Skatole

Skatole, or 3-methylindole, is a malodorous constituent of mammalian faeces produced by the breakdown of tryptophan in the digestive tract. It has a floral aroma in low concentrations, contributing to the pleasant scent of flowers such as jasmine and orange blossom, but can also turn into an animal, almost dirty note. The fragrance note, which is also produced synthetically, is not commonly used but is very useful in perfumes with floral and animalic main features in the composition.