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: Distinct role of PYK2 in mediating thromboxane generation downstream of both G12/13 and integrin αiibβ in platelets.
Example Output: thromboxane

Example Input: Relative expression of cholesterol transport-related proteins and inflammation markers through the induction of 7-ketosterol-mediated stress in Caco-2 cells.
Example Output: cholesterol

Example Input: Site dependent intestinal absorption of darunavir and its interaction with ketoconazole.
Example Output:
darunavir