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Eremophilanes from Senecio mairetianus and some reaction products
Ana-L Pérez-Castorena1, Amira Arciniegas, S Laura Guzman
1Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacan 04510, D.F., México. alperezc@servidor.unam.mx
Abstract:
Eight new eremophilanolides (1, 2, 4-7, 9, and 10), a new eremophilane (13), and several known compounds were isolated from the roots and aerial parts of Senecio mairetianus. The chemical structures were proposed taking into consideration spectroscopic analyses and chemical transformations. X-ray diffraction analysis of 2, 4, and 9 confirmed their structures. The stereochemistry of 1,10-epoxy-8alpha-methoxyermophilanolide (3) was determined. Compounds 4-7, 9, and 10 are possible artifacts obtained by preparation of the alkaloidal extract.
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