Alzheimer's disease is a complex neurodegenerative disorder of the central nervous system, characterized by amyloid-β deposits, τ-protein aggregation, oxidative stress and reduced levels of acetylcholine in the brain. One pharmacological approach is to restore acetylcholine level by inhibiting acetylcholinesterase (AChE) with reversible inhibitors, such as galanthamine, thus helping to improve the cognitive symptoms of the disease. In order to design new galanthamine derivatives and search for novel, potential inhibitors with improved interactions, as well as a suitable pharmacokinetic profile and low toxicity, several molecular modeling techniques were applied. These techniques included the investigation of AChE-drug complexes (1QT1 and 1ACJ Protein Data Bank codes), ligand-binding sites calculation within the active site of the enzyme, pharmacophore perception of galanthamine derivatives, virtual screening, toxicophorical analysis and estimation of pharmacokinetics properties. A total of four galanthamine derivatives having a N-alkyl-phenyl chain were designed, since the tertiary amine substituents could reach the peripheral anionic site that is not occupied by galanthamine. In addition, 12 drug-like compounds from the Ilibdiverse database were selected by virtual screening as novel, hypothetical AChE inhibitors. The toxicophorical analysis revealed that only four proposed inhibitors have chemical groups able to develop mutagenicity and chromosome damage. The remaining compounds showed only mild or none toxicophorical alerts. At least three screened compounds presented theoric parameters consistent with good oral bioavailability. The designed molecules have the potential to become new lead compounds that might guide the design of drugs with optimized pharmacodynamic and pharmacokinetic properties in order to improve the treatment of Alzheimer's disease by creating new pharmacotherapeutic options.

Triazole, which can exist in two isomeric forms: 1,2,3- and 1,2,4-triazole, is considered to be a privileged scaffold with recognized biological and pharmaceutical potential. Furthermore, due to their physicochemical properties, the applications of triazoles have been explored in fields ranging from medicinal chemistry to materials science. Triazoles have not only drawn the attention of the scientific community for all the aforementioned properties but also due to their ability to be incorporated into other bioactive and functional molecules. The connection between two pharmacophores makes it possible to potentiate specific biological activities or add different properties. Interest in the compatibility of the triazole nucleus with peptide structures is highlighted in the development of new therapeutic targets. In epigenetics, triazole is linked to various compounds that are used in the creation of new drugs that could potentially inhibit histone-modifying enzymes. Other new and potentially more effective materials that can take advantage of a triazole moiety include light-emitting diodes and solar cells, among others. Hence, we propose a novel approach to the promising applications of triazolic ring, a compound that has been gaining prominence in organic chemistry due to its applicability to many different fields.

Background: Fusarium solani f. sp. piperis is a phytopathogen that causes one of the most destructive diseases in black pepper crops, resulting in significant economic and crop production losses. Consequently, the control of this fungal disease is a matter of current and relevant interest in agriculture. Objective: The objective was to synthesize eugenol derivatives with antifungal activity. Methods: In this study, using bimolecular nucleophilic substitution and click chemistry approaches, four new and three known eugenol derivatives were obtained. The eugenol derivatives were characterized and their antifungal and cytotoxic effects were evaluated. Results: Eugenol derivative 4 (2-(4-allyl-2-methoxyphenoxy)-3-chloronaphthalene-1,4-dione) was the most active against F. solani f. sp. piperis and showed acceptable cytotoxicity. Compound 4 was two-fold more effective than tebuconazole in an antifungal assay and presented similar cytotoxicity in macrophages. The in silico study of β-glucosidase suggests a potential interaction of 4 with amino acid residues by a cation-π interaction with residue Arg177 followed by a hydrogen bond with Glu596, indicating an important role in the interactions with 4, justifying the antifungal action of this compound. In addition, the cytotoxicity after metabolism was evaluated as a mimic assay with the S9 fraction in HepG2 cells. Compound 4 demonstrated maintenance of cytotoxicity, showing IC50 values of 11.18 ± 0.5 and 9.04 ± 0.2 μg mL-1 without and with the S9 fraction, respectively. In contrast, eugenol (257.9 ± 0.4 and 133.5 ± 0.8 μg mL-1), tebuconazole (34.94 ± 0.2 and 26.76 ± 0.17 μg mL-1) and especially carbendazim (251.0 ± 0.30 and 34.7 ± 0.10 μg mL-1) showed greater cytotoxicity after hepatic biotransformation. Conclusion: The results suggest that 4 is a potential candidate for use in the design of new and effective compounds that could control this pathogen.

Background: Effective cancer treatment is a major public health challenge. The limitations of current therapies and their adverse effects reduce the efficacy of treatment, leading to significant mortality rates worldwide. In this setting, natural product chemistry occupies a prominent role in the search for new treatment alternatives, by contributing a spectrum of chemical structures that may potentially yield new bioactive compounds. The compound [6]-gingerol (1) is the main active substance in ginger (Zingiber officinale) and several studies have shown it to have beneficial effects, including antitumor activity. Objective: This work aims to obtain new gingerol derivatives with cytotoxic activity. Method: We isolated [6]-gingerol and derivatizations using click chemistry, obtaining eight new compounds. All chemical structures were determined by means of IR, NMR and HRMS data, and cytotoxicity was evaluated in the HCT 116 (colon carcinoma) and MCF-7 (breast carcinoma) cell lines at concentrations of 5 μmol L^-1 and 50 μmol L^-1. Results: At 50 μmol L^-1, we achieved more than 70% inhibition of cell growth with compounds 2e, 2g against HCT 116, and 2b, 2d, 2e, 2f and 2g against MCF-7. Conclusion: The obtained compounds showed only moderate cytotoxic activity. However, the products with substituents occupying the meta position in relation to the triazole ring showed increased cytotoxic properties. The brominated compound (2g) showed the strongest activity, inhibiting cell proliferation by 87%.