Dodecyl 5-oxo-L-prolinate

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
EPISuite

2. MODEL (incl. version number)
WSKOW v1.42

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
SMILES Lauryl PCA is: CCCCCCCCCCCCOC(=O)[C@@H]1CCC(=O)N1

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
- Defined endpoint: water solubility i.e. identical to OECD 105.
- Unambiguous algorithm: provided in WSKOW v1.42 Help, including bibliographic references and all equations.
- Defined domain of applicability: water solubility estimation domains are detailed in WSKOW v1.42 Help.
- Appropriate measures of goodness-of-fit and robustness and predictivity: water solubility estimation domains are detailed in WSKOW v1.42 Help.
- Mechanistic interpretation: The water solubility is a physical property used extensively to describe its solubility in water. The solubility of a substance in water is its saturation concentration in water at a given temperature.

5. APPLICABILITY DOMAIN
The complete datasets used to train and validate the SAR equations used by the WSKOWWIN program are available in two documents prepared for the U.S. Environmental Protection Agency, Office of Pollution Prevention and Toxics (Meylan and Howard, 1994a,b). These documents, which also detail the estimation methodology, can be downloaded from the Internet at: http://esc.syrres.com/interkow/EpiSuiteData.htm
- Descriptor domain:
Range of Molecular Weights in the Training set:
• Minimum: 27.03 (hydrocyanic acid)
• Maximum: 627.62 (hexabromobiphenyl)
Range of Log Kow values in the Training set:
• Minimum: -3.89 (aspartic acid)
• Maximum: 8.27 (decachlorobiphenyl)
Range of Melting points in the Training set:
• Minimum: n/a (liquid)
• Maximum: >200°C (e.g. endrin)
Range of water solubility in the Training set:
• Minimum: 4 x 10-7 mg/L (octachlorodibenzo-p-dioxin)
• Maximum: completely soluble (various)
Lauryl PCA fits perfectly within all above domains.
- Structural and mechanistic domains: water solubility of Lauryl PCA with or without correction is in accordance with WSKOW v1.42.
- Similarity with analogues in the training set:
The training set contains three similar substances depicted below (respectively numbered as substances N°1, 2 and 3).


Substance 1: CAS 2687-96-9, 1-LAURYL-2-PYRROLODONE
Experimental (WSOL = 5.42 mg/L) vs. estimated (run using the same methodology as for LaurylPCA = 2.862 mg/L) water solubility shows a very good fit with a 2-fold underestimation.

Substance 2: CAS 101881-19-0, 1-LAURYL-4-MeO CARBONYL-2-PYRROLODONE
Experimental (WSOL = 13.1 mg/L) vs. estimated (run using the same methodology as for LaurylPCA = 1.676 mg/L) water solubility shows an acceptable fit with an 8-fold underestimation.

Substance 3: CAS N° 14309-41-9, Benzoic acid, 4-amino, octyl ester
Experimental (WSOL = 0.993 mg/L) vs. estimated (run using the same methodology as for LaurylPCA = 2.103 mg/L) water solubility shows a very good fit with a 2-fold overestimation.

The above results suggests that the uncertainty around the result for Lauryl PCA is close to a factor of 2, which is very good.

6. ADEQUACY OF THE RESULT
The prediction fits the purpose of classification/labelling and PBT/vPvB assessment: water solubility is only used as a classification criterion for Aquatic chronic classification of poorly biodegradable substances. As Lauryl PCA is readily biodegradable, water solubility is not used for classification, and it is possible to exclude PBT or vPvB properties.
The prediction fits the purpose of risk assessment: in this dossier, no CSA (exposure and risk assessment) is required, so a calculated water solubility value is sufficient.

Data source

Reference

Reference Type:

other: (Q)SAR report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: ECHA’s Practical guide : How to use and report (Q)SARs Version 3.1 – July 2016

Principles of method if other than guideline:

The estimation methodology used by WSKOWWIN (Meylan and Howard, 1994a,b) is described in the following document prepared for the U.S. Environmental Protection Agency (OPPT): Upgrade of PCGEMS Water Solubility Estimation Method (May 1994). A companion document (Validation of Water Solubility Estimation Methods Using Log Kow for Application in PCGEMS & EPI) also discusses the methodology. WSKOWWIN uses equations 19 and 20 from these documents because they are the best available equations for estimating Wsol.

Equation 19 is: log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Corrections
Equation 20 is: log S (mol/L) = 0.693 - 0.96 log Kow - 0.0092(Tm-25) - 0.00314 MW + Corrections

(where MW is molecular weight, Tm is melting point (MP) in deg C [used only for solids]) ... Corrections are applied to 15 structure types (eg. alcohols, acids, selected phenols, nitros, amines, alkyl pyridines, amino acids, PAHS, multi-nitrogen types, etc); application and magnitude depends on available MP. Equation 20 is used when a measured MP is available; otherwise, equation 19 is used. These equations were derived from a dataset consisting of 1450 compounds with measured log Kow, water sol, and MP. Eq 20 has the following statistical accuracy: correlation coefficient (r2) = 0.97, standard deviation = 0.409 log units, and absolute mean error = 0.313 log units. Application to a validation dataset of 817 compounds gave the following statistical accuracy: correlation coefficient (r2) = 0.902, standard deviation = 0.615 log units, and absolute mean error = 0.480 log units.

WSKOWWIN estimates a log Kow for every SMILES notation by using the estimation engine from the KOWWIN Program (SRC, 2000). WSKOWWIN also automatically retrieves experimental log Kow values from a database containing more than 13200 organic compounds with reliably measured values. When a SMILES structure matches a database structure (via an exact atom-to-atom connection match), the experimental log Kow value is retrieved and used to predict Wsol rather than the estimated value.

WSKOWWIN v1.4 includes an experimental water solubility database of 6230 compounds. When experimental data are available for the SMILES being estimated, the data are retrieved and shown in the Results Window.

GLP compliance:

no

Type of method:

other: Calculation method

Test material

Test material information

Constituent 1

Reference substance name:

Dodecyl 5-oxo-L-prolinate

EC Number:

245-224-1

EC Name:

Dodecyl 5-oxo-L-prolinate

Cas Number:

22794-26-9

Molecular formula:

C17H31NO3

IUPAC Name:

dodecyl 5-oxo-L-prolinate

Results and discussion

Water solubility

Key result

Water solubility:

0.62 mg/L

Temp.:

25 °C

Remarks on result:

other: pH not applicable for (Q)SAR

Applicant's summary and conclusion

Conclusions:

WSKOW v1.42 enabled to estimate a value of Lauryl PCA water solubility as 0.62 mg/L with a good reliability and fit for purpose of classification/labelling and PBT/vPvB/risk assessments.