Alzheimer’s disease (AD) is a neurodegenerative disorder mostly influencing the elderly, and causes death due to dementia. The main pathogenic feature connected with the progression of this multifactorial disease is the weakening of the cholinergic system in the brain. Cholinesterase (ChE) inhibitors are recognized as one of the choices in the treatment of AD. The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were approved as a therapeutic strategy to reduce the symptoms of AD and prevent its progression. The capacity of BChE is not completely known yet; rather, it is accepted to assume a part in a few disorders such as AD. Thus, BChE inhibitors may have a greater role for the treatment of AD in the future. In the present study, 2-(9-acridinylamino)-2-oxoethyl piperazine/piperidine/morpholinecarbodithioate derivatives were synthesized in order to investigate anticholinesterase activity. Eight derivatives demonstrated a specific and promising action against BChE. Furthermore, compound 4n showed inhibitory activity against both enzymes. It was found that the active compounds were well tolerated in the cytotoxicity test. Possible interactions between the lead compound, 4n, and the BChE enzyme were determined through a docking study. The findings obtained within this paper will contribute to the development of new and effective synthetic anti-Alzheimer compounds, and will ideally encourage future screening against AD.

Owing to the growing need for antifungal agents, we synthesized a new series 2-((5-(4-(5-substituted-1H-benzimidazol-2-yl)phenyl)-4-substituted-4H-1,2,4-triazol-3-yl)thio)-1-(substitutedphenyl)ethan-1-one derivatives, which were tested against Candida species. The synthesized compounds were characterized and elucidated by FT-IR, ¹H-NMR, ¹³C-NMR and HR-MS spectroscopies. The synthesized compounds were screened in vitro anticandidal activity against Candida species by broth microdiluation methods. In vitro cytotoxic effects of the final compounds were determined by MTT assay. Microbiological studies revealed that compounds 5m, 5o, 5r, 5t, 5y, 5ab, and 5ad possess a good antifungal profile. Compounds 5w was the most active derivative and showed comparable antifungal activity to those of reference drugs ketoconazole and fluconazole. Cytotoxicity evaluation of compounds 5m, 5o, 5r, 5w, 5y, 5ab and 5ad showed that compounds 5w and 5ad were the least cytotoxic agents. Effects of these two compounds against ergosterol biosynthesis were observed by LC-MS-MS method, which is based on quantification of ergosterol level in C. albicans. Compounds 5w and 5d inhibited ergosterol biosynthesis concentration dependently. A fluorescence microscopy study was performed to visualize effect of compound 5w against C. albicans at cellular level. It was determined that compound 5w has a membrane damaging effect, which may be related with inhibition of biosynthesis of ergosterol.

A new series of N-pyridyl-hydrazone derivatives was synthesized by using a simple and efficient method. The final compounds obtained were screened for their inhibitory potency against monoamine oxidase (MAO) A and B. The newly synthesized compounds 2a–2n specifically inhibited monoamine oxidases, displaying notably low IC₅₀ values. Compounds 2i and 2j, with a CF₃ and OH group on the 4-position of the phenyl ring, respectively, showed considerable MAO-A and MAO-B inhibitory activities. Compounds 2k, 2l and 2n, with N-methylpyrrole, furan and pyridine moieties instead of the phenyl ring, were the most powerful and specific inhibitors of MAO-A, with IC₅₀ values of 6.12 μM, 10.64 μM and 9.52 μM, respectively. Moreover, these active compounds were found to be non-cytotoxic to NIH/3T3 cells. This study supports future studies aimed at designing MAO inhibitors to obtain more viable medications for neurodegenerative disorders, such as Parkinson’s disease.

Lanosterol 14α-demethylase (CYP51) is an essential enzyme in the fungal life cycle and also an important target for antifungal drug development. Selective inhibition of the enzyme would cause depletion of ergosterol and accumulation of lanosterol and result in the growth inhibition of the fungal cell [1].