Definition of "purine" [purine]

• A double-ringed, crystalline organic base, C5H4N4, not known to occur naturally, from which is derived the nitrogen bases adenine and guanine, as well as uric acid as a metabolic end product. (noun)
• Any of a group of organic compounds structurally related to purine, particularly adenine and guanine, and also caffeine, uric acid, theobromine, and theophylline. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "They form phosphorus-containing organic substances which, together with a form of phosphoric acid, usually contain purine bodies, pyrimidine bodies and a form of sugar or related substance."
• "I started reading about Alzheimer's and tried to familiarize myself with the research, and at the same time when I was in the -- I was reading in the medical library one day, and I read this article about something called purine derivatives."
• "Uric acid levels are elevated when injesting too much purine, which is found in red meats, legumes, beer, and vegetables such as asparagus and"