Osalmid

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

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:
The Estimation Programs Interface (EPI) SuiteTM

2. MODEL (incl. version number)
MPBPWIN v1.43 (September 2010)

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL:
Oc1c(C(=O)Nc2ccc(O)cc2)cccc1
CAS no. 526-18-1

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
- Defined endpoint: Melting point
- Unambiguous algorithm: MPBPWIN estimates melting point by two different methods.  The first is an adaptation of the Joback group contribution method for melting point (Joback, 1982; Reid et al; 1987) and the second is a simple Gold and Ogle method suggested by Lyman (1985).
 The Joback adaptation in MPBPWIN is an extension of the original method to include the same groups as in the adapted Stein and Brown boiling point method.  In addition, MPBPWIN also uses melting point correction factors for specific structures. A complete list the group descriptors and coefficient values can be seen in the Appendix F of MPBPWIN dossier, available on-line at http://www.epa.gov/tsca-screening-tools/epi-suitetm-estimation-program-interface.
The second estimation method (Gold and Ogle, 1969), simply relates melting point (Tm) to boiling point (Tb) as follows (both values in K):
 Tm  =  0.5839 Tb
MPBPWIN averages the adapted Joback and the Gold and Ogle estimates and reports the average estimate as well as both individual estimates.
For the current EPI Suite, the accuracy of the "suggested" MPBPWIN melting point estimate was tested on a large dataset of 10,051 compounds containing a diverse mix of simple, moderate and very complex structural compounds (includes many pesticides and pharmaceutical compounds).  The dataset was taken from the PHYSPROP Database used by the EPI Suite.  Compounds having "decompose" designations with MP values were excluded.  The complete dataset with experimental values and estimates is available at: http://esc.syrres.com/interkow/EpiSuiteData.htm
Substructure searchable data set of melting point test is available at: http://esc.syrres.com/interkow/EpiSuiteData_ISIS_SDF.htm

- Appropriate measures of goodness-of-fit and robustness and predictivity: r^2 = 0.63; std deviation = 63.9ºC; avg deviation= 48.6ºC
- Mechanistic interpretation: mean value

5. APPLICABILITY DOMAIN
- Descriptor domain: The complete training sets for MPBPWIN's estimation methodology are not available.  Therefore, describing a precise estimation domain for this methodology is not possible.

6. ADEQUACY OF THE RESULT
The estimation is considered acceptable

Reason / purpose for cross-reference:

(Q)SAR model reporting (QMRF)

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

- Gold, P.I. and Ogle, G.J.  1969.  Estimating thermophysical properties of liquids. Part 4 - Boiling, freezing and triple-point temperatures. Chem. Eng. 76: 119
- Joback, K.G.   1982.   A Unified Approach to Physical Property Estimation Using Multivariate Statistical Techniques.  Stevens Institute of Technology, submitted to the Dept. of Chem. Eng. for M.S. Degree at the Massachusetts Institute of Technology in June 1984. (see  also: Reid et al., 1987)
- Lyman, W.J.  1985.   In: Environmental Exposure From Chemicals. Volume I., Neely,W.B. and Blau,G.E. (eds), Boca Raton, FL: CRC Press, Inc., Chapter 2.

Specific details on test material used for the study:

Smiles: Oc1c(C(=O)Nc2ccc(O)cc2)cccc1

Key result

Melting / freezing pt.:

188.38 °C

Remarks on result:

other: QSAR predicted value

MPBPWIN v.1.43 predictec that Osalmid has a melting point of 188.38ºC estimated as a weighted value from the melting point values.

The following data are considered in this estimation:

Melting Point: 349.84 deg C (Adapted Joback Method)

Melting Point: 148.02 deg C (Gold and Ogle Method)

Mean Melt Pt : 248.93 deg C (Joback; Gold,Ogle Methods)

Selected MP: 188.38 deg C (Weighted Value)

Conclusions:

Melting point based on Experimental database form Joback; Gold, Ogle Methods: 179ºC
Estimated value for melting point: 248.93ºC
Selected value for melting point as the most adequate by EPIsuit software: 188.38ºC

Description of key information

1. SOFTWARE:              

      The Estimation Programs Interface (EPI) SuiteTM

2. MODEL (incl. version number)

      MPBPWIN  v1.43 (September 2010)

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL:

      Oc1c(C(=O)Nc2ccc(O)cc2)cccc1

      CAS no. 526-18-1

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL

- Defined endpoint: Melting point

- Unambiguous algorithm: MPBPWIN estimates melting point by two different methods.  The first is an adaptation of the Joback group contribution method for melting point (Joback, 1982; Reid et al; 1987) and the second is a simple Gold and Ogle method suggested by Lyman (1985).

 The Joback adaptation in MPBPWIN is an extension of the original method to include the same groups as in the adapted Stein and Brown boiling point method.  In addition, MPBPWIN also uses melting point correction factors for specific structures. A complete list the group descriptors and coefficient values can be seen in the Appendix F of MPBPWIN dossier, available on-line at http://www.epa.gov/tsca-screening-tools/epi-suitetm-estimation-program-interface.

The second estimation method (Gold and Ogle, 1969), simply relates melting point (Tm) to boiling point (Tb) as follows (both values in K):

 Tm  =  0.5839 Tb

MPBPWIN averages the adapted Joback and the Gold and Ogle estimates and reports the average estimate as well as both individual estimates.

For the current EPI Suite, the accuracy of the "suggested" MPBPWIN melting point estimate was tested on a large dataset of 10,051 compounds containing a diverse mix of simple, moderate and very complex structural compounds (includes many pesticides and pharmaceutical compounds).  The dataset was taken from the PHYSPROP Database used by the EPI Suite.  Compounds having "decompose" designations with MP values were excluded.  The complete dataset with experimental values and estimates is available at: http://esc.syrres.com/interkow/EpiSuiteData.htm

Substructure searchable data set of melting point test is available at: http://esc.syrres.com/interkow/EpiSuiteData_ISIS_SDF.htm

- Appropriate measures of goodness-of-fit and robustness and predictivity:  r^2 = 0.63; std deviation = 63.9ºC; avg deviation= 48.6ºC

- Mechanistic interpretation: mean value

5. APPLICABILITY DOMAIN

- Descriptor domain: The complete training sets for MPBPWIN's estimation methodology are not available.  Therefore, describing a precise estimation domain for this methodology is not possible.       

6. ADEQUACY OF THE RESULT

The estimation is considered acceptable

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

188.38 °C