You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
Suppose there is a molecule that meets the following description: The molecule is a muscarinic antagonist and belongs to the beta2 agonist class of molecules. Please write the SMILES representation of it.
user
O=C(O)N(C(c1ccccc1)c1cccc(OCc2cccc(CNCC(O)c3ccc(O)c4[nH]c(=O)ccc34)c2)c1)C1CN2CCC1CC2
assistant