Montelukast Bis-sulfide, a mixture of diastereomers, is primarily utilized in research and development within the pharmaceutical industry. It serves as an intermediate in the synthesis of Montelukast, a leukotriene receptor antagonist widely prescribed for the management of asthma and allergic rhinitis. This compound is critical in studying the metabolic pathways and degradation products of Montelukast, helping to understand its stability and efficacy. Additionally, it aids in the development of analytical methods for quality control and impurity profiling in drug manufacturing processes. Researchers also explore its potential in optimizing synthetic routes to enhance the production efficiency of Montelukast.