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Synthesis of cardenolides

Because a substantial excess of the halide is used in the Koenigs-Knorr synthesis of cardenolides, it is usually difficult, if not impossible, to secure the acylated intermediate in crystalline form. Hence, Reichstein nd coworkers18 introduced a procedure whereby the whole of the products arising from the coupling reaction are saponified, employing a solution of potassium hydrogen carbonate in aqueous methanol. This modified transesterification procedure renders all extraneous carbohydrate materials water-soluble the methanol is removed by evaporation, leaving an aqueous solution from which the (deacylated) cardenolide may be obtained by... [Pg.280]

Luta, M., Hensel, A. and Kreis, W. (1998) Synthesis of cardenolide glycosides and putative biosynthesis precursors of cardenolide glycosides. Steroids, 63,44-9. [Pg.357]

After completion of the total synthesis of cardenolides, the main interest in this field has been in structural modifications, undoubtedly as a result of the group s... [Pg.430]

Cardenolides. A new, efficient synthesis of cardenolides is shown in the formulation. ... [Pg.403]

Overman, L.E. and Rucker, P.V. (1998) Enantioselective synthesis of cardenolide precursors using an intramolecular Heck reaction. Tetrahedron Lett., 39, 4643-6. [Pg.564]

Efficient Synthesis of Cardenolides. A general and efficient method has been described for the synthesis of cardenolides, consisting of (1) a-methylsulfenylation of pregnen-20-one, (2) Refor-matsky reaction, and (3) butenolide formation by alumina chromatography of the epoxy ester obtained from the S-methylated Reformatsky product (eq 4). ... [Pg.398]

New Strategy Based on Sequential Michael/Aldol Reactions for the Asymmetric Synthesis of Cardenolides... [Pg.237]

Application to the Synthesis of Cardenolides with Natural and Unnatural Configuration... [Pg.261]

See other pages where Synthesis of cardenolides is mentioned: [Pg.17]    [Pg.191]    [Pg.275]    [Pg.279]    [Pg.279]    [Pg.297]    [Pg.301]    [Pg.304]    [Pg.125]    [Pg.125]    [Pg.237]    [Pg.239]    [Pg.241]    [Pg.243]    [Pg.245]    [Pg.253]    [Pg.255]    [Pg.259]    [Pg.261]    [Pg.265]    [Pg.265]    [Pg.267]   
See also in sourсe #XX -- [ Pg.21 ]

See also in sourсe #XX -- [ Pg.21 ]

See also in sourсe #XX -- [ Pg.21 ]

See also in sourсe #XX -- [ Pg.21 , Pg.273 , Pg.321 ]



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Cardenolide

Cardenolide synthesis

Cardenolides

Of cardenolide

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