In this study a series of six 3-hydroxynaphthalene-2-carboxanilides, substituted on the anilide ring by combinations of methoxy-methoxy, methoxy-fluoro and methoxy-chloro groups at different positions, was prepared by microwave-assisted synthesis and characterized. The compounds were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. The PET-inhibiting activity of the compounds was within a wide range, but rather moderate; the highest activity within the series of the compounds was determined for N-(3,5-dimehoxyphenyl)-3-hydroxynaphthalene-2-carboxamide (IC₅₀ = 24.5 µM). The compounds were found to inhibit PET in photosystem II.

Fucooligosaccharides are the main group into the human milk oligosaccharides. Due to their beneficial properties, a series of synthetic methods have been proposed to obtain them. In this way, the α-L-fucosidase from Thermotoga maritima has emerged as a powerful catalyst for fucooligosaccharides production. Nonetheless, the limited options in substrates for transfucosylation reactions have delayed its wider application. Thus, the present work aimed to compare the reactivity of fucose, pNP-fucose, and ethyl-fucose, as well as the molecular interactions among these fucosyl-donors and the enzyme through a DFT study and docking analysis. DFT analysis was carried out through B3LYP/6-311++G(2d,2p) level of theory, while docking analysis was made for hydrolysis and transfucosylation procedures by Autodock VINA. Both anomers of lactose and fucosyl-donors were full geometry optimized in aqueous phase, and HOMO-LUMO descriptors were calculated. Therefore, band gaps from -7.14571 to -4.24429 eV were found, where α/β-pNP-fucose and α-fucose were the three more reactive compounds. Concerning docking study, coupling energies between -6.4 to -5.5 kcal·mol^-1 were shown, being the α-pNP-fucose and α/β-ethyl-fucose the substrates with the lower enzyme affinity. In the case of lactose affinity to the complex β-fucose/enzyme, the disaccharide showed binding affinity energy of -5.7 and -5.8 kcal·mol^-1 for the α- and β-anomer, respectively. As a consequence, results suggest that the best fucosyl-donors for hydrolysis are those who maintain lower affinity with the enzyme active site, while there is not a significant difference among lactose anomers for their bonding to the enzyme-substrate complex.

Synthetic pesticides have been used for decades to manage pest control in crops, in order to avoid considerable damage and production losses due to pathogens, insects and other pest species. Nowadays, because of environmental and health issues, synthetic pesticides are being gradually replaced by botanical pesticides. Essential oils (EOs), plant’s secondary metabolites of low molecular weight and strong organoleptic properties, have been investigated as resources of potentially useful bioactive compounds, and it is known that they have an important role in the interactions between insects and plants. Carvacrol, a phenolic compound that is the main component in oregano essential oil, displays antimicrobial, antifungal, and insecticidal activities.

Considering these facts, the present investigation is focused on synthesis of new carvacrol derivatives possessing aliphatic carbon chains with different sizes as hydroxyl group substituents. All compounds were fully characterized by the usual analytical techniques, and their insecticide activity against the insect cell line Sf9 (Spodoptera frugiperda) was evaluated, to assess the potential application of these new derivatives as biopesticides.

Essential oils (EOs) have been studied owing to their properties, such as remarkable biological activities and health promoting benefits, including analgesic, anti-inflammatory, antibiotic, antioxidant and antimicrobial activities, as well as potential insecticides.

In spite of all their properties, EOs present low water solubility, poor bioavailability, volatility, reduced stability, and low resistance to environmental stresses like light, oxygen, and temperature which difficult their applications.

To mitigate these limitations, EOs can be incorporated into nanoencapsulation systems, this being a promising approach for the controlled release and preservation of their properties.

Considering these facts, in the present work, an eugenol oxirane, namely ethyl 4-(2-methoxy-4-(oxiran-2-ylmethyl)phenoxy)butanoate, with promising insecticidal activity, was submitted to encapsulation assays in lipid nanosystems, in order to boost its application as bioinsecticide.

N,N'-diphenyldithiomalonamide (dithiomalondianilide) smoothly reacts with various Michael acceptors to give either stable Michael adducts or products of their further heterocyclization. The structure of the products was confirmed by 2D NMR experiments and X-ray data. The mechanisms of the reactions are discussed.