[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. The molecule is a guanidinium ion that is the conjugate acid of L-homoarginine; major species at pH 7.3. It is a conjugate acid of a L-homoarginine."}, {"from": "gpt", "value": "[C][Branch1][=Branch2][C][C][NH1+1][=C][Branch1][C][N][N][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}]