[{"from": "human", "value": "Describe this molecule. [C][C][S][C][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O][N]"}, {"from": "gpt", "value": "The molecule is an S-ethylhomocysteine that has S-configuration at the chiral centre. It has a role as an antimetabolite and a carcinogenic agent. It is an enantiomer of a D-ethionine."}]