A complete and unambiguous assignment of 1H and 13C nuclear magnetic resonance (NMR) signals of 29 naphthoquinones is reported on the basis of one- and two-dimensional NMR techniques (1H, 13C, 1H-1H correlated spectroscopy (COSY) and 1H-13C heteronuclear multiple-bond correlation (HMBC)). This is the first report distinguishing data between para-naphthoquinones, ortho- and para-furanonaphthoquinones isomers.

The resistance of Annona muricata roots to the nematode Meloidogyne javanica was investigated by nuclear magnetic resonance (NMR)-based metabolomics in combination with principal component analysis (PCA). Metabolic changes in roots exposed and not exposed to the nematode were evaluated and compared. In addition, the presence of nematicidal compounds in the root extracts was investigated through in vitro assay against Meloidogyne javanica second-stage juveniles. Plants exposed to nematodes showed significant changes in their metabolism after 24 h. Several resistance-related metabolites, including dopamine, xanthine and aromatic compounds, could be identified in the roots with the joint analysis of 1D/2D NMR and the loadings of PC3 (17.8%). A.muricata root chloroform extract, containing mainly acetogenins, has shown nematostatic activity against M. javanica, suggesting that a pre-formed defense mechanism can support the reported resistance. For the first time, metabolomic studies allowed to identify induced and pre-formed defense mechanisms and their related metabolites in Annona muricata.

The anaerobic decomposition in landfills produces a gas mixture known as landfill biogas. This biogas consists mainly of CH4 and CO2. The CO2 removal can be carried out by means of adsorption. In order to promote CO2 removal, zeolite type 4A was used as solid adsorbent. The synthesized zeolite was characterized by scanning electron microscopy and X-ray diffraction. CH4/CO2 mixture isotherms were obtained in a magnetic suspension balance equipped with a gas dosing unit and Extended Langmuir and Extended Sips models were used to predict mixture isotherms from monocomponent data. Three biogas emissions drains in a sanitary landfill in Caucaia (Ceará State, Brazil) - ASMOC - were chosen to test the performance of zeolite as CO2 adsorbent under real conditions. Zeolite 4A has proven to be very selective for CO2 even in the presence of H2S.

Lupeol, a triterpene frequently found in Asteraceae plant species, showed moderate to low activity in different strains of Plasmodium falciparum, the most virulent malaria etiological agents. In this work, lupeol was isolated from Parahancornia fasciculata, a plant that is used to treat malaria in the Amazonia region. In the search of more activity lupeol derivatives, five new 1,2,3-triazole hybrid molecules were synthetized by copper-catalyzed azide-alkyne cycloaddition. The antiplasmodial activity of the semi-synthetic compounds were evaluated by the lactate dehydrogenase assay; the lupeol propargyl ether was the only one to disclosing increased activity (half maximal inhibitory concentration-IC50-62.0 ± 1.92 µmol L-1) in relation to lupeol (IC50 117.00 µmol L-1). Therefore, this work revealed a new class of interesting lupeol derivatives that can be obtained by linking electron donors to the hydroxy group at C-3.

Este trabalho descreve a síntese de neoglicoconjugados diméricos, triméricos e tetraméricos derivados de D-galactose. O ligante monossacarídico foi preparado em cinco etapas utilizando-se a modificação de Doebner da reação de Knoevenagel na etapa de extensão da cadeia lateral. O ligante foi acoplado a 1,4-butanodiamina, tris-(2-etilamino)amina, pentaeritritiltetramina e dendrímeros PAMAM (núcleo 1,4-butanodiamina G0 e núcleo 1,12-dodecanodiamina G0). Os glicodendrímeros desprotegidos foram purificados por cromatografia por exclusão de tamanho (SEC). Esta foi a única etapa em que um método cromatográfico foi empregado em toda rota sintética. Essa é uma estratégia nova e eficiente para a preparação de neoglicoconjugados.

In this work, the synthesis of dimeric, trimeric and tetrameric D-galactose-based neoglycoconjugates is reported. The monosaccharide ligand was prepared in 5 straightforward steps from D-galactose using the Doebner modification of the Knoevenagel reaction for chain elongation. The ligand was coupled to 1,4-butanediamine, tris-(2-ethylamino)amine, pentaerythrityltetramine and PAMAM dendrimers (1,4-butanodiamine core G0 and 1,12-dodecanediamine core G0). The unprotected glycodendrimers were purified by size-exclusion chromatography (SEC). This was the only step in which a chromatographic method was employed throughout the synthetic route. This is a new and efficient strategy for the preparation of neoglycoconjugates.

O copolímero poli(3-hidroxibutirato-co-ε-caprolactona) foi sintetizado por transesterificação, a partir dos homopolímeros PHB e PCL, usando acetilacetonato de zircônio(IV), como catalisador, nas concentrações de 20, 50 e 80% de PHB em massa. Os copolímeros foram caracterizados por GPC, métodos espectroscópicos (RMN-¹H, RMN-13C e IV-FT) e métodos térmicos (TG e DSC). A rota de síntese utilizada mostrou-se eficaz na síntese dos copolímeros P(HB-co-CL), os quais mostraram diminuição das cadeias poliméricas, apresentando Mw inferior a 24.000Daltons. Todos os copolímeros obtidos são termicamente mais estáveis que o PHB e com menor cristalinidade que os homopolímeros de partida. Esses materiais são bons candidatos para utilização como biomateriais em matrizes para liberação controlada de fármacos ou mesmo como compatibilizante em blendas PHB/PCL.

In the present work, the copolymer poly(3-hydroxybutyrate-co-ε-caprolactone), P(HB-co-CL), was prepared by transesterification reaction from PHB and PCL. Zirconium (IV) acetylacetonate was used as catalyst and the copolymers were obtained in a wide range of compositions of PHB/PCL (20/80, 50/50, 80/20). These copolymers were characterized by GPC, FT-IR, ¹H-NMR, 13C-NMR, TG, and DSC. The copolymers had weight average molecular weight less than 24.000 Daltons. All the systems were thermally more stable than PHB, showing lower crystallinity than the homopolymers. These materials are good candidates to be used as biomaterials, in drug release matrices, or even as PHB/PCL blends compatibilizers.

Duas saponinas triterpênicas foram isoladas do extrato etanólico das raízes de Chiococca alba (L.) Hitch. (Rubiaceae). Suas estruturas foram elucidadas por RMN de ¹H e 13C 1D e 2D e por espectrometria de massas de alta resolução com ionização por eletronebulização como 3-O-β-D-glucopiranurosil-3-β-hidroxiolean-12,15-dien-28-oato de O-α-D-apiofuranosil (1→3)- [α-D-apiofuranosil (1→4)]-α-L-rhamnopiranosil (1→2)-α-L-arabinopiranosila (1) e 3-O-β-D-glucopiranurosil-3-β-hidroxiolean-12,15-dien-28-oato de 28-O-α-D-apiofuranosil (1→3)-α-L-rhamnopiranosil (1→2)-α-L-arabinopiranosila (2).

Two triterpene saponins were isolated from the ethanolic extract of the roots of Chiococca alba (L.) Hitch (Rubiaceae). Their structures were determined by ¹H and 13C 1D and 2D NMR and high resolution electrospray mass spectrometry as 3-O-β-D-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-α-D-apiofuranosyl (1→3)-[α-D-apiofuranosyl (1→4)]-α-L-rhamnopyranosyl (1→2)-α-L-arabinopyranosyl ester (1) and 3-O-β-D-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-α-D-apiofuranosyl (1→3)-α-L-rhamnopyranosyl (1→2)-α-L-arabinopyranosyl ester (2).

A reação de biotransformação da digitoxigenina (1) por Cochliobolus lunatus foi investigada. Foram realizados experimentos com duração de 4 dias, que resultaram no isolamento de quatro produtos, cujas estruturas químicas foram elucidadas como sendo 1beta-hidroxidigitoxigenina (2), 7beta-hidroxidigitoxigenina (3), 8beta-hidroxidigitoxigenina (4) e digitoxigenona (5). A obtenção desses produtos nas condições empregadas nunca foi anteriormente descrita. A produção da substância 4 em uma reação de biotransformação também é inédita.

The biotransformation of digitoxigenin (1) by Cochliobolus lunatus was investigated. The biotransformation reaction was carried out in a 4-day process, resulting in the isolation of four products, whose structures were elucidated as 1beta-hydroxydigitoxigenin (2), 7beta-hydroxydigitoxigenin (3), 8beta-hydroxydigitoxigenin (4) and digitoxigenone (5). The production of these derivatives under the employed conditions has never been described so far. This is also the first report on the production of compound 4 by a biotransformation reaction.

7,2'-Di-hidroxiisoflavona apresentou atividade contra tripomastigotas sanguíneos do Trypanosoma cruzi, agente etiológico da doença de Chagas, o que motivou a síntese de derivados anfifílicos de potencial utilização como quimioprofilático para esterilização de sangue para transfusão. Esta substância foi obtida por desmetilação da 7-hidroxi-2'-metoxiisoflavona, sintetizada via desoxibenzoína, seguindo-se eterificação com epicloridrina e abertura do anel oxirânico com dietilamina para levar à 7-oxipropanolamina, a qual, por tratamento com iodeto de metila, forneceu o sal de amônio correspondente. Nos ensaios in vitro com tripomastigotas sanguíneos do T. cruzi, a 7-hidroxi-2'-metoxiisoflavona foi inativa e a 7-oxipropanolamina foi mais ativa do que a 7,2'-di-hidroxiisoflavona. Já o sal de amônio, não só não eliminou completamente o parasita do sangue como causou lise total dos eritrócitos. Portanto, o sal de amônio não é adequado para o uso como profilático na transmissão do T.cruzi por transfusão sangüínea. A atividade tripanossomicida da 7,2'-di-hidroxiisoflavona e do seu derivado 7-oxipropanolamina estimulam a avaliação in vivo destas substâncias como potenciais quimioterápicos para tratamento da doença de Chagas, sendo necessários alguns gramas destas substâncias que poderão ser obtidos pelos processos simples descritos neste trabalho.

7, 2'-Dihydroxyisoflavone was shown to be active against the bloodstream trypomastigote form of Trypanosoma cruzi, the etiologic agent of Chagas' disease. Amphiphilic derivatives of this isoflavone were synthezised aiming to obtain hydrosoluble compounds of potential use as prophylactic agents to be added to blood for transfusion. This isoflavone was obtained by demethylation of 7-hydroxy-2'-methoxyisoflavone that was synthesized via the intermediate deoxybenzoin. Its reaction with epichlorohydrin, followed by aminolysis with diethylamine, afforded the 7-oxypropanolamine which on treatment with methyl iodide gave the corresponding ammonium salt. The 7-hydroxy-2'-methoxyisoflavone was inactive in the in vitro assays, the 7-oxypropanolamine was more active than 7, 2'-dihydroxyisoflavone while the ammonium salt has not eliminated the parasite from the blood besides causing total lysis of the erythrocytes. The simple synthetic procedures described in the present paper can be used to provide gram quantities of 7, 2'-dihydroxyisoflavone and its 7-oxypropanolamine derivative that should be further investigated in in vivo murine models as potential chemotherapeutic agents for treatment of Chagas' disease.

A biotransformação da digitoxigenina (1) por Fusarium ciliatum foi investigada. O cardenolídeo 1 foi obtido a partir da hidrólise ácida da digitoxina e a reação também forneceu os produtos secundários delta14-15-digitoxigenina (2) e delta8-14-digitoxigenina (3). A reação de biotransformação foi realizada em um período de 5 dias e três produtos foram isolados e identificados a partir de análises espectrométricas: digoxigenina (4), digoxigenona (5) e digitoxigenona (6). A obtenção dos dois últimos cardenolídeos nas condições empregadas é inédita. A investigação da cinética da reação de biotransformação indicou 6 como o primeiro produto a ser formado, seguido dos derivados hidroxilados 4 e 5, sugerindo o envolvimento de enzima distintas na hiroxilação em 12beta e na oxidação em C-3 da digitoxigenina (1). A reação de biotransformação também foi realizada com a digitoxina, mas F. ciliatum se mostrou incapaz de promover sua hidroxilação.

The biotransformation of digitoxigenin (1) by Fusarium ciliatum was investigated. The cardenolide 1 was obtained by the acid hydrolysis of digitoxin and the reaction also afforded two side products, identified as delta14-15-digitoxigenin (2) and delta8-14-digitoxigenin (3) by spectroscopic analysis. The biotransformation reaction was carried out in a 5 days process and three products were isolated and had their structures elucidated as digoxigenin (4), digoxigenone (5) and digitoxigenone (6). The investigation of the biotransformation kinetics disclosed 6 as the first derivative to be formed, followed by the more polar hydroxylated products 4 and 5, suggesting the involvement of different enzymes in 12beta hydroxylation and C-3 oxydation of digitoxigenin (1). The production of 5 and 6 under the employed conditions has never been reported. The biotransformation reaction was also undertaken with digitoxin, but F. ciliatum has been unable to promote its hydroxylation.

No âmbito de um programa de estudo de reações de macrociclização intramolecular de radicais arila de o-iodobenzamidas mediadas por hidreto de tri-n-butilestanho foi obtida a benzomacrolactama 2, proveniente de ciclização regiosseletiva 11-endo a partir de 4-O-alil-2,3-di-O-benzil-6-desoxi-6-(2-iodobenzoilamino)- α-D-galactopiranosídeo de metila (1). A benzamida 1 foi sintetizada a partir do α-D-galactopiranosídeo de metila em oito etapas. Da reação de 1 com hidreto de tri-n-butilestanho, além da macrolactama 2, foi isolado o produto de hidrogenólise 3. As estruturas das substâncias 1, 2 e 3 foram identificadas pelos seus espectros de RMN ¹H, RMN 13C e DEPT e por experimentos de RMN bidimensional (COSY e HMQC).

Encouraged by our previous studies of tri-n-butyltin-mediated radical cyclization reaction of o-iodobenzamides, we applied this methodology to the synthesis of benzomacrolactam 2 from methyl 4-O-allyl-2,3-di-O-benzyl-6-deoxy-6-(2-iodobenzoylamino)- α-D-galactopyranoside 1. Apart from the macrolactam 2, resulting from regioselective 11-endo aryl radical cyclization, the hydrogenolysis produt 3 was obtained. The o-iodobenzamide 1 was prepared in eight conventional synthetic steps from methyl α-D-galactopyranoside. The unequivocal structures of 1, 2 and 3 were supported by ¹H, 13C and DEPT NMR spectroscopy and by COSY and HMQC experiments.

Neste trabalho são descritos o isolamento e a identificação de eupafolina e hispidulina das folhas secas de Eupatorium littorale (Asteraceae). Foi desenvolvido também um método para a detecção desses flavonóides e de rutina na planta, utilizando a técnica de CLAE em fase reversa com detetor de arranjo de fotodiodos. Eupafolina e hispidulina foram quantificados sendo encontradas as concentrações de 0,29% e 0,21%, respectivamente.

The isolation and identification of eupafolin and hispidulin in the dried leaves of Eupatorium littorale (Asteraceae) are described. A method for the detection of those flavonoids and rutin was also developed using reversed-phase HPLC with a photodiode array detector. Eupafolin and hispidulin were quantified and the concentrations found were 0.29% and 0.21%, respectively.