Phytochemical investigation of the inflorescences of Dictyoloma vandellianum A. Juss. (Rutaceae) has led to the isolation of a new A-seco-limonoid, named dictyolomol (1), along with a known quinolone alkaloid, casimiroine (2), previously isolated from the same species. The structures were established by spectroscopic analysis such as one- and two-dimensional NMR, IR, high-resolution mass spectrometry and chemical transformations. The isolated compounds (1 and 2) and O-acetyl derivative (1a) were evaluated for their cytotoxicity against MCF-7 and HeLa cancer cell lines. The results indicated that 1, 1a and 2 showed no significant cytotoxicity.

The phytochemical investigation of Erythroxylum pulchrum St. Hil. (Erythroxylaceae) led to the isolation of three known flavonoid glycosides quercetin-3-O-α-L-rhaminoside, ombuin-3-ruthinoside and ombuin-3-ruthinoside-5-glucoside. These flavonoids are being described for the first time in this E. pulchrum. The structures of the compounds were determined by analysis of IR, MS and NMR data, as well as by comparison with literature data. The methanolic extract of leaves from E. pulchrum inhibited the growth of the Bacillus subtilis CCT 0516, Escherichia coli ATCC 2536, Pseudomonas aeruginosa ATCC 8027, P. aeruginosa ATCC 25619, Staphylococcus aureus ATCC 6538, S. aureus ATCC 25925, Streptococcus sanguinis ATCC 15300, S. salivarius ATCC 7073, S. mutans ATCC 25175 and Streptococcus ATCC. S. aureus ATCC 25925 was the most sensitive among the other S. sanguinis while S. salivarius proved the most resistant.

O estudo fitoquímico das folhas de Maytenus distichophylla Mart. ex Reissek levou ao isolamento de um novo triterpeno 3,16,21-trioxo-6β,12α-dihidroxi-1-en-friedelano, nomeado maytensifolona, juntamente com os triterpenos conhecidos, 3-oxofriedelano, 3,12-dioxofriedelano, 3β-hidroxifriedelano, 3-oxo-29-hidroxifriedelano, 3-oxo-12α-hidroxifriedelano e 3-oxo-30-hidroxifriedelano. A identificação estrutural foi baseada em métodos espectroscópicos e comparação com dados da literatura

Phytochemical study of the leaves of Maytenus distichophylla Mart. ex Reissek led to the isolation of the new triterpene 3,16,21-trioxo-6β,12α-dihydroxy-1-en-friedelane, named maytensifolone, along with the known triterpenes 3-oxofriedelane, 3,12-dioxofriedelane, 3β-hydroxyfriedelane, 3-oxo-29-hydroxyfriedelane, 3-oxo-12α-hydroxyfriedelane and 3-oxo-30-hydroxyfriedelane. Their structural identification was based on spectroscopic methods and comparison with literature data.

The phytochemical investigation of L. macrophylla Benth led to the isolation of a new flavanol named licanol: (-)-4'-O-methyl-epigallocatechin-3'-O-α-L-rhamnoside, along with nine known compounds, identified as: (-)-4'-O-methyl-epigallocatechin, pheophytin A, 13²-hydroxy-(13²-S)-pheophytin A, pheophytin B, sitosterol, stigmasterol, sitosterol-β-O-glucoside, betulinic alcohol and oleanolic acid. The structures were established based on IR, HR-ESI-MS, and NMR spectrometric data analysis with the aid of 2D techniques. The methanolic extracts of leaves and stem bark as well as the compounds licanol, 13²-hidroxi-(13²-S)-feofitina A, and betulinic alcohol demonstrated antimicrobial activity against several bacterial strains.

The new dibromotyrosine derivative 3,5-dibromo-4-[3'dimethylamonium]propoxyphenyl]-N,N,N-trimethylethanamonium, here referred to as aplysfistularine (1), was isolated from the marine sponge Aplysina fistularis along with 2-(3,5-dibromo-4methoxyphenyl)-N,N,N-trimethylethanamonium (2), aplysterol (3) and 24,28-didehydroaplysterol (4). Their identification was performed by mass spectrometry, infrared, ¹H and 13C NMR, and by comparison with literature data. Compound 2 and the mixture of 3 and 4 were tested in vitro (inhibitory activity) with supercoiled DNA relaxation techniques, and showed inhibitory activity on human DNA topoisomerase II-α. Compound 1 was not tested due to paucity of the material.

The Annonaceae family is distributed throughout Neotropical regions of the world. In Brazil, it covers nearly all natural formations particularly Annona, Xylopia and Polyalthia and is characterized chemically by the production of sources of terpenoids (mainly diterpenes), alkaloids, steroids, polyphenols and, flavonoids. Studies from 13C NMR data of diterpenes related with their botanical occurrence were used to generate self-organizing maps (SOM). Results corroborate those in the literature obtained from morphological and molecular data for three genera and the model can be used to project other diterpenes. Therefore, the model produced can predict which genera are likely to contain a compound.

Seven natural neolignans isolated from Licaria chrysophylla and Licaria aurea along with five semisynthetic derivatives were tested for their inhibitory action on DNA-topoisomerase by relaxation assays on pBR322 plasmid DNA. All compounds tested showed strong inhibition at a concentration of 100 µM, while none showed activity between 5 and 70 µM. These results indicate that no obvious correlation can be derived between the structure of these compounds and their inhibitory effect on the DNA relaxation activity of topoisomerase II. This is the first report on DNA topoisomerase II inhibitors from Licaria chrysophylla and Licaria aurea leading to the identification of lignoids as topoisomerase II-α inhibitors.

The phytochemical investigation of Rollinia leptopetala led to the isolation of a new compound named α-terpinyl caffeate, and five known compounds, being three sesquiterpenes, spathulenol, β-caryophyllene and 4β,10α-aromadendrane-diol, and two alkaloids, (-)-3-hydroxynornuciferine and (+)-norisocorydine. These alkaloids are being described for the first time in this genus. The structures of the compounds were determined by analysis of IR, MS and NMR data, as well as by comparison with literature data. The crude extract of R. leptopetala leaves demonstrated a weak cytotoxicity on sarcoma 180 cells with an IC50 of 512.3 µg/mL. However, the in vivo results showed that the extract exhibited a significant dose-dependent tumor growth reduction.

Danos aos tecidos devido ao estresse oxidativo estão diretamente ligados ao desenvolvimento de muitos, senão todos, os fatores de sedentarismo e de doenças crônicas. Neste contexto, a busca de moléculas naturais, que participam da nossa dieta e que possuam atividade antioxidante, flavonóides, torna-se de grande interesse. Neste estudo, nós investigamos um conjunto de 41 flavonóides (23 flavonas e 18 flavonóis), relacionando suas estruturas e atividade antioxidante. Os dados experimentais foram submetidos à análise de QSAR (relações quantitativas estrutura-atividade). Dados de RMN 13C foram utilizados para realizar um estudo do mapa auto-organizável de Kohonen, analisando o peso que cada carbono tem na atividade. Além disso, realizamos uma MLR (regressão múltipla) usando GA (algoritmos genéticos) e descritores moleculares para avaliar a influência de carbonos e substituições na atividade.

Tissue damage due to oxidative stress is directly linked to development of many, if not all, human morbidity factors and chronic diseases. In this context, the search for dietary natural occurring molecules with antioxidant activity, such as flavonoids, has become essential. In this study, we investigated a set of 41 flavonoids (23 flavones and 18 flavonols) analyzing their structures and biological antioxidant activity. The experimental data were submitted to a QSAR (quantitative structure-activity relationships) study. NMR 13C data were used to perform a Kohonen self-organizing map study, analyzing the weight that each carbon has in the activity. Additionally, we performed MLR (multilinear regression) using GA (genetic algorithms) and molecular descriptors to analyze the role that specific carbons and substitutions play in the activity.

Aldose Reductase (AR) is the polyol pathway key enzyme which converts glucose to sorbitol. High glucose availability in insulin resistant tissues in diabetes leads into an accumulation of sorbitol, which has been associated with typical chronic complications of this disease, such as neuropathy, nephropathy and retinopathy. In this study, 71 flavonoids AR inhibitors were subjected to two methods of SAR to verify crucial substituents. The first method used the PCA (Principal Component Analysis) to elucidate physical and chemical characteristics in the molecules that would be essential for the activity, employing VolSurf descriptors. The rate obtained explained 53% of the system total variance and revealed that a hydrophobic-hydrophilic balance in the molecules is required, since very polar or nonpolar substituents decrease the activity. Artificial Neural Networks (ANNs) was also employed to determine key substituents by evaluating substitution patterns, using NMR data. This study had a high success rate (85% accuracy in the training set and 88% accuracy in the test set) and showed polihydroxilations are essential for high activity and methoxylations and glicosilations primarily at positions C7, C3' and C4' decrease the activity.

Foi isolado das folhas de Nanuza plicata um novo biflavonóide, chamado 3',8"-biisocampferideo (1), juntamente com os conhecidos compostos amentoflavona (2), ácido patagônico(3),(4aR,5S,6R,8aR)-5-[2-(2,5-dihidro-5-metóxi-2-oxofuran-3-il)etil]-3,4,4a,5,6,7,8, 8a-octahidro-5,6,8a-trimetilnaftaleno-1-ácido carboxílico (4), cafeoilquinato de metila (5), ácido 3,5-di-cafeoilquínico (6) e luteolina (7). Os compostos 3, 4, 5 e 6 são relatados pela primeira vez em Velloziaceae. As estruturas dos compostos foram elucidadas com base em métodos espectroscópicos, especialmente RMN e EM. A citotoxicidade de 3',8"-biisocampferideo foi estudada em células de glioblastoma humano (GL-15). A concentração efetiva, que produziu morte em 50% das células após 72 h foi 36,5 µmol L-1. Alterações na morfologia celular, incluindo retração e degradação de citoplasma, foram observadas quando as células foram tratadas com concentrações a partir de 20 µmol L-1 de 3',8"-biisocampferideo por 72h.

A novel biflavonoid, named 3',8"-biisokaempferide (1), along with the known compounds amentoflavone (2), patagonic acid (3), (4aR,5S,6R,8aR)-5-[2-(2,5-Dihydro-5-methoxy-2-oxofuran-3-yl)ethyl]-3,4,4a,5,6,7,8,8a-octahydro-5,6,8a-trimethylnaphthalene-1-carboxylic acid (4), 5-caffeoylquinic acid methyl ester (5), 3,5-di-caffeoylquinic acid (6) and luteolin (7), were isolated of the leaves from Nanuza plicata. The compounds 3, 4, 5 and 6 are reported for the first time in Velloziaceae. The structures of the compounds were elucidated on the basis of spectroscopic methods, especially NMR and MS analyses. The cytotoxicity of 3',8"-biisokaempferide was studied in cultures of human glioblastoma GL-15 cells. The effective concentration, which killed 50 % of cells after 72 h was 36.5 µmol L-1. Changes in cellular morphology, including retraction and degradation of cytoplasm, were observed when cells were treated with concentrations from 20 µmol L-1 of 3',8"-biisokaempferide for 72 h.

The phytochemical investigation of Xylopia langsdorffiana led to the isolation of corytenchine, xylopinine, discretamine, xylopine, ent-atisan-16α-hydroxy-18-oic acid, 13² (S) hydroxy-17³-ethoxyphaephorbide and quercetin-3-α-rhamnoside. Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques. Antioxidant activities of discretamine were measured using the 1,2-diphenyl- 2-picryl-hydrazyl (DPPH) free radical scavenging assay.

Maytenus obtusifolia é utilizada na medicina popular para o tratamento de úlceras graves, inflamações gerais e câncer. Apesar da importância etnofarmacológica desta espécie, nenhum estudo foi realizado para avaliar a sua toxicidade e atividade antiulcerogênica. Neste estudo, nós avaliamos a toxicidade e propriedade antiulcera do extrato etanólico das folhas de Maytenus obtusifolia (MO-EtOH). O MO-EtOH (10-1000 µg/mL) mostrou baixa toxicidade para as larvas de A. salina com CL50 maior que 1000 µg/mL. O MO-EtOH (2000 mg/kg, p.o.) nγo alterou o peso corporal e peso dos órgãos dos camundongos, mas foi observado um aumento no consumo de água dos machos e uma diminuição do consumo alimentar das fêmeas. Durante o estudo não foram observadas mortes e nem alterações macroscópicas nos órgãos dos camundongos. MO-EtOH (62,5, 125, 250 e 500 mg/kg) e lansoprazol (30 mg/kg) reduziram significativamente o índice ulcerativo para 65,58 ± 8,74, 43,00 ± 9,53, 15,50 ± 7,56, 54,75 ± 8,88 e 36,13 ± 9,55, respectivamente, em comparação com salina 82,13 ± 12,48. Em conclusão, o MO-EtOH apresentou baixa toxicidade e atividade antiulcerogênica, o que confirma o uso popular de M. obtusifolia.

Maytenus obtusifolia is used in folk medicine for the treatment of serious ulcers, general inflammations and cancer. Despite of the ethnopharmacological importance of this species, no study was conducted to evaluate its toxicity and antiulcerogenic activity. In this study, we evaluated the toxicity and antiulcerogenic property of the ethanol extract of the leaves of Maytenus obtusifolia (MO-EtOH). The MO-EtOH (10-1000 µg/mL) showed low toxicity for larvae of A. salina with LC50 higher than 1000 µg/mL. The MO-EtOH (2000 mg/kg, p.o.) did not change the body and organs weight of the mice, but it was observed an increase in the water consumption of males and a decrease in the food consumption of females. During the study no deaths and no macroscopic changes in the organs were observed in the mice. MO-EtOH (62.5, 125, 250 and 500 mg/kg) and lansoprazole (30 mg/kg) significantly reduced the ulcerative index for 65.58 ± 8.74, 43.00 ± 9.53, 15.50 ± 7.56, 54.75 ± 8.88 and 36.13 ± 9.55, respectively, in comparison with saline 82.13 ± 12.48. In conclusion, the MO-EtOH showed low toxicity and antiulcerogenic activity, confirming the popular use of M. obtusifolia.

O óleo essencial das folhasde Rollinia leptopetala foi obtido por hidrodestilação em aparelho de Clevenger e a sua composição química foi analisada através de CG-EM. Com essa técnica, foi possível identificar 22 constituintes em uma mistura complexa demonoterpenos (54,5%) e sesquiterpenos (45,5%). O principal componente encontradonas folhas foi o biciclogermacreno (22,47%). O óleo essencial foi avaliado numa linhagem de Staphylococcus aureus portadora de bomba de efluxo responsável pela resistência norfloxacino. Embora o óleo essencial não tenha apresentado atividade antibacteriana relevante in vitro, ele apresentou atividade moduladora da resistência, ou seja, em combinação com o norfloxacino observou-se uma redução de 4x na concentração inibitória mínima do antibiótico, indicando inibição de bomba de efluxo.

The essential oil from the leaves of Rollinia leptopetala was obtained by hydrodistillation in Clevenger's apparatus and its chemical composition was analyzed by GC-MS. With this technique could be identified 22 constituents in a complex mixture of monoterpenes (54.5%) and sesquiterpenes (45.5%). The main component found in the leaves was the bicyclogermacrene (22.47%). The essential oil was assayed against a strain of Staphylococcus aureus possessing efflux mechanism of resistance to norfloxacin. Although the essential oil did not display relevant antibacterial activity in vitro, it modulated the activity of the norfloxacin, i.e. in combination with the antibiotic it was observed a fourfold reduction in the minimum inhibitory concentration for norfloxacin, indicating inhibition of efflux pump.

A família Aristolochiaceae apresenta entre seus constituintes terpenóides, alcalóides e lignóides. Papo-de-peru, jarrinha, mil-homens e capivara são nomes populares da espécie Aristolochia birostris, a qual é utilizada na medicina popular como antiofídica, sudorífica, anticatarral e abortiva. Um estudo fitoquímico anterior com as partes aéreas desta espécie reportou o isolamento de quatro terpenóides, um lignóide e uma antraquinona. Dando continuidade a esse estudo, este trabalho relata a identificação de 4 lignóides, sendo dois do tipo ariloxiarilpropânico (4-metilenodioxi-5,3',5' -trimetoxi-1'-alil-8.O.4'-neolignana e 3,4,5,3',5'-pentametoxi-1'-alil-8.O.4'-neolignana), um do tipo tetraidrofurano (grandisina) e uma lignana dibenzilbutirolactônica [(-)-hinoquinina], além de vanilina. As estruturas foram estabelecidas através de métodos espectroscópicos de infravermelho e ressonância magnética nuclear uni e bidimensionais. Os lignóides foram avaliados quanto a atividade antimicrobiana frente a algumas cepas de bactérias, fungos e leveduras, entretanto foram inativos.

The family Aristolochiaceae presents among its chemical constituents terpenoids, alkaloids and lignoids. Aristolochia birostris is a species of this family popularly known as "papo-de-peru", "jarrinha", "mil-homens" and "capivara", and it is used in the folk medicine to treat snake bites, as a sudorific, expectorant and abortive. A previous phytochemical study of the aerial parts of this plant reported the isolation of four terpenoids, lignoids and antraquinone. Continuing this study it is now reported the isolation of four lignoids, two of the type aryloxyarylpropane (4-methylenedioxy-5,3',5'-trimethoxy-1'-alyl-8.O.4' -neolignan and 3,4,5,3',5'-pentamethoxy-1'-alyl-8.O.4'-neolignan), one tetrahydrofuran (grandisin) and a dibenzylbutyrolactone lignans [(-)-hinokinin], and also vanillin. The chemical structures of the isolated compounds were established based on spectral data, mainly IR and NMR including 1D and 2D experiments. The lignoids were evaluated for their activity against some bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis and Escherichia coli), fungi (Aspergilus flavus and Microsporum canis) and yeast (Candida albicans, Candida tropicalis and Criptococcus neoformans), but they were inactive.