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: Desvenlafaxine succinate identifies novel antagonist binding determinants in the human norepinephrine transporter.
Example Output: norepinephrine

Example Input: Structure-based design, synthesis and evaluation of novel anthra[1,2-d]imidazole-6,11-dione derivatives as telomerase inhibitors and potential for cancer polypharmacology.
Example Output: anthra[1,2-d]imidazole-6,11-dione

Example Input: Cloning, sequencing, structural and molecular biological characterization of placental protein 20 (PP20)/human thiamin pyrophosphokinase (hTPK).
Example Output:
thiamin