4-Hydroxybiphenyl ethers

thumb|Adapalene Gel, sold as trade name Differin in China

Anidulafungin (INN) (sold under the brand name Eraxis among others, is a semisynthetic echinocandin used as an antifungal medication. It may also have application in treating invasive Aspergillus infection when used in combination with voriconazole. It is a member of the class of antifungal drugs known as the echinocandins; its mechanism of action is by inhibition of (1→3)-β-D-glucan synthase, an enzyme important to the synthesis of the fungal cell wall.

Trifarotene, sold under the brand name Aklief, is a medication for the topical treatment of acne vulgaris. It is a retinoid; specifically, a fourth-generation selective retinoic acid receptor (RAR)-γ agonist.