Genistein chemical structure

Fig. 2.86. Chemical structures of the iosflavones daidzein, genistein, O-desmethylangolensin, equol, and the lignans enterolactone and enterodiol. Reprinted with permission from Z. Kuklenyik el al. [209].

FIGURE 7.2 Chemical structures of the main soy (genistein and daidzein) and red clover (biochanin A and formononetin) isoflavonoids (aglycones and glucosides). 

As previously mentioned, certain flavonoids can penetrate into the hydrophobic core of membranes, a feature that mainly relies on their hydrophobic character, which is dictated by flavanoid chemical structure and spatial conformation. When flavonoid hydrophobicity was assessed from the partition coefficient between ra-octanol and an aqueous solution, the following order of hydrophobicity was observed flavone, genistein > eriodictyol, myricetin, quercetin, kaempferol, hesperetin, daidzein > > galangin, morin, flavanone, naringenin, taxifolin (Table 4.1). 

Fig. 8.5 Chemical structures of EDCs (a) bisphenol-A (b) triclosan (c) nonylphenol (d) 17b-estradiol (e) genistein (f) b-sitosterol...

Chemical structures of flavonoids. These flavonoids consisted of three groups flavone (apigenin and lutolin), flavonols (flavonol, kaempferol, quercetin, myricetin, tangeretin, and nobiletin) and isoflavones (daizein, genistein, biochanin A, and equol). 

Figure 1 Chemical structures of two major isoflavones and an estrogen. The structures of genistein (4H-henzopyran-4-one-5, 7-dihydroxy-3-(4-hydroxyphenyl) or 4, 5,7-trihy-droxyisoflavone), daidzein (4H-henzopyran-4-one-7-hydroxy-3-(4-hydroxyphenyl) or 4, 7-dihydroxyisoflavone), and estradiol are shown. The purification schemes of the isoflavones and their physical properties are reported in Ref. 98.

Figure 8.1 A diagram t)T ihc chemical structures of the isoflavone aglycones found in soybean as well as conjugates of daidzein. Similar conjugates arc fornicd of genistein and glycitein.

The most important members of the flavonoid family include anthocyanidins (e.g., cyanidin, delphinidin, malvidin), flavonols (e.g., quercetin, kaempferol), flavones (e.g., luteolin, apigenin), flavanones (e.g., myricetin, naringin, hesperetin, naringenin), flavan-3-ols (e.g., catechin, epicatechin, gallocatechin) and, although sometimes classified separately, the isoflavones (e.g., genistein, daidzein). For chemical structures see Figure 1. All these phytochemical are frequently referred to as bioflavonoids due to well established effects in human health maintenance. 

Figure 3. Chemical structures of daidzein, genistein, resorcinol and resveratrol. All agents have a common resorcin moiety, except for daidzein,...

As for flavones, or isoflavones, mentioned previously, the prefix iso- signifies a similarity or, more exactly, the same chemical composition but a different structure, with different physical and chemical properties. According to a letter and litraature search presented by Sally Fallon and Mary G. Enig in the July 2004 Townsend Letter for Doctors Patients, cited elsewhere, the soy isoflavone genistein has been found to act as an inhibitor for tyrosine kinase. However, it has also been found to damage the DNA and to have adverse estrogen-like effects. Apparently, there is a trade-off. 

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