1H-Pyrazolo[3,4-c]pyridine-3-carboxylic acid, 4,5,6,7-tetrahydro-1-(4-methoxyphenyl)-6-(4-nitrophenyl)-7-oxo-, ethyl ester

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 5 to September 17, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

ethyl 1-(4-methoxyphenyl)-6-(4-nitrophenyl)-7-oxo-1H,4H,5H,6H,7H-pyrazolo[3,4-c]pyridine-3-carboxylate

EC Number:

611-033-0

Cas Number:

536759-91-8

Molecular formula:

C22H20N4O6

IUPAC Name:

ethyl 1-(4-methoxyphenyl)-6-(4-nitrophenyl)-7-oxo-1H,4H,5H,6H,7H-pyrazolo[3,4-c]pyridine-3-carboxylate

Test material form:

solid: particulate/powder

Details on test material:

powder; stored at room temperature in the dark

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

New Zealand White rabbits were supplied by Harlan Ltd., UK.; acclimatisation period of at least 26 days; At the start of the study the animals were in the weight range of 2.77 to 3.0 kg and up to eight weeks old. Free access to mains drinking water and food was allowed through out the study. The temperature and relative humidity were set to achieve limits of 15 to 23 C and 40 to 70% respectively. The rate of air exchange was at least 15 changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours of darkness.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 g of the test material, moistened with 0.5 ml of reverse osmosis water was introduced under 2.5 cm X 2.5 cm cotton gauze patch

Duration of treatment / exposure:

A single animal received three treatments first with the patch removed at 3 mins, 1 hr and 4 hours as preliminary screening. . The patch was removed after four hours and any residual material removed from the test area by gentle swabbing with luke warm water. Blotted dry with absorbant paper.

Observation period:

Approximately one hour after removing the patch and 24, 48 and 72 hours later, the test sites were examined for evidence of primary irritation and scored.

Number of animals:

3

Details on study design:

The day before the test the three rabbits were clipped free of fur from the dorsal/flank area and inspected for gross abnormalities of the epidermis. Only animals with an intact healthy epidermis are selected for the study. A suitable site on the back of each rabbit was selected as test site and 0.5 g of test material moistened with 0.5 ml of distilled water was introduced under a 2.5 cm X 2.5 cm cotton gauze patch which was secured in position with surgical tape. After patch removal, the test sites were evaluated after 1 hour, 24, 48, and 72 hours according to the Draize classification scheme for determination of irritation.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 1, 24,48 and 72 hr

Score:

0

Max. score:

0

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 1, 24, 48 and 72 hrs

Score:

0

Max. score:

0

Irritant / corrosive response data:

The individual scores for erythema/eschar and oedema were all zero for all three animals for the complete 72 hour observation period. No evidence of skin irritation was noted during the study except for one animal with a very slight irritation noted at one hour after bandage removal.

Other effects:

No evidence of skin irritation was noted during the study except very slight erthyema in one animal one hour after removal of the bandage. There were no signs of systemic toxicity

Applicant's summary and conclusion

Interpretation of results:

not irritating

Conclusions:

The test material produced a score of 0.0 and was classified as a non-irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted. The test material did not meet the classification as irritant or corrosive according to the EU labelling regulations.