Database / Pharmaceutical impurity
Pharmaceutical impurityTemozolomide EP Impurity E
Temozolomide EP Impurity E is listed in the pharmaceutical impurity collection. Its represented structure has formula C4H3N5O and a calculated molecular weight of 137.10 g/mol.
2D chemical structure
Chemical identity
- Catalog name
- Temozolomide EP Impurity E
- Common name
- Temozolomide EP Impurity E
- Chemical name
- 3,5-dihydroimidazo[4,5-d]triazin-4-one
- CAS
- Not available
- SMILES
- O=c1[nH]nnc2nc[nH]c12
- InChI
- InChI=1S/C4H3N5O/c10-4-2-3(6-1-5-2)7-9-8-4/h1H,(H2,5,6,7,8,10)
- InChIKey
- BTERLCQQBYXVIN-UHFFFAOYSA-N
- Associated API
- Temozolomide
Record ID: Adb4dbbe4c251
Computed properties
C4H3N5O Molecular formula
137.102 g/molMolecular weight
137.0338 DaMonoisotopic exact mass
87.32 ŲTopological polar surface area
-0.9588 Calculated LogP (Wildman–Crippen)
32.3044 cm³/molMolar refractivity (Wildman–Crippen)
4 countHydrogen-bond acceptors
2 countHydrogen-bond donors
Descriptors are calculated from the displayed SMILES. Calculated LogP is not a measured partition coefficient or a pH-specific LogD.
Molecular descriptor profile
Structural feature counts
Element composition
Radar scale: 0–100 percentile within 25,771 distinct represented structures in this release, using the midpoint rank for ties. Larger values indicate a higher descriptor rank, not greater safety or toxicity. Element counts include hydrogen and combine isotopes under each element.
Radar values and percentile reference
| Descriptor | Value | Percentile |
|---|---|---|
| Molecular weight | 137.102 | 3.97 |
| Calculated LogP (Wildman–Crippen) | -0.9588 | 7.79 |
| Topological polar surface area | 87.32 | 63.60 |
| Hydrogen-bond acceptors | 4 | 50.68 |
| Hydrogen-bond donors | 2 | 64.87 |
| Rotatable bonds (strict) | 0 | 3.45 |
Complete molecular descriptors
| Property | Calculated value | Unit / type |
|---|---|---|
| Molecular formula | C4H3N5O | dimensionless |
| Molecular weight | 137.102 | g/mol |
| Monoisotopic exact mass | 137.0338 | Da |
| Topological polar surface area | 87.32 | Ų |
| Calculated LogP (Wildman–Crippen) | -0.9588 | dimensionless |
| Molar refractivity (Wildman–Crippen) | 32.3044 | cm³/mol |
| Hydrogen-bond acceptors | 4 | count |
| Hydrogen-bond donors | 2 | count |
| Rotatable bonds (strict) | 0 | count |
| Heavy atoms | 10 | count |
| Heteroatoms | 6 | count |
| Rings | 2 | count |
| Aromatic rings | 2 | count |
| Aliphatic rings | 0 | count |
| Saturated rings | 0 | count |
| Aromatic heterocycles | 2 | count |
| Aliphatic heterocycles | 0 | count |
| Saturated heterocycles | 0 | count |
| Aromatic carbocycles | 0 | count |
| Aliphatic carbocycles | 0 | count |
| Fraction of sp³ carbon atoms | 0 | fraction |
| Formal charge | 0 | e |
| Disconnected components | 1 | count |
| Isotopically specified atoms | 0 | count |
| Potential atom stereocenters | 0 | count |
| Unspecified atom stereocenters | 0 | count |
| Spiro atoms | 0 | count |
| Bridgehead atoms | 0 | count |
| Labute approximate surface area | 54.2992 | Ų |
| Valence electrons | 50 | count |
| Radical electrons | 0 | count |
| Bertz complexity | 400.9402 | index |
| Balaban J | 3.0929 | index |
Ring categories overlap and should not be summed. No toxicity result, PDE, HBEL or acceptable intake is inferred from these descriptors.
Toxicological services and resources for Temozolomide EP Impurity E
Qualification and safety assessment of Temozolomide EP Impurity E
Explore toxicological qualification of Temozolomide EP Impurity E and ICH M7 mutagenic impurity assessment of Temozolomide EP Impurity E for evaluation of this impurity in its pharmaceutical context.
Where data gaps need to be addressed, resources include read-across assessment for Temozolomide EP Impurity E and acceptable intake and limit justification for Temozolomide EP Impurity E. The relevant approach depends on the available evidence, exposure and duration of use.
Related Altox services and technical resources
- ICH M7 Mutagenic Impurity Assessment
- Genotoxic Impurity Risk Assessment
- (Q)SAR Mutagenicity Assessment
- Mutagenic and Non-Mutagenic Impurity Assessment
- Toxicological Qualification of Impurities and Degradation Products
- Toxicological Read-Across Assessment
- Impurity Specification Setting and Limit Justification
- Acceptable Intake (AI) Assessment and Limit Derivation
Other catalogue designations with the same represented structure
These are separate catalogue entries; shared structure does not establish interchangeable pharmacopoeial designations.
Identity sources and calculation method
Identifiers originate from the source catalogues and available public identity records. InChI and InChIKey on this page are generated from the displayed SMILES. RDKit validation checks the molecular representation; it does not independently verify every catalogue assignment.
Discuss an assessment for Temozolomide EP Impurity E
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