, using Pd black to afford bastadin-6 (229). Bastadin-6 trimethyl ether was produced in a similar procedure (231). 

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