Iron(II) oxalate

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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 limited documentation / justification

Justification for type of information:

1. SOFTWARE and MODEL
EPI Suite version 4.11
Kowwin v1.68 (september 2010)

2. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
SMILES : C1(=O)(C(=O)[O-])O[Fe]O
NAME : iron oxalate
CAS Number : 516-03-0

3. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
No formal QMRF assessment of the model is currently available, however, the user's guide describes all the information.
- Defined endpoint: Partition coefficient
- Methodology : KOWWIN uses a "fragment constant" methodology to predict log P.  In a "fragment constant" method, a structure is divided into fragments (atom or larger functional groups) and coefficient values of each fragment or group are summed together to yield the log P estimate. KOWWIN’s methodology is known as an Atom/Fragment Contribution (AFC) method.  Coefficients for individual fragments and groups were derived by multiple regression of 2447 reliably measured log P values.  KOWWIN’s "reductionist" fragment constant methodology (i.e. derivation via multiple regression) differs from the "constructionist" fragment constant methodology of Hansch and Leo (1979) that is available in the CLOGP Program (Daylight, 1995).  See the Meylan and Howard (1995) journal article for a more complete description of KOWWIN’s methodology.

To estimate log P, KOWWIN initially separates a molecule into distinct atom/fragments.  In general, each non-hydrogen atom (e.g. carbon, nitrogen, oxygen, sulfur, etc.) in a structure is a "core" for a fragment; the exact fragment is determined by what is connected to the atom.  Several functional groups are treated as core "atoms"; these include carbonyl (C=O), thiocarbonyl (C=S), nitro (-NO2), nitrate (ONO2), cyano (-C/N), and isothiocyanate (-N=C=S).  Connections to each core "atom" are either general or specific; specific connections take precedence over general connections.

4. APPLICABILITY DOMAIN
No formal QMRF assessment of the model is currently available, however, the user's guide describes all the information.
- Descriptor domain: organic chemical
- Structural and mechanistic domains:
Training Set Molecular Weights: Minimum MW:  18.02 Maximum MW:  719.92 Average MW:  199.98
Appendix D of the KOWWIN Help gives the maximum number of fragments that occur in any individual compound of the training set.
- Similarity with analogues in the training set: The KOWWIN training and validation datasets can be downloaded from the Internet at http://esc.syrres.com/interkow/KowwinData.htm

5. References
Daylight.  1995.  CLOGP Program. Daylight Chemical Information Systems.  Von Karman Ave., Irvine, CA 92715. (web-site as of March 2008: http://www.daylight.com/)
Hansch, C and  Leo, A.J.  1979.  Substituent Constants for Correlation Analysis in Chemistry and Biology;  Wiley: New York, 1979.
Meylan, W.M. and P.H. Howard.  1995.  Atom/fragment contribution method for estimating octanol-water partition coefficients.  J. Pharm. Sci. 84: 83-92.

Guideline:

other: REACH guidance on QSARs R.6

Principles of method if other than guideline:

- Software tool(s) used including version: Kowwin v1.68 (september 2010)
- Model(s) used: Kowwin v1.68 (september 2010)
- Model description: see field 'Justification for type of information"
- Justification of QSAR prediction: see field 'Attached justification'

GLP compliance:

no

Specific details on test material used for the study:

SMILES : C1(=O)(C(=O)[O-])O[Fe]O

Type:

log Pow

Partition coefficient:

ca. -1.17

Remarks on result:

other: QSAR predicted value

KOWWIN predicted that iron oxalate has a logKow = -1.17

Conclusions:

KOWWIN predicted that iron oxalate has a logKow = -1.17

Executive summary:

KOWWIN predicted that iron oxalate has a logKow = -1.17

Reference 2

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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 and MODEL
OPERA-Model for Octanol-water partition
OPERA v1.5

2. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
SMILES : C1(=O)(C(=O)[O-])O[Fe]O
NAME : iron oxalate
CAS Number : 516-03-0

3. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See QMRF_LogKow_iron oxalate-OPERA_Q17-16-0016_document

4. APPLICABILITY DOMAIN
See QMRF_LogKow_iron oxalate-OPERA_Q17-16-0016_document

Guideline:

other: REACH guidance on QSARs R.6

Principles of method if other than guideline:

- Software tool(s) used including version: OPERA-model for octano-water paritition
- Model(s) used: v1.5 (2016)
- Model description: see field 'Justification for type of information"
- Justification of QSAR prediction: see field 'Attached justification'

GLP compliance:

no

Specific details on test material used for the study:

SMILES : C1(=O)(C(=O)[O-])O[Fe]O

Type:

log Pow

Partition coefficient:

ca. -0.855

Remarks on result:

other: QSAR predicted value

OPERA predicted that iron oxalate has a logKow = -0.855

Conclusions:

OPERA predicted that iron oxalate has a logKow = -0.855

Executive summary:

OPERA predicted that iron oxalate has a logKow = -0.855

Description of key information

QSAR prediction with a good reliability predicted that iron oxalate has a logKow :

• -1.17 with Kowwin
• -0.855 with OPERA

All these data indicates that iron oxalate has a low partitient coefficient.

The OPERA value is retained as this QSAR confirmed to be in the applicability domain.

Key value for chemical safety assessment

Log Kow (Log Pow):

-0.855