Synthesis of Cyclic Imides (Methylphtalimides, Carboxylic Acid Phtalimides and Itaconimides) and Evaluation of their Antifungal Potential.

BACKGROUND

This paper describes the synthesis of three different subfamilies of cyclic imides: methylphtalimides, carboxyl acid phtalimides and itaconimides.

METHODS

Fifteen compounds (five of each sub-family) were obtained by the reaction of appropriated anhydrides and different aromatic amines, using the manual Topliss method. Their structures were confirmed by spectral data (IR and NMR). The antifungal activity of the synthesized compounds was investigated by broth microdilution to determine the minimal inhibitory concentration (MIC). The ability to inhibit the biofilm formation or destroy mature Candida albicans biofilm was also evaluated for the most active substances.

RESULTS

The results indicated that only the itaconimides 11-15 exhibited potent and promising antifungal properties, with MIC100 between 1 and 64 μg mL-1, being several times more potent than the reference drug, Fluconazole. Compounds 11-15 inhibited between 64% and 95% of biofilm formation, and destroyed between 78% and 99% of mature biofilm at a concentration of 64 μg mL-1. ADME (absorption, distribution, metabolism and excretion) in silico evaluations were carried out to predict whether the molecules under study are good drug candidates.

CONCLUSIONS

Itaconimides appear to be promising and relevant as tools for the future development of new and effective medicinal agents to treat fungal diseases.