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Chemical substance record

Mercaptopurine

50-44-2C5H4N4S152.182 g/mol

A member of the class of purines that is 6,7-dihydro-1H-purine carrying a thione group at position 6. An adenine analogue, it is used in the treatment of acute lymphocytic leukemia (ALL), chronic myeloid leukemia (CML), Crohn's disease, and ulcerative colitis. — ChEBI

Safety references

Safety documents & references

1 indexed references
JP · NITE

Government GHS classification

22A4116 · FY2010

View classification

Find 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 number50-44-2ChEBI ↗
Molecular formulaC5H4N4SChEBI ↗
Molar mass152.182 g/molChEBI ↗
Monoisotopic mass152.01567 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:50667ChEBI ↗

Cross-source molecular data

PubChem
Molar mass152.18 g/molPubChem ↗
Exact mass152.01566732 DaPubChem ↗
Computed XLogP0PubChem ↗
Topological polar surface area (Ų)85.2PubChem ↗
H-bond donors2PubChem ↗
H-bond acceptors2PubChem ↗
Rotatable bonds0PubChem ↗

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 identifier
mercaptopurine
1,7-dihydro-6H-purine-6-thione
GLVAUDGFNGKCSF-UHFFFAOYSA-N
S=c1ncnc2ncnc12
InChI=1S/C5H4N4S/c10-5-3-4(7-1-6-3)8-2-9-5/h1-2H,(H2,6,7,8,9,10)

Names & synonyms

1,7-dihydro-6H-purine-6-thioneMercaptopurinamercaptopurinumPuri-NetholPurinethol

Names are supplied by ChEBI. Trade names and related synonyms may describe a broader product context.

Classification & relationships

ChEBI ontology

Roles recorded in ChEBI

anticoronaviral agentantimetaboliteantineoplastic agent

Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.

Safety classification · Japan

NITE / Japanese government
Japan · FY2010 source classification
6-Mercaptopurine · 22A4116
EndpointReported classification
Acute toxicity (Oral)Category 3
Germ cell mutagenicityCategory 1B
Reproductive toxicityCategory 1B
Specific target organ toxicity - Single exposureCategory 1 (bone marrow, liver, small intestine)
Specific target organ toxicity - Repeated exposureCategory 1 (hematopoietic system, liver)
Hazardous to the aquatic environment (Acute)Category 3

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 classification

Mass ↔ amount of substance

Calculated from sourced mass
Equivalent amount
0.00657108 mol

Uses 152.182 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
C
Carbon · 5 atoms
39.46%
N
Nitrogen · 4 atoms
36.82%
S
Sulfur · 1 atom
21.07%
H
Hydrogen · 4 atoms
2.65%

Calculated 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 associations
The thiopurines: an update. ↗Investigational new drugs · 2005 Dec · PMID 16267626
US2697709 · Patent reference ↗Patent cross-reference supplied by ChEBI. Association alone does not establish claim scope.
US2721866 · Patent reference ↗Patent cross-reference supplied by ChEBI. Association alone does not establish claim scope.

Sources & record history

Checked 27 Sep 2026
EMBL-EBI ChEBI · CHEBI:50667

Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0

NCBI PubChem · CID 667490 · retrieved 2026-09-27

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.