pyrazole

/pir"euh zohl', -zawl'/, n. Chem.

1. any of the group of heterocyclic compounds containing three carbon atoms, two adjacent nitrogen atoms, and two double bonds in the ring.

2. the parent compound, C₃H₄N₂.

[1885-90; PYR- + AZOLE]

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▪ chemical compound

      any of a class of organic compounds of the heterocyclic series characterized by a ring structure composed of three carbon atoms and two nitrogen atoms in adjacent positions. The simplest member of the pyrazole family is pyrazole itself, a compound with molecular formula C₃H₄N₂.

      The pyrazole compounds are not known to occur in nature; they are usually prepared by the reaction of hydrazines with 1,3-diketones. Many synthetic pyrazole compounds are of importance as dyes and medicinals. Among them are: antipyrine, used as an analgesic and febrifuge; tartrazine, most commonly used as a yellow dye for food; phenylbutazone (Butazolidin), an anti-inflammatory drug used in treatment of arthritis; and a series of dyes used as sensitizing agents in colour photography.

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