Flavones isovitexin

Avenanthramides, phenolic acids (esters, glycosides), tocopherols, flavonoids, phospholipids Flavones (isovitexin), phenolic acids (esters, glycosides), tocopherols Tocopherols, isoflavones and their glycosides, phenolic acids, phospholipids Lignans and their degradation products... 

Mahlin, J.A., Jung, K.H., and Schmidt, R.R., Glycosyl imidates, synthesis of flavone C-glycosides vitexin, isovitexin and isoembigenin, Liebigs Ann. Chem., 3, 461, 1995. 

Isovitexin (= Apigenin 6-C-glucoside) (flavone C-glycoside) Widespread Vitex lucens (Verbenaceae) ACE (46% inhibition at 763 pM) [78]... 

Flavonoids are widely distributed in many groups of plants. Viljoen et al., 49) showed that flavonoids occur as major compounds in 31 Aloe spp. out of the 380 studied. Four major flavonoids were detected in aloe naringenin (flavanone), dihydroisorhamnetin (dihydroflavonol) and aspienin and isovitexin (flavones). Moreover, the distribution of the different flavonoids provides valuable chemotaxonomic evidence 49). 

Fig. I6A A methanoiic extract of Lespedezae herba (4) contains more highly glycosidated flavonoids (R, range 0.05-0.35) such as kaempferol- and/or isorhamnetin-rhamno-glucoside and rutin (Tl). The EtAc extract (5,6) contains the enriched yellow zones of flavon-C-glyco.sides such as isoorientin (R, -- 0.S/T3), orientin (R, — 0.65/T3) overlapped by isovitexin, a.s well as flavonol-O-glycosides such as lespedin, hyperoside, isoquerdtrin and querdtrin (Rf 0.6-0.8).

Pereira, C.A.M., Yariwake, J.H., and McCuUagh, M. 2005. Distinction of the glycosyl-flavone isomer pairs orientin/isoorientin and vitexin/isovitexin using HPLC-MS exact mass measurement and in-source CID. Phytochem. Anal. 16 295-301. 

Sakamoto, Y. (1969) Flavones in green tea. Part II. Identification of isovitexin and saponarin. Agric. Biol. Chem., 33, 959-961. 

The mechanism of biosynthesis of flavone C-glycosidcs still remains obscure, but an isomerase which will convert isovitexin (39) into vitexin (40) has recently been detected in the Reporter s laboratory. It occurs in the grass Briza media, which contains glycoflavones, and it operates in only the one direction, the pH optimum being about 6.8. 

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