In this task, you are given a sentence. You are expected to recognize the name of any form of chemical substances. Although there might be several correct answers, you need to write one of them.
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Question: In vivo activity of the potent oxytocin antagonist on uterine activity in the rat.

Answer: oxytocin


Question: The presence of D-fagomine in the human diet from buckwheat-based foodstuffs.

Answer: D-fagomine


Question: Synthesis and biological evaluation of novel pyrrolidine-2,5-dione derivatives as potential antidepressant agents. Part 1.

Answer:
pyrrolidine-2,5-dione