Expeditious Synthesis of New 3,4,6‐Trihydroxythiepanes from d‐(‐)‐Quinic Acid

Abstract

We report herein that the new seven‐membered‐ring thiosugars (thiepanes) have been synthesized from d‐(‐)‐quinic acid. The key feature of the synthesis involves the thiocyclization of protected hexane‐1,2,3,5,6‐pentanol derivatives. The subsequent step of acidic removal of protecting groups is critical in the reaction conditions to obtain the required 3,4,6‐trihydroxythiepanes. During the course of studies, the unexpected trihydroxythiopyrans are formed because of the ring contractions of their corresponding trihydroxythiepanes under various conditions.

Keywords:

• quinic acid
• thiepane
• thiosugar

Acknowledgement

This work was financially supported by the National Science Council (NSC94‐2113‐M‐032‐006) and Tamkang University.