(R*,R*)-1,4-dimercaptobutane-2,3-diol

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 February 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Version / remarks:

2004

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

Version / remarks:

Commission Regulation (EC) No 440/2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

(R*,R*)-1,4-dimercaptobutane-2,3-diol

EC Number:

222-468-7

EC Name:

(R*,R*)-1,4-dimercaptobutane-2,3-diol

Cas Number:

3483-12-3

Molecular formula:

C4H10O2S2

IUPAC Name:

1,4-disulfanylbutane-2,3-diol

Specific details on test material used for the study:

Batch no. 44606300 / 50774
Test item storage 2–8 °C, under nitrogen

Study design

Analytical method:

high-performance liquid chromatography

Results and discussion

Partition coefficient

Key result

Type:

log Pow

Partition coefficient:

0.07

Temp.:

25 °C

pH:

5

Remarks on result:

other:

Remarks:

calculated as the mean of two determinations

Details on results:

Theoretical value of the log Pow
The log Pow value of the non-ionised test item species was calculated to be -0.28 (https://chemicalize.com/#/calculation).

HPLC method:

The dead time was determined to be 1.336 min.

Two determinations of the log Pow value of the test item were conducted by injecting a mixed solution of all reference items as well as the single test item solution twice using a phosphate buffered system at pH 5.0.
The retention time of 1,4-Dithiothreitol was 1.537 min in both runs, the single injection run (injecting test item and each reference substance separately) and in the mixed injection run (injecting test item and all reference items together).
The log Pow value for 1,4-Dithiothreitol was determined to be 0.07 (95% confidence interval: -0.34 - 0.48) in the first and the second injection.
Consequently, the log Pow value of 1,4-Dithiothreitol (CAS no. 3483-12-3) at pH 5.0 and 25 °C, calculated as the mean of both determinations, is 0.07.

Any other information on results incl. tables

Regression for the determination of the log POW value of 1,4-Dithiothreitol with the first injection

Plot log Pow vs log k:

Coefficient of regression (r2)	0.974
Intercept (A)	1.836
Slope (B)	2.15
log Pow	0.07
95% confidence interval for log Pow	-0.34 - 0.48

Regression for the determination of the log POW value of 1,4-Dithiothreitol with the second injection

Coefficient of regression (r2)	0.974
Intercept (A)	1.836
Slope (B)	2.15
log Pow	0.07
95% confidence interval for log Pow	-0.34 - 0.48

Applicant's summary and conclusion

Conclusions:

The HPLC method was applied for the determination of the log Pow of 1,4-Dithiothreitol. The log Pow value for 1,4-Dithiothreitol was determined to be 0.07 (95% confidence interval: -0.34 - 0.48) in the first and the second injection.
Consequently, the log Pow value of 1,4-Dithiothreitol at pH 5.0 and 25 °C is 0.07.

Executive summary:

The partition coefficient between octanol and water (Pow) of 1,4-Dithiothreitol (CAS no. 3483-12-3) was determined according to the OECD guideline 117. This determination is based upon a regression analysis of the log POW values of reference items against their respective retention times as determined by HPLC analysis.

The following reference items were used: Caffeine, 4-Acetylpyridine, Acetanilide, Acetophenone, Methyl benzoate, Benzophenone and Benzyl benzoate. The dead time of the HPLC system was determined with Thiourea.

This set of reference items yielded a calibration with log Pow values ranging from -0.07 to 4.0 and retention times ranging from 1.463 to 11.287 minutes. The dead time of the HPLC system was 1.336 minutes.

Two determinations of the log Pow value of the test item were conducted using a phosphate buffered system at pH 5.0 by injecting a mixed solution of all reference items as well as the single test item.

The log Pow value for 1,4-Dithiothreitol was determined to be 0.07 (95% confidence interval: -0.34 - 0.48) in the first and the second injection.

Consequently, the log Pow value of 1,4-Dithiothreitol at pH 5.0 and 25 °C is 0.07.

The determination is valid since the values of log Pow derived from the two repeated measurements fall within ±0.1 log units.