Prodelphinidin trimers

Qa dan, F., Petereit, F., and Nahrstedt, A., Prodelphinidin trimers and characterization of a proanthocyanidin oligomer from Cistus albidus, Pharmazie, 58, 416, 2003. 

The limited numbers of new propelargonidins are listed in Table 11.7. This is in addition to the mixed procyanidin-propelargonidin tetramer, davallin (Table 11.5), " the mixed propelargonidin-procyanidin trimer, epiafzelechin-(4(S 8)-epicatechin-(4(S 8)-catechin (Table 11.5), and the mixed propelargonidin-prodelphinidin-procyanidin pentamer... 

Catechin and the proanthocyanidin prodelphinidin B3 are, respectively, the major monomeric and dimeric flavan-3-ols found in barley and malt where prodelphinidin B3 is the main contributor for the radical scavenging activity [Dvorakova et al., 2007], Proanthocyanidins have also been detected in nuts. Hazelnuts (Corylus avellana) and pecans (Carya illinoensis) are particularly rich in proanthocyanidins containing ca. 5 g kg, whereas almonds (Prunus dulcis) and pistachios (Pistachio vera) contain 1.8-2.4 mg kg 1, walnuts (Juglans spp.) ca. 0.67 g kg, roasted peanuts (Arachis hypgaea) 0.16 g kg, and cashews (Anarcardium occidentale) 0.09 g kg 1 [Crozier et al., 2006c]. Dark chocolate derived from the roasted seeds of cocoa (Theobroma cacao) is also a rich source of procyanidins [Gu et al., 2004], Monomeric flavan-3-ols and the proanthocyanidin B2, B5 dimers, and Q trimer are found in fresh cocoa beans (Fig. 1.13). Flavan-3-ols have also been detected in mint... 

Flavan-3-ols are widely distributed in the Filicopsida and are almost invariably accompanied by condensed tannins. Several flavan-3-ol glycosides (389-394) have been isolated from ferns (202, 207, 240, 241). Dryopterin (280) found in Dryopterisfilix-mas is a new type of flavan-3-ol which contains an additional a-pyrone ring (181). Trimeric proanthocyanidins, arachnitannins 1 (282), 2 (283) and 3 (284), which contain dryopterin as the terminating unit were isolated from Arachniodes species (183). Proanthocyanidin polymers from Cyathea dealbata are composed of procyanidin and prodelphinidin in the ratio 6 4 (251). 

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