ARTEMETHER, FIGHT AGAINST MALARIA
Artemether (INN) is an antimalarial for the treatment of multi-drug resistant strains offalciparum malaria. It is combined with Lumefantrine and sold by Novartis under the brand names Riamet and Co-Artem.
| step 1 was smooth , the reduction with sodium borohydride. Only the beta form was isolated due to its poor solubility in the quench. Drying the product without heat prevented formation of one byproduct. Moving on to step two, the methylation with HCl in methanol was more troublesome. The byproducts lurking around the corner are the anomer and the elimination product. Co-solvent (co-reagent?) trimethyl orthoformate made all the difference. The critical element in the workup was first adding more methanol before adding the base quench otherwise you end up with a nasty gum. The new record yield for the improved synthesis is 72%. |
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