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




           The most widely used drugs that contain anthracene derivatives are             :


                           1-  Senna Leaves and Pods.
                           2- Cascara Bark: Contains: cascarosides A, B, C and D
                           3- Frangula Bark: It contains the glycosides frangulin and glucofrangulin.
                           4- Aloes: It contains the C-glycosides mainly barbaloin. The C-linked glucose at C-
                                    10 protect anthrones from oxidation.

                           5- Rhubarb rhizome:  The presence of tannins in rhubarb makes the drug
                             constipating.  So, in small doses, rhubarb exerts no purgative action but acts only
                             as intestinal astringent, but large doses cause purgation.




               Warning:

                     Contra indicated in pregnancy and lactation

                     Prolonged use induces hypokalemia, potentiate the action of cardiac glycosides



                                                 4- Flavonoid Glycosides


             Flavonoidal compounds are considered as the largest group of naturally occurring phenols.

             Flavonoids also constitute the majority of the   yellow   colored plant pigments .

             They are all derived from 2-phenyl-benzopyran (Flavan).























           They are all derived from 2-phenyl-benzopyran (Flavan) and classified: according to the
             oxidation level, and/or the oxygenation of the central pyran ring, into:





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