Provided herein are compounds of Formulae (I) and (II), and pharmaceutically acceptable salts, solvates, hydrates, polymorphs, co-crystals, tautomers, stereoisomers, isotopically labeled derivatives, prodrugs, and compositions thereof. Also provided are methods and kits involving the compounds or compositions disclosed herein for treating and/or preventing proliferative diseases, cancers, carcinoma lung cancer, breast cancer, liver cancer, pancreatic cancer, gastric cancer, ovarian cancer, colon cancer, colorectal cancer, leukemia, sarcoma and/or cardiovascular diseases in a subject in need thereof. In certain embodiments, the sarcoma is Ewing' s sarcoma. Provided are methods of inhibiting a histone demethylase in a subject and/or in a cell, tissue, or biological sample. In certain embodiments, the histone demethylase is a KDM. In certain embodiments, the KDM is KDM5. In certain embodiments, the biological sample is a cell. In certain embodiments, the biological sample is a tissue.