Aglycones chemical structure

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

Figure F1.1.2 Structural and spectral characteristics of the major naturally occurring aglycons. The chemical structure indicates the two aromatic rings (A, B) as well as the R1 and R2 substitution sites.

Currently over 50 betacyanins have been identified, but most of them are based on the two isomeric aglycones betanidin and isobetanidin (the C15 epimer of betanidin), whose chemical structures are shown in Fig. 19. According to the formula for betanidin, there are two asymmet-... 

The basic chemical structure of anthocyanidins (aglycone) is shown in Figure 5.1. Over 600 naturally occurring anthocyanins have been... 

The metabolites isolated from medicinal plants have a wide variety of chemical structures but complex polar structures such as glycosides of triterpene, steroidal and flavonoid aglycones are of particular interest. 

The commercial product is erythromycin A. which differs from its bio.syntlietic precursor, erythromycin B, in having a hydroxyl group at the 12 position of the aglycone. The chemical structure of erythromycin A was reported by Wiley et al. in I9.S7 and its stereochemistry by Celmer in 1965. An elegant synthesis of erythronolidc A, the aglycone pre.sent in erythromycin A. wa.s described by Corey and associates. ... 

Recently, we have reviewed for the first time the chemical structures of sea cucumber glycosides and the principal spectral features of the aglycones and oligosaccharide chains in their H- and C-NMR spectra [55]. Most of these triterpenoid oligoglycosides contain an aglycone... 

The ubiquitous flavonoids may be cited as an example of the manifold factors affecting the bioavailability of phytochemicals thus, the bioavailability of flavonoids differs between food sources, predominantly due to the nature of the attached sugar(s). The chemical structure (glycoside or aglycone) of a phytochemical will affect intestinal absorption and first-pass metabolism and will, therefore, modulate its pharmacokinetics [4,6]. 

T] values are of interest in polysaccharides since they reflect the chemical structure of the molecule. In stachyose (Fig. 22), the values reflect greater segmental motion at the ends of the molecule (43). However in a trisaccharide of a ganglioside the -acetyl-neuraminic acid acts as an anchor (44), similar to the bulky aglycone portion of the ic-strophanthoside where the T- values of the cymarose portion are lower then those of successive g-g-glucopyranose units (45). 

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.

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