purina

Noun

 * 1)  purine

Etymology
,, from.

Noun

 * 1)  purine: Any of a class of organic heterocyclic compounds, composed of fused pyrimidine and imidazole rings, that constitute one of the two groups of organic nitrogenous bases (the other being the pyrimidines) and are components of nucleic acids.

Usage notes
Although is standard form, the form  has been the dominant form.

Noun

 * 1)  purine

Noun

 * 1)  purine heterocyclic compound composed of fused pyrimidine and imidazole rings

Etymology
, from.

Noun

 * 1)  purine