New alicyclic musks: the fourth generation of musk odorants

Musk odorants are one of the most important classes of fragrances in perfumery because they impart sensuality to perfume-oil compositions. Among the three well-known classes of musks, a new and very exciting generation of musk odorants, the so-called alicyclic musks, was discovered recently, of which Helvetolide (2) and Romandolide (3) are the most popular representatives so far. To find new, structurally related alicyclic musks, we have synthesized a library of 114 unique alicyclic molecules with modified cyclohexyl moieties. The olfactory properties of all compounds were evaluated to identify the structural requirements to be met for a musk odorant.     

Three-dimensional structure model for benzenoid musks expressed by computer graphics

Structures of two strong benzenoid musks, 3,5-di-t-butylacetophenoneand 5-acetyl-1,1,2,3,3,6-hexamethylindan, were optimized byPM3 (MOPAC Ver.5). Based on these structures, a three-dimensionalstructure model for benzenoid musks was constructed. This structuremodel is expressed as a box of about 12 x 11 x 6.5 Å Whichcircumscribes musk molecules. The box contains (i) a smallerbox of about 7.5 x 11 x 6.5 Å Which approximates the hydrophobicbulky moiety of benzenoid musks; (ii) the position of the benzenering located in the smaller box; and (iii) the binding pointon an odor receptor assumed to interact with an oxygen atomof the functional group in the benzenoid musks. The validity of this structure model was examined by applyingit to structures of 40 benzenoids (30 musks and 10 odorless).As a result, 37 out of the 40 benzenoids were correctly discriminatedto be odoriferous or odorless by referring them to this structuremodel.