Synthesis of Symmetrical Dodeco‐6,7‐diuloses

Abstract

Dodeco‐6,7‐diuloses represent a rare class of sugars and can be considered as anomerically linked di‐hexoses with two hemiacetal functions in the middle. Herein, the synthesis of three symmetrical dodeco‐6,7‐diuloses (gluco‐gluco, galacto‐galacto, manno‐manno) is described. For their preparation four synthetic strategies were pursued, whose mutual key step, the connection of the anomeric centers, is particularly emphasized. Specifically, C–C bond forming methods are employed, such as a Grubbs metathesis, a stannyl glycal homocoupling reaction, a coupling of a sulfinyl glycal with a sugar lactone and a Ramberg–Bäcklund rearrangement. Since the ring closure via hemiacetal formation of the target compounds cannot be predicted, intensive NMR spectroscopic structure elucidation of the diuloses was performed.