Biflavones amentoflavone

Biflavones Amentoflavone Bilobetin Ginkgetin Isoginkgetin Sciadopitysin 5 -methoxybilobelin... 

Rhus pyroides Burch, (syn. Rhus tridentata) (leaves) Biflavones. Amentoflavone (1) agathisflavone (100). Traditionally used in South Afriea for the treatment of epilepsy. Affinity for the GABAy benzodiazepine receptor. Svenningsen et ah, 2006[132]. 

Gymnospermae (leaf exudates) (epicuticular material of a number of species). Biflavones amentoflavone (1) bilobetin (3) podocarpusflavone A (6) sciadopitysin (15) cupressuflavone (86). Bilobetin is an active leishmanicidal compound. Wollenweber et al., 1998[431] Weniger et al., 2006[86]. 

Taiwania cryptomerioides Hayata (leaves) Biflavones Amentoflavone (1) hinokiflavone (235) taiwaniaflavone (189) II-7-O-methyltaiwaniaflavone (190) I-4, II-7-di-0-methyltaiwania-flavone (191) I-2,3-dihydrohinoki-flavone (241) 1-2,3-dihydroamentoflavone (31) 1-7-0-methyl-I-2,3-dihydroamentoflavone (32) podoearpusflavone A (6) sequoiaflavone (2). Gadek and Quinn, 1985[452], 1989[466]. 

Podocarpus latifolius (Thunb.) R. Br. ex Mirb. (leaves) Biflavones Amentoflavone (1) I-7,4 -di-O-methyl-amentoflavone (= ginkgetin) (7) heveaflavone (18) I-7,4, II-7,4 -tetra-O-methylamentoflavone (19). Used in Zulu traditional medieine. Ginkgetin is an aetive leishmanicidal compound. Ginkgetin also showed a good antitrypanosomal activity. Antimicrobial activity. Fozdar et al., 1989[483] Abdillahi et al., 2008[484], 2010[485]. 

Colovic, M. Fracasso, C. Caccia, S., Brain-to-plasma distribution ratio of the biflavone amentoflavone in the mouse, DrugMetab. Lett., 2008, 2, 90-94. 

Unfortunately, there is no commonly accepted trivial nomenclature for these compounds their full systematic names, not to mention their often complex common names, are extremely cumbersome. Geiger and Quinn have proposed a new system (125) but it, like the trivial procyanidin nomenclature initiated by Weinges (381), requires frequent reference for understanding and has become very difficult to use as the number of new compounds has grown. Locksley (232) has proposed a system in which the position of substitution of the upper (I) and lower (II) units is defined from the usual numbering of the parent flavonoid, and each unit is also described from the parent monomer. Thus, the common biflavone amentoflavone is named apigeninyl-(I-3, II-8)-apigenin, etc. Locksley s nomenclature is used in this chapter (232). 

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