Orotidine, a nucleotide, is an intermediate in pyrimidine nucleotide biosynthesis in RNA and DNA. Orotidine is mainly found in bacteria, fungi and plants.

Extant de novo biosynthetic pathway uses Orotidine 50-monophosphate to synthesize the canonical pyrimidine nucleotides in RNA and DNA. In this context, Orotidine is the only nucleotide that is synthesized through a ‘direct intermolecular nucleosidation’ step, with an attack of the fully-preformed nucleobase (orotic acid) on the activated 5-phosphoribosyl-diphosphate as opposed to the purine nucleotides whose heterocyclic rings are constructed stepwise on the sugar.

西域 has not independently confirmed the accuracy of these methods. They are for reference only.

• . Kim EK, et al. Synthesis of orotidine by intramolecular nucleosidation. Chem Commun (Camb). 2015 Apr 4;51(26):5618-21.  [Content Brief]

  . A M MICHELSON, et al. A new ribose nucleoside from Neurospora; "orotidine". Proc Natl Acad Sci U S A. 1951 Jul;37(7):396-9.  [Content Brief]