A- and B-Glycosides

Both procedures for selective syntheses of 2,6-dideoxy-a- and B-glycosides will be outlined in the aure-olic acid and also the anthracycline oligosaccharide series. 

Contains up to about 8% triticin (a finctosan) 2-3% inositol and mannitol 1.5% fixed oil vitamins A and B glycosides (e.g., vanillin glucoside) mucilaginous substances ash with high silicon and iron contents and small amount of volatile oil (up to ca. 0.05%) among others (list and horhammer). ... 

The a- and B -glycosides (39) have been individually prepared as substrates for a glycosiduronase.Hydrogenation of the enal (40) gave mainly the L-arabino-aldehyde which could be epimerized in al]fali to the D-xylo-analoque. Reduction of (40) with surprisingly poor yielding and the hydroxymethyl product afforded... 

Vongvanich N, Kittakoop P, Kramyu J, Tanticharoen M, Thebtaranonth Y. Phyllan-thusols A and B, cytotoxic norbisabolane glycosides from Phyllanthus acidus Skeels. J Org Chem 2000 65 5420-5423. 

Yoshikawa M, Murakami T, Ueno T, Kadoya M, Matsuda H, Yamahara J, Murakami N. (1995) Bioactive saponins and glycosides, i. senegae radix. (1) E-senegasaponins a and b and z-senegasaponins a and b, their inhibitory effect on alcohol absorption and hypoglycemic activity. Chem Pharm Bull 43 2115-2122. 

Figure 2. Maps of the minimized energy (levels differ by. 5 kcal mol ) of the Ig Ag dimer as a function of the glycosidic torsion angles with the IdoA ring in (a) and (b) form, respectively.

Figure 5. Intersaccharide hydrogen bonds (dotted lines) and the glycosidic angle 0 (05-01-04 -04 ) between site A and B. These hydrogen bonds and 0 (= -86 ) are similar to those found for cellulose.

That which is usually extracted from both types of Digitalis is made up of already partially hydrolyzed glycosides. Purpureaglycoside A and B are natural glycosides contained in Digitalis purpurea that are broken down by enzymes into digitoxin and glucose, or... 

The main remit of this chapter is to provide reference and plant source details of new flavone and flavonol 0-glycosides discovered since 1991, i.e., covering the years 1992 to 2003. A checklist of all (as far as possible) known structures is also included in Appendices A and B. A series of reviews, which include most of the data on new 0-glycosylflavones and flavonols presented here, have appeared in Natural Product Reports and cover the years 1992 to 1994, 1995 to 1997, and 1998 to 2000, and with a fourth (2001 to 2003) " in press. Other useful sources of data are The Phytochemical Dictionary,The Handbook of Natural Flavo-noids, and for general background reading Jeffrey Harborne s Comparative Biochemistry of the Flavonoids. 

N.A. Purpurea-glycosides A and B, digoxin, digitoxin, caffeic acid, lanatoside, choline, saponins, chlorogenic acid.100 Improving blood circulation to the kidneys, it has cardiologic effect. 

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