Firmenich to tackle allergens

Researchers at Swiss flavours and fragrances company Firmenich have identified chemicals that might be able to replace salicylates in perfumed products, reducing the risk of allergies. Salicylates are widely used in perfumed products, from fine fragrance to functional items such as fabric softener. Common ones include benzyl salicylate, methyl salicylate, cis 3 hexenyl salicylate and iso amyl salicylate.

Salicylates have an enhancing effect that is greatly prized in perfumery, but they can also be unstable and cause allergies in some people. Their use is rapidly being restricted.

In response to this, Firmenich chemist Jean-Marc Gaudin and his colleagues set out to explore a series of compounds that they thought might possess similar olfactory notes to salicylates. “We explored carba-analogues, cyclic β-keto esters and cyclic β-diketones as salicylate analogues,” said Gaudin. “Applying the simple concept of three- dimensional structure similarity was very fruitful. Salicylate carba-analogues and β- keto esters, especially compounds 5, 7 and 10 for the first series and 27 and 28 for the second series, proved to be the most interesting type of compounds. For example, 1-(2-hydroxyphenyl)-3-phenyl-1-propanone (10), which can be found in nature, has an excellent olfactory profile with a dual floral-animal note.” The team concluded that these compounds are the first credible alternative to salicylates.