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Three simple bisamide derivatives (<b>G1</b>, <b>G2</b> and <b>G3</b>) with different structural modifications were synthesized with easy synthetic procedures in order to test their gel behaviour. The outcomes showed that hydrogen bonding was essential in gel formation; for this reason, only <b>G1</b> provided satisfactory gels. The presence of methoxy groups in <b>G2</b> and the alkyl chains in <b>G3</b> hindered the hydrogen bonding between N-H and C=O that occurred <b>G1</b>. In addition, <b>G1</b> provided thermally and mechanical stable gels, as confirmed with T_sol and rheology experiments. The gels of <b>G1</b> were also responsive under pH stimuli and were employed as a vehicle for drug crystallization, causing a change in polymorphism in the presence of flufenamic acid and therefore providing the most thermodynamically stable form III compared with metastable form IV obtained from solution crystallization.