Três novos derivados ciclopentenodiônicos e a conhecida cumarina xantiletina foram isoladas das raízes de Piper carniconnectivum. As estruturas foram estabelecidas por RMN 1D e 2D e por espectrometria de massas.Three new natural cyclopentenedione derivatives (1-3) and the known coumarin xanthyletin (4) were isolated from the roots of Piper carniconnectivum. The structures were established by spectroscopic data, mainly 1D and 2D NMR and EIMS.

Background: The use of humic substances as plant biostimulants has been increasingly attracting farmers and stunning researchers. The ability of these substances to enhance root growth by changing root architecture is often linked to their hormonal activities, such as auxin effects and nitric oxide production. Humeomics accesses the molecular constituents of humic substances, revealing the importance of alkyl components because of their conformations and chemical activities. Here, we describe the alkamides present in humic acids and compare their bioactivities using plasma membrane H + -ATPase activity level as a biochemical marker.Methods: Humic acids isolated from vermicompost were analyzed using 13 C and 15 N nuclear magnetic resonance spectroscopy. The unbound fraction was extracted with ethyl acetate and submitted to gas chromatography coupled to mass spectrometry to detect the presence of N-isopropyldecanamide. We synthesized N-isopropyldecanamide and treated maize seedlings for 7 and 15 days with different concentrations. The root growth and plasma membrane H + -ATPase activity were monitored. Nitric oxide accumulation in the lateral roots was imaged using 4,5-diaminofluorescein diacetate. The results were compared with those obtained for seedlings treated with humic acids isolated from vermicompost. Results:The amide functional group produced the only nitrogen signal in the 15 N humic acid resonance spectrum and similar alkamide moieties were found in the unbound humic extract through comparisons using gas chromatography coupled to mass spectrometry. The synthesis of N-isopropyldecanamide had few steps and produced a high yield (86%). The effects of N-isopropyldecanamide on root growth were concentration dependent. High concentrations (10 −4 M) enhanced root growth after 15 day of diminishing shoot biomass. However, low concentrations (10 −8 M and 10 −6 M) promoted root growth at 7 and 15 days, similar to the humic acid-induced plasma membrane H + -ATPase activity. Both N-isopropyldecanamide and humic acids enhanced nitric oxide accumulation during lateral root emergence. Conclusion:We described for the first time the effects of N-isopropyldecanamide on the plasma membrane H + -ATPase activity in maize seedling roots and compared its effects with those caused by humic acids. N-Isopropyldecanamide was detected in the unbound fraction of the humic supramolecular assembly, indicating that the putative hormone-like effects of these substances result also from the presence of this new class of plant regulators, in addition to other molecules.

Recebido em 24/11/10; aceito em 21/2/11; publicado na web em 12/5/11 EFFECT OF DRYING-AIR TEMPERATURE ON CONTENT AND CHEMICAL COMPOSITION OF THE ESSENTIAL OIL OF Pectis brevipedunculata. Leaves and flower heads of P. brevipedunculata were submitted to four drying-air temperatures (room temperature, 40, 50 and 60 °C). Room temperature (approximately 30 °C) and higher temperature drying (50 and 60 °C) had a deleterious effect on the essential oil content. The recommended drying-air temperature for the species is 40 °C for it results in the same amount of essential oil observed in fresh cut plants. Overall, 13 components accounting for more than 92% of the total composition were identified. Citral was the major component, followed by α-pinene and limonene. The essential oil showed high toxicity against Artemia salina larvae.Keywords: Pectis brevipedunculata; lemon-scented grass; citral. INTRODUÇÃOA família Asteraceae compreende 1.100 gêneros e cerca de 25.000 espécies que podem ser encontradas com frequência em regiões tropicais, subtropicais e temperadas, tanto ao nível do mar, como em montanhas, mas, na maioria das vezes, ocorrem em terrenos arenosos e rochosos.1 A espécie Pectis brevipedunculata (Gardner) Sch. Bip., família Asteraceae e subfamília Asteroideae, é uma planta de porte pequeno, rica em óleo essencial e nativa de ambiente xerófilo. No município de Campos dos Goytacazes, RJ, esta espécie surge espontaneamente em gramados, terrenos sem uso e em campos não cultivados. Sua ocorrência foi também registrada na restinga de Carapebus, RJ, e nas regiões do alto e médio Araguaia, MS, o que, neste último caso, não coincide com outros levantamentos florísticos de ambientes alagados. Estudos sobre a composição química dos óleos essenciais das partes aéreas de outras espécies do gênero Pectis, P. apodocephala e P. oligocephala mostraram a presença de monoterpenos. Ambos foram testados em juvenis de segundo estádio recém-eclodidos (J2) do nematoide Meloidogyne incognita e em larvas do terceiro ínstar do mosquito Aedes aegypti. Os resultados mostraram que os óleos podem ser considerados potenciais agentes nematicida e larvicida naturais.3 O estudo comparativo do óleo essencial de três espécimens de P. brevipedunculata coletadas em três estados diferentes, Rio de Janeiro, Espírito Santo e Ceará, mostrou que os componentes majoritários são neral, geranial e limoneno. 1Levantamentos preliminares feitos pelos autores revelaram que, em Campos dos Goytacazes, o chá da parte aérea de P. brevipedunculata é comumente usado pela população buscando efeito calmante. Ações calmantes e espasmódicas suaves são atribuídas ao citral que, de acordo com a literatura, é o principal componente da P. brevipedunculata. 4O estudo de plantas medicinais raras ou pouco conhecidas está sendo novamente considerado de alta relevância, devido à redescoberta de que o elo existente entre plantas e saúde humana tem sido responsável pelo lançamento de uma nova geração de produtos terapêuticos baseados no uso de insumos vegetais, o que inclui medicame...

Most cinnamic acids, their esters, amides, aldehydes, and alcohols present several therapeutic actions through anti-inflammatory, antitumor, and inhibitory activity against a great variety of microorganisms. In this work, eight amines derived from cinnamic acid were synthesized and tested against host cells infected with Toxoplasma gondii and the bacteria Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and three strains of Staphylococcus aureus. Compounds 3 and 4 showed the best result against intracellular T. gondii, presenting antiparasitic activity at low concentrations (0.38 and 0.77 mM). The antibacterial activity of these compounds was also evaluated by the agar microdilution method, and amides 2 and 5 had a minimum inhibitory concentration of 250 µg mL−1 against two strains of S. aureus (ATCC 25923 and bovine strain LSA 88). These also showed synergistic action along with a variety of antibiotics, demonstrating that amines derived from cinnamic acid have potential as pharmacological agents.

1-Deoxynojirimycin (1) is a natural alkaloid with several biological activities; the analog N-butyl-1-deoxynojirimycin (4), for example has shown potent anti HIV-1 and HIV-2 activity without cytotoxicity. As part of a program to synthesize compounds with biological activity against retroviruses, we developed an efficient route for the preparation of 1 and 4 employing as raw material glucose and others inexpensive reagents.The polyhydroxylated piperidine alkaloid 1-deoxynojirimycin (1), and its derivatives have been studied in numerous scientific investigations because they have demonstrated interesting antidiabetic, 1 anticancer, 2 anti-HIV I and HIV II 3 properties.The N-butyl derivative 4 has been shown to possess potent inhibitory activity of glycosidase enzymes, 4 and within a group including several natural and synthetic amino sugars and bicyclic alkaloids such as the indolizidine castanospermine and pyrrolizidine alexine, it presented the highest cytopathic effect (CPE) at a concentration which did not demonstrate cytotoxicity. 3 This compound is under clinical evaluation as an agent for the chemotherapy of AIDS. 5The compound 1-deoxynojirimycin (1) can be obtained from nojirimycin 6 and L-sorbofuranose 7 by varied chemical transformations. This alkaloid has also been isolated from natural sources such as plants of the genus Morus (Mori cortex, 8 Morus bombycis 9 ) and strains of Bacillus. 10 Regarding synthetic procedures for obtaining 1 and its derivatives, we can cite three different preparative strategies: the first involves as starting materials natural aldohexoses and ketohexoses; 11-16 the second employs a large number of steps using as starting material a chiral C 2 -symmetrical diol, the readily available diethyl L-tartarate; 17 and the third approach uses enzymes to build the skeleton of the desired alkaloid 1. 18,19 The latter synthetic methodology and related techniques of research represent a special field in modern synthetic organic chemistry involving microbiology, biochemistry and immunochemistry; these enantioselective syntheses have been developed employing enzymes isolated from mammals and bacteria. 20,21 The step of ring-closure to make piperidine alkaloids developed by some groups employed dicarbonyl sugar intermediates 22,23 with reductive amination to generate the desired diastereoisomer with high stereoselectivity, initiated by the attack of hydrogen from the bottom face resulting in the formation of the C 4 -C 5 bond in the more favorable trans configuration. As part of a research program to produce anti-retrovirus drugs with potential biological activity we were stimulated by all these representative results to design a straightforward and inexpensive synthesis to deoxynojirimycin (1) and N-butyl-1-deoxynojirimycin (4) employing reductive amination as the key step.The synthesis of 1 and 4 started with 2,3,4,6-tetra-O-benzyl-α-glucopyranose (5) which was converted to the desired 1,5-diol 6, in the form of a colorless viscous syrup, in quantitative yield, by reduction of the hemiketa...