Synthesis, odour characteristics and antibacterial activities of the stereoisomeric forms of whisky lactone and its thiono analogues

Four stereoisomers of whisky lactone were selectively synthesized in over 99% enantiomeric excess using an amino acid derivative as a resolving agent. Cbz‐L‐proline was the most effective resolving agent, and both trans ‐ and cis ‐stereoisomers were comparatively easily separated. Odour characteristics of whisky thionolactone were different among four stereomeric isomers, and only (3 S ,4 R )‐whisky thionolactone had mushroom and cis ‐jasmone like note. Among all isomers, only (3 R ,4 S )‐whisky lactone showed antibacterial activities against Staphylococcus aureus . Whisky thionolactone had higher activities than whisky lactone, and (3 R ,4 S )‐whisky thionolactone showed the strongest activities of all tested samples. Copyright © 2016 John Wiley & Sons, Ltd.