As an acne treatment, resorcinol has a keratolytic effect, causing dead cells to slough off. The top layer of skin is removed, and pores unclogged.
It is often used with sulfur, to prevent the whiteheads and blackheads that sufur causes as a side-effect when used to treat inflamed pimples.
Like salicylic acid, it is also used to treat warts, psoriasis, and other skin conditions.
resorcinol: InChI=1/C6H6O2/c7-5-2-1-3-6(8)4-5/h1-4,7-8H