Stereoselective synthesis of a synthon for the natural electron transfer inhibitors myxalamide D and piericidin A
Abstract
The trimethylsilyl enolate 5 of (1′R,2′S)-N-methylephedrine propionate was condensed with tiglic aldehyde to afford the (1′R,2′S,2S,3R)-ester 6 with high stereoselectivity; conversion into the aldehyde 8 was effected without epimerisation, and the sequence 8→9→11→12→13 afforded in 84% e.e. the (+)-(4R,5R,2E,6E)-sulphone 13, a synthon for the electron-transport inhibitors myxalamide D 1 and piericidin A 3, as well as the actinopyrones 4.