Crystal Habit Modification of Metronidazole by Supramolecular Gels with Complementary Functionality

A series of bis(urea) compounds with complementary functional groups similar to the pharmaceutical drug metronidazole and a structural isomer isometronidazole have been synthesized. The gelation properties of these compounds were studied in various solvent/solvent mixtures. The mechanical strength of the isomeric gelators was compared using rheology, and the morphologies of the xerogels were analyzed by scanning electron microscopy. These gels were used as media for metronidazole crystallization resulting in a marked habit modification of the metronidazole crystals in the drug-mimicking gels. However, crystallization in the nonmimetic isomeric gel resulted in morphologies similar to the solution state. These results indicate that the drug-mimetic gels interact with the surface of the drug crystal giving rise to new morphologies.

Automated summary

A series of bis(urea) compounds with complementary functional groups similar to the drug metronidazole and its structural isomer have been synthesized and studied for their gelation properties. It was found that drug-mimetic gels interact with the surface of the drug crystal, resulting in new crystal morphologies, while nonmimetic gels did not show this effect.