Used primarily as a reference standard in pharmaceutical quality control, this compound serves as a key impurity marker in the synthesis and analysis of citalopram, a selective serotonin reuptake inhibitor (SSRI) used to treat depression. It helps in validating analytical methods such as HPLC and LC-MS to ensure the purity and safety of citalopram formulations. Its presence is monitored closely during manufacturing to control degradation products and by-products, supporting compliance with regulatory guidelines. Due to its structural similarity to citalopram, it also aids in stability studies and process optimization in drug development.