UNC9994是阿立哌唑的一种类似物，作为一种功能选择性的β-阻遏蛋白偏向性D2受体激动剂，它通过促进β-arrestin-2募集（EC50<10 nM）、易位并拮抗Gi介导的cAMP产生，发挥抗精神病活性。

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