1,2-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one

Independent reference data for 1,2-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one (CAS 19735-89-8), compiled from public chemistry databases.

Registry identifiers across databases

Computed descriptors

Physicochemical values on record

Documented uses on record

CIR ingredient: Phenyl Methyl PyrazoloneUsed as an intermediate for dyes and drugs, reagent to detect cyanide, and developer for diazotized direct dyes; [HSDB] Used in the treatment of strokes; [Merck Index] Used for synthesis in the chemical industry and in the textile processing industry; [IUCLID] Used in hair dyes; [ExPub: EC]

Synonyms and trade names

MCI-186; MCI 186; RefChem:57584; edaravone; 89-25-8; 3-METHYL-1-PHENYL-2-PYRAZOLIN-5-ONE; Radicut; Norphenazone; 1-Phenyl-3-methyl-5-pyrazolone; Developer Z; Methylphenylpyrazolone; Norantipyrine; C.I. Developer 1; Phenylmethylpyrazolone; Phenyl methyl pyrazolone; Radicava

Regulatory listings held on file

Regulatory & Food Contact	CIR / INCI: Cosmetic ingredients (Phenyl Methyl Pyrazolone) -> CIR (Cosmetic Ingredient Review) CIR / INCI: Hair dyeing
GHS notification summary	7.7% (16 / 209)

GHS hazard classification

GHS notification summary	7.7% (16 / 209)
Reported hazard statements	H302 (26.8%), H315 (34.4%), H317 (59.8%), H319 (23.4%), H335 (26.8%), H412 (52.2%)

This chemical does not meet GHS hazard criteria for 7.7% (16 of 209) of reports.

H302 (26.8%): Harmful if swallowed [Warning Acute toxicity, oral]

What the public record says

1,2-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one · CAS 19735-89-8 · C10H10N2O. UNII S798V6YJRP. Boiling Point: 549 °F at 105 mmHg (NTP, 1992); Boiling Point: 287; Boiling Point: 191 °C @ 17 MM HG; 287 °C @ 105 MM HG.

Physical description and handling notes

Source: PubChem / Wikidata; the batch COA governs where values differ.