An Improved Synthesis of 6‐Deoxy‐Analogues of Cyclodextrins and Amylose. Further Interpretations of the Proton Magnetic Resonance Spectra of the Peracetates of Cyclodextrins and Amylose

A convenient procedure for the synthesis of 6‐deoxy‐analogues of cyclodextrins and amylose was developed. Selective bromination of primary hydroxyl groups in these compounds, and subsequent reductive debromination of the 2,3‐di‐O‐acetates lead to the corresponding 6‐deoxy‐derivatives after deacetylation. The conformation of the 2,3‐di‐O‐acetates of 6‐bromo‐6‐deoxy‐ and 6‐deoxy‐analogues of the dextrins and amylose was investigated by PMR‐spectroscopy. Furthermore, the chemical shift changes due to the modification at the C‐6 position was studied for the ring and acetyl‐methyl protons.