purine
Concise Oxford English Dictionary © 2008 Oxford University Press:
purine /ˈpjʊəriːn/
▶noun Chemistry a colourless crystalline bicyclic compound with basic properties.
■ (also purine base) a substituted derivative of this forming one of the two classes of base present in DNA and RNA, including adenine and guanine.
– origin C19: from Ger. Purin, from L. purus ‘pure’ + uricum ‘uric acid’ (which it forms on oxidation) + -ine4.
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