TASK DEFINITION: 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.
PROBLEM: The (R)-omeprazole hydroxylation index reflects CYP2C19 activity in healthy Japanese volunteers.

SOLUTION: (R)-omeprazole

PROBLEM: Activation of the anti-cancer agent upamostat by the mARC enzyme system.

SOLUTION: upamostat

PROBLEM: Brugada syndrome without mutation of the cardiac sodium channel gene in a Taiwanese patient.

SOLUTION:
sodium