Synthesis and screening of 3-substituted thioxanthen-9-one-10,10-dioxides.

This manuscript describes methods appropriate for the parallel synthesis of libraries based on the tricyclic thioxanthen-9-one-10,10-dioxide scaffold. The novel compounds were synthesized from previously reported 3-chlorothioxanthen-9-one-10,10-dioxide and commercially available 3-carboxylic acid thioxanthen-9-one-10,10-dioxide. The library members were screened for activity in a fluorescence polarization assay for inhibitors of BRCT domains of breast cancer gene 1 and in cell-based secreted alkaline phosphatase reported replicon system for activity against hepatitis C virus.

Intramolecular 1,3-dipolar cycloadditions of dihydroimidazolium ylides: synthesis of pyrrolo[1,2,3-de]quinoxalines and imidazo[1,2-a]indoles.

N-Alkylation of 4,5-dihydroimidazoles with alkene-containing bromomethyl ketones and treatment of the so-formed 4,5-dihydroimidazolium ions with DBU gives rise to an intramolecular 1,3-dipolar cycloaddition reaction that affords (via a reaction cascade involving eliminative ring-opening, recyclisation and prototropic tautomerism) unexpected hexahydropyrrolo[1,2,3-de]quinoxaline products. Steric bulk in both the dihydroimidazole and the dipolarophile allows isolation of an imidazo[1,2-a]indole, the initial product of cycloaddition. When the bromomethyl ketone contains no other functionality, or when cycloaddition is inhibited due to steric constraints, the dihydroimidazolium ion undergoes ring-opening hydrolysis followed by recyclization of the exposed amino ketone to afford either 3-alkyl-1-formylpiperazine-2-ones or 3-aryl-1-formyl-1,4,5,6-tetrahydropyrazines.

Resistência de cultivares de algodoeiro ao vírus do Mosaico das Nervuras transmitido pelo pulgão Aphis gossypii (Glover) (Hemiptera: Aphididae) / Resistance of cotton cultivars to the Vein Mosaic Virus transmitted by the aphid Aphis gossypii (Glover) (Hemiptera: Aphididae)

O pulgão Aphis gossypii Glover é vetor da Virose Mosaico das Nervuras (V.M.N.), que pode ocasionar na cultura do algodoeiro, produção reduzida ou nula. O objetivo do estudo foi identificar cultivares de algodoeiro resistentes a V.M.N. quando expostas à ação de pulgões. Os experimentos foram conduzidos na fazenda experimental do Instituto Agronômico do Paraná, IAPAR, Londrina, PR, sendo o delineamento estatístico em blocos casualizados. As cultivares comparadas foram: Delta Opal, Deltapine A90, CNPA ITA 90, Coodetec 401, IAC 22, IPR 95, IPR 96 e IPR 94. Para avaliação foram selecionadas 25 plantas observando-se a presença de pulgões e sintomas de V.M.N. Dois experimentos foram realizados nas mesmas condições, sendo que em um deles realizaram-se aplicações de inseticidas, para o controle dos pulgões, quando sua presença foi constatada em 10 por cento das plantas. O outro experimento não recebeu aplicação de inseticidas para controle de pulgões. A presença do vetor foi constatada em plantas de todas as cultivares. Observou-se que, mesmo com menor infestação de pulgões na cultivar CNPA ITA 90, ocorreram elevados índices de V.M.N. com redução de 68 por cento da produção quando comparada com Delta Opal. As cultivares Delta Opal e Coodetec 401 mostraram-se muito resistentes a V.M.N. pela ausência de plantas com sintomas, IAC 22 foi susceptível, enquanto Deltapine A90 e CNPA ITA 90 foram muito susceptíveis. Os inseticidas ofereceram proteção razoável à ação do vetor, mas os dados permitem inferir que em áreas com elevados níveis de infecção de V.M.N., o método de controle mais adequado seria a adoção de cultivares resistentes à enfermidade como Delta Opal e Coodetec 401.

The aphid Aphis gossypii Glover is a vector of Cotton Vein Mosaic Virus (V.M.N.), which can cause reduced or null yields in cotton crops. The objective of this study was to identify cotton cultivars resistant to V.M.N. when exposed to the action of aphids. The experiments were conducted at the experimental farm of the Instituto Agronômico do Paraná, IAPAR, in Londrina, PR, Brazil, in a randomized blocks statistical design. The cultivars compared were: Delta Opal, Deltapine A90, CNPA ITA 90, Coodetec 401, IAC 22, IPR 95, IPR 96, and IPR 94. Twenty-five plants were selected for evaluation; the presence of aphids and V.M.N. symptoms were recorded. Two experiments were conducted under the same conditions; in one of them, insecticides were applied to control aphids when their presence was detected on 10 percent of the plants. The other experiment received no insecticides for aphid control. The vector was present on the plants from all cultivars. High V.M.N. rates occurred in cultivar CNPA ITA 90 even under lower aphid infestations, with a yield reduction of 68 percent when compared with Delta Opal. The cultivars Delta Opal and Coodetec 401 proved very resistant to V.M.N. based on the absence of plants with symptoms; IAC 22 was susceptible, while Deltapine A90 and CNPA ITA 90 were very susceptible. The insecticides provided reasonable protection against the action of the vector, but data allowed to infer that in areas with high levels of V.M.N. infection, the most suitable control method would be the adoption of cultivars resistant to the disease, such as Delta Opal and Coodetec 401.

Water sorption isotherms of Beauveria bassiana (Bals.) Vuill. Conidia / Isotermas de sorção de água de conídios de Beauveria bassiana (Bals.) Vuill

One of the requirements for successful commercial production of biological control agent is the maintenance of viability for long periods at room temperature, increasing shelf life. The water activity (Aw) is an important parameter to study the stability in the storage of dehydrated products but its determination demands equipments not always available. The water sorption isotherms correlate the Aw with the moisture of a product; adsorption isotherm is important to define the packaging system, and desorption isotherm the drying process. The objective of this study was to determine the sorption isotherms of Beauveria bassiana conidia and adjust them using a mathematical model. The adsorption and desorption were determined by gravimetric technique at 25°C and data were adjusted by the BET model. During desorption, conidia initially presented high moisture content (98 percent in dry basis) and Aw (0,93); from 98 percent to 50 percent a low reduction in Aw was observed, because the water was in a free form. When moisture was around 50 percent, a small reduction on moisture resulted in a great decrease in Aw, because the water was in a bound form. The adsorption curve showed that when moisture varied from 9 percent to 50 percent a small increment in conidia moisture resulted in a high increment in Aw. The BET model adequately represented the sorption isotherms of B. bassiana conidia, being useful to define the ideal moisture to storage this biological control agent.

Um dos requisitos para o sucesso na produção comercial de agentes de controle biológico é manter sua viabilidade por longos períodos, em condições não controladas, aumentando a vida de prateleira. A atividade de água (Aw) é um parâmetro importante no estudo da estabilidade no armazenamento de produtos desidratados, mas sua determinação direta exige equipamentos nem sempre disponíveis. As isotermas de sorção de água correlacionam Aw com a umidade de um produto; a isoterma de adsorção é importante para definir o sistema de embalagem e a de dessorção o processo de secagem. O objetivo deste trabalho foi determinar as isotermas de sorção de conídios de Beauveria bassiana e ajustá-las utilizando um modelo matemático. A adsorção e a dessorção foram determinadas por técnica gravimétrica a 25ºC e os dados ajustados pelo modelo de BET. Na dessorção, inicialmente os conídios apresentaram alto conteúdo de umidade (98 por cento em base seca) e Aw (0,93); de 98 por cento a 50 por cento foi observada uma baixa redução na Aw, pois a água estava na forma livre. Quando a umidade estava em torno de 505, uma pequena redução na umidade resultou em grande depressão na Aw, pois a água estava na forma ligada. A curva de adsorção mostrou que quando a umidade variou de 9 por cento a 50 por cento um pequeno aumento na umidade dos conídios resultou num grande acréscimo na Aw. O modelo de BET representou adequadamente as isotermas de sorção dos conídios de B. bassiana, sendo útil no estudo do armazenamento do patógeno.

On Coquilleitidia crassipes, a new record for Macau, with a key to adults of the subgenera and species groups of the genus.

Coquillettidia (Coquillettidia) crassipes is recorded for the 1st time in the Territory of Macau, southern China. The systematics of the genus is examined, new species groups are proposed, and a key to subgenera and species groups of Coquillettidia is provided.

The effect of Ca2+ antagonists on spontaneous motility from sheep duodenum.

Longitudinal smooth muscle of the sheep duodenum showed a rhythmic spontaneous activity with an average frequency of 5.6 +/- 0.55 phasic movements min-1 and a mean value of the amplitude of phasic contractions of 0.956 +/- 0.1 g. When the strips were incubated in Ca(2+)-free medium, the spontaneous motility amplitude (SMA) was reduced to 37 +/- 8.2% of control values. In Ca(2+)-free medium plus EDTA (1 or 2 mM), the SMA was strongly reduced to 21.9 +/- 8.3 and 1.8 +/- 1.8%, respectively. Verapamil, nifedipine and diltiazem diminished the SMA. The EC50 value for verapamil was 10(-9) M, whereas that for diltiazem was 2 x 10(-9) M and for nifedipine was 3 x 10(-14) M. Trifluoperazine and TMB-8 reduced the SMA with EC50 values of 7 x 10(-6) and 3 x 10(-5) M, respectively. The spontaneous activity in the sheep duodenum seemed to be mediated by influx extracellular Ca2+, which enters through potential-dependent channels and intracellular Ca2+ release.