Reaction mass of (3R)-3-[(1R)-4-methyl-3-cyclohexen-1-yl]butanal and (3S)-3-[(1R)-4-methyl-3-cyclohexen-1-yl]butanal

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 October - 30 November 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted in accordance with international guidelines and in accordance with GLP. All relevant validity criteria were met.

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7570 (Partition Coefficient, n-octanol / H2O, Estimation by Liquid Chromatography)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: Assumed stable. Stability at higher temperatures not availbale.
- Solubility and stability of the test substance in the solvent/vehicle: N/A
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: N/A

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

>= 3.7 - <= 4

Temp.:

35 °C

pH:

7

Prelim Test

The log P_owof the test sbstance was calculated to be 3.5, using the Rekker calculation method. The pKa of the test substance was estimated to be 13.81, using the Perrin calculation method.

Main Test

The results of the HPLC method are shown in Table 1. The equation of the regression line was log k' = 0.349 x log Pow - 0.862 (r²= 0.997, n = 12).

Table 1       P_owof the Test Substance

Substance	Retention Time (First Run) (mins)	Retention Time (Second Run) (mins)	Mean Retention Time (mins)	Log Pow	Pow	Area %
Formamide (t0)	0.577	0.578	0.578
Nitrobenzene	0.921	0.919		1.9
Bromobenzene	1.518	1.516		3.0
1,4 -Dichlorobenzene	1.883	1.882		3.4
Biphenyl	2.522	2.520		4.0
1,2,4 -Trichlorobenzene	2.909	2.906		4.2
Dibenzyl	4.172	4.166		4.8
Test Substance - Isomer 1	2.153	2.151	2.152	3.7	5.2 x 10^3	88
Test Substance - Isomer 2	2.492	2.490	2.491	4.0	9.1 x 10^3	12

 

Conclusions:

The log Pow values of the for isomers of the test item at neutral pH were 3.7 and 4.0.

Executive summary:

The log P_owof the test substance (both isomer forms) was determined using the HPLC method in accordance with EU Method A.8.

The partition coefficient (P_ow) of the test substance isomers at neutral pH were 5.2 x 10³and 9.1 x 10³, corresponding to Log P_owvalues of 3.7 and 4.0, respectively.

Since the test substance is a mixture, the Log P_owis reported as a range i.e. 3.7 - 4.0.

Description of key information

Partition coefficient: Log P_ow= 3.7 - 4.0, EU Method A.8 - HPLC method, Anon, 2017. 

Additional information

The log P_owof the test substance (both isomer forms) was determined using the HPLC method in accordance with EU Method A.8.

The partition coefficient (P_ow) of the test substance isomers at neutral pH were 5.2 x 10³and 9.1 x 10³, corresponding to Log P_owvalues of 3.7 and 4.0, respectively.

Since the test substance is a mixture, the Log P_owis reported as a range i.e. 3.7 - 4.0.

The surface tension measurement of < 60 mN/m was not considered to preclude the use of OECD 117 method for partition coefficient (refer to Section 4.8).