YM-90709 is primarily used in biochemical and pharmacological research as a selective antagonist for the group II metabotropic glutamate receptors (mGluR2/3). It is employed to study the role of these receptors in synaptic transmission, neural circuits, and neurological disorders. Due to its ability to cross the blood-brain barrier, YM-90709 is useful in in vivo experiments investigating glutamate signaling in animal models. It has been applied in studies related to anxiety, schizophrenia, and depression, helping researchers understand how modulation of glutamatergic activity affects behavior and cognition. Its use remains confined to experimental settings and is not approved for clinical or therapeutic use.