Salicylic acid is a monohydroxybenzoic acid that is benzoic acid with a hydroxy group at the ortho position. It is obtained from the bark of the white willow and wintergreen leaves. It has a role as an antiinfective agent, an antifungal agent, a plant hormone, a keratolytic drug, an EC 1.11.1.11 (L-ascorbate peroxidase) inhibitor, a plant metabolite and an algal metabolite. It is a conjugate acid of a salicylate. Salicylic acid , a phenolic phytohormone, can alleviate the damaging effects of the triple stress by improving the antioxidant system, although these effects differed depending on characteristic of the hull of the grain. Salicylic acid plays a key role in regulation of plant immune responses to different attackers.

(R)-mandelic acid is the (R)-enantiomer of mandelic acid. It has a role as a human xenobiotic metabolite. It is a conjugate acid of a (R)-mandelate. It is an enantiomer of a (S)-mandelic acid.

Benvitimod is a stilbenoid.

Acitretin has immunomodulatory effect, and low dose acitretin therapy is safe, well tolerated and partially effective in chemoprophylaxis of skin cancer in renal transplant recipients, it for chemoprevention of non-melanoma skin cancers in renal transplant recipients. Acitretin dramatically improves the results of UV-B treatment in patients with severe psoriasis and it markedly decreases the effective cumulative UV-B dose. Acitretin in the treatment of severe lichen sclerosus et atrophicus of the vulva. Acitretin therapy is effective for psoriasis associated with human immunodeficiency virus infection. All-trans-acitretin is a retinoid, an acitretin and an alpha,beta-unsaturated monocarboxylic acid. It has a role as a keratolytic drug.

Aloesin is a member of chromones.