Adapalene-13C6 (CD271-13C6) is the 13C-labeled Adapalene (HY-B0091). Adapalene (CD271), a third-generation synthetic retinoid, is widely used for the research of acne. Adapalene is a potent RAR agonist, with AC50s of 2.3 nM, 9.3 nM, and 22 nM for RARbeta, RARgamma, RARalpha, respectively. Adapalene also inhibits the enzymatic activity of GOT1 in a non-competitive manner. Adapalene exhibits anti-tumor activity[1][2][3].