Abstract: A new carbonate compound which is N,N'-di-succinimidyl carbonate, N,N'-diphthalimidyl carbonate or N,N'-bis(5-norbornene-2,3-dicarboxyimidyl) carbonate is produced by reacting an N-hydroxy compound of the formulaR-OHwherein R is succinimido, phthalimido or 5-norbornene-2,3-dicarboximido group, with a silylating agent, followed by reacting the resultant silylated product with phosgene, or alternatively by reacting said N-hydroxy compound with trichloromethyl chloroformate either in the molten state or in the presence of a non-polar organic solvent such as xylene.

Abstract: Novel sugar ureide and thioureide derivatives are provided by this invention, which exhibit certain antibacterial activity against a variety of gram-positive and gram-negative bacteria and useful in therapeutic treatment of bacterial infections. The compounds have the formula ##STR1## wherein R.sub.1 is a monovalent residue of aldose, aldonic acid and their 2-amino derivatives, R.sub.2 is an aralkyl, heterocyclic, sulfamoylaryl, R.sub.3 CONH or R.sub.4 NH-- where R.sub.3 is a heterocyclic and R.sub.4 is an aryl group and Y is oxygen or sulfur atom, which are prepared by reacting an isocyanate or isothiocyanate of the formula R.sub.1 NC=Y with an amino compound of the formula R.sub.2 NH.sub.2.