A bilingual (English and Portuguese) innovative teaching method, Stereochemistry Game, is presented in the form of a board/card game to help students in their studies of stereochemistry. Four decks of cards (280 cards in total) and one board have been developed for second-year organic chemistry students in an effort to have them work together to solve stereochemistry problems in the context of a fun board game and to provide an efficient alternative to traditional methods of learning. This game encourages interaction and communication among students, develops strategic thinking, and requires minimal preparation and supervision from the professor. Based on the feedback of students and the assessment of learning, the game can be used as a complementary didactic tool by students for aiding them to review and to learn topics related to stereochemistry in a fun way.

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Three withaphysalins, rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-2,24-dienolide(withaphysalin M) (1), rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-18-ethoxy-1-oxowitha-2,24-dienolide (withaphysalin F ethyl ether, withaphysalin O) (2), and rel-(17S,20R,22R)-5 beta,6 beta:18,20-diepoxy-4 beta-hydroxy-1,18-dioxowitha-24-enolide (withaphysalin N) (3), were isolated from the leaves of Acnistus arborescens. The structures were deduced from 1D ((1)H NMR, (13)C NMR, DEPT-(13)C NMR) and 2D (COSY, HMQC, HMBC) NMR analysis and the relative stereochemical assignments based on 1D NOESY correlations and analysis of coupling constants. Compounds 1 and 2 displayed potent cytotoxic activity against a panel of human cancer cell lines.

The volatile composition of the essential oils from leaves and roots of Eupatorium betonicaeforme (D.C.) Baker was analyzed by GC-MS. A total of 12 compounds were identified. beta-Caryophyllene (12.4-41.7%), alpha-humulene (11.7-14.6%), gamma-muurolene (10.4-19.0%), bicyclogermacrene (15.0-17.5%), 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%), and 2-senecioyl-4-vinylphenol (8.5-41.0%) were the most prominent constituents. The former two compounds were isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti larvae survival. The results obtained show that the essential oil from roots and 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%) could be considered as natural larvicidal agents.

Recebido em 7/6/10; aceito em 11/8/10; publicado na web em 26/11/10 ANTIFUNGAL GLYCOALKALOIDS, FLAVONOIDS AND OTHER CHEMICAL CONSTITUENTS OF Solanum asperum Rich (Solanaceae). Two glycoalkaloids: solamargine and solasonine; three flavonoids: tiliroside, 7-O-α-L-ramnopyranosyl-kaempferol and, in addition to the tripeptide Leu-Ile-Val, the aminoacid proline and the eicosanoic acid were isolated from Solanum asperum (Solanaceae). The structures of all compounds were determined by interpretation of their spectra (IR, MS, 1 H and 13 C NMR) and comparison with the literature data. All compounds, except the glycoalkaloids, are being reported for the first time for S. asperum. Solasonine showed strong activity (MIC < 0.24 mg/mL) against four filamentous fungi species of the genera Microsporum and Trichophyton.Keywords: Solanum asperum; antifungal glycoalkaloids; flavonoids. INTRODUÇÃOA família Solanaceae é representada por aproximadamente 2000 espécies distribuídas em 95 gêneros, sendo o taxon Solanum o mais representativo, com aproximadamente 1500 espécies e 5000 epítetos. As plantas que representam este gênero estão distribuídas preferencialmente nas áreas tropicais e subtropicais do planeta, sendo a América do Sul, o centro de maior diversidade e distribuição. 1 Uma grande fração do total de espécies descritas pode ser encontrada no Brasil, particularmente, na região Nordeste, onde são catalogadas cerca de 350 espécies. 2 Várias plantas deste gênero são popularmente conhecidas como "jurubebas", muitas das quais são largamente utilizadas na medicina popular, especialmente no tratamento de doenças da pele ou doenças relacionadas ao fígado e baço. 3,4 As plantas do gênero Solanum destacam-se pela capacidade de biossintetizar esteroides e alcaloides, livres ou na forma de heterosídeos, metabólitos secundários estruturalmente diversificados e complexos. 5,6 Estes compostos, em geral, são de interesse terapêutico, visto que apresentam um grande leque de atividades, como citotóxica, 5 anticâncer, 7 anti-inflamatória, 8 antiulcerogênica 9 e moluscicida. 10 Além disso, são também responsáveis pela resistência natural das espécies em seu ecossistema. 11 Compostos fenólicos, principalmente flavonas e flavonóis, incluindo seus heterosídeos, são também identificados com frequência em espécies de Solanum. 1,12 Como parte de um estudo multidisciplinar, cujo objetivo é investigar plantas da família Solanaceae, na busca por compostos bioativos, especialmente com atividade anticâncer, já foram isoladas várias lactonas esteroidais. 13,14 Neste trabalho é relatado o resultado obtido com a prospecção química de Solanum asperum Rich, popularmente conhecido como "coça-coça" ou "russara". As plantas desta espécie apresentam porte arbustivo e todas as suas partes são pulverulentas, isto é, ricas em pelos urticantes que se desprendem facilmente e que, em contato com a pele, provocam intensa coceira, daí o nome popular. Concomitante ao estudo químico foi ainda investigado o potencial antifúngico de algumas das substâncias isoladas.

A chemically sulfated galactomannan (BRS) from seeds of Mimosa scabrella had in vitro antiviral activity against Herpes simplex virus 1 (HSV-1), but not against Simian rotavirus A/SA11 (SiRV-A/SA11). It was examined by (13)C NMR spectroscopy, which showed the sulfate groups to be mainly at C-6 of galactose residues. BRS had a selective inhibition against HSV-1 during its attachment step, having an IC(50) lower than 2.5microg/ml, determined by plaque reduction, and a selectivity index of greater than 181, suggesting that the antiviral effect is likely due to interactions between the virus and BRS, being influenced its overall surface charge.

Abstract:A new indole alkaloid, 12-hydroxy-N-acetyl-21(N)-dehydroplumeran-18-oic acid (13), and 11 known indole alkaloids: 3,4,5,6-tetradehydro-β-yohimbine (3), 19(E)-hunteracine (4), β-yohimbine (5), yohimbine (6), 19,20-dehydro-17-α-yohimbine (7), uleine (10), 20-epi-dasycarpidone (11), olivacine (8), 20-epi-N-nor-dasycarpidone (14), N-demethyluleine (15) and 20(E)-nor-subincanadine E (12) and a boonein δ-lactone 9, ursolic acid (1) and 1D,1O-methyl-chiro-inositol (2) were isolated from the EtOH extracts of different parts of Aspidosperma ulei Markgr. (Apocynaceae). Identification and structural elucidation were based on IR, MS, 6282Plasmodium falciparum. IC 50 values of 14.0 (39.9), 4.5 (16.7) and 14.5 (54.3) μg/mL (μM) were determined for 3, 11 and 12, respectively. Inhibitory activity of 3, 4, 11, 12 and 13 was evaluated against NIH3T3 murine fibroblasts. None of these compounds exhibited toxicity to fibroblasts (IC 50 > 50 μg/mL). Of the five compounds screened for in vitro antiplasmodial activity, only 11 was active.

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