This study describes a virtual screening performed for two series of selenides (28 compounds), derived from N-phenylacetamides chlorides and 7-chloro-quinoline, to determine their potential for leishmanicidal activity against Leishmania amazonensis and Leishmania donovani. Seven compounds were predicted as potential leishmanicides; therefore, they were synthesized from elemental selenium, as a precursor for the production of NaHSe, and subsequent reactions with 4,7-dichloro-quinoline and N-phenylacetamides chlorides were performed. The compounds were characterized by infrared (IR), 1H and 13C nuclear magnetic resonance (NMR), and sent for in vitro cytotoxicity tests against L. amazonensis and were found to be active and selective, and two compounds presented half-maximal inhibitory concentrations (IC50) of 5.67 and 10.81 µg mL-1. They also presented good interaction energies in the docking study, suggesting that may exert their effects by inhibiting the N-myristoyltransferase and O-acetylserine sulfhydrylase enzymes in parasites.

Four new piperine derivatives, PC1-PC4, were synthesized, and their structures were fully characterized by infrared (IR) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopies. Quantum chemical calculations were performed using density functional theory (DFT) with the B3LYP-D3/6-31G(d,p) and 6-311+G(2d,p) basis sets. Electronic properties, such as the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) and some global chemical reactivity descriptors, were evaluated to study the reactivity and stability of the compounds. 1H and 13C NMR chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method and compared with experimental values. In addition, the compounds were evaluated in an antifungal study against Candida, Trichophyton and Microsporum strains, and only PC4 showed 70% inhibition in ten tested strains, with a minimum inhibitory concentration (MIC) ranging from 1.23-2.46 μmol mL-1 and a minimum fungicide concentration (MFC) ranging from 9.84-19.68 μmol mL-1, and presented a fungistatic effect.

A series of fifteen new piperine-derived diesters was synthesized through the substitution reaction between the salt of piperic acid, obtained through piperine basic hydrolysis, with the δ-chloro-esters, obtained through the cleavage of tetrahydrofuran (THF) with acyl chlorides in the presence of ZnCl2. The final compounds were obtained with yields ranging from 50 to 84% and were characterized by infrared (IR) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR). The new compounds were evaluated in silico in regard to their ADME (absorption, distribution, metabolism, and excretion) properties, and in vitro for their antimicrobial activity against bacteria strains (Staphylococcus aureus and Pseudomonas aeruginosas), yeast fungi (Candida albicans and C. tropicalis) and filamentous fungi (Aspergillus fumigatus, A. flavus and A. niger). The results from the in silico studies of Lipinski’s rule of five showed that most compounds present good pharmacological possibilities, and the results from in vitro antimicrobial activity showed that 8 of the 15 synthesized compounds displayed antimicrobial activity, inhibiting the growth of 40-80% of tested strains, with a minimum inhibitory concentration (MIC) interval ranging from 1024 to 256 µg mL−1.

Ten imides derived from safrole, 4a-4j, were synthesized and their structures were fully characterized by infrared (IR) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRMS) analysis. Among the ten imides studied, eight are new. The compounds were evaluated in an in silico study and showed strong to moderate antifungal activity against various strains of Candida and Cryptococcus. In particular, compounds 4b, 4c and 4h exhibited strong antifungal activity, with minimum inhibitory concentration (MICs) between 0.17-0.73 µmol mL-1. The compound 4j exhibited antifungal activity with MIC 1.28 µmol mL-1 for all strains tested. In silico studies of the parameters of Lipinski’s rule of five indicated that these compounds are potential new drug candidates. The predict oral bioavailability can be evaluated through these parameters. In addition, a computational study helped assigning the stereochemistry of compound 4j, where the synthesized mixture is composed by two stereoisomers, 4j(1) (SRR) and 4j(2) (RSS).

This work aims to investigate the energy-related characteristics of apple bagasse, orange bagasse and cashew-apple bagasse to identify their potential as bioenergy feedstocks. For this, a detailed characterization was performed, including proximate analysis, ultimate analysis, atomic molar ratio, heating values, chemical composition, bulk density, bioenergy density, fuel-value-index (FVI), fossil fuel equivalence and potential CO2 retention. Proximate composition revealed moisture, volatile matter, fixed carbon and ash contents in the range of 7.8-9.3%, 67.1-74.2%, 16.2-22.0% and 1.6-5.7%, respectively. Typical values for carbon (44.8-49.9 wt.%), hydrogen (5.5-6.6 wt.%) and oxygen (40.1-44.2 wt.%), with low sulfur (< 0.1 wt.%) and nitrogen (< 2.7 wt.%) contents were found. In regard to bulk density (237.7-554 kg m−3) and bioenergy density (3.93-10.1 GJ m−3), juice processing residues have substantial values when compared with well-known lignocellulosic residues. Recoverable energy potential from the juice processing residues varied from 15.24 to 17.03 MJ kg−1. From FVI analysis, apple bagasse is expected to be more suitable for thermochemical processing. Orange bagasse, on the other hand, has the highest equivalent in fossil fuel volume. Consequently, its use as solid fuel may lead to a decrease in CO2 emissions from reference fuels.

Piperine, previously extracted from black pepper (Piper nigrum L.), was used as a precursor for the synthesis of twelve new diester derivatives. The final products were obtained through the bimolecular nucleophilic substitution reaction (SN2) of the alkyl 2-chloroacetates and the salt of piperic acid, obtained from the basic hydrolysis of piperine. The compounds were synthesized with yields of 55-84% and characterized by infrared spectroscopy and 1H and 13C nuclear magnetic resonance. The evaluation of the compounds’ potential as new drug candidates was done through an in silico study of ADME properties (absorption, distribution, metabolization and excretion) and evaluation of antimicrobial activity against bacterial strains (Staphylococcus aureus and Pseudomonas aeruginosa), yeasts (Candida albicans and Candida tropicalis) and filamentous fungi (Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger). The in silico study showed that the compounds were good drug candidates and antimicrobial evaluation demonstrated that 9 of the 12 compounds exhibited a minimum inhibitory concentration (MIC) ranging 1024-256 μg mL-1.

New diesters derived from phthaloylglycine (7a-7i) were synthesized and their structures characterized by infrared, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The compounds were evaluated in an in silico study, which demonstrated positive features indicating a possible drug candidate. The diesters showed antifungal activity ranging from moderate to strong against strains of Candida. Compounds 7a, 7b, 7c, 7e and 7i had a moderate minimum inhibitory concentration (MIC) of 1024 µg mL−1 against all fungal strains, while 7h showed a very good MIC of 256 µg mL−1 against Candida albicans, Candida parapsilosis and Candida krusei and 64 µg mL−1 against Candida tropicalis. However, only 7h and 7i were able to inhibit bacterial growth of strains of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Escherichia coli with an MIC of 1024 µg mL−1.

Nine new compounds derived from selenoglycolic acid were synthesized, and their structures were fully characterized by elemental analysis, infrared (IR), 1H and 13C nuclear magnetic resonance (NMR). The compounds were evaluated in an in silico study and showed strong to moderate antibacterial activity against several strains of Staphylococcus aureus. In particular, three compounds exhibited excellent antibacterial activity, with minimum inhibitory concentrations (MICs) between 16 and 64 µg mL-1. Furthermore, two of the nine compounds showed antifungal activity, with MIC of 1024 and 512 µg mL-1. In silico studies of the parameters of Lipinski's rule of five indicate that these compounds have potential to be new drug candidates.

Abstract Fungal infections have become a concern for health professionals, and the emergence of resistant strains has been reported for all known classes of antifungal drugs. Among the fungi causing disease, we highlight those that belong to the genus Aspergillus. For these reasons, the search for new antifungals is important. This study examines the effects of a coumarin derivative, 4-acetatecoumarin (Cou-UMB16) both alone and together with antifungal drugs, and its mode of action against Aspergillus spp. Cou-UMB16 was tested to evaluate its effects on mycelia growth, and germination of Aspergillus spp. fungal conidia. We investigated its possible action on cell walls, on the cell membrane, and also the capacity of this coumarin derivative to enhance the activity of antifungal drugs. Our results suggest that Cou-UMB16 inhibits Aspergillus spp. virulence factors (mycelia growth and germination of conidia) and affects the structure of the fungal cell wall. When applying Cou-UMB16 in combination with azoles, both synergistic and additive effects were observed. This study concludes that Cou-UMB16 inhibits mycelial growth and spore germination, and that the activity is due to its action on the fungal cell wall, and that Cou-UMB16 could act as an antifungal modifier.

ABSTRACT Cissampelos sympodialis Eichler, Menispermaceae, a Brazilian medicinal plant and its alkaloid warifteine present immunomodulatory activity on asthma experimental model by reducing antigen-specific IgE levels, eosinophil infiltration and lung hyperactivity. Allergic rhinitis is a chronic inflammatory disorder of the nasal tissue that affect the quality of life and it is a risk factor for asthma exacerbation. This study evaluated the effect of inhaled warifteine in an allergic ovalbumin rhinitis model. Inhaled warifteine (2 mg/ml) treatment of ovalbumin-sensitized BALB/c mice significant decreased total and differential number of cells on the nasal cavity and decreased ovalbumin-specific IgE serum levels. Hematoxylin & eosin staining of histological preparations of ovalbumin nasal tissues showed changes such as congestion and a massive cell infiltration in the perivascular and subepithelial regions characterizing the nasal inflammatory process. However, inhaled warifteine or dexamethasone treatment decreased cell infiltration into the perivascular regions and it was observed an intact nasal tissue. Periodic acidic staining of nasal epithelium of ovalbumin animals demonstrated high amount of mucus production by goblet cells and inhaled warifteine or dexamethasone treatment modulated the mucus production. In addition, toluidine blue staining of the nasal epithelium of ovalbumin animals demonstrated an increase of mast cells on the tissue and inhaled warifteine or dexamethasone treatment decreased in average of 1.4 times the number of these cells on the nasal epithelium. Taken these data together we postulate that warifteine, an immunomodulatory alkaloid, can be a medicinal molecule prototype to ameliorate the allergic rhinitis conditions.

Abstract In a previous study, we reported the antispasmodic and gastroprotective effects of the Serjania caracasana (Jacq.) Willd., Sapindaceae, extract. In the present study, we evaluated the LD50, hemolytic and antispasmodic activities of its fractions and characterized its major constituents by isolation and GC–MS. The animals showed non-toxic symptoms with oral doses up to 2000 mg/kg, suggesting a safe oral administration. Furthermore, a low hemolytic activity was detected for the saponin fraction. Antispasmodic activity of the fractions was evaluated through carbachol-induced contractions in rat ileum. The hexane fraction was the most potent (IC50 68.4 ± 5.9 µg/ml) followed by the dichloromethane fraction (IC50 161.3.4 ± 40.7 µg/ml). Butanol fraction was the less effective (IC50 219.8 ± 60.3 µg/ml). The phytochemical study of the S. caracasana fractions afforded the isolation of friedelin, β-amyrin, allantoin and quercitrin. This is the first time that the presence of allantoin and quercitrin in the Serjania genus has been reported. Among the isolated compounds and those characterized by GC–MS, β-amyrin and β-sitosterol were present in the most active fractions, hexane and dichloromethane, and they may be related to its antispasmodic activity. In addition, spathulenol was only found in the hexane fraction and its presence might justify the highest antispasmodic activity observed for this fraction.

A series of ten new compounds have been synthetized in satisfactory yields (85-95%) through the treatment of isopropyl mesoionic 1,3-thiazolium-5-thiolate with 2-chloro-N-arylacetamides and characterized by elemental analysis, infrared (IR), 1H and 13C nuclear magnetic resonance (NMR) spectroscopies. The newly synthesized compounds were evaluated as new drug candidates in in silico study and for their antifungal activity against several strains of Candida albicans. In silico study indicates that no compound has potential to be a new drug while four compounds showed medium to strong activity with minimum inhibitory concentration (MIC) range of 256-1024 µg mL-1.

Uma série de 21 derivados, 1,3,4-oxadiazolinas, foi sintetizada pela ciclização de N-acilhidrazonas com anidrido acético e avaliada in vitro quanto à sua atividade antifúngica contra seis espécies de Candida: Candida albicans (ATCC 90028 e LM V-42), Candida krusei (ATCC 6258 e LM 12 C) e Candida tropicalis (ATCC 13803 e LM 14). As espécies de Candida foram consideradas sensíveis a uma série dos compostos, os quais inibiram o crescimento de 50 a 90%, com um intervalo de concentração inibitória mínima (MIC) de 64 a 512 µg mL-1. As estruturas dos compostos foram totalmente confirmadas e caracterizadas pelas técnicas de infravermelho com transformada de Fourier (FTIR), ressonância magnética nuclear (NMR) de ¹H e 13C, e espectrometria de massa (MS).

A series of 21 1,3,4-oxadiazoline derivatives was synthesized by cyclization of N-acylhydrazones with acetic anhydride and evaluated for their in vitro antifungal activity against six Candida strains: Candida albicans (ATCC 90028 and LM V-42), C. krusei (ATCC 6258 and LM 12 C) and C. tropicalis (ATCC 13803 and LM 14). The Candida strains were found to be sensitive to some of the compounds, which inhibited the growth by 50-90%, with minimum inhibitory concentration (MIC) in the range of 64-512 µg mL-1. The compounds' structures were fully confirmed and characterized by Fourier transform infrared spectroscopy (FTIR), ¹H and 13C nuclear magnetic resonance (NMR) and mass spectrometry (MS).

A investigação fitoquímica das raízes de Krameria tomentosa A. St. -Hil. levou ao isolamento de cinco neolignanas, duas delas com estruturas inéditas [1,1'-(E)-propenil4-metóxi-3,4'-oxineolignana (ottomentosa) e ácido 2-(2'-hidróxi-4',6'-dimetoxifenil) benzofurano-5-carboxílico (sobralina)], além de três compostos conhecidos [eupomatenoide 6, di-hidrocarinatidina e 2-(2',4'-di-hidroxifenil)-5-(E)-propenilbenzofurano]. A caracterização estrutural dos compostos isolados foi estabelecida com base na espectroscopia no infravermelho, espectrometria de massas, ressonância magnética nuclear uni e bidimensional, além de comparação com dados espectrais descritos na literatura.

A phytochemical investigation of the roots of Krameria tomentosa A. St. -Hil. led to the isolation of five neolignans, two of them with novel structures [1,1'-(E)-propenyl-4-methoxy3,4'-oxyneolignan (ottomentosa) and 2-(2'-hydroxy-4',6'-dimethoxyphenyl)benzofuran5-carboxylic acid (sobraline)] and three known compounds [eupomatenoid 6, dihydrocarinatidin and 2-(2',4'-dihydroxyphenyl)-5-(E)-propenylbenzofuran]. The structural characterization of the compounds isolated was established based on infrared spectroscopy, mass spectrometry, one-and two-dimensional nuclear magnetic resonance, along with comparison with spectral data described in the literature.

The cardiovascular effects elicited by the ethanolic extract obtained from the roots of Erythroxylum pungens O.E. Schulz, Erythroxylaceae (EEEP) and the vasorelaxant effect induced by its main tropane alkaloid (pungencine) were investigated. In normotensive rats, administration of EEEP (1, 10, 30 and 60 mg/kg i.v., randomly) produced dose-dependent hypotension (-2±1, -7±0.5 -17.6±1, -24±1 Δ mmHg, n=5) followed by tachycardia (3±0.5, 7±2, 7.1±1, 10±5 Δ bpm, n=5). In intact phenylephrine (Phe, 10 µM)-pre-contracted rings, EEEP (0.01-500 µg/mL) induced concentration-dependent vasorelaxation (EC50 13.7±5.5 µg/mL, Maximal Response= 92±2.6%), and this effect was unchanged after the removal of the vascular endothelium (EC50 27.2±4.7 µg/ml, Maximal Response= 88.3±3.3 %). In KCl (80 mM)-pre-contracted-endothelium-denuded rings, EEEP elicited concentration-dependent relaxation (EC50= 128.2±11.2 µg/mL, Maximal Response 76.8±3.4%). Vasorelaxation has also been achieved with tonic contractions evoked by the L-type Ca2+ channel agonist Bay K 8644 (EC50 80.2±9.1 µg/mL, Maximal Response 86.3±8.3%). In addition, in a depolarizing medium, EEEP inhibited CaCl2 (30-500 µg/mL) induced contractions and caused a concentration-dependent rightward shift of the relaxation curves. Lastly, the tropane alkaloid pungencine caused vasorelaxation in mesenteric arteries resembling to the EEEP responses. These results suggests that EEEP induces hypotension and vasorelaxation, at least in part, due to the reduction in [Ca2+]i in vascular smooth muscle cells.