N-[(1R)-2-[(Methylsulfonyl)oxy]-1-phenylethyl]carbamic acid 1,1-dimethylethyl ester

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

3 September - 25 September 2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

The specific guideline followed was not specified in the study report. A standard plate incorporation procedure was followed.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl N-[(1R)-2-(methanesulfonyloxy)-1-phenylethyl]carbamate

EC Number:

855-580-5

Cas Number:

102089-75-8

Molecular formula:

C14H21NO5S

IUPAC Name:

tert-butyl N-[(1R)-2-(methanesulfonyloxy)-1-phenylethyl]carbamate

Test material form:

solid: particulate/powder

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced rat liver microsomes (S9 fraction, Moltox, Lot No. 3271) were used to prepare S9 mix.

Test concentrations with justification for top dose:

The test article was formulated in actetone at a stock concentration of 50 mg/mL. Lowerconcentrations were prepared by dilution with acetone. Final concentrations of test article per well were 17, 28, 47, 78, 130, 216, 200, 600 and 1000 µg/well.

Vehicle / solvent:

Acetone was used as the vehicle control

Controls

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

2-nitrofluorene

sodium azide

other: N-methyl-N'-nitro-N-nitrosoquanidine, 2-aminoanthracene

Details on test system and experimental conditions:

Test Compound and Study Design:
A plate incorporation procedure, using conditions without and with S9 metabolic activation, was utilized. Acetone was used as the vehicle control. The test article was formulated in actetone at a stock concentration of 50 mg/mL. Lower concentrations were prepared by dilution with acetone. Final concentrations of test article per well were 17, 28, 47, 78, 130, 216, 200, 600 and 1000 μg/well. Positive control compounds were N-methyl- N'-nitro-N- nitrosoguanidine (MNNG), 2-nitrofluorene (NF), Sodium azide (NaAz), 9-aminoacridine (9A), 4-nitroquinoline-n- oxide (4QNO) and 2- aminoanthracene (AA). Two, 6-well plates were prepared for vehicle and positive controls and duplicate wells were prepared for all test compound combinations. The 6- well plates were incubated at approximately 37°C for approximately 48 hours.

The numbers of colonies in each well were counted and the means were calculated. The mean number of colonies per treatment condition was compared for the test compound-treated and vehicle control-treated wells. No comparative statistical analyses were performed. The results of the study were evaluated using the following criteria:

If the vehicle control value was within the historical range, a test article that produced a response with the highest increase equal to or exceeding twice the vehicle control value with Salmonella strains TA98, TA100 or E. coli strain WP2uvrApKM101 and three times the vehicle control value with Salmonellastrains TA1535 or TA1537, was considered mutagenic. A concentration-related increase was expected in a positive mutagenic response.

Evaluation criteria:

If the vehicle control value was within the historical range, a test article that produced a response with the highest increase equal to or exceeding twice the vehicle control value with Salmonella strains TA98, TA100 or E. coli strain WP2uvrApKM101 and three times the vehicle control value with Salmonella strains TA1535 or TA1537, was considered mutagenic. A concentration-related increase was expected in a positive mutagenic response.

Results and discussion

Test results

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

The results indicate that the test material was positive (mutagenic) in the 6-well 5-strain bacterial reverse mutation assay for S. typhimurium TA 1535 in the presence of metabolic activation.