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EC number: 229-043-5 | CAS number: 6407-78-9
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
The skin sensitization potential of target chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) was assessedin various experimental studies which were conducted on guinea pigs and humans for target chemical4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) and its structurally similar read across substance Edaravone(CAS No:-89-25-8) and functionally similar read across substance C.I. Pigment Red 3(CAS No: 2425-85-6). The predicted data usingQSAR toolboxhas also been compared with the experimental data.Based on the available data for the target and read across substances and applying the weight of evidence approach, it can be concluded that chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) is unable to cause skin sensitization and thus can be considered as not sensitizing. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Not Classified”.
Key value for chemical safety assessment
Skin sensitisation
Link to relevant study records
- Endpoint:
- skin sensitisation: in vivo (non-LLNA)
- 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 QMRF report has been attached
- Qualifier:
- according to guideline
- Guideline:
- other: estimated data
- Principles of method if other than guideline:
- Prediction is done using QSAR Toolbox version 3.3
- GLP compliance:
- not specified
- Type of study:
- Buehler test
- Justification for non-LLNA method:
- not specified
- Specific details on test material used for the study:
- - Name of test material (IUPAC name): 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one
- Common name: Solvent Yellow 18
- Molecular formula: C18H18N4O
- Molecular weight: 306.367 g/mol
- Smiles notation: O=C1N(N=C(C)[C@@H]1\N=N\c1c(cc(cc1)C)C)c1ccccc1
- InChl: 1S/C18H18N4O/c1-12-9-10-16(13(2)11-12)19-20-17-14(3)21-22(18(17)23)15-7-5-4-6-8-15/h4-11,17H,1-3H3/b20-19+
- Substance type: Organic
- Physical state: Solid - Species:
- guinea pig
- Strain:
- other: Pirbright White
- Sex:
- not specified
- Details on test animals and environmental conditions:
- No data available
- Route:
- epicutaneous, occlusive
- Vehicle:
- not specified
- Concentration / amount:
- No data available
- Day(s)/duration:
- No data available
- Adequacy of induction:
- not specified
- No.:
- #1
- Route:
- epicutaneous, occlusive
- Vehicle:
- not specified
- Concentration / amount:
- No data available
- Day(s)/duration:
- 48 hours
- Adequacy of challenge:
- not specified
- No. of animals per dose:
- 10
- Details on study design:
- No data available
- Reading:
- 1st reading
- Hours after challenge:
- 48
- Group:
- test chemical
- Dose level:
- No data available
- No. with + reactions:
- 0
- Total no. in group:
- 10
- Clinical observations:
- No skin sensitization was observed in treated guinea pigs.
- Remarks on result:
- no indication of skin sensitisation
- Cellular proliferation data / Observations:
- No skin sensitization was observed in treated guinea pigs.
- Interpretation of results:
- other: Not sensitizing
- Conclusions:
- The chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) was estimated to be not sensitizing to the skin of Pirbright White guinea pigs. Based on the estimated result 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) failed to induce skin sanitization effects and hence is considered to be not sensitizing to Pirbright White guinea pigs.
- Executive summary:
The skin sensitization potential of 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) was estimated using OECD QSAR toolbox version 3.3 with log Pow as the primary descriptor. The chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) was estimated to be not sensitizing to the skin of Pirbright White guinea pigs. Based on the estimated result 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) failed to induce skin sanitization effects and hence is considered to be not sensitizing to Pirbright White guinea pigs and can be classified under the category ˋ Not Classified’ as per CLP regulation.
Reference
The
prediction was based on dataset comprised from the following
descriptors: "Skin Sensitisation"
Estimation method: Takes highest mode value from the 9 nearest neighbours
Domain logical expression:Result: Out of Domain
(((((((("a"
or "b" or "c" or "d" or "e" or "f" or "g" )
and ("h"
and (
not "i")
)
)
and ("j"
and (
not "k")
)
)
and "l" )
and "m" )
and ("n"
and (
not "o")
)
)
and ("p"
and (
not "q")
)
)
and ("r"
and "s" )
)
Domain
logical expression index: "a"
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 >> Unsaturated heterocyclic azo by DNA binding
by OECD
Domain
logical expression index: "b"
Referential
boundary: The
target chemical should be classified as Schiff base formation AND Schiff
base formation >> Pyrazolones and Pyrazolidinones derivatives AND Schiff
base formation >> Pyrazolones and Pyrazolidinones derivatives >>
Pyrazolones and Pyrazolidinones by Protein binding by OASIS v1.3
Domain
logical expression index: "c"
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: "d"
Referential
boundary: The
target chemical should be classified as Amides AND Hydrazines by Aquatic
toxicity classification by ECOSAR
Domain
logical expression index: "e"
Referential
boundary: The
target chemical should be classified as Amides OR Hydrazines by Aquatic
toxicity classification by ECOSAR ONLY
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 Amides AND Hydrazines by Aquatic
toxicity classification by ECOSAR
Domain
logical expression index: "h"
Referential
boundary: The
target chemical should be classified as No alert found by DNA binding by
OASIS v.1.3
Domain
logical expression index: "i"
Referential
boundary: The
target chemical should be classified as Non-covalent interaction OR
Non-covalent interaction >> DNA intercalation OR Non-covalent
interaction >> DNA intercalation >> DNA Intercalators with Carboxamide
Side Chain OR Non-specific OR Non-specific >> Incorporation into
DNA/RNA, due to structural analogy with nucleoside bases OR
Non-specific >> Incorporation into DNA/RNA, due to structural analogy
with nucleoside bases >> Specific Imine and Thione Derivatives OR
Radical OR Radical >> Radical mechanism via ROS formation (indirect) OR
Radical >> Radical mechanism via ROS formation (indirect) >> Hydrazine
Derivatives OR Radical >> Radical mechanism via ROS formation (indirect)
>> Nitroarenes with Other Active Groups OR Radical >> Radical mechanism
via ROS formation (indirect) >> Specific Imine and Thione Derivatives OR
SN1 OR SN1 >> Nucleophilic attack after diazonium or carbenium ion
formation OR SN1 >> Nucleophilic attack after diazonium or carbenium ion
formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic
attack after reduction and nitrenium ion formation OR SN1 >>
Nucleophilic attack after reduction and nitrenium ion formation >>
Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic substitution
on diazonium ions OR SN1 >> Nucleophilic substitution on diazonium ions
>> Specific Imine and Thione Derivatives OR SN2 OR SN2 >> SN2 attack on
activated carbon Csp3 or Csp2 OR SN2 >> SN2 attack on activated carbon
Csp3 or Csp2 >> Nitroarenes with Other Active Groups by DNA binding by
OASIS v.1.3
Domain
logical expression index: "j"
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 >> Unsaturated heterocyclic azo by DNA binding
by OECD
Domain
logical expression index: "k"
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 >> Formamides
OR Michael addition OR Michael addition >> P450 Mediated Activation to
Quinones and Quinone-type Chemicals 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 No
alert found OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion
Formation >> Aliphatic tertiary amines OR SN1 >> Nitrenium Ion formation
>> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Unsaturated
heterocyclic nitro by DNA binding by OECD
Domain
logical expression index: "l"
Referential
boundary: The
target chemical should be classified as Not bioavailable by Lipinski
Rule Oasis ONLY
Domain
logical expression index: "m"
Similarity
boundary:Target:
Cc1ccc(N=NC2C(C)=NN(c3ccccc3)C2=O)c(C)c1
Threshold=50%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization
Domain
logical expression index: "n"
Referential
boundary: The
target chemical should be classified as Aromatic compound AND Carbonic
acid derivative AND Carboxylic acid derivative AND Heterocyclic compound
by Organic functional groups, Norbert Haider (checkmol)
Domain
logical expression index: "o"
Referential
boundary: The
target chemical should be classified as Carboxylic acid derivative by
Organic functional groups, Norbert Haider (checkmol)
Domain
logical expression index: "p"
Referential
boundary: The
target chemical should be classified as Alkyl arenes AND Aryl AND Azo
AND Pyrazolone AND Unsaturated heterocyclic amine AND Unsaturated
heterocyclic fragment by Organic Functional groups
Domain
logical expression index: "q"
Referential
boundary: The
target chemical should be classified as Alkoxy by Organic Functional
groups
Domain
logical expression index: "r"
Parametric
boundary:The
target chemical should have a value of log Kow which is >= 4.84
Domain
logical expression index: "s"
Parametric
boundary:The
target chemical should have a value of log Kow which is <= 9.4
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (not sensitising)
- Additional information:
Various studieshas been investigated for the test chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) to observe the potential for skin sensitization to a greater or lesser extent. The studies are based on in vivo experiments in guinea pigs and humans for target chemical4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) and its structurally similar read across substanceEdaravone (CAS No:-89-25-8) and functionally similar read across substance C.I. Pigment Red 3(CAS No: 2425-85-6).The predicted data using the OECD QSAR toolbox has also been compared with the experimental data and summarized as below;
The skin sensitization potential of 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9)was estimated using OECD QSAR toolbox version 3.3 with log Pow as the primary descriptor. The chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9)was estimated to be not sensitizing to the skin of Pirbright White guinea pigs. Based on the estimated result 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) failed to induce skin sanitization effects and hence is considered to be not sensitizing to Pirbright White guinea pigs.
TheCosmetic Ingredient Review, CIR Expert Panel {Journal Of The American College of Toxicology, Volume 11, Number 4, 1992; Mary Ann Liebert, Inc., Publishers} conducted skin sensitizationstudy on20 guinea pigsfor read across chemicalEdaravone(CAS No:-89-25-8).In induction phase, 0.5ml of a 0.5% aqueous 3-methyl-1-phenyl-5-pyrazolone solution was applied dermally onclipped skin of left scapular regionfor 1hr under occlusive condition. This procedure was repeated 3 times in week for total 10 applications. After removal of patch the test site was rinsed with water. During the study, the guinea pigs received 2 intradermal injections of 0.1ml3freund’s complete adjuvant diluted to 50% with sterile isotonic saline near the test site.After 12 days rest period, animals were challenged at concentration of 0.50ml on clipped skin of left flank of abdomen using occlusive patch for 1 hour. After removal of patch, skin site was rinsed and observations were made after 1, 6, 24, 48 hrs.None of the animal produced any ski reactions at challenge concentration .Hence3-Methyl-1-Phenyl-5-Pyrazolonewas (CAS No:-89-25-8) was considered to be not sensitizing to the skin of albino guinea pigs.
The above results were further supported by patch test study of read across chemical C.I. Pigment Red 3 (CAS No: 2425-85-6) conducted by TAKEHITO KGZUKA et.al., {Contact Dermatitis;Volume6; Pg. no.330-336; 1980}. This skin sensitization study was performed in human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R.The patch of Toluidine Red was applied onto the back of each patient for24 hours by usingFinn Chambers® on Scanpor® (Epitest, Ltd. Oy) at a dose of 1% in petrolatum. After removal of patch, skin reactions were assessedaccording to the ICDRG classification for 2 days.Twenty-eight healthy female volunteers, aged 20 and 21, were also tested with the sample as controls. None gave a positive reaction.The negative skin sensitizing effects were observed in all treated patients. Thusthe test chemicalToluidine Red(CAS No: 2425-85-6)was considered to be not sensitizingin human patients suffering from pigmented contact dermatitis caused by the commercial Brilliant Lake Red R.
Thus on the basis of available data for thetarget chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) and its structurally similar read across substance Edaravone(CAS No:-89-25-8) and functionally similar read across substance C.I. Pigment Red 3 (CAS No: 2425-85-6),it can be concluded that chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) is unable to cause skin sensitization and considered as non-skin sensitizer. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Not Classified”.
Respiratory sensitisation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Justification for classification or non-classification
The skin sensitization potential of test substance 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) and itsstructurallysimilar read across substanceEdaravone(CAS No:-89-25-8) and functionally similar read across substance C.I. Pigment Red 3 (CAS No: 2425-85-6) were observed in various studies. From the results obtained from these studies it is concluded that the chemical 4-[(E)-2-(2,4-dimethylphenyl)diazen-1-yl]-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazol-5-one (CAS No: 6407-78-9) is not likely to cause skin sensitization and hence can be classified as non-skin sensitizer.
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