Conformationally constrained molecular frameworks of the 2,5-anhydro sugar diacid (9) and 2,5-anhydro sugar diamines (10, 11) were used to construct architecturally beautiful novel C-2 symmetric peptidomimetics 1-8. Although none of these compounds showed any significant HIV-I protease inhibitory activity, further refinements in design may lead to protease inhibitors based on these rigid carbohydrate-derived scaffolds. (C) 2000 Elsevier Science Ltd. All rights reserved.