Pharmaceutical intermediates are the compounds that make up the components of an active pharmaceutical ingredient (API). Pharmaceutical intermediates are produced as by-products during the production of APIs. each reaction in the API production process produces a variety of different pharmaceutical intermediates, which can only be transformed into APIs by further molecular changes or refinement. Intermediates can be isolated or not. Pharmaceutical intermediates are used in the production of APIs and are also used by various pharmaceutical and biopharmaceutical companies for R&D purposes.