Chemical identity

Sildenafil EP Impurity C / O-Desethyl Sildenafil

CAS 139755-91-2 · C20H26N6O4S

01Identity

Identifiers and names for this exact compound. Empty fields are left unassigned.

Lazychem IDLC-28044
PubChem CID135565516
NameSildenafil EP Impurity C / O-Desethyl Sildenafil
CAS RN139755-91-2
Molecular formulaC20H26N6O4S
Molecular weight446.52
IUPAC name5-(2-Hydroxy-5-((4-methylpiperazin-1-yl)sulfonyl)phenyl)-1-methyl-3-propyl-1,6-dihydro-7H-pyrazolo(4,3-d)pyrimidin-7-one
InChIKeyLTNJUPYNXDNXBO-UHFFFAOYSA-N

02Structure identifiers

2D structurePubChem CID 135565516
Two-dimensional chemical structure of Sildenafil EP Impurity C / O-Desethyl Sildenafil, CAS 139755-91-2
Two-dimensional structure for the PubChem identity linked to this record. Confirm the identifiers before analytical use.

The parsed structure contains 4 rings, includes aromatic atoms, includes aliphatic carbon. These statements are calculated from the published structure string.

Defined stereocentres0
Unassigned stereocentres0
Ring count4
Secondary amines0
Tertiary amines1
N-methyl amine sites1
SMILESCCCC1=NN(C2=C1N=C(NC2=O)C3=C(C=CC(=C3)S(=O)(=O)N4CCN(CC4)C)O)C
InChINot listed
Formula from structureC20H26N6O4S
Molecular weight from structure446.52

03Possible N-nitroso structures

Shown for structural screening only. These candidates are not confirmed impurities, formation predictions or analytical findings.

Matched amine site1 candidate
Chemical structure of Sildenafil EP Impurity C / O-Desethyl Sildenafil with the matched amine site highlighted in amber
Amber identifies the screened atom and adjacent bonds.
Possible structure candidateUnverified identity
First calculated possible N-nitroso structure derived from Sildenafil EP Impurity C / O-Desethyl Sildenafil, with the new N-nitroso group highlighted in amber
The new N-N=O atoms and bonds are highlighted. No CAS number or compound name is assigned by this calculation.
Candidate 1Possible N-nitroso structural candidate
Calculated formula
C19H23N7O5S
Candidate SMILES
CCCc1nn(C)c2c(=O)[nH]c(-c3cc(S(=O)(=O)N4CCN(N=O)CC4)ccc3O)nc12

Interpretation: A structural alert alone does not establish that a nitrosamine forms. Evaluate nitrite sources, amine reagents, pH, temperature, process sequence, purge and analytical evidence.

04India status for this compound

These results apply only to this exact compound name and CAS number. Confirm the current official instruments before making a regulatory decision.

NDPS / RCSNO EXACT MATCH FOUNDCAS 139755-91-2 has no exact match in the reviewed published schedule.
SCOMETNO EXACT REVIEWED CAS MATCHCAS 139755-91-2 has no exact match in the reviewed SCOMET list.
Review date2026-08-01Recheck the current official instruments for the material, concentration, activity and date in question.

05Names and relationships

Associated parent compound

Sildenafil

View API and impurity family

Other names

  • Sildenafil EP Impurity C
  • O-Desethyl Sildenafil
  • 5-[2-hydroxy-5-(4-methylpiperazin-1-yl)sulfonylphenyl]-1-methyl-3-propyl-6H-pyrazolo[4,3-d]pyrimidin-7-one
  • 139755-91-2
  • Sildenafil Impurity C
  • UNII-2TEH1FB1FX
  • 2TEH1FB1FX
  • Sildenafil citrate impurity C [EP]
  • 5-(2-Hydroxy-5-((4-methylpiperazin-1-yl)sulfonyl)phenyl)-1-methyl-3-propyl-1,6-dihydro-7H-pyrazolo(4,3-d)pyrimidin-7-one
  • 7H-Pyrazolo(4,3-d)pyrimidin-7-one, 1,6-dihydro-5-(2-hydroxy-5-((4-methyl-1-piperazinyl)sulfonyl)phenyl)-1-methyl-3-propyl-
  • SILDENAFIL CITRATE IMPURITY C [EP IMPURITY]
  • RefChem:167181

Related records from the same parent family

06Documented history

Dated discovery, occurrence, use and issue claims are published only when a suitable primary or government source is available.

No dated history available

No verified discovery, first report, occurrence, use or issue event is currently available for this identity.

07Sources