- Anthocyanidins are common plant pigments. They are the sugar-free counterparts of anthocyanins based on the flavylium ion or 2-phenylchromenylium, which is a type of oxonium ion (chromenylium is referred also to as benzopyrylium). They form a large group of polymethine dye.
- In particular anthocyanidins are salt derivatives of the 2-phenylchromenylium cation, also known as flavylium cation.
- Anthocyanidins have flavylium cations, a lewis acid will interact with buckminsterfullerence which is a resonance and canonical structure as lewis basis.
- Among polyphenols, the anthocyanidins and their glycosylated derivatives, anthocyanins, abundantly present in pigmented fruits and vegetables.