Pyrocatechol


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Related to Pyrocatechol: resorcinol

Pyrocatechol

 

(o-dihydroxybenzene), a dihydric phenol; a colorless crystalline solid with a phenol odor. Melting point, 104°C; boiling point, 246°C. Darkens rapidly upon exposure to air; soluble in water, alcohol, and ether.

Pyrocatechol fuses with phthalic anhydride to yield the dyes alizarin and hystazarin. It is alkylated by isobutylene to tert-butylpyrocatechol, an effective inhibitor of free radical processes. Pyrocatechol is used as a photographic developer.

Pyrocatechol is found in the molecules of many native aromatic compounds (for example, tannins), from which it was first obtained by dry distillation. It is a source material in the preparation of adrenalin; the monomethyl ether of pyrocatechol is called guaiacol. Pyrocatechol is commercially prepared by alkaline fusion of o-chlorophenol or o-phenolsulfonic acid.

References in periodicals archive ?
Don Tested for Detection (*) Test performed Phenols ++ Phosphomolybdic acid test Tannins +++ Braemer's test Steroids and Terpenoids - Liebermann- Burchardt test Alkaloids - Dragendorff's test Anthraquinones +++ Borntrager test * -- = Absent; ++= Moderate; +++ = Abundant Table 2.Total phenolic compounds (as pyrocatechol equivalent), total flavonoids (as catechin equivalent) and total anthocyanin of T.
graecum tubers and leaves were expressed as microgram of pyrocatechol equivalent mg of extracts as shown in Table 1.
On access with oxygen it can cause oxidation of various aromatic compounds (pyrocatechol, tyrosine) and produce blackish-grey discolorations.
For example, 15-60 mg/l 2,3,4-trimethylphenol, 0-10 mg/l 2.4-dibutylphenol, 24-243 mg/l pyrocatechol were mentioned [69].
We measured TUP by the benzethonium chloride and biuret method with the Hitachi 917 analyzer and by the modified biuret and pyrocatechol violet dry-chemistry method with the Vitros 250 analyzer (Johnson & Johnson).
Allergic contact dermatitis has been reported and four allergenic compounds have been characterized as pyrocatechol derivatives, but not fully identified, from different extracts of this plant and from L.
Pyro, named after the photographic chemical pyrocatechol, first flew as a kitten tucked into the jacket of New Brighton-bred Mr Bird as he carried out top secret spying missions for the government over enemy territory.
On nearly all his flights,Bob had tucked inside his flying jacket,Pyro the ginger cat, named after the developing fluid pyrocatechol. One of Bob's favourite inventions was the Flying Jeep.
Then a chemical such as potassium hydroxide, ethylene diamine pyrocatechol, or hydrazine selectively etches the material.
Merdivan, "Use of pyrocatechol violet modified sodium dodecyl sulfate coated on alumina for separation and preconcentration of uranium(VI)," Journal of Radioanalytical and Nuclear Chemistry, vol.
The developed potentiometric method used as detector a Pt electrode transducer based on logarithmic dependence, which provided the antioxidant activity of several hydrosoluble antioxidants (ascorbic acid, pyrocatechol, pyrogallol, caffeic acid, chlorogenic acid, gallic acid, tannic acid, uric acid, l-cysteine, and Trolox).