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: Advances in antihypertensive combination therapy: benefits of low-dose thiazide diuretics in conjunction with omapatrilat, a vasopeptidase inhibitor.

Answer: thiazide


Question: Efficient induction of apoptosis in HeLa cells by a novel cationic porphycene photosensitizer.

Answer: porphycene


Question: PPARgamma controls CD1d expression by turning on retinoic acid synthesis in developing human dendritic cells.

Answer:
retinoic acid