[{"from": "human", "value": "Describe this molecule. [C][C][Branch1][C][C][C][C@@H1][Branch2][Ring1][C][C][=Branch1][C][=O][N][C@@H1][Branch1][Branch1][C][C][S][C][C][=Branch1][C][=O][N][NH3+1]"}, {"from": "gpt", "value": "The molecule is a peptide cation that is the conjugate acid of L-Leu-L-Met-NH2, arising from the protonation of the N-terminal amino group. Major species at pH 7.3. It is a conjugate acid of a L-Leu-L-Met-NH2."}]