6-bromo-2-naphthoic acid can be used as an intermediate in pharmaceutical synthesis. For example, adapalene, a derivative of naphthoic acid, belongs to the third generation of retinoic acid drugs. Its chemical name is 6 - [3 - (1-adamantyl) - 4-methoxyphenyl] - 2-naphthoic acid. It is an anti acne drug developed by France's gaudemai pharmaceutical company. Adapalene is a retinol compound that binds to the specific nuclear retinoic acid receptor like all trans retinoic acid, But the difference is that it can selectively bind to retinoic acid receptors related to keratinocyte proliferation and differentiation γ, It does not bind to cytoplasmic retinoic acid binding protein. Its mechanism is mainly to reduce the formation of micro acne by regulating the differentiation of hair follicle epithelial cells.