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Related to Quinone: benzoquinone, quinine, hydroquinone


(organic chemistry)
CO(CHCH)2CO Yellow crystalline compound with irritating aroma; melts at 116°C; soluble in alcohol, alkalies, and ether; used to make dyes and hydroquinone. Also known as benzoquinone; chinone.



any one of a class of cyclic diketones in which both carbonyl (C=O) groups are in a system of conjugated double bonds. Quinones are obtained in the form of colored crystals, which have a sharp odor. For example, para-benzoquinone (I), with a melting point of 116°C, and 1,4-naphthoquinone (II), with a melting point of 128.5°C, are yellow, while ortho-benzoquinone (III), with a melting point of 70°–80°C (with decomposition), and anthraquinone are red (seeANTHRAQUINONE).

Various pigments in nature are derivatives of quinones; for example, muscapharin, the dye substance of the fly agaric, is a derivative of para-benzoquinone. Quinones are readily reduced to yield diatomic phenols [for example, in industry, hydroquinone is obtained from (I) in this way]. They actively enter in diene synthesis,

as well as form molecular complexes with phenols. They are used in analytical chemistry.

Quinones are obtained by several methods, including the oxidation of the aromatic hydrocarbons or of their hydroxy or amino derivatives; for example, (I) is obtained by the oxidation of aniline, while (II) and anthraquinone are obtained by the oxidation of naphthalene and anthracene, respectively. Quinones and their derivatives are intermediate products in the production of dyes (seeANTHRAQUINONE DYES). They are also used as fungicides, insecticides, and tanning agents. 2-Methyl-1,4-naphthoquinone is a vitamin of the vitamin K group.

References in periodicals archive ?
Pyrroloquinoline quinone against glutamate-induced neurotoxicity in cultured neural stem and progenitor cells.
There has been a growing interest in the electrochemistry of quinones, substituted quinones and nitroarenes, and their electrochemically reduced products - anion radicals and dianions [1-6].
Pyrroloquinoline quinone stimulates mitochondrial biogenesis through cAMP response elementbinding protein phosphorylation and increased PGC-lalpha expression.
Similar results were obtained with 1,2-naphthaquinone, whereas a nonredox-cycling quinone, AQ, was inactive (not shown).
Synthetic poly(isoprene) was oxidized in the presence of quinone diimines.
Pyrroloquinoline quinone stimulates mitochondrial biogenesis through cAMP response element-binding protein phosphorylation and increased PGC-1a expression.
Rombaon topped the Women Open race while national team mainstays Mellisa Jaroda and junior rider Nicole Quinones placed third and fourth, respectively, aboard their Methanol CV and Methanol SX bikes.
Albano said Moreno and Quinones were the first government employees in town to be caught inside a gambling establishment in violation of President Rodrigo Duterte's directive last week banning government workers from all gambling facilities like casinos-part of a crackdown on public servants with lavish lifestyles.
Now Quinones is passionate about today's young people being given that same opportunity.
Although Goffner copped the C title, he bowed in the B semifinals to Luis Quinones in a competitive 21-15, 21-17 contest.
SPEX) Managing Director Sebastian Quinones noted that "there will be a commercial discussion"; but the timeline on the negotiations must be signaled by government via the Department of Energy.