Procyanidin A1 is an

A type proanthocyanidin A type proanthocyanidins are a specific type of proanthocyanidins, which are a class of flavonoid. Proanthocyanidins fall under a wide range of names in the nutritional and scientific vernacular, including oligomeric proanthocyanidins, flavonoids ...

dimer. It is an

epicatechin Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical family derives from ''catechu'', which is the tannic ...

-(2β→7,4β→8)-

catechin Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids. The name of the catechin chemical family derives from ''catechu'', which is the tannic ...

dimer found in ''

Rhododendron spiciferum ''Rhododendron spiciferum'' (碎米花) is a rhododendron species native to western Guizhou and Yunnan, China, where it grows at altitudes of . It is a small evergreen shrub growing to in height, with leaves that are narrowly oblong or oblong-la ...

'', in

peanut The peanut (''Arachis hypogaea''), also known as the groundnut, goober (US), pindar (US) or monkey nut (UK), is a legume crop grown mainly for its edible Seed, seeds. It is widely grown in the tropics and subtropics, important to both small ...

skins and in ''

Ecdysanthera utilis ''Urceola micrantha'' is a plant species in the genus '' Urceola''. It is a shrub widespread across much of East Asia, Southeast Asia, and the Himalayas. In Taïwan, it is used in folk medicine as an analgesic, antiphlogistic and spasmolytic a ...

''.

Procyanidin B1 Procyanidin B1 is a procyanidin dimer. It is a molecule with a 4→8 bond (epicatechin-(4β→8)-catechin). Proanthocyanidin-B1 can be found in ''Cinnamomum verum'' (Ceylon cinnamon, in the rind, bark or cortex), in ''Uncaria guianensis'' (cat's ...

can be converted into procyanidin A1 by radical oxidation using

1,1-diphenyl-2-picrylhydrazyl DPPH is a common abbreviation for the organic chemical compound 2,2-diphenyl-1-picrylhydrazyl. It is a dark-colored crystalline powder composed of stable free radical molecules. DPPH has two major applications, both in laboratory research: one is ...

(DPPH) radicals under neutral conditions.Conversion of procyanidin B-type (catechin dimer) to A-type: evidence for abstraction of C-2 hydrogen in catechin during radical oxidation. Kazunari Kondo, Masaaki Kurihara, Kiyoshi Fukuhara, Takashi Tanaka, Takashi Suzuki, Naoki Miyata and Masatake Toyoda, Tetrahedron Letters, 22 January 2000, Volume 41, Issue 4, Pages 485–488,

References

Procyanidin dimers {{Aromatic-stub