Uridine Uridine Uridine is a glycosylated pyrimidine-analog containing uracil attached to a ribose ring (or more specifically, a ribofuranose) via a β-N-glycosidic bond. It is one of the five standard nucleosides which make up nucleic acids, the others being adenosine, thymidine, cytidine and guanosine. The five nucleosides are commonly abbreviated to their one-letter codes U, A, T, C and G respectively. However, thymidine is more commonly written as 'dT' ('d' represents 'deoxy') as it contains a 2'-deoxyribofuranose moiety rather than the ribofuranose ring found in uridine. This is because thymidine is found in deoxyribonucleic acid (DNA) and not ribonucleic acid (RNA).
Prephenic acid higher priority (according to CIP rules) on the two pseudoasymmetric carbons, "i.e." the carboxyl and the hydroxyl groups, in the "cis" configuration, or (1"s", 4"s") according to the new IUPAC stereochemistry rules (2013). The other stereoisomer, "i.e. trans" or, better, (1"r", 4"r"), is called epiprephenic. Prephenic acid Prephenic acid, commonly also known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine, as well as of a large number of secondary metabolites of the shikimate pathway. It is biosynthesized by a [3,3]-sigmatropic Claisen rearrangement of chorismate. Prephenic acid is an example