A yellow, crystalline, heteroaromatic compound with a bicyclic molecular structure; any substituted derivative of this, many examples of which occur naturally, especially as insect pigments and vitamins of the B group.
Pteridine has a bicyclic molecule with fused pyrazine and pyrimidine rings. Formula: C₆H₄N₄.
1940s. From pter- + -idine, after German Pteridin.