[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is an L-alpha-amino acid zwitterion that is allin in which a proton has been transferred from the carboxy group to the amino group. It is the major species at pH 7.3. It has a role as an antimicrobial agent, an antioxidant, a cardioprotective agent, a neuroprotective agent and a plant metabolite. It is a tautomer of an alliin."}, {"from": "gpt", "value": "[C][=C][C][S@][=Branch1][C][=O][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}]