Registration Dossier
Registration Dossier
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EC number: 217-968-7 | CAS number: 2022-85-7
Dissociation constant
Administrative data
- Endpoint:
- dissociation constant
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2004-06-07 - 2004-07-19
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 004
- Report date:
- 2005
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 112 (Dissociation Constants in Water)
- Version / remarks:
- 12 May 1981.
- GLP compliance:
- yes (incl. QA statement)
Test material
- Reference substance name:
- Flucytosine
- EC Number:
- 217-968-7
- EC Name:
- Flucytosine
- Cas Number:
- 2022-85-7
- Molecular formula:
- C4H4FN3O
- IUPAC Name:
- flucytosine
- Test material form:
- solid: particulate/powder
Constituent 1
- Specific details on test material used for the study:
- please refer to Test material information
Results and discussion
- Dissociating properties:
- yes
Dissociation constantopen allclose all
- No.:
- #1
- pKa:
- 2.74
- Temp.:
- 21.4 °C
- Remarks on result:
- other: Mean pKa (basic group)
- No.:
- #2
- pKa:
- 10.71
- Temp.:
- 21.4 °C
- Remarks on result:
- other: Mean pKa (acidic group)
Any other information on results incl. tables
Results
Preliminary test
Preliminary testing indicated that the basic pKa was approximately 2.85 and the acidic pKa was approximately 10.86.
Definitive test; basic pKa
The overall results are shown in the following table:
Determination |
pKa (basic) |
Mean pKa (basic) |
A |
2.72 |
see below |
B |
2.74 |
2.74 |
C |
2.76 |
see above |
Overall temperature: 21.4 ± 0.5ºC
Definitive test; acidic pKa
The overall results are shown in the following table:
Determination |
pKa |
Mean pKa |
A |
10.71 |
see below |
B |
10.73 |
10.71 |
C |
10.69 |
see above |
Overall temperature: 21.4 ± 0.5ºC
Applicant's summary and conclusion
- Conclusions:
- The dissociation constants of the test material have been determined to be 2.74 (basic group) and 10.71 (acidic group) at 21.4 ± 0.5ºC.
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