Oxazole and Isoxazole Alkaloids

Triumferol or 4-hydroxyisoxazole (9) is the powerful seed germination inhibitor isolated from the African medicinal plant Triumfetta rhomboidea. Confirmation of its structure and its activity was obtained by synthesis through conversion of ethyl isoxazole-3-carboxylate into its acid chloride followed by reaction with MeMgBr 

The anthelmintically active plant Quisqualis indica contains its active principle quisqualic acid (13) (found as its potassium salt) located in the ) ernals. 

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