- Preparation method of granisetron intermediate
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The invention discloses a preparation method of a granisetron intermediate. The preparation method comprises the following steps: step 1, carrying out a Mannich reaction on acetone dicarboxylic acid represented by a formula III to obtain pseudopelletierine represented by a formula IV; step 2, carrying out a reaction on the pseudopelletierine and hydroxylamine to prepare 3-pseudopelletierine oximerepresented by a formula V; and step 3, carrying out preparation by adopting one of the following schemes: (1) carrying out catalytic reduction on the 3-pseudopelletierine oxime through sodium bis(2-methoxyethoxy)aluminumhydride and Lewis acid to obtain a crude product of endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane represented by a formula I, and directly using the crude product of endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane to prepare granisetron, or purifying the crude product of endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane for preparing granisetron; and (2) carrying out catalytichydrogenation reduction on the 3-pseudopelletierine oxime through Raney nickel to obtain a mixture of endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane, purifying the mixture to obtain endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane represented by the formula I, and using the endo-3-amine-9-methyl-9-azabicyclo[3,3,1]nonane used for preparing granisetron. The method has the advantages of mild reaction conditions, high reaction yield and low cost, and is suitable for industrial production.
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- Benzoxazole carboxamides for treating CINV and IBS-D
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Compounds of formulae I and II: are disclosed as 5-HT3 inhibitors. Those compounds that exhibit central activity are useful in treating CINV; those that inhibit peripheral receptors are useful to treat IBS-D.
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Page/Page column 7
(2008/06/13)
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