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SHEET /m/methotrexate · PubChem CID 126941 · CAS 59-05-2 · REV 2026.07

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Methotrexate

from source

C20H22N8O5 · 454.4 g/mol

amethopterin · MTX · Antifolan · Emtexate

What is Methotrexate?

A folate blocker used at low strength for rheumatoid arthritis and psoriasis and at high strength as a cancer medicine. from source

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Fig. 1 · 2D structure RDKit

SMILESCN(CC1=CN=C2C(=N1)C(=NC(=N2)N)N)C3=CC=C(C=C3)C(=O)N[C@@H](CCC(=O)O)C(=O)O

Where you'll find it

Dispensed on prescription, not sold on a shelf. See the rest of the prescription medicine group.

Relative acute toxicity from source

Animal study data · LD50

Reported LD50
43 mg/kg · highly toxic
Species
rat
Route
oral

An LD50 describes acute toxicity under experimental conditions and is not a safe or dangerous dose for a person.

Toxicity & hazards

Toxicity · LD50

43 mg/kg · highly toxic · LD50 rat oral from source

DangerToxicIrritantHealth hazardH301, H315, H319, H340, H360from source

Keep roaming

Where Methotrexate leads

Sources & methodology

PubChem CID
126941
Wikidata
Q422232
Structure
PubChem → RDKit
LD50
PubChem
Similar molecules
MoleculeFinder fingerprint similarity
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