{
  "meta": {
    "disclaimer": "Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated. We may limit or otherwise restrict your access to the API in line with our Terms of Service.",
    "terms": "https://open.fda.gov/terms/",
    "license": "https://open.fda.gov/license/",
    "last_updated": "2025-09-19",
    "results": {
      "skip": 0,
      "limit": 1,
      "total": 1
    }
  },
  "results": [
    {
      "codes": [
        {
          "uuid": "6a1a5197-6845-4e6c-8651-5b84bc2fed4e",
          "code": "591-11-7",
          "type": "PRIMARY",
          "url": "https://commonchemistry.cas.org/detail?cas_rn=591-11-7",
          "code_system": "CAS",
          "references": [
            "1ba1230f-17d2-43a8-8bf6-305b53103649",
            "5bb6263b-a7da-4735-a8f6-143e15bc310b"
          ]
        },
        {
          "uuid": "f6e2c60e-9b83-494b-a9de-d2b3456386e9",
          "code": "m1910",
          "comments": "Merck Index",
          "type": "PRIMARY",
          "url": "https://merckindex.rsc.org/monographs/m1910?q=authorize",
          "code_system": "MERCK INDEX",
          "references": [
            "1ba1230f-17d2-43a8-8bf6-305b53103649"
          ]
        },
        {
          "uuid": "d382d918-f29a-4cf6-a90c-b1cb559e2935",
          "code": "209-700-2",
          "type": "PRIMARY",
          "url": "https://echa.europa.eu/substance-information/-/substanceinfo/100.008.820",
          "code_system": "ECHA (EC/EINECS)",
          "references": [
            "1ba1230f-17d2-43a8-8bf6-305b53103649"
          ]
        },
        {
          "uuid": "197189fb-a607-43d5-8e07-e476e9516802",
          "code": "11558",
          "type": "PRIMARY",
          "url": "https://pubchem.ncbi.nlm.nih.gov/compound/11558",
          "code_system": "PUBCHEM",
          "references": [
            "1ba1230f-17d2-43a8-8bf6-305b53103649"
          ]
        },
        {
          "uuid": "3f5bf099-3d26-4d7d-af84-6aa879ab8c98",
          "code": "1AX0NCS144",
          "type": "PRIMARY",
          "code_system": "FDA UNII"
        },
        {
          "uuid": "bc6a3383-6218-24a5-ffb6-deae1843c467",
          "code": "36436",
          "type": "PRIMARY",
          "url": "https://www.ebi.ac.uk/chebi/chebiOntology.do?chebiId=CHEBI:36436",
          "code_system": "CHEBI",
          "references": [
            "48511a68-357f-1dfc-09a7-b5abe266de40"
          ]
        },
        {
          "uuid": "0fc09794-4351-320b-bf19-b0efd729ab35",
          "code": "DTXSID901014526",
          "type": "PRIMARY",
          "url": "https://comptox.epa.gov/dashboard/chemical/details/DTXSID901014526",
          "code_system": "EPA CompTox",
          "references": [
            "48511a68-357f-1dfc-09a7-b5abe266de40"
          ]
        },
        {
          "uuid": "e5d8501a-f43e-db11-abf2-6d3ac0e9e86e",
          "code": "655",
          "type": "PRIMARY",
          "url": "https://dtp.cancer.gov/dtpstandard/servlet/dwindex?searchtype=NSC&outputformat=html&searchlist=655",
          "code_system": "NSC",
          "references": [
            "a77e1496-5a33-ed0c-3ae7-1df32057a66d"
          ]
        }
      ],
      "relationships": [
        {
          "uuid": "68cc1b66-4a48-45c6-86ca-a5315e006c24",
          "amount": {
            "uuid": "22316a08-9b9f-4b8e-bd39-b5ec3f250616"
          },
          "type": "ENANTIOMER->RACEMATE",
          "references": [
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "related_substance": {
            "uuid": "8395fb97-ae92-400a-a749-7d79fb479e76",
            "refuuid": "1f4f0443-8cf3-405d-9487-61367e1f3f9d",
            "name": "(5S)-5-Methyl-2(5H)-furanone",
            "unii": "ZA9THM6FSR",
            "linking_id": "ZA9THM6FSR",
            "ref_pname": "(5S)-5-Methyl-2(5H)-furanone",
            "substance_class": "reference"
          }
        },
        {
          "uuid": "34dcc413-6bd5-451b-8540-1793c4976f52",
          "amount": {
            "uuid": "5398f645-1dac-4e05-a0bb-37e559db2eb8"
          },
          "type": "ENANTIOMER->RACEMATE",
          "references": [
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "related_substance": {
            "uuid": "b4d92c0c-ed38-4175-b7a3-503f92d3ae5b",
            "refuuid": "9c1948ef-aadd-43d3-8756-714668133bb8",
            "name": "(5R)-5-Methyl-2(5H)-furanone",
            "unii": "S582FW9RL3",
            "linking_id": "S582FW9RL3",
            "ref_pname": "(5R)-5-Methyl-2(5H)-furanone",
            "substance_class": "reference"
          }
        }
      ],
      "substance_class": "chemical",
      "names": [
        {
          "uuid": "f28b0af9-bc89-4009-8fd6-24097c2a5421",
          "name": ".ALPHA.,.BETA.-ANGELICA LACTONE",
          "stdName": ".ALPHA.,.BETA.-ANGELICA LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "1914fc78-611d-48a3-8190-96286403318c",
          "name": ".BETA.-ANGELICA LACTONE",
          "stdName": ".BETA.-ANGELICA LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "ebe0f5b9-f10e-46b1-9d07-47155aebb82f",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "6a29f9d0-3949-4da0-b945-a362db1701d2",
          "name": ".DELTA.1-ANGELICA LACTONE",
          "stdName": ".DELTA.1-ANGELICA LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "99786fdb-626c-4f21-86c1-c574f3d2bbf0",
          "name": ".GAMMA.-METHYL-.DELTA..ALPHA.,.BETA.-BUTENOLIDE",
          "stdName": ".GAMMA.-METHYL-.DELTA..ALPHA.,.BETA.-BUTENOLIDE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "1017e672-21b3-481f-bd6b-1168ee26407f",
          "name": "2(5H)-FURANONE, 5-METHYL-",
          "stdName": "2(5H)-FURANONE, 5-METHYL-",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "5f112ca0-8436-42d6-89f1-6eb2f6c40f3c",
          "name": "2-OXO-5-METHYL-2,5-DIHYDROFURAN",
          "stdName": "2-OXO-5-METHYL-2,5-DIHYDROFURAN",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "4133b589-cb1f-4606-a433-7091ddec3c30",
          "name": "2-PENTEN-4-OLIDE",
          "stdName": "2-PENTEN-4-OLIDE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "af769a84-198f-4e42-bacb-cf6e37f57990",
          "name": "2-PENTENOIC ACID, 4-HYDROXY-, .GAMMA.-LACTONE",
          "stdName": "2-PENTENOIC ACID, 4-HYDROXY-, .GAMMA.-LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "eec78d93-078e-47a8-b1e9-374c74d8a716",
          "name": "4-HYDROXY-2-PENTENOIC ACID .GAMMA.-LACTONE",
          "stdName": "4-HYDROXY-2-PENTENOIC ACID .GAMMA.-LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "a8abd21b-3056-442a-9bb9-9bcdf94a10ba",
          "name": "4-HYDROXY-2-PENTENOIC ACID GAMMA-LACTONE",
          "stdName": "4-HYDROXY-2-PENTENOIC ACID GAMMA-LACTONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "006f049e-6b6d-4741-99ce-08da64e3e58a",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "28fd3d55-2acc-4f1e-b298-a916ba6ad8ec",
          "name": "4-METHYL-2-BUTEN-4-OLIDE",
          "stdName": "4-METHYL-2-BUTEN-4-OLIDE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "c507ed57-8a8c-4172-8e52-9a74a20759c3",
          "name": "5-Methyl-2(5H)-furanone",
          "stdName": "5-METHYL-2(5H)-FURANONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": true
        },
        {
          "uuid": "2d31d506-b00c-4237-ae00-87e91e0f3e76",
          "name": "ANGELICA LACTONE .BETA.-FORM [MI]",
          "stdName": "ANGELICA LACTONE .BETA.-FORM [MI]",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "91604bf9-2366-46a5-b9bf-f454702cffe4",
            "aa83240e-43c3-4de3-91a9-e0fd9718ae1a"
          ],
          "display_name": false
        },
        {
          "uuid": "a98c53b0-4dca-4bca-9383-0f7d48be29eb",
          "name": "FEMA NO. 4438",
          "stdName": "FEMA NO. 4438",
          "type": "cd",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "315c0b1e-2a33-4226-94da-1901026fca00",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        },
        {
          "uuid": "b9947496-32d9-47ea-a46d-bd4cc8b3ed40",
          "name": "NSC-655",
          "stdName": "NSC-655",
          "type": "cd",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "bba86007-8ce6-4ef7-81b6-656909c15f03",
            "91604bf9-2366-46a5-b9bf-f454702cffe4"
          ],
          "display_name": false
        }
      ],
      "references": [
        {
          "uuid": "bba86007-8ce6-4ef7-81b6-656909c15f03",
          "citation": "STN",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE",
            "AUTO_SELECTED"
          ]
        },
        {
          "uuid": "91604bf9-2366-46a5-b9bf-f454702cffe4",
          "citation": "STN (SCIFINDER)",
          "doc_type": "STN (SCIFINDER)",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "ebe0f5b9-f10e-46b1-9d07-47155aebb82f",
          "citation": "MERCK",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "315c0b1e-2a33-4226-94da-1901026fca00",
          "citation": "http://www.thegoodscentscompany.com/data/rw1386791.html",
          "url": "http://www.thegoodscentscompany.com/data/rw1386791.html",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "aa83240e-43c3-4de3-91a9-e0fd9718ae1a",
          "citation": "MERCK INDEX",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "006f049e-6b6d-4741-99ce-08da64e3e58a",
          "citation": "CFSAN",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "1ba1230f-17d2-43a8-8bf6-305b53103649",
          "citation": "SRS CODE IMPORT",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493391402000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "ca505883-87a9-49e6-84c9-5a948c7bd757",
          "citation": "SRS import [1AX0NCS144]",
          "url": "http://fdasis.nlm.nih.gov/srs/srsdirect.jsp?regno=1AX0NCS144",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493391402000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "5bb6263b-a7da-4735-a8f6-143e15bc310b",
          "citation": "STN",
          "doc_type": "STN (SCIFINDER)",
          "public_domain": true
        },
        {
          "uuid": "48511a68-357f-1dfc-09a7-b5abe266de40",
          "doc_type": "SYSTEM",
          "public_domain": true
        },
        {
          "uuid": "a77e1496-5a33-ed0c-3ae7-1df32057a66d",
          "citation": "NCI",
          "doc_type": "NCI DRUG DICTIONARY",
          "public_domain": true
        }
      ],
      "definition_type": "PRIMARY",
      "moieties": [
        {
          "uuid": "7020ec31-fcc2-415e-b3cc-13d4541c11da",
          "id": "7020ec31-fcc2-415e-b3cc-13d4541c11da",
          "molfile": "\n  CDK     10232410282D\n\n  7  7  0  0  0  0  0  0  0  0999 V2000\n   21.7814   -8.4573    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n   23.7538   -6.4997    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   23.2887   -7.9847    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   27.2939   -8.3785    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   25.3138   -6.4997    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   24.5415   -8.8923    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n   25.8125   -7.9549    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n  3  2  1  0  0  0  0\n  3  1  2  0  0  0  0\n  5  2  2  0  0  0  0\n  6  3  1  0  0  0  0\n  7  4  1  0  0  0  0\n  7  5  1  0  0  0  0\n  7  6  1  0  0  0  0\nM  END",
          "smiles": "CC1C=CC(=O)O1",
          "formula": "C5H6O2",
          "atropisomerism": "No",
          "charge": 0,
          "count": 1,
          "stereochemistry": "RACEMIC",
          "count_amount": {
            "type": "MOL RATIO",
            "average": 1,
            "units": "MOL RATIO",
            "uuid": "8dcc41de-0a5a-42dc-95a0-df3cddb87421"
          },
          "defined_stereo": 0,
          "ez_centers": 0,
          "molecular_weight": "98.1001",
          "optical_activity": "( + / - )",
          "stereo_centers": 1
        }
      ],
      "definition_level": "COMPLETE",
      "uuid": "ed38bdfa-90f1-48c0-b4d6-0a32361c7250",
      "version": "8",
      "structure": {
        "id": "4ace2c6d-dd84-4695-80ae-3e1d6491fa5f",
        "molfile": "\n   JSDraw210232410282D\n\n  7  7  0  0  0  0              0 V2000\n   27.3003   -7.1618    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n   25.3278   -9.1194    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   25.7929   -7.6345    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   21.7877   -7.2407    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   23.7678   -9.1194    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n   24.5401   -6.7269    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n   23.2691   -7.6643    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n  3  2  1  0  0  0  0\n  3  1  2  0  0  0  0\n  5  2  2  0  0  0  0\n  6  3  1  0  0  0  0\n  7  4  1  0  0  0  0\n  7  5  1  0  0  0  0\n  7  6  1  0  0  0  0\nM  END",
        "smiles": "CC1C=CC(=O)O1",
        "formula": "C5H6O2",
        "atropisomerism": "No",
        "charge": 0,
        "count": 1,
        "stereochemistry": "RACEMIC",
        "defined_stereo": 0,
        "ez_centers": 0,
        "molecular_weight": "98.1001",
        "optical_activity": "( + / - )",
        "references": [
          "bba86007-8ce6-4ef7-81b6-656909c15f03",
          "ca505883-87a9-49e6-84c9-5a948c7bd757"
        ],
        "stereo_centers": 1
      },
      "unii": "1AX0NCS144"
    }
  ]
}