Novel asymmetric syntheses of (−)-malyngolide and (+)- epi-malyngolide

Abstract

The diastereo- and enantioselective synthesis of (−)-malyngolide [(S, R)- 1], an antibiotic against Mycobacterium smegmatis and Streptococcus pyogenes, using the asymmetric Carroll rearrangement as key step is described. Furthermore, the diastereo- and enantioselective synthesis by double α, α′-alkylation using SAMP/RAMP hydrazone methodology affords the diastereomer (+)- epi-malyngolide [(S, S)- 1]. The diastereo- and enantioselective synthesis of the anti-biotic (−)-malyngolide via asymmetric dianionic Carroll rearrangement is described. In addition an α, α′-double alkylation pathway using the SAMP/RAMP-hydrazone methodology leading to (+)- epi-malyngolide is carried out. [Display omitted]