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: Exposure to valproic acid inhibits chondrogenesis and osteogenesis in mid-organogenesis mouse limbs.

Answer: valproic acid

Question: Suppression of NF-kappaB activity by sulfasalazine is mediated by direct inhibition of IkappaB kinases alpha and beta.

Answer: sulfasalazine

Question: Relative expression of cholesterol transport-related proteins and inflammation markers through the induction of 7-ketosterol-mediated stress in Caco-2 cells.

Answer:
cholesterol