N-[2-(4-oxo-4H-3,1-benzoxazin-2-yl)phenyl]naphthalene-2-sulphonamide

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-04-10 to 2018-04-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2004

Deviations:

yes

Remarks:

standards were injected separately instead of simultaneously

Qualifier:

according to guideline

Guideline:

other: Council Regulation (EC) No. 266/2016, Method A.24

Version / remarks:

2016

Deviations:

yes

Remarks:

standards were injected separately instead of simultaneously

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2017-01-03

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Store in the original container. Store container tightly closed in a dry, cool, dark and well ventilated place.

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

4.65

Temp.:

24.8 °C

pH:

4

Type:

log Pow

Partition coefficient:

4.33

Temp.:

24.8 °C

pH:

7

Type:

log Pow

Partition coefficient:

2.66

Temp.:

25.4 °C

pH:

9

Details on results:

pH Values of the Buffer Solutions
pH Value 4 7 9
adjusted value 4.003 6.973 9.001
after analysis 4.005 6.816 8.832

Signal-to-Noise
The signal-to-noise ratio for the void time marker, reference items and the test item was > 3.

pH4
- Temperature [°C]: min. 24.8 / max. 25.0 / mean 24.8
- Void Time (t0) [min]: No.1: 0.420 / No.2: 0.418 / No.3: 0.419 / Mean: 0.419
- Calibration: The correlation coefficient r for the first and second calibration was > 0.9.

pH7
- Temperature [°C]: min. 24.7 / max. 24.8 / mean 24.8
- Void Time (t0) [min]: No.1: 0.417 / No.2: 0.419 / No.3: 0.417 / Mean: 0.418
- Calibration: The correlation coefficient r for the first and second calibration was > 0.9.

pH9
- Temperature [°C]: min. 25.2 / max. 25.5 / mean 25.4
- Void Time (t0) [min]: No.1: 0.433 / No.2: 0.431 / No.3: 0.431 / Mean: 0.432
- Calibration: The correlation coefficient r for the first and second calibration was > 0.9.

Summarized Results of the Partition Coefficient of the Test Item

Test item	Signal	Peak area [%]	logPOW			Weighted average mean
			1^stCalibration	2^ndCalibration	Mean
pH 4	1	0.10	3.17 ± 0.06 3.02 to 3.32 (95 % CI)	3.17 ± 0.06 3.02 to 3.32 (95 % CI)	3.17	4.65
	2	99.37	4.65 ± 0.09 4.45 to 4.86 (95 % CI)	4.65 ± 0.09 4.45 to 4.86 (95 % CI)	4.65
	3	0.54	5.51 ± 0.11 5.24 to 5.77 (95 % CI)	5.51 ± 0.11 5.24 to 5.77 (95 % CI)	5.51
pH 7	1	21.52	3.14 ± 0.06 2.99 to 3.30 (95 % CI)	3.15 ± 0.06 2.99 to 3.30 (95 % CI)	3.15	4.33
	2	78.48	4.66 ± 0.08 4.46 to 4.86 (95 % CI)	4.66 ± 0.08 4.46 to 4.86 (95 % CI)	4.66
pH 9	1	2.47	2.14 ± 0.02 2.09 to 2.19 (95 % CI)	2.14 ± 0.02 2.09 to 2.19 (95 % CI)	2.14	2.66
	2	97.53	2.67 ± 0.03 2.60 to 2.74 (95 % CI)	2.67 ± 0.03 2.60 to 2.74 (95 % CI)	2.67

P_OW  : Partition coefficient(n-octanol / water)

CI     : Confidence Interval

The identity of the test item signals was verified via additional MS‑detection.

Validity Criteria

- A signal-to-noise ratio > 3 was provided for signals of concern.

- The value of log P_OW derived from repeated measurements made under identical conditions and using the same set of reference items fell within a range of ± 0.1 log units.

- The correlation coefficient r for the calibration curves was > 0.9.

- The column temperature during the measurement did not vary more than± 1 °C.

 

Conclusions:

The partition coefficient log Pow of N-[2-(4-oxo-4H-3,1-benzoaxin-2-yl)phenyl] naphthalene-2-sulphonamide was determined to be:
pH4: 3.17, 4.65 (main) and 5.51 with a weighted average mean value of 4.65 (24.8 °C)
pH7: 3.15 and 4.66 with a weighted average mean value of 4.33 (24.8 °C)
pH9: 2.14 and 2.67 (main) with a weighted average mean value of 2.66 (25.4 °C)

Description of key information

The partition coefficient log P_OW of N-[2-(4-oxo-4H-3,1-benzoaxin-2-yl)phenyl] naphthalene-2-sulphonamide was determined to be:

pH4: 3.17, 4.65 (main) and 5.51 with a weighted average mean value of 4.65 (24.8 °C)

pH7: 3.15 and 4.66 with a weighted average mean value of 4.33 (24.8 °C)

pH9: 2.14 and 2.67 (main) with a weighted average mean value of 2.66 (25.4 °C)