<unk> , also azulon or 1,4-dimethyl-7-isopropylazulene, is a dark blue crystalline hydrocarbon and a derivative of azulene.  Specifically, it is a bicyclic sesquiterpene that occurs naturally as a constituent of some essential oils, mainly oil of guaiac and chamomile oil, which also serve as its commercial sources. Various soft corals also contain<unk>  as a principal pigment.<unk>  is an FDA-approved cosmetic color additive. It is also a common component of cosmetics like shampoos or skin care products with other skin soothing compounds such as allantoin.<unk>  has applications as an anti-ulcer drug, and can be also used as a volatile dye with a known evaporation rate to indicate end of use of various products (such as insecticide strips.)
Guaiazulene
Nifurtoinol
Thiothixene
Tiotropium
Diflorasone
Methapyrilene
Roflumilast
Clobetasone