Abstract The β-carboline-1,3,5-triazine hydrochlorides 8-13 were evaluated in vitro against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The analysed compounds were selective to BuChE, with IC50 values in the range from 1.0-18.8 µM being obtained. The N-{2-[(4,6-dihydrazinyl-1,3,5-triazin-2-yl)amino]ethyl}-1-phenyl-β-carboline-3-carboxamide (12) was the most potent compound and kinetic studies indicate that it acts as a competitive inhibitor of BuChE. Molecular docking studies show that 12 strongly interacts with the residues of His438 (residue of the catalytic triad) and Trp82 (residue of catalytic anionic site), confirming that this compound competes with the same binding site of the butyrylthiocholine.

Sesquiterpene lactones are an important class of secondary metabolites frequently isolated from Vernonanthura genus that present a variety of biological properties, including antiproliferative activity. Due to the limitation of pharmacological studies on Vernonanthura nudiflora, the aim of this work was to investigate their antioxidant potential and antiproliferative activity against human tumor cells, as well as to isolate and identify the chemical constituents present in their aerial parts. The phytochemical investigation resulted in the isolation of the sesquiterpene lactones piptocarphins A, B, D, and a new hirsutinolide derivative, 8α-tigloyloxy-10α-hydroxy-hirsutinolide, besides triterpenes, glycosylated steroids, flavonoids, and one chlorogenic acid derivative. Also, other sesquiterpene lactones were identified by ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UHPLC-HRMS/MS) from dichloromethane fraction. This fraction showed activity against the tumor cells tested, mainly against leukemia, glioma, ovarian and kidney, with growth inhibitory activity (GI50) less than 0.80 µg mL-1. Piptocarphins A and B, in mixture, showed strong activity against all human cancer cell lines tested, with GI50 values ≤ 0.15 µg mL-1. Piptocarphin D was selective for glioma and resistant ovarian cell lines. The new hirsutinolide derivative showed potent activity against breast (GI50= 0.96 µg mL-1) and resistant ovarian (GI50 = 3.60 µg mL-1) cell lines.

In this work a series of 28 novel pyrazolo[3,4-d]pyridazin-7-ones were synthesized and tested against Leishmania amazonensis (strain WHOM/BR/75/JOSEFA) in promastigote and axenic amastigote forms. Five compounds were active against both cellular forms with IC50 (inhibitory concentration growth of 50%) values of 20.2, 11.7, 16.2, 29.5 and 40.3 µM for promastigote and 17.4, 25.2, 3.84, 21.8 and 22.7 µM for axenic amastigote. All compounds were studied by the Lipinski rule, cytotoxicity both in silico and in vitro to fibroblast line (L929) and macrophages (J774A1), and the most active compound showed a selectivity index of 59.9.

Quantitative interaction of twelve β-carboline derivatives with calf thymus deoxyribonucleic acid (ctDNA) using spectroscopic techniques was evaluated. The values of the binding constants (Kb) obtained for the complexes formed with the ctDNA ranged from 3.30 × 102 to 1.82 × 106 mol L−1, being the β-carbolines with the N,N-dimethylaminophenyl group at position 1 the ones which presented the highest Kb values. The binding mode between the β-carbolines evaluated and ctDNA was proposed from the KI assay, competition with ethidium bromide, and DNA thermal denaturation profile (Tm), where it was possible to infer that the evaluated alkaloids interact with ctDNA preferably via intercalation. Additionally, the correlation of Kb values obtained with the IC50 of seven human cancer cell lines was carried out. From this study, it was possible to observe a linear relation among most of the evaluated derivatives, obtaining r2 values from 0.5360 to 0.9600. In addition, in silico molecular docking was performed to corroborate the experimental results.

Chemical investigation of Guettarda viburnoides (leaves) led to the isolation of ursolic acid, uncaric acid, secoxyloganin, and grandifloroside, along with a mixture of quercetin-3-O-β-D-galactopyranoside and quercetin-3-O-β-D-glucopyranoside, and of β-sitosterol and stigmasterol. The structures of the isolated compounds were elucidated on the basis of their NMR data. The crude extract, ethyl acetate fraction, aqueous-methanol fraction, and grandifloroside showed significant DPPH free-radical scavenging activities with IC50 ranging from 18.92 to 26.47 µg mL-1. The topical administration of the crude extract and fractions markedly reduced the croton oil-induced mice ear edema in 67.0%-99.0%. Inhibition of tissue MPO activity was also observed, which demonstrated an anti-inflammatory effect of the G. viburnoides species.

This study aimed to evaluate the anti-inflammatory and repair effects of the ethanolic extract and ointment of Equisetum pyramidale on the skin lesions of rats induced to diabetes. After the induction of diabetes with alloxan, a surgical procedure was performed on the back of each rat. Then, they were separated into treatment groups: G1 ethanol extract of E. pyramidale; G2-ointment (extract of E. pyramidale 80g + 20g of vaseline:lanolin 1:1); G3 control (vehicle vaseline:lanolin 1:1); and G4-no treatment during 3, 7 and 14 days. The samples were embedded in paraffin and stained with hematoxylin-eosin for histological analysis. The findings showed that the use of ethanolic extract as well as the ointment decreased the inflammatory cells at the site of inflammation, resulting a faster healing, with less crusting and lower amount of secretion in comparison to the control group. Therapy with topical herbal was an effective method in the inflammatory process of tissue repair, contributing to a faster and more organized tissue re-epithelialization.

A phytochemical investigation of Maclura tinctoria fruits yielded five flavonoids, including one prenylated flavonol (licoflavonol) and four prenylated isoflavones (wighteone, derrone, alpinum isoflavone, and 6-(2,2-dimethyl-2H-chromen-6-yl)-2-(1-hydroxy-1-methylethyl)-2,3-dihydro-5H-furo[3,2-g]chromen-5-one). The structures of the isolates were established by analyzing their spectroscopic data. Compound 6-(2,2-dimethyl-2H-chromen-6-yl)-2-(1-hydroxy-1-methylethyl)-2,3-dihydro-5H-furo[3,2-g]chromen-5-one is new and the other isolates are described for the first time in this species.

Endophytic microorganisms, defined as fungi or bacteria that colonize the interior of plants without causing any immediate negative effects or damages, have reciprocal relationships with host plants. In some cases their presence is beneficial to the host due to the synthesis of bioactive compounds, among which several alcohols, esters, ketones and others that may react with other compounds and may be lethal to pathogenic microorganisms. Diaporthe helianthi (Phomopsis helianthi in its anamorphic phase) is available worldwide, especially in Europe, Asia and America. Isolated in Europe as an agent of the sunflower stem cancer, it has also been endophytically isolated from tropical and temperate plants. A D. helianthi strain isolated from Luehea divaricata has been employed in current research. An investigation of the secondary metabolite from D. helianthi by CC and NMR of ¹H and 13C yielded the separation of 10 fractions and the identification of the phenolic compound 2(-4 hydroxyphenyl)-ethanol (Tyrosol). Its antimicrobial reaction was tested and the ensuing antagonistic effects on the human pathogenic bacteria Enterococcus hirae, Escherichia coli, Micrococcus luteus, Salmonella typhi, Staphylococcus aureus, phytopathogenic Xanthomonas asc. phaseoli and phytopathogenic fungi were demonstrated. Results show that bioactive compounds and Tyrosol produced by D. helianthi have a biotechnological potential.

Objetivou-se com este estudo avaliar o potencial alelopático de extratos metanólicos de folhas, flores e raízes de capuchinha (Tropaeolum majus L.) sobre a germinação de sementes e o crescimento inicial de plântulas de picão-preto. O extrato metanólico com melhor potencial de inibição foi submetido a particionamento, resultando nas frações hexânica, clorofórmica, acetato de etila e hidrometanólica e posterior caracterização pelo espectro de absorção na região do infravermelho (IV). O efeito alelopático foi avaliado sobre as sementes de picão-preto, as quais foram distribuídas sobre papel germitest umedecido com 2mL dos extratos e mantidas em germinador do tipo B.O.D. regulado a temperatura de 25°C e luz branca constante, sendo que as sementes imersas diretamente em água constituíram o tratamento controle. A avaliação da qualidade da semente foi realizada pelos testes de germinação e vigor (primeira contagem e comprimento de raiz primária e de hipocótilo das plântulas), em delineamento inteiramente ao acaso. O potencial alelopático das folhas de capuchinha foi maior em relação às demais partes da planta sobre a germinação das sementes, comprimento de hipocótilo e de raiz das plântulas de picão-preto. Estes efeitos podem estar associados à presença de grupos químicos polares, pois à medida que se aumentou a polaridade dos solventes detectou-se maior efeito inibitório sobre a germinação e o crescimento inicial de plântulas de picão-preto.

This research aimed to evaluate the metanolic extracts allelopathic potential from leaves, flowers and roots of capuchinha (Tropaeolum majus L.) on picão-preto seeds germination and initial seedling growth. The best inhibitor metanolic extract was fractioned, in hexanic, cloroformic, etil acetate and hidrometanolic fractions and it was characterized through absorption spectrum using mid-infrared. To evaluate the allelopathic effect of metanolic extracts and the fractions aftereffect; it was used picão-preto seeds distributed on 2ml extracts moistured paper maintained in B.O.D. germinator at 25°C and white constant light. Seeds sowed directly in water moistured germitest paper constituted the control. The allelopathic potential extracts were evaluated through the first count, final germination percentage, seedlings primary root and hypocotyl length (cm). The experiment was carried out DIC with three replications of 25 seeds. The capuchinha leaves showed allelopathic potential on picão-preto seeds germination, hypocotyl and seedlings primary root length. It was suggested that such effects are associated to the presence of polar chemical groups because the increase in the solvents polarity detected the major picão-preto germination and seedlings growth inhibition effect.

O extrato etanólico das folhas de Paullinia elegans Cambess., Sapindaceae, e as frações n-hexano, clorofórmio, acetato de etila e hidroetanólica, obtidas de seu fracionamento, foram avaliadas quanto às suas atividades anti-edematogênica e sequestradora de radicais livres. O extrato etanólico e a fração hexano produziram inibição significativa (74,4 e 76,0%, respectivamente) do edema da orelha induzido pelo óleo de cróton em ratos, em doses de 5 mg/orelha. As frações acetato de etila e hidroetanólica mostraram atividade sequestradora de radicais livres no ensaio de DPPH, com IC50 de 36,7 e de 30,1 µg/mL, respectivamente. O fracionamento dos extratos pelo uso de métodos cromatográficos resultou no isolamento do epifriedelanol, ácido 3-O-acetil oleanólico, mistura do stigmasterol 3-β-O-glucopiranosídeo e sitosterol 3-β-O-glucopiranosídeo, canferol, canferol 3,7-O-α-diramnopiranosídeo, canferol 3-O-α-ramnopiranosídeo e 2-O-metil-chiro-inositol. Os compostos foram identificados com base na comparação de seus dados espectroscópicos de RMN com os da literatura.

Ethanol extract of the leaves of Paullinia elegans Cambess., Sapindaceae, and its hexane, chloroform, ethyl acetate, and hydroethanol fractions were evaluated for their antiedematogenic and free radical scavenging activities. The ethanol extract and the hexane fraction produced statistically significant inhibition (74.4 and 76.0%, respectively) of the ear edema induced by croton oil in mice, observed at doses of 5 mg/ear. The ethyl acetate and hydroethanol fractions showed significant radical scavenging effect in the DPPH assay, with IC50 of 36.7 and 30.1 µg/mL, respectively. Fractionation of the extracts through chromatographic methods afforded epifriedelanol, oleanolic acid 3-O-acetyl, a mixture of stigmasterol 3-β-O-glucopyranoside and sitosterol 3-β-O-glucopyranoside, kaempferol 3,7-O-α-dirhamnopyranoside, kaempeferol-3-O-α-rhamnopyranoside and 2-O-methyl-chiro-inositol. The compounds were identified on the basis of their NMR spectral data and comparison with those of literature.

Com o propósito de aumentar a atividade anticâncer demonstrada anteriormente pelas 1-fenilssubstituído-3-(2-tioxo-1,3,4-oxadiazol-5-il) β-carbolinas 1a-c, neste trabalho foram realizadas a síntese e a avaliação in vitro da atividade antitumoral de novas bases de Mannich 2-7(a-c), derivadas da introdução de diferentes grupos alquilamino(metil) na unidade 1,3,4-oxadiazol de 1a-c. Os derivados 1a-c e 2-7(a-c) foram também avaliados quanto às atividades antibacteriana e antifúngica. Adicionalmente, um estudo in silico das propriedades de ADME dos novos compostos sintetizados 2-7(a-c) foi realizado pela avaliação de seus parâmetros de Lipinski e de dados de área de superfície topológica polar (TPSA) e de porcentagem de absorção (% ABS).

With the purpose of activity enhancement of 1-substituted phenyl-3-(2-thioxo-1,3,4-oxadiazol-5-yl) β-carbolines 1a-c, reported as potential antitumor agents in our previous study, herein we report the synthesis and antitumor activity evaluation of several novel Mannich bases 2-7(a-c), by the introduction of different alkylamino(methyl) groups in the 1,3,4-oxadiazole unity of 1a-c. The antimicrobial activities of 1a-c and of 2-7(a-c) were also evaluated. Additionally, an in silico study of the ADME properties of novel synthesized β-carboline derivatives 2-7(a-c) was performed by evaluation of their Lipinski's parameters and topological polar surface area (TPSA) and percentage of absorption (% ABS) data.

The phytochemical investigation of Guettarda pohliana roots led to the isolation of 28-O-beta-D-glycopyranosyl-3-O-beta-D-quinovopyranosyl quinovic acid, 28-O-beta-D-glycopyranosyl-3-O-beta-D-glycopyranosyl quinovic acid, 3-O-beta-D-glycopyranosyl quinovic acid, 28-O-beta-D-glycopyranosyl-3-O-beta-D-glycopyranosyl cincholic acid along with quinovic acid, daucosterol and 4,5-O-dicaffeoyl quinic acid. The structures of the isolated compounds were assigned on the basis of spectroscopic data, including two-dimensional NMR methods. The antiradical activity of the crude methanolic extract and of its fractions was evaluated.

The phytochemical investigation of Chomelia obtusa leaves led to the isolation of four triterpenes (3-O-β-D-quinovopyranosyl-28-O-β-D-glycopyranosyl quinovic acid, 3-O-β-D-quinovopyranosyl-28-O-β-D-glycopyranosyl cincholic acid, and a mixture of ursolic and oleanolic acids), two flavonoids (3-O-β-D-glycopyranosyl quercetin, 3-O-[α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside] quercetin), besides bornesitol and a mixture of 3,5- and 4,5-O-dicaffeoyl quinic acids. The structures of the isolated compounds were assigned on the basis of spectroscopic data, including two-dimensional NMR methods. The anti-inflammatory and antioxidant activities of the crude methanolic extract and of its fractions were evaluated. This is the first report on the chemical and biological investigation of the Chomelia genus.

Chemical investigation of the MeOH extract of the leaves of Machaonia brasiliensis (Rubiaceae) resulted in the isolation and identification of 3beta-O-beta-glucopyranosyl stigmasterol, 3beta-O-beta-glucopyranosyl sitosterol, secologanoside, 7-O-beta-glucopyranosyl quercetagetin, 4,5-O-dicaffeoylquinic acid and 5-O-caffeoylquinic acid. The structures of these compounds were established by spectroscopic analysis, including 2D NMR experiments. The chemotaxonomic relevance of the isolation of secologanoside is discussed.

Chemical investigation of the leaves of Alchornea glandulosa (Euphorbiaceae) afforded a mixture of b-sitosterol and stigmasterol, the terpenoid loliolide, the guanidine alkaloid N-1,N-2,N-3-triisopentenylguanidine and the phenolic compound corilagin. The structures of these compounds were elucidated by spectroscopic analysis. The antimicrobial and antiproliferative properties of the crude methanolic extract of the leaves and of fractions from its fractionation, were investigated against a series of bacteria and fungi, as well as against four human cancer cell lines.