N-Methyl-1-((trans-4-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)cyclohexyl)methyl)methanesulfonamide maleate is a maleate salt form of a small molecule compound. Its core structure features a 7H-pyrrolo[2,3-d]pyrimidine scaffold, which is a privileged heterocyclic motif in medicinal chemistry, particularly for kinase inhibition. This compound is a key intermediate in the synthesis of Sapanisertib (also known as TAK-228 or MLN0128). Sapanisertib is a potent, selective, and ATP-competitive dual inhibitor of the mammalian target of rapamycin (mTOR) kinase, specifically targeting both mTORC1 and mTORC2 complexes. As an investigational new drug, it has been evaluated in numerous clinical trials for the treatment of various solid tumors and hematological malignancies. The maleate salt form is typically employed to improve the physicochemical properties, such as solubility and crystallinity, of the active pharmaceutical ingredient (API) for formulation development. The synthesis and characterization of this intermediate are critical steps in the manufacturing process of the final drug substance.