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: Oncolytic activity and mechanism of action of a novel L-cysteine derivative, L-cysteine, ethyl ester, S-(N-methylcarbamate) monohydrochloride.

Answer: L-cysteine

Question: Stimulation of N-methyl-D-aspartate receptors modulates Jurkat T cell growth and adhesion to fibronectin.

Answer: N-methyl-D-aspartate

Question: Site dependent intestinal absorption of darunavir and its interaction with ketoconazole.

Answer:
darunavir