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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. Keywords: Antispasmodic activity, Compounds isolation, GC–MS, Hemolytic assay, Ileum rat, Extract toxicity

A wood sample of Welwitschia mirabilis is reported to contain nerolidol and para-hydroxybenzaldehyde, besides two dehydroresveratrol dimers gnetins F and G and two dehydroresveratrol trimers gnetins H and I for which structures are proposed. Other oxidative resveratrol oligomers, gnetins A, B, C, D and E, have been isolated previously from three Amazonian Gnetum species. These facts provide welcome evidence for the discussion of relationships within the Gnetatae.

The extracts from leaves of Ocotea catharinensis Mez (Lauraceae) were found to contain fourteen neolignans and two sesquiterpenes: nine benzofuran types (including three new compounds 1e, 2f and 4b), one new seco-benzofuran type (3b), two bicyclo[3.2.1]octane types (including the new compound 5c), two new dimers of bicyclo[3.2.1]octane type (7a and 7b) and two sesquiterpenes (including a new humulanol 9). In addition, seven neolignans were also showed to occur in somatic embryos of O. catharinensis including one new bicyclo[3.2.1]octane type (4a). Foram isoladas de extratos de folhas de Ocotea catharinensis Mez (Lauraceae) quatorze neolignanas sendo nove benzofurânicas (incluindo três novas substâncias 1e, 2f e 4b), uma secobenzofurânica inédita (3b), duas biciclo[3.2.1]octânicas (incluindo a nova 5c), dois novos dímeros biciclo[3.2.1]octânicos (7a e 7b) e ainda dois sesquiterpenos (incluindo o novo humulanol 9). Nos embriões somáticos de O. catharinensis foram identificadas sete neolignanas incluindo uma nova neolignana biciclo[3.2.1]octânica (4a).

Plinia edulis (Myrtaceae), popularly known as "cambucá", is a Brazilian medicinal plant employed in the treatment of stomach problems and throat affections by the "caiçaras", fishermen of coastal localities. Aiming to contribute with the species knowledge the leaves of P. edulis were analyzed macro and microscopically and the chemical composition of the volatile oil was determined using a combination of GC/MS and retention indices. The antimicrobial assay and the phytochemical screening of the aqueous ethanol extract of the leaves have been performed to correlate the secondary metabolites and the traditional use. Leaves present morphological characteristics of others Myrtaceae species and some particularities, such as the circular idioblasts in number of 2 to 4, scattered perpendicularly at the adaxial surface, with druses or prismatic crystals. In the volatile oil fifteen components have been identified, of which epi-α-cadinol (21.7%), α-cadinol (20.2%) and trans-caryophyllene (14.2%) were major. The phytochemical screening of the aqueous ethanol extract showed the presence of substances with pharmacological interest, such as flavonoids, tannins, saponins and terpenoids but, despite of the presence of these classes, the extract did not inhibit the growth of Aspergillus niger, Candida albicans, Escherichia coli and Staphylococcus aureus in a concentration of 1,000 mg/mL. Plinia edulis (Myrtaceae), popularmente conhecida como "cambucá", é uma planta medicinal nativa do Brasil e empregada no tratamento de problemas estomacais e afecções de garganta por populações caiçaras. Buscando contribuir para o conhecimento da espécie, as folhas de P. edulis foram caracterizadas macro e microscopicamente e a composição química do óleo volátil foi determinada usando uma combinação de CG/EM e índices de retenção. O extrato hidroetanólico das folhas foi avaliado quanto ao perfil fitoquímico e à atividade antimicrobiana procurando-se a correlação dos metabólitos secundários e o uso tradicional. As folhas apresentam características morfológicas comuns a outras mirtáceas e algumas particularidades, como a presença de 2 a 4 idioblastos, contendo drusas e cristais prismáticos, dispostos perpendicularmente à face adaxial. No óleo volátil foram identificados 15 componentes, dentre os quais o epi-α-cadinol (21.7%), o α-cadinol (20.2%) e o trans-cariofileno (14.2%) foram os majoritários. A triagem fitoquímica do extrato hidroetanólico evidenciou a presença de substâncias de interesse farmacológico, tais como flavonóides, taninos, saponinas e terpenóides. No entanto, apesar da presença destas classes, o extrato não inibiu o crescimento de Aspergillus niger, Candida albicans, Escherichia coli e Staphylococcus aureus na concentração de até 1.000 mg/mL.

Passiflora alata Curtis, Passifloraceae, is a liana popularly known in Brazil as ‘maracujá-doce’ that has been used for treating different illnesses. Its leaves are described in the Brazilian Pharmacopoeia, but the gastroprotective activity has never been investigated. In the present study a freeze-dried crude 60% ethanol–water extract of P. alata aerial parts was prepared. Total flavonoid content, expressed as vitexin, was 0.67% ± 0.01. The hemolytic activity was 32 units for P. alata, using Saponin (Merck®) as reference. P. alata presented EC50 of 1061.2 ± 8.5 μg/ml in the 2,2-diphenyl-1-picryhydrazyl assay and 1076 ± 85 μmol Trolox/g in the Oxygen Radical Absorbance Capacity assay. P. alata, its solvent fractions and a P. alata nanopreparation were investigated for gastroprotective activity. The test samples exhibited gastroprotective activity on HCl/ethanol induced gastric mucosal lesions in rats. P. alata at doses of 100, 200 and 400 mg/kg, using the necrotizing agent at 150 mmol/l, inhibited 100% of ulcer formation (compared to the negative control), while lansoprazole (30 mg/kg) 77%. When tested against a more concentrated necrotizing agent (300 mmol/l), fractions of P. alata at 100 mg/kg reduced 57% (n-hexane), 34% (ethyl acetate) and 72% (aqueous fraction) the ulcer formation. In this assay, lansoprazole (30 mg/kg) inhibited 47%. When encapsulated, P. alata inhibited ulcer formation at 55%, 94% and 90% for dosages of 25, 50 and 100 mg/kg. These results suggest the potential use of P. alata as a gastroprotective herbal medicine. Keywords: Passiflora alata, Gastric ulcer, Passion flower, Flavonoids, Nanocapsules, Antioxidant

The labelled substrates phenylalanine and phenylpropanoid E-isoeugenol were incorporated to 5-methoxy-4-O-methyl-E-isoeugenol (E-isoelemicin) and to the tetrahydrofuran lignan verrucosin in plantlets of Virola surinamensis (Myristicaceae).Através de experimentos de administração in vivo em plântulas de Virola surinamensis, observaram-se as incorporações de fenilalanina e do fenilpropanóide E-isoeugenol no 4-O-metil-5-metoxi-E-isoeugenol (E-isoelemicina) e na lignana tetraidrofurânica verrucosina.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:48:49Z No. of bitstreams: 1 S0100-40422010000200017.pdf: 242505 bytes, checksum: 178d6611bc19b0615dbbe4e4a7a24d81 (MD5) Made available in DSpace on 2013-08-22T18:48:49Z (GMT). No. of bitstreams: 1 S0100-40422010000200017.pdf: 242505 bytes, checksum: 178d6611bc19b0615dbbe4e4a7a24d81 (MD5) Previous issue date: 2010-01-01 Made available in DSpace on 2013-09-30T19:10:48Z (GMT). No. of bitstreams: 2 S0100-40422010000200017.pdf: 242505 bytes, checksum: 178d6611bc19b0615dbbe4e4a7a24d81 (MD5) S0100-40422010000200017.pdf.txt: 22081 bytes, checksum: 5051bd1ddcb22e79dd8517f88ca4eb98 (MD5) Previous issue date: 2010-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:21:21Z No. of bitstreams: 2 S0100-40422010000200017.pdf: 242505 bytes, checksum: 178d6611bc19b0615dbbe4e4a7a24d81 (MD5) S0100-40422010000200017.pdf.txt: 22081 bytes, checksum: 5051bd1ddcb22e79dd8517f88ca4eb98 (MD5) Made available in DSpace on 2014-05-20T14:21:21Z (GMT). No. of bitstreams: 2 S0100-40422010000200017.pdf: 242505 bytes, checksum: 178d6611bc19b0615dbbe4e4a7a24d81 (MD5) S0100-40422010000200017.pdf.txt: 22081 bytes, checksum: 5051bd1ddcb22e79dd8517f88ca4eb98 (MD5) Previous issue date: 2010-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Phytochemical investigations on three Brazilian Lauraceae species from the Cerrado region of São Paulo State, Ocotea corymbosa (Meins) Mez., O. elegans Mez. and Persea pyrifolia Nees & Mart. ex Nees resulted in the isolation of flavonoids, an ester of the 4-O-E-caffeoylquinic acid, an aromatic sesquiterpene besides furofuran lignans. This is the first chemical study on the leaves of Ocotea elegans and O. corymbosa as well as the first report of non-volatile compounds from Persea pyrifolia. Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Química Departamento de Química Orgânica Instituto Nacional de Pesquisas da Amazônia Divisão de Química de Produtos Naturais Departamento de Produtos Naturais Centro de Biotecnologia da Amazônia Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Química Departamento de Química Orgânica

Chromatographic fractionation of the dichloromethane extract from roots of Virolasurinamensis yielded two new natural products, 3- epi -juruenolide C and2′-hydroxy-7,4′-dimethoxyisoflavone, as well as various known steroids, lignans, isoflavones,flavonoids and diarylpropanes. Of these, a,2′-dihydroxy-4,4′-dimethoxydihydrochalcone,biochanin A and 2′-hydroxy-7,4′-dimethoxyisoflavone displayed antifungal activity against Cladosporium cladosporioides at a minimum amount of 5 mg, whereas 7-hydroxyflavanone and7-hydroxy-4′-methoxyisoflavone exhibited an antifungal activity 10-fold higher than the positivecontrol Nystatin.

Plinia edulis, an arboreous species popularly known as "cambucá", is native to the Brazilian Atlantic Rain Forest. Despite its traditional uses, no reports are available on the safety of this utilization or on the relationship between the antiulcer activity of its extract and its phytochemical compounds. This paper reports on the investigation of the acute toxicity and gastroprotective effect of the aqueous ethanol extract of leaves of Plinia edulis on HCl/ethanol-induced ulcers. In order to correlate the secondary metabolites and the efficacy of the crude drug in traditional medicine, the extract was submitted to chromatographic fractionation after solvent partition. The extract did not show acute toxicity in mice treated with 5 g/kg p.o., but exhibited significant antiulcer activity in rats at doses of 100, 200, and 400mg/kg p.o., more active than the reference drug lansoprazole.The ethyl acetate fraction yielded beta-amyrin, oleanolic acid, ursolic acid, and maslinic acid, which were identified based on spectrometric analyses. Since antiulcerogenic activity is not restricted to one class of compounds in plants, the triterpenoids isolated in the extract can be associated with the observed effect.

A comparative phytochemical study between pericarps of Iryanthera lancifolia and Virola surinamensis showed that the first one contains a new pair of epimeric 2-alkenyl- γ -lactones, besides an aryltetralinic lignan and one tocotrienol, while the second species contains the lignans, galgravin and veraguensin, seven juruenolides : juruenolides C, D, F, G and epi -juruenolides D, F, G, together with three pairs of epimeric aliphatic 2-alkenyl- γ -lactones. Juruenolide F, epi -juruenolides D, F, G and the 2-alkenyl- γ -lactones are new natural compounds.

From the seeds of Virola surinamensis , which were collected near Altamira and near Maraba, Para State, Brazil, the following substances were isolated by chromatographic techniques: two dibenzylbutanediol lignans, dihydrocubebin and the new dihydrocubebin monolaurate, two furofuran lignans, sesamin and asarinin, three dibenzylbutyrolactol lignans, cubebin, β- O -methylcubebin and α- O -methylcubebin, one dibenzylbutyrolactone lignan, hinokinin, one aryltetralin neolignan, galbulin, two tetrahydrofuran neolignans, galgravin and the new ′4-hydroxy-′3-methoxy-3,4-methylenedioxy-8.8′,7. O .′7-neolignan, one flavone, tithonine, one isoflavone, irisolidone, and two new polyketides, 3-hydroxy- 1-(15- phenylpentadecanoyl)-2,6-cyclohexanedione and 1-(5-phenylpentanoyl)-2,6-cyclohexanedione. Different chemical constitutions of the fruits from the two localities were observed. © 1997 Published by Elsevier Science Ltd

The essential oil from leaves of Virola surinamensis shows circadian variation in elemicin and in monoterpenes during the rainy season (February). The monoterpenes represents 50% of total volatile compounds during the dry season (June). Sesquiterpenes are predominant (50%) in the early rainy season (October). © 1997 Published by Elsevier Science Ltd

Leaves and inflorescences of Iryanthera sagotiana were found to contain three known dihydrochalcones, two flavonol rhamnosides, four flavanonol rhamnosides, one dihydrocoumaric acid, besides the new 3′,3‴-bis-2′,4′,6′-trihydroxy-4-methoxydihydrochalcone and 4′,6′-dihydroxy-4-methoxydihydrochalcone-2′-O-β-d-glucopyranoside.

A hexane extract of Ocotea catharinensis leaves afforded by chromatographic fractionation, 11 neolignans, eight of the benzofuran-type (including three new compounds 1–3) and three of the bicyclo[3.2. 1]octane-type (including two new compounds 4 and 5).

The trunk wood and barks from an Aniba species contain four esters of benzoic acid with cinnamyl alcohol, five benzofuran neolignans, licarin-A, burchellin, cis -burchellin, burchellin-rearranged and cis -burchellin-rearranged, one tetrahydrofuran neolignan, aristolignin, three bicyclooctane guianin-type neolignans, (7 S , 8 S , 1′ R , 5′ R )-4-hydroxy-3,3′- dimethoxy-4′,6′-dioxo-8.1′, 7.5′-neolignan-Δ: 1,3,5,2′,8′ and the new (7 S , 8 S , 1′ R , 4′ R , 5′ S )-4′-hydroxy-3,4,3′-trimethoxy-6′-oxo-8.1′, 7.5′-neolignan-Δ: 1,3,5,2′,8′ and (7 S , 8 S , 1′ R , 4′ R , 5′ S )-4,4′-dihydroxy-3,3′-dimethoxy-6′-oxo-8.1′, 7.5′-neolignan-Δ: 1,3,5,2′,8′, one new bicyclooctane canellin-type neolignan (7 S , 8 S , 1′ S , 4′ R , 5′ R , 6′ S )-4′,6′-dihydroxy-3,4-dimethoxy-3′-oxo-8.1 ′, 7.5′-neolignan-Δ: 1,3,5,8′, two styrylpyrones, 4-methoxy-6-(11,12-dimethoxy- trans -styryl)-2-pyrone and 6-(11,12- methylenedioxy- trans -styryl)-4-methoxy-2-pyrone, two styrylpyrone dimers: 4′-methoxy-8-(11,12-dimethoxyphenyl)-7-[6-(4- methoxy-2-pyronyl)-6-( E )-styryl-1′-oxabicyclo[4,2,O]octa-4′-en-2′-one and the new 11,12-dimethoxyphenyl-7, 7′-di-[6-(4-methoxy-2-pyronyl)]-cyclobutane and six flavonoids, 3,5-dihydroxy-7,4′-dimethoxyflavone,5-hydroxy-3,7,4′ -trimethoxyflavone, 3,5,4′-trihydroxy-7-methoxyflavone, 2,3-dihydro-5-hydroxy-7,4′-dimethoxyflavone, 2,3-dihydro-3,5- dihydroxy-7-methoxyflavone, 2,3-dihydro-3,5-dihydroxy-7,4′-dimethoxyflavone and a new flavan, 6,7,3′,4′,5′-pentamethoxyflavan. © 1997 Elsevier Science Ltd. All rights reserved

The leaves and seeds of Virola surinamensis contain 17 lignans; fragansins A2 and D2, galbacin, galbelgin, 5-methoxygalbelgin, grandisin, verrucosin, aristolignan, austrobailignan, calopeptin, veraguensin, 5-methoxyveraguensin, nectandrin B, galbulin and galcatin; three propiophenone derivatives; two γ-lactones; juruenolide C and juruenolide D. Three lignans, one γ-lactone and one propiophenone are new natural products.

Unripe fruits of Ocotea corymbosa contain the known monoterpenes carvacrol and cis-3-hydroxy-p-menth-1-en-6-one, besides three novel rearranged sesquiterpenes possessing the apparently rare carbon skeleton of 10-desmethyl-1-methyl-eudesmane.

Fruits of Iryanthera grandis were found to contain two new pairs of diastereoisomeric flavonolignoids of the 1,4-diaryl-2,3-dimethyl-n-butyldihydrochalcone type.

Among the 35 neolignans isolated from bark and leaves of Ocotea porosa , 20 (including eight new compounds) belong to 12 benzofuranoid types, 11 (including six new compounds) belong to eight bicyclo[3.2.1]octanoid types and four (including one new compound) belong to four 1,2-diaryl- and 1-aryl-2-cyclohexylpropanoid types. All compounds are considered to originate through oxidative coupling of isoeugenol and eugenol and, in some relatively rare cases, of two isoeugenol units.

Propenylphenol plus allylphenol derived hydrobenzofuranoids, obtained by synthesis or from natural sources, are used to demonstrate evolution on the micromolecular level. Such neolignans carry sufficient information to instruct self-replication, as well as the replication of the other intermediates of cyclic reaction sequences. Modulation of temperature and acidity lead on to structural alternatives which compete with the intermediates of the cycles for starting material.

The Trunk Bark Of Nectandra Grandiflora, Of Southern Brazil, Contains Four Aporphine Alkaloids, Laurolitsine, Laurotetanine, Boldine and Isoboldine, In Addition To The Sesquiterpene Costic Acid. Preliminary Studies With An Alcohol Extract Of The Bark Revealed Antitumour Activity Against The Sarcoma 180 and Ehrlich's Carcinoma Models.

Five new compounds were isolated from fruits of Iryanthera paraensis : (2 S ,3 R )-5-methoxy-3-methyl-2-(4-hydroxy-3-methoxy-phenyl)-7-propenyl- 2,3-dihydro-benzo[1,4]dioxane, (2 S ,3 S ,4 S )-2-(9′-phenyl- n -nonyl)-3-hydroxy-4-methyl-butanolide; (2 S ,3 R ,4 S )-2-(9′-phenyl- n -nonyl)-3-hydroxy-4-methyl-butanolide; (2 S ,3 R ,4 S )-2-(11′-phenyl- n -undecyl)-3-hydroxy-4-methyl-butanolide; and (2 S ,3 R ,4 S )-2-(11′-phenyl- n -undecyl)-3-hydroxy- 4-methyl-butanolide.

A hexane extract of the trunk wood of Licaria brasiliensis contained ten bicyclooctanoid neolignans, including six new representatives belonging to the 4-oxy-8-oxo-, 4-oxo-8-oxy- and 4,8-dioxy-l-allyl-6-aryl-3,5- dimethoxy-7-methylbicyclo[3.2.1]oct-2-ene series.

Virola venosa contains 5-deoxyflavones in its flowers, unripe fruits (pericarps) and seedlings (leaves). Upon ripening progressively larger quantities of gradually more strongly reduced lignans, including the novel (-)-dihydro-3′,4′-dimethoxy-3′,4′-demethylenedioxycubebin, appear in all parts of the fruits. Dibenzyllactols, including, (-)-cubebin, and the furofuran, (+)-sesamin, are the major lignans, respectively, of mature seeds and seedlings (roots).

the use of electrochemical oxidation was applied to the synthesis of dibenzocyclooctadiene lactones related to steganacin skeleton. This reaction, performed with compounds 1 and 2, led to results comparable with the oxidation with RuTFA, TTFA and VOF3.

Iryanthera laevis , I. ulei and I. paraensis contain a series of novel lignoflavonoids the formation of which can be rationalized by the cinnamylation of the phloroglucinol type A-ring of a dihydrochalcone. The lignoid attachments of the flavonoid moieties consist of an arylvinylmethyl group in iryantherin-A, of 1,4-diaryl-2,3-dimethyl- n -butyl groups in iryantherins B and C and of 3-aryl-2-cinnamyl- n -propyl groups in iryantherins D and E. The construction of iryantherin-F requires oxidative addition of the vinyl unit of an iryantherin-A type compound to the A-ring of a second dihydrochalcone moiety.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:16Z No. of bitstreams: 1 S0100-46702005000300002.pdf: 257186 bytes, checksum: 92fc2838ebf083b3f97d28e2b2f4350f (MD5) Made available in DSpace on 2013-08-22T18:49:16Z (GMT). No. of bitstreams: 1 S0100-46702005000300002.pdf: 257186 bytes, checksum: 92fc2838ebf083b3f97d28e2b2f4350f (MD5) Previous issue date: 2005-09-01 Made available in DSpace on 2013-09-30T19:39:32Z (GMT). No. of bitstreams: 2 S0100-46702005000300002.pdf: 257186 bytes, checksum: 92fc2838ebf083b3f97d28e2b2f4350f (MD5) S0100-46702005000300002.pdf.txt: 20819 bytes, checksum: 6d029d978c0bf3ef37c70c56c4fbd7d9 (MD5) Previous issue date: 2005-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:18:58Z No. of bitstreams: 2 S0100-46702005000300002.pdf: 257186 bytes, checksum: 92fc2838ebf083b3f97d28e2b2f4350f (MD5) S0100-46702005000300002.pdf.txt: 20819 bytes, checksum: 6d029d978c0bf3ef37c70c56c4fbd7d9 (MD5) Made available in DSpace on 2014-05-20T14:18:58Z (GMT). No. of bitstreams: 2 S0100-46702005000300002.pdf: 257186 bytes, checksum: 92fc2838ebf083b3f97d28e2b2f4350f (MD5) S0100-46702005000300002.pdf.txt: 20819 bytes, checksum: 6d029d978c0bf3ef37c70c56c4fbd7d9 (MD5) Previous issue date: 2005-09-01 Testes em placas de CCDC reveladas com solução de beta-caroteno mostraram a presença de duas substâncias com propriedades antioxidantes no extrato hexânico. Elas foram isoladas e identificadas como 3-metil-sargacromenol (1) and sargacromenol (2). O extrato hexânico forneceu ainda o ácido 3-metil-sargaquinóico (3) e o ácido sargaquinóico (4). O comportamento eletroquímico destas substâncias foi investigado em CH2Cl2/Bu4NBF4 sobre eletrodo de carbono vítreo. A oxidação do grupo fenólico nos tocotrienóis 1 and 2 é responsável por um pico anódico em potenciais de +0.23V e +0.32V, os quais são correlacionados com sua atividade antioxidante. O mecanismo de oxidação é comparado com o comportamento eletroquímico do antioxidante alfa-tocopherol. TLC autographic assays revealed in the hexane extract of Iryanthera juruensis (Myristicaceae) the presence of two compounds, with antioxidant properties towards beta-carotene. They were isolated and identified as 3-methyl-sargachromenol (1) and sargachromenol (2). Further investigation of the hexane extract led to isolations of 3-methyl-sargaquinoic acid (3) and sargaquinoic acid (4). The electrochemical behaviour of these compounds was studied in CH2Cl2/Bu4NBF4 at glassy carbon electrode. The phenolic group in both tocotrienols 1 and 2 are oxidized at +0.23V and +0.32V and their oxidation potentials are correlated with the observed antioxidant activities and oxidation mechanism of alpha-tocopherol. The reductive voltametric behaviour of quinone function in both plastoquinones 3 and 4 is discussed. Universidade Estadual Paulista Instituto de Química Universidade Estadual Paulista Instituto de Química

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:19Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:29:29Z : No. of bitstreams: 1 2-s2.0-23744439433.pdf: 147891 bytes, checksum: 4d0a97a4d06dcf1d552dddb27ce7dcc2 (MD5) Made available in DSpace on 2014-05-27T11:21:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-05-01 The EtOH crude extract from the leaves of Nectandra grandiflora collected in the Atlantic Forest, Brazil, showed antioxidant activity towards β-carotene in a TLC assay. The bioassay-guided fractionation led to the isolation of protocatechuic acid and two flavonol glycosides: afzelin and quercetrin, which showed free radical scavenging activity towards DPPH (ΔA 32, 16 and 73% at 50 μmol L-1) and were compared to commercial antioxidants rutin (81% at 50 μmol L-1) and BHT (9% at 50 μmol L-1), used as standard compounds. Additionally, three inactive neolignans, including the new bicycle[3.2.1]octane neolignan 2′-oxo-piperol B were obtained and characterized by spectrometric methods. ©2005 Sociedade Brasileira de Química. Instituto de Química Universidade Estadual Paulista, CP 355, 14801-900 Araraquara - SP Instituto de Química Universidade de São Paulo, CP 26077, 05513-970 São Paulo - SP Instituto de Pesquisas da Amazônia, CP 476, 69083-000 Manaus - AM Instituto de Química Universidade Estadual de Campinas, CP 6154, 13084-971 Campinas - SP Instituto de Química Universidade Estadual Paulista, CP 355, 14801-900 Araraquara - SP

A phytochemical investigation in plantlets of the Brazilian medicinal tree Virola surinamensis resulted in the isolation and structural determination of four new compounds: 3-hydroxy-4-methyl-2-(11� -piperonyl-n-undecyl)butenolide; 3-hydroxy-4-methyl-2-(7� -piperonyl-n-heptyl)-butanolide; 9� -(3,4-methylenedioxy-phenyl)-nonanoic acid and 13� -(3,4-methylene-dioxyphenyl)-tridecanoic acid. Thirteen compounds previously isolated from seeds and adult plants were also reported.

Five new compounds were isolated from fruits of Iryanthera paraensis : (2 S ,3 R )-5-methoxy-3-methyl-2-(4-hydroxy-3-methoxy-phenyl)-7-propenyl- 2,3-dihydro-benzo[1,4]dioxane, (2 S ,3 S ,4 S )-2-(9′-phenyl- n -nonyl)-3-hydroxy-4-methyl-butanolide; (2 S ,3 R ,4 S )-2-(9′-phenyl- n -nonyl)-3-hydroxy-4-methyl-butanolide; (2 S ,3 R ,4 S )-2-(11′-phenyl- n -undecyl)-3-hydroxy-4-methyl-butanolide; and (2 S ,3 R ,4 S )-2-(11′-phenyl- n -undecyl)-3-hydroxy- 4-methyl-butanolide.

The labelled substrates phenylalanine and phenylpropanoid E-isoeugenol were incorporated to 5-methoxy-4-O-methyl-E-isoeugenol (E-isoelemicin) and to the tetrahydrofuran lignan verrucosin in plantlets of Virola surinamensis (Myristicaceae). Através de experimentos de administração in vivo em plântulas de Virola surinamensis, observaram-se as incorporações de fenilalanina e do fenilpropanóide E-isoeugenol no 4-O-metil-5-metoxi-E-isoeugenol (E-isoelemicina) e na lignana tetraidrofurânica verrucosina.

A new tetrahydrofuran lignan, the (+)-(7 S ,8 R ,8′ R )-3′,4′-dimethoxy-3,4-methylenedioxy-7,9′-epoxylignan-9-ol, was isolated from kernels of germinated seeds of Virola michelii , besides 10 previously described lignans: (+)-sesamin, (+)-fargesin, (+)-phillygenin, (−)-hinokinin, (−)-kusunokinin, (−)-dimethylmatairesinol, (+)-lariciresinol dimethyl ether, (−)-dihydrocubebin, (−)-2,3-desmethoxy- seco -isolintetralin and (−)-3′,4′,-dimethoxy-3′,4′-desmethylenedioxycubebin.

Bark of Ocotea pulchella contains, besides 1-( p -methoxybenzoyl)-6,7-methylenedioxyisoquinoline, 1-(hydroxy- p -methoxybenzyl)-6,7-methylenedioxyisoquinoline and their 1,2-dihydro-derivatives, 11-eudesmen-4α-ol and 4-furanoeudesmen-6-one.

The phytochemical investigation of the hexane extract of Iryanthera juruensis (Myristicaceae) fruits led to the isolation of two tocotrienols and four lignans which exhibited antioxidant activity towards β-carotene on TLC autographic assay. Two inactive quinones and three ω-arylalkanoic acids were also isolated. The isolates were investigated for their redox properties using cyclic voltammetry. The structure elucidation of the new compounds (one tocotrienol, one quinone and three ω-arylalkanoic acids) was based on analysis of spectroscopic data.

The presence of benzyl benzoates as well as of bicyclo [3.2.1] octanoid and hydrobenzofuranoid neolignans in Aniba ferrea was confirmed by the isolation of additional representatives of this class of natural products. The hydrobenzofuranoids included three novel ferrearins which, considered together with four known ferrearins, led to the stereochemical clarification of the group.

Bark and wood ofOcotea porosa contained eight new bicyclo [3.2.1]octanoid neolignans belonging to therel-(1′R,4′S,5′R,7S, 8R-Δ2′, 8′-4′-acetoxy-6′-oxo-8.1′,7.5′-neolignan, therel-(1′R,4′R,5′R,7R,8S)-Δ2′,8′-4′-acetoxy-6′-oxo-8.1′,7.5′-neolignan and therel-(1′R,5′S,6′R,7S,8R)-Δ2′,8′-3′,5′-dioxy-4′-oxo-8.1′,7.5′-neolignan series.

Eleven 6-[omega-arylalkenyl]-5,6-dihydro-alpha-pyrones, cryptomoscatones D2, E1, E2, E3 and F1 and cryptopyranmoscatones A1, A2, A3, B1, B2 and B4, in addition to goniothalamin and cryptofolione, were isolated from branch and stem bark of Cryptocarya moschata, Lauraceae. Their structures were established by spectroscopic methods.

The Amazon Indians Waiapi living in the West of Amapa State of Brazil, treat malaria with an inhalation of vapor obtained from leaves of Viola surinamensis. The essential oil obtained from adult and plantlet leaves was analyzed by GC/MS and 11 monoterpenes, 11 sesquiterpenes and three phenylpropanoids were identified. Plantlet essential oil caused 100% of growth inhibition after 48 h in the development of the young trophozoite to schizont stage and the sesquiterpene nerolidol (100 μg/ml) was identified as one of the active constituents (100% of growth inhibition was obtained). In addition, examination of [U14C]-glucose incorporation showed that activity of nerolidol is related to the inhibition of glycoprotein biosynthesis.

An extract from the pericarps of I. lancifolia afforded two dihydrochalcones (1 and 2) and two flavonolignans (3 and 4), with compounds 2-4 being of novel structure. The antioxidant activities of compounds 1-4 were evaluated through the measurement of malondialdehyde production, and Q(1/2) (concentration necessary for 50% inhibition of autoxidation) data were calculated. The Q(1/2) values obtained for 1-4 and the standard compounds alpha-tocopherol and quercetin were 6.9, 4.7, 5.5, 4.8, 12.1, and 7.6 microg/mL, respectively.

A benzene extract of the bark of Virola calophylla yielded, besides eight neolignans of the dibenzylbutane, benzoylbenzylbutane, aryltetralin and arylnaphthalene types, two new arylnaphthalenes, (8 R )-3,4-dimethoxy-3′,4′-methylenedioxy- > 7′8′ - 6.7′,8.8′-neolignan and 4-hydroxy-3-methoxy-3′,4′-methylenedioxy- > 7,8,7′,8′ -6.7′,8.8′-neolignan.