{
  "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": "21c14f38-7bdf-46eb-ba03-69de31a57af6",
          "code": "21835-01-8",
          "type": "PRIMARY",
          "url": "https://commonchemistry.cas.org/detail?cas_rn=21835-01-8",
          "code_system": "CAS",
          "references": [
            "7bc07bc5-ce5b-427e-8b19-131273f3449a",
            "a07d85fc-95ae-4f5d-9c00-66ced75a0f0f"
          ]
        },
        {
          "uuid": "28180e63-bdc3-46d1-a02d-8f4eeab46a70",
          "code": "13494-08-1",
          "type": "ALTERNATIVE",
          "url": "https://commonchemistry.cas.org/detail?cas_rn=13494-08-1",
          "code_system": "CAS",
          "references": [
            "7bc07bc5-ce5b-427e-8b19-131273f3449a",
            "ecf0b88e-8071-4275-aa0a-19f582f190fc"
          ]
        },
        {
          "uuid": "6ff08cd4-ffcc-4af1-a5c5-224c91b388aa",
          "code": "244-606-5",
          "type": "PRIMARY",
          "url": "https://echa.europa.eu/substance-information/-/substanceinfo/100.040.536",
          "code_system": "ECHA (EC/EINECS)",
          "references": [
            "7bc07bc5-ce5b-427e-8b19-131273f3449a"
          ]
        },
        {
          "uuid": "43e5b1b8-97c9-40a5-b875-34a91c1d5ea9",
          "code": "236-812-9",
          "type": "ALTERNATIVE",
          "url": "https://echa.europa.eu/substance-information/-/substanceinfo/100.033.451",
          "code_system": "ECHA (EC/EINECS)",
          "references": [
            "7bc07bc5-ce5b-427e-8b19-131273f3449a"
          ]
        },
        {
          "uuid": "97030ce1-24df-4aa1-a178-645940c7ce00",
          "code": "62752",
          "type": "PRIMARY",
          "url": "https://pubchem.ncbi.nlm.nih.gov/compound/62752",
          "code_system": "PUBCHEM",
          "references": [
            "7bc07bc5-ce5b-427e-8b19-131273f3449a"
          ]
        },
        {
          "uuid": "3e5035d6-a125-47f5-df89-009f5dc3d043",
          "code": "DTXSID0044232",
          "type": "PRIMARY",
          "url": "https://comptox.epa.gov/dashboard/chemical/details/DTXSID0044232",
          "code_system": "EPA CompTox",
          "references": [
            "7c286591-8873-eb16-8183-420e399b89a6"
          ]
        },
        {
          "uuid": "ce4fe3ff-d857-4944-8944-29eb5df941b9",
          "code": "XH8EA788C9",
          "type": "PRIMARY",
          "code_system": "FDA UNII"
        },
        {
          "uuid": "67004ef2-441f-902a-d36d-2bde0d4dad40",
          "code": "429",
          "type": "PRIMARY",
          "url": "https://www.fao.org/food/food-safety-quality/scientific-advice/jecfa/jecfa-flav/details/en/c/429/",
          "code_system": "JECFA MONOGRAPH",
          "references": [
            "29bc6d06-2757-5829-44c2-5ed05a39db63"
          ]
        }
      ],
      "substance_class": "chemical",
      "names": [
        {
          "uuid": "d98205a8-7675-4ba2-b259-d616a6fb82c9",
          "name": "1,2-CYCLOPENTANEDIONE, 3-ETHYL-",
          "stdName": "1,2-CYCLOPENTANEDIONE, 3-ETHYL-",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": false
        },
        {
          "uuid": "72807259-feba-4db9-b668-fc3e605e4f99",
          "name": "2-CYCLOPENTEN-1-ONE, 3-ETHYL-2-HYDROXY-",
          "stdName": "2-CYCLOPENTEN-1-ONE, 3-ETHYL-2-HYDROXY-",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "2c3f7937-6401-4e9d-89ec-23dfde4b1b2f",
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0"
          ],
          "display_name": false
        },
        {
          "uuid": "fcb00186-6a84-4cf1-b2bf-13e57af2a315",
          "name": "2-HYDROXY-3-ETHYL-2-CYCLOPENTEN-1-ONE",
          "stdName": "2-HYDROXY-3-ETHYL-2-CYCLOPENTEN-1-ONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": false
        },
        {
          "uuid": "e3f45a83-cf89-45ed-9fb8-e3914372b78e",
          "name": "2-HYDROXY-3-ETHYL-2-CYCLOPENTENONE",
          "stdName": "2-HYDROXY-3-ETHYL-2-CYCLOPENTENONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": false
        },
        {
          "uuid": "66b03bca-9758-4938-b560-5ee5c70d6838",
          "name": "3-ETHYL-1,2-CYCLOPENTANEDIONE",
          "stdName": "3-ETHYL-1,2-CYCLOPENTANEDIONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": true
        },
        {
          "uuid": "06b9b7c6-4e7e-42c0-8a72-c93cd288f016",
          "name": "3-ETHYL-2-CYCLOPENTEN-2-OL-1-ONE",
          "stdName": "3-ETHYL-2-CYCLOPENTEN-2-OL-1-ONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": false
        },
        {
          "uuid": "b1e51798-2bcf-4d24-9222-5ebd6222a0c1",
          "name": "3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE",
          "stdName": "3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "2c3f7937-6401-4e9d-89ec-23dfde4b1b2f",
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "7a369c3e-7543-4fe3-85f4-58ec48530cce",
            "e3c37ca1-baf7-4344-a0e1-cfec83a74ebf"
          ],
          "display_name": false
        },
        {
          "uuid": "888e8d45-340d-4eed-b5db-150b5215c9a0",
          "name": "3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE [FHFI]",
          "stdName": "3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE [FHFI]",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "7a369c3e-7543-4fe3-85f4-58ec48530cce"
          ],
          "display_name": false
        },
        {
          "uuid": "f21a4416-fd79-45c3-bfca-d07056fc21f3",
          "name": "3-ETHYL-2-HYDROXYCYCLOPENT-2-EN-1-ONE",
          "stdName": "3-ETHYL-2-HYDROXYCYCLOPENT-2-EN-1-ONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "2c3f7937-6401-4e9d-89ec-23dfde4b1b2f",
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0"
          ],
          "display_name": false
        },
        {
          "uuid": "1e9dfa37-30d4-797e-bb73-27a61a3f082f",
          "name": "ETHYLCYCLOPENTENOLONE",
          "stdName": "ETHYLCYCLOPENTENOLONE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "b9b00b59-43a5-4a08-04b2-47987560a829",
            "6885efaa-fbe3-d8af-6698-f7794ac2ae8d"
          ],
          "display_name": false
        },
        {
          "uuid": "066a63b5-f25d-45e6-8ec3-e345fcf651d8",
          "name": "ETHYLCYCLOTENE",
          "stdName": "ETHYLCYCLOTENE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
            "80b54387-4824-4817-a5cf-c16e0eb34cd9"
          ],
          "display_name": false
        },
        {
          "uuid": "ea5b36d0-84ee-4380-92ed-91eb1386425b",
          "name": "FEMA NO. 3152",
          "stdName": "FEMA NO. 3152",
          "type": "cd",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "0e6259ae-b065-42c3-bf1b-49c592e97c04"
          ],
          "display_name": false
        }
      ],
      "references": [
        {
          "uuid": "0e6259ae-b065-42c3-bf1b-49c592e97c04",
          "citation": "CHEMID 2010",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE",
            "AUTO_SELECTED"
          ]
        },
        {
          "uuid": "2c3f7937-6401-4e9d-89ec-23dfde4b1b2f",
          "citation": "CHEMID",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "d7e2f268-5693-4391-a53d-28fc2f0d9db0",
          "citation": "CHEMID",
          "doc_type": "CHEMID",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "7a369c3e-7543-4fe3-85f4-58ec48530cce",
          "citation": "FHFI",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "80b54387-4824-4817-a5cf-c16e0eb34cd9",
          "citation": "STN",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "7bc07bc5-ce5b-427e-8b19-131273f3449a",
          "citation": "SRS CODE IMPORT",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493390933000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "2b4a08f3-db35-47d6-9bae-93aeb0af8020",
          "citation": "AN OVERVIEW OF THE EFFECTS OF TOBACCO INGREDIENTS ON SMOKE CHEMISTRY AND TOXICITY; FOOD AND CHEMICAL TOXICOLOGY; BAKER, RR; 42(SUPPL):53-83, 2004",
          "url": "http://www.sciencedirect.com/science/article/pii/S0278691504000043",
          "doc_type": "JOURNAL ARTICLE",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "ca3a1bc2-9af1-4fc6-8fb5-f230ed375064",
          "citation": "SRS import [XH8EA788C9]",
          "url": "http://fdasis.nlm.nih.gov/srs/srsdirect.jsp?regno=XH8EA788C9",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493390933000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "e3c37ca1-baf7-4344-a0e1-cfec83a74ebf",
          "citation": "3-ETHYL-2-HYDROXY-2-CYCLOPENTEN-1-ONE [FHFI]",
          "doc_type": "SRS_LOCATOR",
          "public_domain": true
        },
        {
          "uuid": "7c286591-8873-eb16-8183-420e399b89a6",
          "citation": "WEBSITE",
          "url": "https://comptox.epa.gov/dashboard/dsstoxdb/results?utf8=%E2%9C%93&search=21835-01-8",
          "doc_type": "WEBSITE",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE"
          ]
        },
        {
          "uuid": "6885efaa-fbe3-d8af-6698-f7794ac2ae8d",
          "citation": "SIGMA ALDRICH CATALOG",
          "url": "https://www.sigmaaldrich.com/catalog/product/aldrich/w315230?lang=en&region=US",
          "doc_type": "WEBSITE",
          "public_domain": true
        },
        {
          "uuid": "b9b00b59-43a5-4a08-04b2-47987560a829",
          "citation": "TKB",
          "doc_type": "TOBACCO KNOWLEDGE BASE",
          "public_domain": true
        },
        {
          "uuid": "ecf0b88e-8071-4275-aa0a-19f582f190fc",
          "citation": "STN",
          "doc_type": "STN (SCIFINDER)",
          "public_domain": true
        },
        {
          "uuid": "a07d85fc-95ae-4f5d-9c00-66ced75a0f0f",
          "citation": "STN",
          "doc_type": "STN (SCIFINDER)",
          "public_domain": true
        },
        {
          "uuid": "29bc6d06-2757-5829-44c2-5ed05a39db63",
          "citation": "JECFA",
          "doc_type": "JECFA",
          "public_domain": true
        }
      ],
      "definition_type": "PRIMARY",
      "moieties": [
        {
          "uuid": "c8b3c594-61e8-4d14-8f3b-5c0d3bdc0256",
          "id": "c8b3c594-61e8-4d14-8f3b-5c0d3bdc0256",
          "molfile": "\n  Marvin  01132110222D          \n\n  9  9  0  0  0  0            999 V2000\n    7.8292   -6.3617    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    7.0817   -6.5706    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.5029   -5.9842    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.7564   -5.1994    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    7.5527   -4.9745    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    6.0880   -4.7094    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.0880   -3.8835    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    5.4188   -5.1994    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    5.6733   -5.9842    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n  2  1  1  0  0  0  0\n  3  2  1  0  0  0  0\n  3  4  2  0  0  0  0\n  3  9  1  0  0  0  0\n  4  5  1  0  0  0  0\n  4  6  1  0  0  0  0\n  6  7  2  0  0  0  0\n  6  8  1  0  0  0  0\n  9  8  1  0  0  0  0\nM  END",
          "smiles": "CCC1=C(C(=O)CC1)O",
          "formula": "C7H10O2",
          "atropisomerism": "No",
          "charge": 0,
          "count": 1,
          "stereochemistry": "ACHIRAL",
          "count_amount": {
            "type": "MOL RATIO",
            "average": 1,
            "units": "MOL RATIO",
            "uuid": "051efd0f-60cf-424c-8a0c-8a11bfea86a6"
          },
          "defined_stereo": 0,
          "ez_centers": 0,
          "molecular_weight": "126.1534",
          "optical_activity": "NONE",
          "stereo_centers": 0
        }
      ],
      "definition_level": "COMPLETE",
      "uuid": "39f46033-a4bd-4fb9-8855-68700dab50da",
      "version": "5",
      "structure": {
        "id": "5b341a1a-86a3-42a4-b159-ee9d8d836ec9",
        "molfile": "\n  Marvin  01132104442D          \n\n  9  9  0  0  0  0            999 V2000\n    6.5029   -5.9842    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.7564   -5.1994    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.0880   -4.7094    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    6.0880   -3.8835    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    5.4188   -5.1994    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    5.6733   -5.9842    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    7.5527   -4.9745    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    7.0817   -6.5706    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    7.8292   -6.3617    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n  1  2  2  0  0  0  0\n  2  3  1  0  0  0  0\n  3  4  2  0  0  0  0\n  3  5  1  0  0  0  0\n  6  5  1  0  0  0  0\n  1  6  1  0  0  0  0\n  2  7  1  0  0  0  0\n  1  8  1  0  0  0  0\n  8  9  1  0  0  0  0\nM  END",
        "smiles": "CCC1=C(C(=O)CC1)O",
        "formula": "C7H10O2",
        "atropisomerism": "No",
        "charge": 0,
        "count": 1,
        "stereochemistry": "ACHIRAL",
        "defined_stereo": 0,
        "ez_centers": 0,
        "molecular_weight": "126.1534",
        "optical_activity": "NONE",
        "references": [
          "0e6259ae-b065-42c3-bf1b-49c592e97c04",
          "ca3a1bc2-9af1-4fc6-8fb5-f230ed375064"
        ],
        "stereo_centers": 0
      },
      "unii": "XH8EA788C9"
    }
  ]
}