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.

Example input: Inhibition of the human ether-a-go-go-related gene (HERG) potassium channel by cisapride: affinity for open and inactivated states. 
Example output: potassium
Example explanation:  Potassium is a type of electrolyte mineral that helps our nerves to function and muscles to contract. Hence, it should be tagged as chemical.
Q: Discovery of 4-phenyl-2-phenylaminopyridine based TNIK inhibitors.
A:
4-phenyl-2-phenylaminopyridine