Indolin-1-amine hydrochloride is primarily used in pharmaceutical research and development as a key intermediate in the synthesis of various biologically active compounds. It plays a significant role in the creation of molecules with potential therapeutic applications, particularly in the field of oncology and neurology. Researchers utilize this compound to develop inhibitors targeting specific enzymes or receptors involved in disease pathways. Additionally, it is employed in the study of chemical reactions and mechanisms, aiding in the discovery of novel drugs. Its stability and reactivity make it a valuable component in organic synthesis, contributing to advancements in medicinal chemistry.