Selective inhibition of gastrointestinal beta-glucuronidase by polyvinylbenzyl D-glucaro(1,4)lactonate: attachment of D-glucaro(1,4)lactone to polyvinylbenzyl chloride.

D-Glucaro(1,4)lactone, a potent beta-glucuronidase inhibitor was attached via the carboxylic acid moiety to polyvinylbenzyl chloride (PVBC) using a bimolecular nucleophilic displacement reaction. First, the caesium salt of D-glucaro(1,4)lactone was prepared by titrating the carboxylic acid to neutrality with aqueous caesium bicarbonate. The polyvinylbenzyl D-glucaro(1,4)lactonate was obtained in maximum yields of between 50 and 60% when caesium D-glucaro(1,4)lactonate was incubated with PVBC in DMF at 50 degrees C for 7 d in the presence of a catalyst, caesium iodide.