An Efficient Asymmetric Synthesis of Tarchonanthuslactone

Article abstract of DOI:10.1002/ejoc.200300412

An efficient and straightforward ten-step asymmetric synthesis of the polyketide tarchonanthuslactone (1) in good overall yield (21% starting from chloro lactone 5) and with excellent diastereomeric and enantiomeric excesses (de, ee ≥ 96%) is described. The new synthetic route is based on the α,β-unsaturated δ-lactone building block 5, available in enantiopure form (ee > 99%) through an enzymatic procedure, and its conversion into methyl ketone 11 by an Umpolung strategy. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.