Flavonoid Isoflavonoid

N.A. Triterpene saponins, chalcones flavonoids, isoflavonoids.99 312-511 Sweet-tasting tonic, treat sore throats, wheezing, coughs, canker sores, peptic ulcer, and gastritis. 

The phenolics include anthocyanins, anthraquinones, benzofurans, chromones, chromenes, coumarins, flavonoids, isoflavonoids, lignans, phenolic acids, phenylpropanoids, quinones, stilbenes and xanthones. Some phenolics can be very complex in structure through additional substitution or polymerization of simpler entities. Thus xanthones can be prenylated and flavonoids, lignans and other phenolics can be glycosylated. Condensed tannins involve the polymerization of procyaninidin or prodelphinidin monomers and hydrolysable tannins involve gallic acid residues esterified with monosaccharides. As detailed in this review, representatives of some major classes of plant-derived phenolics are potent protein kinase inhibitors. 

Harrison M.H., Dixon R.A. Spatial patterns of expression of flavonoid/isoflavonoid pathway genes during interactions between roots of Medicago truncatula and the mycorrhizal fungus Glomus versiforme. Plant J 1994 6 9-20. 

Type 1 MTs, currently exclusive for oxygen atoms (OMTs), methylate hydroxyl moieties of phenylpropanoid-based compounds (Fig. 2.3). The phenylpropanoid scaffold is used as a building block for many other types of compounds in the plant. Modification of this basic unit by multiple condensation reactions yields chalcone, flavonoid, isoflavonoid, and pterocarpan skeletons, for example. Flavonoids are ubiquitous in higher plants, where they function as UV protectants,5 defense compounds,6 and stimulators of beneficial mutualistic interactions with microorganisms, insects, and other organisms.7 Isoflavonoid natural products are limited primarily to leguminous plants, where they function as pre-... 

The polyphenols are a series of phytochemicals synthesized by plants. They include the bioflavonoids anthocyanins, coumestanes, flavonoids, isoflavonoids, and stil-benes (Figure 4.1). Each bioflavanoid class is subdivided into other groups, e.g., flavones, flavans, flavanols, flavonols, and flavanones (Figure 4.2). Another class of polyphenol is the oligomeric polyphenols, such as the proanthocyanidins, found in the grape and various berries (black currant, blueberry, etc.). 

Grisebach, H., and W. D. Ollis Biogenetic Relationship Between Coumarins, Flavonoids, Isoflavonoids, and Rotenoids. Experientia 17, 4 (1961). 

The second class of flavonoids, isoflavonoids, possesses a 3-phenylchroman (3) skeleton that is biogenetically derived by 1, 2-aryl migration in a 2-phenylchroman... 

Fig. 53.5 Biosynthetic pathways engineered in S. cerevisiae for the production of varieties of flavonoids, isoflavonoids, and stilbenes...

Dalbergia odorifera Heartwood Flavonoids, isoflavonoids ESI(-) Liu etal, 2005... 

Medicago truncatula Root and cell culture Flavonoids, isoflavonoids (glycosides) ESI( ) Farag / al., 2007... 

Sophora flavescens Root Flavonoids, isoflavonoids ESI (H-) Zhang et al, 2007... 

Phytoalexins are low molecular weight products which are produced in response to elicitors such as microbial, herbivorous or environmental stimuli (Poulev et al. 2003). Once plants detect a pathogen signal, a complex mixture of secondary metabolites is produced to control the invader. These molecules are synthesized de novo, and thus involve the activation of certain genes and enzymes required for their synthesis (Kuc 1995). Phytoalexins are chemically diverse and may include many chemical classes such as simple phenylpropanoid derivatives, alkaloids, gly-costeroids, flavonoids, isoflavonoids, various sulphur products, terpenes and polyketides (Hammerschmidt 1999). There is no boundary between phytoalexins and phytoanticipins, and in one plant species a certain chemical can function as a phytoalexin, whereas it has the function of a phytoanticipin in another species (Junghanns et al. 1998). It is important to point out that the distinction between phytoanticipins and phytoalexins is not based on their chenucal structure but rather on how they are produced. Thus, the same chemical may serve as both phytoalexin and phytoanticipin, even in the same plant (VanEtten et al. 1994). 

The structures of many of the naturally occurring flavonoids, isoflavonoids and neoflavonoids contain Cj units which are apparently derived from mevalonate the precursor of the isoprenoid units of terpenes and steroids. The biosynthetic processes in which the additional units are incorporated into the structures of these compounds presumably involved the intervention of yy-dimethyl-allylpyrophosphate or isopentenylpyrophosphate as intermediates . An additional, and rather unusual structural variation, which has recently been encountered is that of the flavonolignan class in which a flavonoid (taxifolin) is apparently condensed with a pbenylpropanoid intermediate (coniferyl alcohol) . Typical examples of the various classes and the considerable structural diversity which is to be found within them are shown in the accompanying formulae (13-33). 

Astaxanthin Other carotenoids Phytic acid Flavonoids Isoflavonoids Other phenols Organosulfur compounds Constituents of herbs and spices... 

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