You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
Generate a molecule that fulfills the requirement: The molecule is a endothelin antagonist.
user
Cc1sc(C(Cc2c[nH]c3ccccc23)N(C(=O)C(N)CC(C)C)C(=O)N2CCCCCC2)nc1C(=O)O
assistant