2-Azaspiro[3.5]nonane is primarily used as a building block in organic synthesis, particularly in the development of pharmaceuticals. Its unique spirocyclic structure makes it valuable for creating complex molecules with specific biological activities. It is often employed in the synthesis of drug candidates targeting neurological disorders, such as antidepressants and antipsychotics, due to its ability to interact with neurotransmitter systems. Additionally, it serves as a key intermediate in the production of compounds with potential anti-inflammatory and analgesic properties. Its versatility in medicinal chemistry also extends to the development of ligands for receptor binding studies, aiding in the discovery of new therapeutic agents.