Endo-8-isopropyl-8-azabicyclo[3.2.1]octan-3-ol

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 May - 07 Sep 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

no

Remarks:

None, because measured temperatures are minimum and maximum temperatures which occurred only for short time intervals.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

1992

Deviations:

no

GLP compliance:

not specified

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Endo-8-isopropyl-8-azabicyclo[3.2.1]octan-3-ol

EC Number:

222-314-9

EC Name:

Endo-8-isopropyl-8-azabicyclo[3.2.1]octan-3-ol

Cas Number:

3423-25-4

Molecular formula:

C10H19NO

IUPAC Name:

Endo-8-isopropyl-8-azabicyclo[3.2.1]octan-3-ol

Test material form:

solid: particulate/powder

Results and discussion

Water solubility

Key result

Water solubility:

30.2 g/L

Conc. based on:

test mat.

Temp.:

21 °C

Remarks on result:

other: 30.2 g/L (mean value, 1.6 g/L standard deviation); temperature was kept constant within ± 1°C.

Details on results:

Data handling: The solubility of the test item in water is specified by the saturation mass concentration of the test item in water at a given temperature. The solubility in water was specified in units of mass per volume of solution (g/L).
The water solubility of the test item N-Isopropylnortropin was estimated using the flask method. The saturation concentration of the test item was determined using photometrical method.
The linearity of the analytical method was proved in the concentration range from 30 to 100 mg test item/L. The regression coefficient was determined to be 0.99.

Any other information on results incl. tables

The results of the measurements of the test samples are summarized in table 1. No differences hifgher than 12% were foumd between samples 1,2,3,4,5, and 6. Therefore, the study is considered to be valid.

 

Table 1. Results for the Determination of the Water Solubility of the Test Item

sample	descriptionb age [h]	concentration found [mg/L]^1	Dilution factor	concentration calculated [g/L]	measured pH^2after incubation
11172185	72	58.59	500	29.3	12
11172185	72	57.13	500	28.6	12
11172185	48	57.49	500	28.7	12
11172185	48	63.73	500	31.9	12
11172185	24	60.43	500	30.2	12
11172185	24	64.46	500	32.2	12

¹ rounded value calculated from regression data

² measured with indicatior strips

 

Corresponding to the analysis the water solubility of the test item was calculated to be 30.2 g/L.

 

Qualification:

Injected samples were quantified by measuring the absorption unit at 210 nm with reference to the calibration curve. The latter was obtained by correlation of absorption units of the reference solution to their corresponding concentration in mg/L. The correlation was performed using a linear regression function given by equation (1):

y = a* x + b  (1)

where

y = absorption unit

x = concentration of the test item in the samples [mg/L]

a = slope

b = y-axis intercept

 

The concentration of the test item in the test samples will be calculated by equation (2):

c = x* d  (2)

where

c = concentration of test item in test sample [mg/L]

x = concentration of test item found in the samples [mg/L]

d = dilution factor

 

 

Applicant's summary and conclusion

Conclusions:

The water solubility of N-Isopropylnortropin was estimated to be higher than 0.1 g/L in a preliminary test.
The water solubility of N-Isopropylnortropin was calculated to be 30.2 g/L (mean value, 1.6 g/L; standard deviation) at 21°C ± 1 °C using the flask method for the performance of the main test.