(Z)-α-[[2-(tert-butoxy)-1,1-dimethyl-2-oxoethoxy]imino]-2-(tritylamino)thiazol-4-acetic acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 October 2017 to 13 October 2017

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(Z)-α-[[2-(tert-butoxy)-1,1-dimethyl-2-oxoethoxy]imino]-2-(tritylamino)thiazol-4-acetic acid

EC Number:

272-056-6

EC Name:

(Z)-α-[[2-(tert-butoxy)-1,1-dimethyl-2-oxoethoxy]imino]-2-(tritylamino)thiazol-4-acetic acid

Cas Number:

68672-66-2

Molecular formula:

C32H33N3O5S

IUPAC Name:

(2Z)-2-({[1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl]oxy}imino)-2-{2-[(triphenylmethyl)amino]-1,3-thiazol-4-yl}acetic acid

Test material form:

solid: particulate/powder

Details on test material:

white powder

Specific details on test material used for the study:

Identification: 1132 Side Chain
Batch: 14TATT-S01025C
Purity: 100.1% w/w (HPLC Analysis)
Physical state/Appearance: White powder
Expiry Date: 24 December 2017

In vitro test system

Test system:

human skin model

Source species:

human

Vehicle:

unchanged (no vehicle)

Details on test system:

Supplier : MatTek
Date received : 10 October 2017
EpiDermTM Tissues (0.63cm2) lot number : 25848
Assay Medium lot number : 100517ALC
Upon receipt of the EpidermTM tissues, the sealed 24-well plate was stored in a refrigerator until use

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minutes

Value:

85.5

Vehicle controls validity:

valid

Negative controls validity:

valid

Remarks:

100% viability

Positive controls validity:

valid

Remarks:

4.2

Remarks on result:

no indication of irritation

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minutes

Value:

98.3

Negative controls validity:

valid

Remarks:

100

Positive controls validity:

valid

Remarks:

3.2

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

The mean OD570 for the negative control treated tissues was 1.420 for the 3-Minute exposure period and 1.360 for the 60-Minute exposure period. The negative control acceptance criteria were therefore satisfied.
The relative mean tissue viability for the positive control treated tissues was 3.2% relative to the negative control following the 60-Minute exposure period. The positive control acceptance criterion was therefore satisfied. In the range 20 to 100% viability the Coefficient of Variation between the two tissue replicates of each treatment group did not exceed 30%. The acceptance criterion was therefore satisfied.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was considered to be non-corrosive to the skin.

Executive summary:

Duplicate tissues were treated with the test item for exposure periods of 3 and 60 minutes. Negative and positive control groups were treated for each exposure period. At the end of the exposure period the test item was rinsed from each tissue before each tissue was taken for MTT-loading. After MTT loading each tissue was placed in 2 mL Isopropanol for MTT extraction. At the end of the formazan extraction period each well was mixed thoroughly and triplicate 200 µL samples were transferred to the appropriate wells of a pre-labeled 96-well plate. The optical density (OD) was measured at 570 nm (OD570). Data are presented in the form of percentage viability (MTT reduction in the test item treated tissues relative to negative control tissues). The quality criteria required for acceptance of results in the test were satisfied. The test item was considered to be non-corrosive to the skin.