Methoxsalen
A member of the class of psoralens that is 7H-furo[3,2-g]chromen-7-one in which the 9 position is substituted by a methoxy group. It is a constituent of the fruits of Ammi majus. Like other psoralens, trioxsalen causes photosensitization of the skin. It is administered topically or orally in conjunction with UV-A for phototherapy treatment of vitiligo and severe psoriasis. — ChEBI
Safety documents & references
1 indexed referencesFind a product-specific SDS
Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.
Identity & molecular properties
Source-linked values| CAS number | 298-81-7 | ChEBI ↗ |
| Molecular formula | C12H8O4 | ChEBI ↗ |
| Molar mass | 216.192 g/mol | ChEBI ↗ |
| Monoisotopic mass | 216.04226 Da | ChEBI ↗ |
| Formal charge | 0 | ChEBI ↗ |
| ChEBI identifier | CHEBI:18358 | ChEBI ↗ |
Cross-source molecular data
PubChem| Molar mass | 216.19 g/mol | PubChem ↗ |
| Exact mass | 216.04225873 Da | PubChem ↗ |
| Computed XLogP | 1.9 | PubChem ↗ |
| Topological polar surface area (Ų) | 48.7 | PubChem ↗ |
| H-bond donors | 0 | PubChem ↗ |
| H-bond acceptors | 4 | PubChem ↗ |
| Rotatable bonds | 1 | PubChem ↗ |
PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.
Names & structural identifiers
Copy any identifiermethoxsalen9-methoxy-7H-furo[3,2-g]chromen-7-oneQXKHYNVANLEOEG-UHFFFAOYSA-NCOc1c2occc2cc2ccc(=O)oc12InChI=1S/C12H8O4/c1-14-12-10-8(4-5-15-10)6-7-2-3-9(13)16-11(7)12/h2-6H,1H3Names & synonyms
Names are supplied by ChEBI. Trade names and related synonyms may describe a broader product context.
Classification & relationships
ChEBI ontologyRoles recorded in ChEBI
Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.
Safety classification · Japan
NITE / Japanese government9-Methoxy-7H-furo[3,2-g][1]benzopyran-7-one; Methoxsalen · R02-B-075-MHLW, MOE
| Endpoint | Reported classification |
|---|---|
| Acute toxicity （Oral） | Category 4 |
| Germ cell mutagenicity | Category 2 |
| Carcinogenicity | Category 1A |
| Reproductive toxicity | Category 1B |
| Specific target organ toxicity - Single exposure | Category 3 (Narcotic effects) |
| Specific target organ toxicity - Repeated exposure | Category 1 (thyroid, kidney) |
Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.
Read the original NITE classificationMass ↔ amount of substance
Calculated from sourced massUses 216.192 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.
Elemental composition
Theoretical mass fractionsCOHCalculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.
Research & patent references
Selected source associationsSources & record history
Checked 27 Sep 2026Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0
PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.