2-[(4-chloro-2-nitrophenyl)azo]-N-(4-ethoxyphenyl)-3-oxobutyramide

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide (52320-66-8). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system.2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N- (4-ethoxyphenyl)-3-oxobutanamide was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro. Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

Data is from OECD QSAR Toolbox version 3.3 and the supporting QMRF report has been attached.

Qualifier:

according to guideline

Guideline:

other: As mention below

Principles of method if other than guideline:

Prediction is done using OECD QSAR Toolbox version 3.3, 2017

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Name of test material (IUPAC name): 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide
- Molecular formula: C18H17ClN4O5
- Molecular weight: 404.808 g/mol
- Smiles notation: O=C(Nc1ccc(OCC)cc1)[C@@H](\N=N\c1c([N+](=O)[O-])cc(cc1)Cl)C(=O)C
- InChl: 1S/C18H17ClN4O5/c1-3-28-14-7-5-13(6-8-14)20-18(25)17(11(2)24)22-21-15-9-4-12(19)10-16(15)23(26)27/h4-10,17H,3H2,1-2H3,(H,20,25)/b22-21+
- Substance type: Organic
- Physical state: Solid

Target gene:

Histidine

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Details on mammalian cell type (if applicable):

Not applicable.

Additional strain / cell type characteristics:

not specified

Cytokinesis block (if used):

not specified

Metabolic activation:

with

Metabolic activation system:

S9 metabolic activation

Test concentrations with justification for top dose:

not specified

Vehicle / solvent:

not specified

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

not specified

Details on test system and experimental conditions:

not specified

Rationale for test conditions:

not specified

Evaluation criteria:

Prediction was done considering a dose dependent increase in the number of revertants/plate.

Statistics:

not specified

Species / strain:

S. typhimurium, other:

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Remarks on result:

other: No mutagenic effect were observed

The prediction was based on dataset comprised from the following descriptors: "Gene mutation"
Estimation method: Takes highest mode value from the 6 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" and ("b" and ( not "c") )  )  and ("d" and ( not "e") )  )  and ("f" and ( not "g") )  )  and ("h" and ( not "i") )  )  and ("j" and ( not "k") )  )  and ("l" and ( not "m") )  )  and ("n" and "o" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Amides by Aquatic toxicity classification by ECOSAR

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Aromatic azo AND SN1 >> Nitrenium Ion formation >> Aromatic nitro by DNA binding by OECD

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Acylation OR Acylation >> P450 Mediated Activation to Isocyanates or Isothiocyanates OR Acylation >> P450 Mediated Activation to Isocyanates or Isothiocyanates >> Benzylamines-Acylation OR Acylation >> P450 Mediated Activation to Isocyanates or Isothiocyanates >> Formamides OR Michael addition OR Michael addition >> P450 Mediated Activation of Heterocyclic Ring Systems OR Michael addition >> P450 Mediated Activation of Heterocyclic Ring Systems >> Furans OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> 5-alkoxyindoles OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Alkyl phenols OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Arenes OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Hydroquinones OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Polycyclic (PAHs) and heterocyclic (HACs) aromatic hydrocarbons-Michael addition OR Michael addition >> Polarised Alkenes-Michael addition OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated esters OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated ketones OR No alert found OR Schiff base formers OR Schiff base formers >> Chemicals Activated by P450 to Glyoxal  OR Schiff base formers >> Chemicals Activated by P450 to Glyoxal  >> Ethanolamines (including morpholine) OR Schiff base formers >> Chemicals Activated by P450 to Mono-aldehydes OR Schiff base formers >> Chemicals Activated by P450 to Mono-aldehydes >> Thiazoles OR Schiff base formers >> Direct Acting Schiff Base Formers OR Schiff base formers >> Direct Acting Schiff Base Formers >> Alpha-beta-dicarbonyl OR SN1 >> Carbenium Ion Formation OR SN1 >> Carbenium Ion Formation >> Hydrazine OR SN1 >> Carbenium Ion Formation >> N-Nitroso (alkylation) OR SN1 >> Carbenium Ion Formation >> Polycyclic (PAHs) and heterocyclic (HACs) aromatic hydrocarbons-SN1 OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion Formation >> Aliphatic tertiary amines OR SN1 >> Nitrenium Ion formation >> Aromatic N-hydroxylamines OR SN1 >> Nitrenium Ion formation >> Aromatic nitroso OR SN1 >> Nitrenium Ion formation >> Primary (unsaturated) heterocyclic amine OR SN1 >> Nitrenium Ion formation >> Primary aromatic amine OR SN1 >> Nitrenium Ion formation >> Secondary (unsaturated) heterocyclic amine OR SN1 >> Nitrenium Ion formation >> Secondary aromatic amine OR SN1 >> Nitrenium Ion formation >> Tertiary aromatic amine OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic nitro OR SN2 OR SN2 >> Direct Acting Epoxides and related OR SN2 >> Direct Acting Epoxides and related >> Aziridines OR SN2 >> Direct Acting Epoxides and related >> Epoxides OR SN2 >> Episulfonium Ion Formation OR SN2 >> Episulfonium Ion Formation >> Mustards OR SN2 >> Nitrosation-SN2 OR SN2 >> Nitrosation-SN2 >> Nitroso-SN2 OR SN2 >> SN2 at a Nitrogen atom OR SN2 >> SN2 at a Nitrogen atom >> N-acyloxy-N-alkoxyamides OR SN2 >> SN2 at an sp3 Carbon atom OR SN2 >> SN2 at an sp3 Carbon atom >> Aliphatic halides by DNA binding by OECD

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Ester aminolysis AND Acylation >> Ester aminolysis >> Amides by Protein binding by OASIS v1.3

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Michael Addition OR Michael Addition >> Michael type addition on azoxy compounds OR Michael Addition >> Michael type addition on azoxy compounds >> Azoxy compounds  OR Michael Addition >> Quinoide type compounds OR Michael Addition >> Quinoide type compounds >> Quinone methide(s)/imines; Quinoide oxime structure; Nitroquinones, Naphthoquinone(s)/imines  OR No alert found by Protein binding by OASIS v1.3

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Direct Acylation Involving a Leaving group AND Acylation >> Direct Acylation Involving a Leaving group >> Acetates AND SN2 AND SN2 >> SN2 reaction at sp3 carbon atom AND SN2 >> SN2 reaction at sp3 carbon atom >> Alkyl diazo by Protein binding by OECD

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No alert found by Protein binding by OECD

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as H-acceptor-path3-H-acceptor AND Nitro-aromatic by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as 1-phenoxy-benzene OR Aromatic diazo OR Aromatic N-acyl amine OR Heterocyclic Polycyclic Aromatic Hydrocarbons OR Hydrazine by in vivo mutagenicity (Micronucleus) alerts by ISS

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Halogens AND Non-Metals by Groups of elements

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Alkali Earth by Groups of elements

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Dantrolene (Hepatotoxicity) Alert by Repeated dose (HESS)

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of log Kow which is >= 2.6

Domain logical expression index: "o"

Parametric boundary:The target chemical should have a value of log Kow which is <= 7.05

Conclusions:

2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide (52320-66-8) was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Executive summary:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide (52320-66-8). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Genetic mutation in vitro;

Prediction model based estimation and data from read across chemical have been reviewed to determine the mutagenic nature of 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N- (4-ethoxyphenyl)-3-oxobutanamide (52320-66-8). The studies are as mentioned below

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide (52320-66-8). The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system.2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N- (4-ethoxyphenyl)-3-oxobutanamide was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro. Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, chromosomal aberration was predicted for2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide (52320-66-8)  .The study assumed the use of Chinese hamster ovary (CHO) cell line with and without S9 metabolic activation system 2-[(E)-2-(4-chloro-2-nitrophenyl)diazen-1-yl]-N-(4-ethoxyphenyl)-3-oxobutanamide was predicted to not induce chromosomal aberrations in Chinese hamster ovary (CHO) cell line in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro. Based on the predicted result it can be concluded that the substance is considered to not toxic as per the criteria mentioned in CLP regulation.

In a study for structurally and functionally similar read across chemical, Gene mutation toxicity study was performed by Errol Zeiger at al.( Environmental and Molecular Mutagenesis, 1988) to determine the mutagenic nature of C. I. Pigment Yellow 74 (6358-31-2) IUPAC name; 2-[(2-methoxy-4-nitrophenyl)azo]-N-(2-methoxyphenyl)-3-oxobutyramide . The read across substances share high similarity in structure and log kow .Therefore, it is acceptable to derive information on mutation from the analogue substance. Genetic toxicity study was assessed for C. I. Pigment Yellow 74 to evaluate its possible mutagenic potential. For this purpose the test material was exposed to Salmonella typhimurium TA97, TA98, TA100, TA1535 by AMES test. The test material was exposed at the concentration of 0, 10, 33,100,333,667,1000and 2000 ug/plate in the presence and absence of metabolic activation. No mutagenic effects were observed. Therefore C. I. Pigment Yellow 74 was considered to be non mutagenic in the presence and absence of metabolic activation. Hence the substance cannot be classified as gene mutant in vitro.

In a study for structurally and functionally similar read across chemical, Gene mutation toxicity study was performed by National Institute of Technology and Evaluation (Japan chemicals collaborative knowledge database, 2017) to determine the mutagenic nature of 2C.I Pigment orange 16 (6505-28-8)IUPAC name;2,2'-[(3,3'-dimethoxybiphenyl-4,4'-diyl)didiazene-2,1-diyl]bis(3-oxo-N-phenylbutanamide).The read across substances share high similarity in structure and log kow .Therefore, it is acceptable to derive information on mutation from the analogue substance. Genetic toxicity was performed onSalmonella typhimurium (TA100, TA1535, TA98, TA1537) and Escherichia coli (WP2 uvrA) with and without activation when treated with C.I Pigment orange 16 (6505-28-8) under OECD Test Guideline 471.The method use was Pre-incubation method and solvent was dimethyl sulphoxide. Different dose were used in with and without activation. The concentration used for this test were mention below

-S9 mix; 0, 4.88, 9.77, 19.5, 39.1, 78.1, 156, 313 µg/plate(TA100, TA1535, TA98, TA1537)

 

-S9 mix; 0, 39.1, 78.1, 156, 313, 625, 1250, 2500, 5000 µg/plate (WP2 uvrA)

 

+S9 mix; 0, 4.88, 9.77, 19.5, 39.1, 78.1, 156, 313 µg/plate (TA100, TA1535, TA98, TA1537)

 

+S9 mix; 0, 39.1, 78.1, 156, 313, 625, 1250, 2500, 5000 µg/plate (WP2 uvrA)

 

+S9 mix(additional test, Hamster S9); 0, 1.17, 2.34, 4.69, 9.38, 18.8,37.5, 75.0, 150, 300 µg/plate (TA98)

No increase in revertants colonies was observed in the test with either the non-activation method (- S9) or activation (+S9) in Salmonella typhimurium and Escherichia coli.Therefore, the genetic toxicity on Salmonella typhimurium(TA100, TA1535, TA98, TA1537) and Escherichia coli (WP2 uvrA) was considered to be negative (with and without) when treated with C.I Pigment orange 16 (6505-28-8). Hence the substance cannot be classified as gene mutant in vitro.

Based on the data available for the target chemical and its read across substance and applying weight of evidence of 2-[(E)-2-(4-chloro-2-nitrophenyl) diazen-1-yl]-N- (4-ethoxyphenyl)-3-oxobutanamide (52320-66-8) does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant in vitro.

Justification for classification or non-classification

Based on the above annotation and CLP criteria for the target chemical ,2-[(E)-2-(4-chloro-2-nitrophenyl) diazen-1-yl]-N- (4-ethoxyphenyl)-3-oxobutanamide (52320-66-8) does not exhibit gene mutation in vitro. Hence the test chemical is not likely to classify as a gene mutant in vitro.