catechol

from The Collaborative International Dictionary of English v.0.48

Pyrocatechin \Pyr`o*cat"e*chin\, n. [Pyro- + catechu.] (Chem.)
   A white crystalline substance, {C6H4(OH)2}, of the phenol
   series, found in various plants; -- so called because first
   obtained by distillation of gum catechu. Called also
   {catechol}, {oxyphenol}. etc.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

catechol \cat"e*chol\ (k[a^]t"[e^]*k[add]l`), n. [.]
   any of a group of chemicals having a benzene ring substituted
   with two hydroxyl groups in ortho position, especially
   ortho-dihydroxybenzene itself ({C6H6O2}), also called
   {pyrocatechol}, used in photography and as a reagent.
   [PJC]

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