| Abstract
| - A neighboring equatorial ester group plays a highly important role in the Lattrell−Dax (nitrite-mediated)carbohydrate epimerization reaction, inducing the formation of inversion compounds in good yields. Onthe basis of this effect, efficient synthetic routes to β-d-mannosides and β-d-talosides, from thecorresponding β-d-galactosides and β-d-glucosides, have been designed. The present routes are basedon multiple regioselective acylation via the respective stannylene intermediates, followed by inversionsto the corresponding manno- and talopyranoside structures by nitrite or acetate substitution. It was foundthat the ester group was able to induce the inversion of its two neighboring groups in high yields followingeither a double parallel or a double serial inversion process. By combination of direct inversion, andneighboring- as well as remote-group participation, several β-d-mannoside and β-d-taloside derivativeswere very conveniently obtained in good yields.
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