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D-Allose and its derivatives play important roles in the field of health care and food nutrition.Pure and well-detimed D-allose derivatives can facilitate the elucidation of their structure-activity relationship as an essential step for drug design.The Lattrell-Dax epimerization,refers to the triflate inversion using nitrite reagent,is known as valuable method for the synthesis of rare D-allose derivatives.Here,the influence of protecting group patterns on the transformation efficiency of D-glucose derivatives into synthetically useful D-alloses and D-allosamines via the Lattrell-Dax epimerization was studied.For C3 epimerization of D-glucose derivatives bearing O2-acyl group,an anomeric configuration-dependent acyl migration from O2 to O3 was found.In addition,a neighbouring group participation effect-mediated SN1 nucleophilic substitution of the D-glucosamine bearing C2 trichloroacetamido (TCA) group in the Lattrell-Dax epimerization was dependent upon anomeric configuration.Thus,the effect of anomeric configuration on the Lattrell-Dax epimerization of D-glucose suggests that β-D-glucosides with low steric hindrance at C2 should be better substrates for the synthesis of D-allose derivatives.Significantly,the efficient synthesis of the orthogonally protected D-allose 13 and D-allosamine 18 will serve well for further assembly of complex glycans.