Definition: The term "oxypurine" is a combination of two terms, Oxypurine and Purine. Oxypurine is a naturally occurring compound found in many plant-based foods like nuts, seeds, legumes, and some fruits. It's also known as purinylpyrimidine nucleoside, which means it contains the base of a nucleic acid called purinyl pyrimidine. Purine is a group of small organic molecules that are essential for DNA