for the following products
(3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl (2,5-dioxopyrrolidin-1-yl) carbonate | 1-({[(3R,3aS,6ar)-hexahydrofuro[2,3-b]furan-3-yloxy]carbonyl}oxy)pyrrolidine-2,5-dione and [(3R,3aS,6aR)-Hydroxyhexahydrofuro[2,3-b]furanyl Succinimidyl Carbonate