The present invention provides novel compounds of Formula (I), and pharmaceutically compositions thereof. Compounds of Formula (I) are inhibitors of histone deacetylases (HDACs) and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMGR). Also provided are methods of using the compounds and pharmaceutical compositions for inhibiting the activity of HDACs and HMGR, treating diseases associated with HDACs or HMGR (e.g., cancer, hypercholesterolemia, an acute or chronic inflammatory disease, autoimmune disease, allergic disease, pathogen infection, neurodegenerative disease, and a disease associated with oxidative stress), or inhibiting drug resistance of cancer cells.