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.

Input: Consider Input: Management of psoriasis: the position of retinoid drugs.

Output: retinoid


Input: Consider Input: Sunitinib, sorafenib and mTOR inhibitors in renal cancer.

Output: sorafenib


Input: Consider Input: Selective inhibition of cyclooxygenase 2 spares renal function and prostaglandin synthesis in cirrhotic rats with ascites.


Output: prostaglandin