Reaction products of 1H-Imidazole-1-ethanol, 4,5-dihydro-, 2-(C11-17 and C17 unsatd. alkyl) derivs. and sodium hydroxide and 2-propenoic acid

Dissociation constant

Link to relevant study record(s)

Reference

Endpoint:

dissociation constant

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 limited documentation / justification

Justification for type of information:

1. SOFTWARE
I-Lab 2.0, ilab.acdlabs.com

2. MODEL (incl. version number)
v5.0.0.184

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
[R]C(NCCN(CCO)CCC(O[Na])=O)=O / [R]C(NCCN(CCO)CCC(O)=O)=O

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
see attached information

5. APPLICABILITY DOMAIN
see attached information

6. ADEQUACY OF THE RESULT
The accuracy of calculations for simple structures is usually better than ±0.2 pKa units (for complex structures it is better than ±0.5 pKa units).

Qualifier:

no guideline followed

Principles of method if other than guideline:

Amphopropionates C12-18 is a UVCB substance containing C8-, C10-, C12-, C14-, C16-, and C18-alkyl side chains. Based on this and the variable composition of the compound (alkyl chain distribution dependent on origin of the coco fatty acid) the calculation of physico-chemical properties for the UVCB substance is not feasible. To get a hint on the physico-chemical data, the ACDlabs calculation was conducted for the C12 derivative, because it is the main component of the UVCB substance. The dissociation constants of Amphopropionate C12 were calculated using the freely accessible online version of I-Lab 2.0 Algorithm Version: v5.0.0.184

GLP compliance:

no

Dissociating properties:

yes

No.:

#1

pKa:

3.6

Temp.:

25 °C

No.:

#2

pKa:

7.4

Temp.:

25 °C

No.:

#3

pKa:

14.3

Temp.:

25 °C

No.:

#4

pKa:

15.4

Temp.:

25 °C

Conclusions:

The pKa of Amphopropionate C12 are 3.6±0.4, 7.4±0.4, 14.3±0.5 and 15.4±0.5 at 25°C.

Executive summary:

Amphopropionates C12-18 is a UVCB substance containing C8-, C10-, C12-, C14-, C16-, and C18-alkyl side chains. Based on this and the variable composition of the compound (alkyl chain distribution dependent on origin of the coco fatty acid) the calculation of physico-chemical properties for the

substance is not feasible. To get a hint on the physico-chemical data, the ACDlabs calculation was conducted for the C12 derivative, because it is the main constituent of the UVCB substance. The dissociation constants of Amphopropionate C12 were calculated using the freely accessible online version of I-Lab 2.0 Algorithm Version: v5.0.0.184. The calculation yielded pKa of 3.6±0.4, 7.4±0.4, 14.3±0.5 and 15.4±0.5 at 25°C. The calculations show that there is no pH at which all ionisable groups are in their non-ionised form and that at pH 5.5 the net charge of Amphopropionate C12 is zero.

Description of key information

3.6±0.4, 7.4±0.4, 14.3±0.5 and 15.4±0.5 at 25°C (calculated for C12 chain)

Additional information

Amphopropionates C12-18 is a UVCB substance containing C8-, C10-, C12-, C14-, C16-, and C18-alkyl side chains. Based on this and the variable composition of the compound (alkyl chain distribution dependent on origin of the coco fatty acid) the calculation of physico-chemical properties for the

substance is not feasible. To get a hint on the physico-chemical data, the ACDlabs calculation was conducted for the C12 derivative, because it is the main constituent of the UVCB substance. The dissociation constants of Amphopropionate C12 were calculated using the freely accessible online version of I-Lab 2.0 Algorithm Version: v5.0.0.184. The calculation yielded pKa of 3.6±0.4, 7.4±0.4, 14.3±0.5 and 15.4±0.5 at 25°C. The calculations show that there is no pH at which all ionisable groups are in their non-ionised form and that at pH 5.5 the net charge of Amphopropionate C12 is zero.