{
  "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": "2026-09-09",
    "results": {
      "skip": 0,
      "limit": 1,
      "total": 1
    }
  },
  "results": [
    {
      "codes": [
        {
          "uuid": "f089fce5-69ee-44e4-b483-e0fc349d127b",
          "code": "108-31-6",
          "type": "PRIMARY",
          "url": "https://commonchemistry.cas.org/detail?cas_rn=108-31-6",
          "code_system": "CAS",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff",
            "d11b91b8-2c43-445a-98a8-13ad9885c82e"
          ]
        },
        {
          "uuid": "90768c4f-da15-4559-b373-2b491fada6b7",
          "code": "MALEIC ANHYDRIDE",
          "type": "PRIMARY",
          "url": "https://en.wikipedia.org/wiki/Maleic_anhydride",
          "code_system": "WIKIPEDIA",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "3dd600f2-6352-4bf3-a1c6-664a44bf705e",
          "code": "1362876",
          "comments": "RxNorm",
          "type": "PRIMARY",
          "url": "https://rxnav.nlm.nih.gov/REST/rxcui/1362876/allProperties.xml?prop=all",
          "code_system": "RXCUI",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "a71cfdc9-26ff-4996-82e4-98887bcc6dcd",
          "code": "m7038",
          "comments": "Merck Index",
          "type": "PRIMARY",
          "url": "https://merckindex.rsc.org/monographs/m7038?q=authorize",
          "code_system": "MERCK INDEX",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "431a2c75-fb13-4fa0-80d5-da9eda0e8619",
          "code": "SUB27466",
          "type": "PRIMARY",
          "code_system": "EVMPD",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "b6919d83-2a97-4493-a455-53fb73f78103",
          "code": "203-571-6",
          "type": "PRIMARY",
          "url": "https://echa.europa.eu/substance-information/-/substanceinfo/100.003.247",
          "code_system": "ECHA (EC/EINECS)",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "813e7e46-9974-42e6-9c07-b1e46b22b392",
          "code": "7923",
          "type": "PRIMARY",
          "url": "https://pubchem.ncbi.nlm.nih.gov/compound/7923",
          "code_system": "PUBCHEM",
          "references": [
            "442e21a8-19f1-43b5-8a4e-8923a63ea4ff"
          ]
        },
        {
          "uuid": "7844e2f6-ca41-e7a9-b740-44a209fe9885",
          "code": "183",
          "type": "PRIMARY",
          "url": "https://pubchem.ncbi.nlm.nih.gov/source/hsdb/183",
          "code_system": "HSDB",
          "references": [
            "5fe0b9b9-b260-c9fd-5cf5-e212ee2c091a"
          ]
        },
        {
          "uuid": "1640d647-b2fa-f9b1-9dfd-4ccada5c055c",
          "code": "DTXSID7024166",
          "type": "PRIMARY",
          "url": "https://comptox.epa.gov/dashboard/chemical/details/DTXSID7024166",
          "code_system": "EPA CompTox",
          "references": [
            "6465cd5d-e84f-8542-68bd-1d9abfa4316d"
          ]
        },
        {
          "uuid": "73e2441a-4d4d-43dc-8d16-3dd969f82d13",
          "code": "V5877ZJZ25",
          "type": "PRIMARY",
          "code_system": "FDA UNII"
        },
        {
          "uuid": "e1c45eae-136b-9d60-1eaa-45377c4300f4",
          "code": "474859",
          "type": "PRIMARY",
          "url": "https://www.ebi.ac.uk/chebi/chebiOntology.do?chebiId=CHEBI:474859",
          "code_system": "CHEBI",
          "references": [
            "b5133dc2-dd29-72e3-8839-cddd97557712"
          ]
        },
        {
          "uuid": "c73aa77b-d9ef-2e72-17f2-9cce701f0430",
          "code": "137651",
          "type": "PRIMARY",
          "url": "https://dtp.cancer.gov/dtpstandard/servlet/dwindex?searchtype=NSC&outputformat=html&searchlist=137651",
          "code_system": "NSC",
          "references": [
            "0709ee96-4213-dc44-1eb1-d2ea26918be4"
          ]
        },
        {
          "uuid": "65bc7693-b3ac-72e0-071a-682b76583827",
          "code": "100000091503",
          "type": "PRIMARY",
          "code_system": "SMS_ID",
          "references": [
            "9d1fc214-ed0f-c5bc-49cc-6927c8708f8c"
          ]
        },
        {
          "uuid": "3b27f699-2bcc-5bfd-7c68-a985fbdf80ad",
          "code": "V5877ZJZ25",
          "type": "PRIMARY",
          "url": "https://dailymed.nlm.nih.gov/dailymed/search.cfm?adv=1&query=V5877ZJZ25",
          "code_system": "DAILYMED",
          "references": [
            "bcf33d7b-a21f-8f69-4abe-f1d943421bca"
          ]
        }
      ],
      "substance_class": "chemical",
      "names": [
        {
          "uuid": "697a9b07-fab1-4cce-bf8a-d05ef171ea95",
          "name": "2,5-FURANDIONE",
          "stdName": "2,5-FURANDIONE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "767f68fd-778a-4bea-a80f-6e71a4fc52ed"
          ],
          "display_name": false
        },
        {
          "uuid": "b75d55c2-9c99-4cc0-a8fa-f9a616c06ccf",
          "name": "CIS-BUTENEDIOIC ANHYDRIDE",
          "stdName": "CIS-BUTENEDIOIC ANHYDRIDE",
          "type": "sys",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "767f68fd-778a-4bea-a80f-6e71a4fc52ed"
          ],
          "display_name": false
        },
        {
          "uuid": "dbe24bc5-aaae-4c00-8cff-330610bdf3e5",
          "name": "MALEIC ANHYDRIDE",
          "stdName": "MALEIC ANHYDRIDE",
          "type": "of",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "c8a247c7-55a8-48ab-861c-88357c66a531",
            "5af7defb-b3ad-454d-ba31-1f281d047e5d",
            "767f68fd-778a-4bea-a80f-6e71a4fc52ed",
            "6a2c4c74-0835-41ee-b97e-7f1b7629a93a",
            "b3073638-7d5a-4e83-a340-567feb9ccc7d",
            "d44af8ad-7485-4297-9851-d099802217af",
            "dc646cfc-524a-40de-aace-cc4e7b1db14f"
          ],
          "display_name": true,
          "domains": [
            "cosmetic"
          ],
          "name_orgs": [
            {
              "uuid": "5b40ef37-cebe-45e5-8ad4-22412c62c299",
              "name_org": "INCI"
            }
          ]
        },
        {
          "uuid": "af20bb6d-db7b-42a3-ac50-3b5d7f7eefe1",
          "name": "MALEIC ANHYDRIDE [HSDB]",
          "stdName": "MALEIC ANHYDRIDE [HSDB]",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "6a2c4c74-0835-41ee-b97e-7f1b7629a93a"
          ],
          "display_name": false
        },
        {
          "uuid": "29a0c667-e163-4bb7-93d9-a3e46fd4e8cb",
          "name": "MALEIC ANHYDRIDE [MI]",
          "stdName": "MALEIC ANHYDRIDE [MI]",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "b3073638-7d5a-4e83-a340-567feb9ccc7d"
          ],
          "display_name": false
        },
        {
          "uuid": "777f087e-642e-4f2d-89d0-c6344ed26644",
          "name": "NSC-137651",
          "stdName": "NSC-137651",
          "type": "cd",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "da6bcfed-3f4e-4961-b138-872180f0e9c5"
          ],
          "display_name": false
        },
        {
          "uuid": "b7fc2e1c-223a-432c-8d6e-a3fc8af66f84",
          "name": "TOXILIC ANHYDRIDE",
          "stdName": "TOXILIC ANHYDRIDE",
          "type": "cn",
          "languages": [
            "en"
          ],
          "preferred": false,
          "references": [
            "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
            "767f68fd-778a-4bea-a80f-6e71a4fc52ed"
          ],
          "display_name": false
        }
      ],
      "references": [
        {
          "uuid": "767f68fd-778a-4bea-a80f-6e71a4fc52ed",
          "citation": "MERCK",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE",
            "AUTO_SELECTED"
          ]
        },
        {
          "uuid": "59897cda-8e3f-48d3-8eb8-8ab7e58face7",
          "citation": "MERCK INDEX",
          "doc_type": "MERCK INDEX",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "b3073638-7d5a-4e83-a340-567feb9ccc7d",
          "citation": "MERCK INDEX",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "d44af8ad-7485-4297-9851-d099802217af",
          "citation": "PCPC",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "6a2c4c74-0835-41ee-b97e-7f1b7629a93a",
          "citation": "HSDB",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "da6bcfed-3f4e-4961-b138-872180f0e9c5",
          "citation": "CHEMID",
          "doc_type": "SRS",
          "public_domain": true,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "442e21a8-19f1-43b5-8a4e-8923a63ea4ff",
          "citation": "SRS CODE IMPORT",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493390758000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "11cb6722-dcf4-4a6f-98ed-b09f00fe4622",
          "citation": "SRS import [V5877ZJZ25]",
          "url": "http://fdasis.nlm.nih.gov/srs/srsdirect.jsp?regno=V5877ZJZ25",
          "doc_type": "SRS",
          "public_domain": true,
          "document_date": 1493390758000,
          "tags": [
            "NOMEN"
          ]
        },
        {
          "uuid": "c8a247c7-55a8-48ab-861c-88357c66a531",
          "citation": "MALEIC ANHYDRIDE [MI]",
          "doc_type": "SRS_LOCATOR",
          "public_domain": true
        },
        {
          "uuid": "dc646cfc-524a-40de-aace-cc4e7b1db14f",
          "citation": "MALEIC ANHYDRIDE [INCI]",
          "doc_type": "SRS_LOCATOR",
          "public_domain": true
        },
        {
          "uuid": "5af7defb-b3ad-454d-ba31-1f281d047e5d",
          "citation": "MALEIC ANHYDRIDE [HSDB]",
          "doc_type": "SRS_LOCATOR",
          "public_domain": true
        },
        {
          "uuid": "5fe0b9b9-b260-c9fd-5cf5-e212ee2c091a",
          "citation": "WEBSITE",
          "url": "https://toxnet.nlm.nih.gov/cgi-bin/sis/search2/r?dbs+hsdb:@term+@rn+@rel+108-31-6",
          "doc_type": "WEBSITE",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE"
          ]
        },
        {
          "uuid": "6465cd5d-e84f-8542-68bd-1d9abfa4316d",
          "citation": "WEBSITE",
          "url": "https://comptox.epa.gov/dashboard/dsstoxdb/results?utf8=%E2%9C%93&search=108-31-6",
          "doc_type": "WEBSITE",
          "public_domain": true,
          "tags": [
            "NOMEN",
            "PUBLIC_DOMAIN_RELEASE"
          ]
        },
        {
          "uuid": "d11b91b8-2c43-445a-98a8-13ad9885c82e",
          "citation": "STN",
          "doc_type": "STN (SCIFINDER)",
          "public_domain": true
        },
        {
          "uuid": "b5133dc2-dd29-72e3-8839-cddd97557712",
          "doc_type": "SYSTEM",
          "public_domain": true
        },
        {
          "uuid": "0709ee96-4213-dc44-1eb1-d2ea26918be4",
          "citation": "NCI",
          "doc_type": "NCI DRUG DICTIONARY",
          "public_domain": true
        },
        {
          "uuid": "bcf33d7b-a21f-8f69-4abe-f1d943421bca",
          "citation": "DailyMed",
          "doc_type": "DAILYMED",
          "public_domain": true
        },
        {
          "uuid": "9d1fc214-ed0f-c5bc-49cc-6927c8708f8c",
          "citation": "EU-SRS",
          "doc_type": "EMA LIST",
          "public_domain": true
        }
      ],
      "definition_type": "PRIMARY",
      "moieties": [
        {
          "uuid": "d02b7157-1ee6-45a1-ba13-587c2c72cd2c",
          "id": "d02b7157-1ee6-45a1-ba13-587c2c72cd2c",
          "molfile": "\n  Marvin  01132110462D          \n\n  7  7  0  0  0  0            999 V2000\n    1.8417   -1.8958    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    2.5583   -2.3083    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    3.2662   -1.8917    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    3.9824   -2.3083    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    4.6917   -1.8917    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    3.9824   -3.1333    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    2.5583   -3.1333    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n  2  1  2  0  0  0  0\n  3  2  1  0  0  0  0\n  2  7  1  0  0  0  0\n  4  3  1  0  0  0  0\n  4  5  2  0  0  0  0\n  6  4  1  0  0  0  0\n  7  6  2  0  0  0  0\nM  END",
          "smiles": "C1=CC(=O)OC1=O",
          "formula": "C4H2O3",
          "atropisomerism": "No",
          "charge": 0,
          "count": 1,
          "stereochemistry": "ACHIRAL",
          "count_amount": {
            "type": "MOL RATIO",
            "average": 1,
            "units": "MOL RATIO",
            "uuid": "bd31cae1-83d9-4b4b-91b6-c46adede369b"
          },
          "defined_stereo": 0,
          "ez_centers": 0,
          "molecular_weight": "98.057",
          "optical_activity": "NONE",
          "stereo_centers": 0
        }
      ],
      "definition_level": "COMPLETE",
      "uuid": "3f127dd1-8266-46c5-be70-92ae318363da",
      "version": "14",
      "structure": {
        "id": "fc19b27e-1dd3-40bd-8fc0-55952307fd96",
        "molfile": "\n  Marvin  01132113032D          \n\n  7  7  0  0  0  0            999 V2000\n    2.5583   -2.3083    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    2.5583   -3.1333    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    3.9824   -3.1333    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    3.9824   -2.3083    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0\n    3.2662   -1.8917    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    1.8417   -1.8958    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n    4.6917   -1.8917    0.0000 O   0  0  0  0  0  0  0  0  0  0  0  0\n  3  4  1  0  0  0  0\n  4  5  1  0  0  0  0\n  5  1  1  0  0  0  0\n  2  3  2  0  0  0  0\n  1  2  1  0  0  0  0\n  1  6  2  0  0  0  0\n  4  7  2  0  0  0  0\nM  END",
        "smiles": "C1=CC(=O)OC1=O",
        "formula": "C4H2O3",
        "atropisomerism": "No",
        "charge": 0,
        "count": 1,
        "stereochemistry": "ACHIRAL",
        "defined_stereo": 0,
        "ez_centers": 0,
        "molecular_weight": "98.057",
        "optical_activity": "NONE",
        "references": [
          "767f68fd-778a-4bea-a80f-6e71a4fc52ed",
          "11cb6722-dcf4-4a6f-98ed-b09f00fe4622"
        ],
        "stereo_centers": 0
      },
      "unii": "V5877ZJZ25"
    }
  ]
}