N-(N6-trifluoroacetyl-L-lysyl)-L-proline

pH

Administrative data

Endpoint:

pH

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993-03-22 to 1993-07-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: results taken from a water solubility GLP guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993-03-22 to 1993-07-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

1984

GLP compliance:

yes

Type of method:

flask method

Key result

Water solubility:

> 3.5 other: kg/L

Temp.:

20 °C

pH:

6.6

First addition of the test substance
Flask No.	Additional amount [g]	total Amount [g]	total V (water) [mL]	Concentration [g/L]
1	9.810	19.8076	10.0	1980.8
2	10.7816	21.1248	10.0	2112.5
3	8.6787	19.4638	10.0	1946.4

Second addition of the test substance (additional 4 mL of water)
Flask No.	Additional amount [g]	total Amount [g]	total V (water) [mL]	Concentration [g/L]
1	16.0892	35.8968	14.0	2564.1
2	13.6584	34.7832	14.0	2484.5
3	14.1563	33.6201	14.0	2401.4

Third addition of the test substance
Flask No.	Additional amount [g]	total Amount [g]	total V (water) [mL]	Concentration [g/L]
1	5.1384	41.0352	14.0	2931.1
2	4.9386	39.7218	14.0	2838.3
3	4.9104	38.5305	14.0	2752.2

Fourth addition of the test substance
Flask No.	Additional amount [g]	total Amount [g]	total V (water) [mL]	Concentration [g/L]
1	8.5439	49.5791	14.0	3541.4
2	8.2576	47.9794	14.0	3427.1
3	7.9742	46.5047	14.0	3321.8

By reason of the high viscosity of the solutions a more powerfull stirrer had to be used after the third addition of test substance. Therefore the solutions were transfered into 100 mL Erlenmeyer-flasks. And again after about one hour the test substance was totally dissolved. The fourth additional amount of test substance caused, that no thorough mixing was practicable. For further preparations on next day the solutions were stored in the refrigerator (approx. 6°C).

But on next day the solutions were clear again. Further substance amounts weren't ingenious for the following reasons:

- the highest water solubility already was 3.5 kg/L

- the high viscosity of the solutions prevent a thorough mixing

- in case of full saturation of the solutions a separation

of the solid would be impossible. Because of the above listed reasons the performance was stopped.

Conclusions:

It was impossible to determine the exact water solubilty of ε-Trifluoroacetyl-L-lysyl-L-proline in a test conducted according to EU Method A.6 (1984) so the true value must be higher than the most concentrated solution produced. This solution was also clear at a temperature of 6 °C (refrigerator).Therefore it can be said:
Water Solubility (ε-Trifluoroacctyl-L-lysyl-I-proline, 20°C) > 3-5 kg/L. The pH-value of this solution was: 6.6

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: EEC-Guideline A.6.

Version / remarks:

pH was measured during performance of another test

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N-(N6-trifluoroacetyl-L-lysyl)-L-proline

EC Number:

402-920-1

EC Name:

N-(N6-trifluoroacetyl-L-lysyl)-L-proline

Cas Number:

103300-89-6

Molecular formula:

C13H20F3N3O4

IUPAC Name:

(2S)-1-[(2R)-2-amino-6-(2,2,2-trifluoroacetamido)hexanoyl]pyrrolidine-2-carboxylic acid

Test material form:

solid: particulate/powder

Results and discussion

pH value

Key result

pH value:

6.6

Temp.:

6 °C

Concentration:

> 3 500 g/L

Applicant's summary and conclusion

Conclusions:

According to the results of a test conducted according to EU Method A.6 (Water Solubility), a solution (> 3.5 kg/L) of the substance exhibits a pH of 6.6 at 20°C.