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


                     Desoxysugar or deoxysugars, in which one or more of the hydroxyl groups

              of  the  corresponding  aldose  or  ketose  has  been  replaced  by  hydrogen,  occur

              widely throughout nature. They are formed from the parent sugar by the removal

              of an oxygen atom from either a secondary or a primary alcohol group, to produce

              a (-CH 2-) or a (CH 3) group, respectively. They are more reactive than the parent

              sugar.


                 They are classified into:



              a)  2-Desoxy-hexoses.   b)  6-Desoxy-hexoses.   c)  2, 6-Didesoxy-hexoses.


                 a) 2-Desoxy-sugars = 2-desoxy-pentoses


              They are monosaccharides in which -OH group at C-2 has been replaced by H



              Importance and Example: 2-deoxy ribose: the sugar found in DNA






















              a)   6-Desoxy - sugars


                     The removal of an oxygen atom from the  terminal -CH 2OH group of a

              hexose, gives rise to 6-desoxy-sugar, which are regarded and named as methyl

              pentose. 6-desoxyhexose, such as L-fucose, L-rhamnose, and D-digitalose are

              found in many polysaccharides, and plant glycosides.








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