A number of pro-moieties 8a-e designed for prodrug preparation have been synthesized (chart 2). The pro-moieties, containing a glucuronyl carbamate group linked to a spacer possessing a terminal carboxylic acid group, have been synthesized from isocyanates 6 and anomerically unprotected glucuronic acids 10 (chart 2). The requisite isocyanates had to be prepared using the Curtius rearrangement. Glucuronyl carbamates proved to be excellent ...