[{"from": "human", "value": "Describe this molecule. [C][Branch1][#Branch2][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O][N][S][C][C][=Branch1][C][=O][O]"}, {"from": "gpt", "value": "The molecule is an L-cysteine thioether that is L-cysteine in which the hydrogen of the thiol group has been replaced by a carboxymethyl group. It has a role as a mucolytic. It is a L-cysteine thioether and a non-proteinogenic L-alpha-amino acid. It is a conjugate acid of a S-carboxylatomethyl-L-cysteine(1-)."}]