Studies on analogs of DAMASCENOLIDETM: Part 4. Synthesis and odor evaluation of sulfur-containing analogs of DAMASCENOLIDETM.

DAMASCENOLIDETM [1, 4-(4-methylpent-3-en-1-yl)furan-2(5H)-one], which is isolated from damask rose, is a useful aroma compound with a citrus-like odor. We have previously reported on the synthesis and odor properties of 34 analogs of 1 as part of our new aroma compound development project. In order to develop better aroma compounds and to gather more information on structure-odor relationships, 6 novel sulfur-containing analogs of 1 were synthesized. Odor evaluation revealed that their odors differed significantly from those of the corresponding sulfur-free compounds. The introduction of a sulfur atom does not necessarily result in a sulfur-like odor. In particular, the 2(5H)-thiophenone analogs gave waxy, oily, and lactone-like odors that are uncharacteristic of sulfur-containing compounds. In many synthesized analogs, the introduction of a sulfur atom led to an increase in odor intensity, as expected.