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benzoquinone
benzoquinone n. 
/ˌbɛnzəʊkwᵻˈnəʊn/, /ˌbɛnzoʊˈkwɪˌnoʊn/ either of two isomeric yellow crystalline compounds, having a structure similar to benzene but with two hydrogen atoms replaced by oxygen atoms to form carbonyl groups; (also) any substituted derviative of these; also called quinone.Formula: C6H4O2.
Brit. /ˌbɛnzəʊˈkwɪnəʊn/
, /ˌbɛnzəʊˈkwɪnəʊn//ˌbɛnzəʊkwᵻˈnəʊn/U.S. /ˌbɛnzoʊkwᵻˈnoʊn/
, /ˌbɛnzoʊkwᵻˈnoʊn//ˌbɛnzoʊˈkwɪˌnoʊn/ΚΠ
1888 Science 13 Jan. 20/1 (title) On carboxylated derivatives of benzoquinone.
1951 I. L. Finar Org. Chem. I. xxvii. 713 The yellow colour of p-benzoquinone is due to the presence of the quinonoid structure.
1990 Carcinogenesis 11 1349/1 The carcinogenicity of benzene has be considered to be in part mediated by its chemically reactive metabolic product benzoquinone.
2003 New Scientist 6 Sept. 22/2 The millipedes secrete toxic chemicals called benzoquinones, apparently to fend off predators.
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