Potent arylamide derivatives as dual-target antifungal agents: Design, synthesis, biological evaluation, and molecular docking studies

Fungal infections have become a serious medical problem due to the high infection rate and the frequent emergence of drug resistance. Ergosterol is an important structural component of the fungal cell membrane, its synthetases (squalene epoxidase (SE) and 14 alpha-demethylase (CYP51)) are considered as the key points to block the ergosterol synthesis. In this study, we designed a series of dual-target arylamides derivatives based on the analysis of active sites (SE, CYP51). Subsequently, these target compounds were synthesized, and their anti-fungal activity was evaluated. Most of compounds demonstrate the potent antifungal activity against multiple Candida spp. and A. fum. In particular, the antifungal activities of compounds 10b and 11c are not only superior to positive control drugs, but also have significant inhibitory effects on drug-resistant fungi (C.alb. Strain100, C.alb. Strain103). Therefore, their action mechanism was further studied. Cellular uptake and electron microscopy observation showed that target compounds were able to enter fungal cytoplasmic region through free diffusion, and destroyed cell membrane structure. At the same time, preliminary mechanisms have demonstrated that they can affect the synthesis of ergosterol by inhibiting the activity of dual targets. It is worth noting that they also can exhibit excellent antifungal activity and low toxic side effects in vivo. Their ADMET properties and binding models were established will be useful for further lead optimization.