ABSTRACT
Abstract Remifentanil is a modern fentanyl analogue with ultrashort-action granted by an esterase-labile methyl propanoate chain. Here, we present the development of a continuous flow methodology for the key N-alkylation step of remifentanil preparation in a biphasic, "slug-flow" regime. We screened parameters under microwave-assisted reactions, translated conditions to flow settings, and obtained remifentanil under 15-min residence time in a 1-mL microreactor, with a space-time yield of 89 mg/mL·h and 94% yield.
Subject(s)
Pharmaceutical Preparations/analysis , Remifentanil/pharmacology , Analgesics, Opioid/antagonists & inhibitors , Continuous FlowABSTRACT
Abstract Methanolic extracts of the Brazilian endemic ascidian Eudistoma vannamei have been extensively studied for their cytotoxic activity against several human cancer cell lines. Previous work reported the occurrence of purine derivatives and staurosporine alkaloids as the major nitrogen-containing compounds. In this study, we report the occurrence of three pyrimidine alkaloids in addition to cholesterol, sitosterol and stigmasterol.
ABSTRACT
Recentemente especial atençäo tem sido dada sobre o possível envolvimento dos compostos estrogênicos como agentes etiológicos no desenvolvimento do câncer de mama. Estudos realizados, principalmente na década de 90 têm levantando a questäo de resíduos de organoclorados e suas possíveis associaçöes com câncer de mama. O presente estudo envolveu 46 casos e 152 controles. Os casos foram constituídos por mulheres que tinham tido câncer de mama e mastectomizados. Para cada caso foram pareadas três controles compostas por mulheres com características semehantes em relaçäo a idade e estilo de vida e que näo tinham nenhuma doença da mama. Os níveis de DDT foram determinados através de cromatografia em fase gaosa. OS resultados mostraram que os níveis de DDT total no soro sangüineo foram bastante semelhantes nos dois grupos (13,6 ppb ñ 9,6 para os casos de 15,9 ppb ñ 15,7 para os controles) e nenhuma diferença estatística foi encontrada. Os resultados näo apoiam a hipótese de que o DDT seja considerado um fator de risco para o câncer de mama. Investimentos em estudos ambientais säo necessários para quantificar a exposiçäo e para caracterizar as atividades biológicas de substâncias químicas no ambiente. Pesquisas dessa natureza aumentaräo a nossa compreensäo sobre as causas ambientais do câncer de mama e auxiliaräo a identificar as substâncias químicas com maior potencial para carcinogênese, cujos efeitos poderäo ser minimizados ou eliminados
Subject(s)
Humans , Female , Breast Neoplasms/etiology , DDT/adverse effects , DDT/blood , Insecticides, Organochlorine/adverse effects , Risk FactorsABSTRACT
The mussel Anodontites trapesialis (Lam, 1819) was used as an indicator of organochloride pollutans in the Canoas River, located in the municpality of Mococa (21-25'08"S and 47W), State of Säo Paulo, Brazil. Biological monitoring was performed for one year at the site of an orange grove on the left bank of the river. Forty-five animals were placed in aluminum enclosures on the river bottom at this site and 4 animals were sacrificed for pesticide analysis at 3-month intevals, each corrsponding to one season of the year. Pesticides were extracted by the method of Bedford et al., (1968), modified, and the analyses were performed bay gas phase chromatography equipped with an elelctron capture detector. The aninals were found to have been exposed to DDT. Lindane and Heptachlor. Variation in Aldrin and Dieldrin levels was not significant enough to permit inferences. Endrin was not detected in any of the analyses
Subject(s)
Animals , Environmental Monitoring , Insecticides, Organochlorine/analysis , Bivalvia/chemistry , Pesticide Residues/analysis , BrazilABSTRACT
Some informations about the sesquiterpene lactones isolated from Brazilian species of Vernonia are described, as well the results of tests developed with such compounds with respect to their anti-feedant, molluscicide, antimicrobial and analgesic properties.