Enantio-switching method

Enantio-switching Method for the Synthesis of Natural and Unnatural Products from Sugar Synthons... 

Enantio-switching method comprises c-glycosidation of atone epimenzation of its cobalt complex (3) and l 9. , . 01 alkyne>... 

We have further developed this enantio-switching method for the synthesis of natural products as outlined in Figure 3. In this method, enantio-switching... 

We have developed two methods for the synthesis of natural and unnatural products from D-glucose. Enantio-and diastereo-switching method established a new strategy for the synthesis of four possible stereomers for natural products synthesis, and this powerful method was successfully applied to the synthesis of unnatural protein phosphatase inhibitors. The second synthetic method involved the preparation of the urea-glycosidic linkages for the synthesis of glycopeptide mimics. 

Enantio-switching and Diastereo-switching Method for Natural Products... 

To a first approximation, the chiral discrimination should be independent of the nucleophile. The palladium-catalyzed desymmetrization protocol utilizing a heterocyclic nucleophile provides enantio- and diastereoselective entries to diverse carbo-nucleosides. As shown in Scheme 8E.9, introduction of purine bases rather than the hydroxymethyl synthon also affords high enantioselectivities [61]. A variety of natural and unnatural nucleosides can be flexibly prepared because the simple change of ligand chirality or, alternatively, switching the alkylation sequence leads to opposite enantiomers. The palladium-catalyzed approach sharply contrasts with the chiral-pool method, whose enantiodivergency is limited by the availability of the starting material. 

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