Isocytosine or 2-aminouracil is a pyrimidine base that is an isomer of cytosine. It is used in combination with isoguanine in studies of unnatural nucleic acid analogues of the normal base pairs in DNA.[1] In particular, it is used as a nucleobase of hachimoji RNA.[2]

Isoguanine-Isocytosine-base-pair

It can be synthesized from guanidine and malic acid.[3]

Synthesis of isocytosine from malic acid

It is also used in physical chemical studies involving metal complex binding, hydrogen bonding, and tautomerism and proton transfer effects in nucleobases.[4]

Tautomerism of isocytosine

References

  1. ^ "Isocytosine". Molecule of the Week. American Chemical Society. Retrieved November 1, 2012.
  2. ^ Hoshika, Shuichi; et al. (22 February 2019). "Hachimoji DNA and RNA: A genetic system with eight building blocks". Science. 363 (6429): 884–887. doi:10.1126/science.aat0971. PMC 6413494. PMID 30792304.
  3. ^ William T. Caldwell , Harry B. Kime (1940). "A New Synthesis of Isocytosine". J. Am. Chem. Soc. 62 (9): 2365–2365. doi:10.1021/ja01866a028.
  4. ^ "Isocytosine". Sigma-Aldrich. Retrieved November 1, 2012.