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purine pu·rine (pyur'ēn')
A colorless crystalline organic base that is the parent compound of various biologically important derivatives.
Any of a group of organic compounds that are derived from or are structurally related to purine, including uric acid, caffeine, adenine, and guanine.
Any of a group of organic compounds containing two fused rings of carbon and nitrogen atoms. One ring has six members, the other has five, and each has two nitrogens. Purines include a number of biologically important compounds, such as adenosine, caffeine, uric acid, and the two bases adenine and guanine, which are components of DNA and RNA.