Methods for Introducing Atoms Other than Oxygen into Sugar Rings

Abstract

Introduction In the last fifteen years some attention has been directed toward the production of modified sugars wherein the normal ring oxygen atom is replaced by another heteroatom. In some instances syntheses have been induced with the desire to create analogs which might possess interesting and even potentially useful properties and in some instances synthesis has reflected simply a basic interest in chemical structures and reaction chemistry. Our laboratory originally became interested in sugar analogs with sulfur replacing the ring oxygen because we anticipated that such analogs, but especially the analog of D-glucose, might possess new and useful biochemical effects. Our first sulfur analog was methyl 5-thio-α-D-xylopyranoside where the sulfur was locked into the ring by glycoside formation (1). Although we thought we were the first to introduce sulfur into a sugar ring and so commented at the time of writing, two other groups (2,3) reported 5-thio-D-xylose with the suggestion