Provided is a composition for inhibiting anti-cancer drug resistance comprising a compound represented by Chemical Formula 1 below as an active ingredient:






(wherein,
R1 and R2 are each independently hydrogen, substitutable linear or branched C1-C12 alkyl, substitutable C3-C12 cycloalkyl, or substitutable C6-C18 aryl,
R3 is carboxyl, hydroxyl, or acetyl, and
the substitution is performed by oxygen, nitrogen, sulfur, linear or branched C1-C6 alkyl, C6-C20 aryl, halogen, or a combination thereof).