Beans are high in purines, which are metabolized to uric acid. Adenine and guanine are purines, cytosine and uracil are pyrimidines. In humans, uric acid is the final step in the catabolic pathway of purines. Adenine and guanine are the two nucleotides classified as purines. Murexide test is a color test for uric acid and some other purines. The nucleobases are divided into purines (guanine and adenine) and pyrimidines (cytosine, thymine and uracil). Folates are also essential for the biosynthesis of purines and one pyrimidine. Foods high in the purines adenine and hypoxanthine may be more potent in exacerbating hyperuricemia. The complementary nitrogenous bases are divided into two groups, pyrimidines and purines. These bases are heterocyclic rings containing nitrogen, classified as purines or pyrimidines. Gout may be secondary to sleep apnea via the release of purines from oxygen-starved cells. Nucleotides can be separated into purines and pyrimidines. Folate derivatives participate in the biosynthesis of both purines and pyrimidines. Many organisms have metabolic pathways to synthesize and break down purines. Nucleotides may be divided into two categories&colon; purines and pyrimidines.