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: Adipose tissue as a source of nicotinamide N-methyltransferase and homocysteine.

Answer: nicotinamide


Question: T-Cells from HLA-B*57:01+ Human Subjects Are Activated with Abacavir through Two Independent Pathways and Induce Cell Death by Multiple Mechanisms.

Answer: Abacavir


Question: Signaling through Gi family members in platelets. Redundancy and specificity in the regulation of adenylyl cyclase and other effectors.

Answer:
adenylyl