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Clinical pharmacy PharmD program                     Third level                          Phytochemistry-1 (PG-504)


                                2. Flavonol Glycosides Ex.: Rutin - Quercetrin




              These two glycosides are of wide distribution in many plant genera.


                                                  OH           Quercetin  : R = H

               HO               O                              Quercetrin : R = rhamnosyl
                                                      OH
                                                               Rutin : R = rhamno-glucosyl

                                                                                     (rutinosyl)
                                       OR
                                O
                      HO


                 •  Rutin is the 3-rhamnoglucoside of the genin quercetin.

                 •  It gives on hydrolysis the aglycone (quercetin) and one molecule of glucose, and
                     one molecule of rhamnose.


                 •  The glycoside quercetrin, is quercetin, 3-O-rhamnoside.

                 •  The disaccharide moiety of rutin (rhamno-glucose) is known as rutinose; which
                     is of common occurrence in glycosides of family rutaceae.


















          •  Quercetrin is obtained from Quercus tinctoria.

             The aglycone quercetin occurs in free state in bearberry leaves (Uva Ursi) and   contributes to the
           diuretic action of leaves.

       Uses:

       Rutin decrease the capillary fragility (increase tensile strength of capillary walls)


       and reduce capillary permeability induced by histamine or by tissue injury,

        so they are used in certain disease-condition to reduce capillary bleeding.



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