No abstract

No abstract

Two new triterpene glucosides, β-d-glucopyranosyl 2α,3β,24-trihydroxyolean-12-en-28-oate and β-d-glucopyranosyl 2α,3β,23,24-tetrahydroxyurs-12-en-28-oate, in addition to nine known compounds belonging to three different triterpene classes (oleanane-, ursane- and lupane-type) have been isolated from the stems of a specimen of Combretum laxum growing in the “Pantanal” of the central-western region of Brazil. Among the known triterpenes, β-d-glucopyranosyl 2α,3β,6β-trihydroxyolean-12-en-28-oate is reported for the first time in the Combretaceae, while bellericoside and asiatic acid are described for the first time in the genus Combretum. The structures of the isolated compounds have been established on the basis of spectral techniques (1D-, 2D-NMR and MS). Their in vitro antifungal activities against standard strains of Candida albicans, C. krusei and Cryptococcus neoformans were also evaluated in this work.

The aim of our study was to explore the clinicopathological and prognostic significance of extracellular matrix metalloproteinase inducer (EMMPRIN) expression in oral squamous cell carcinomas (OSCC), and its relation with the proliferative tumor status of OSCC. We examined EMMPRIN and Ki-67 proteins expression by immunohistochemistry in 74 cases with OSCC. Statistical analysis was conducted to examine their clinicopathological and prognostic significance in OSCC. EMMPRIN membrane expression was observed in all cases, with both membrane and cytoplasmic tumor expression in 61 cases (82.4%). EMMPRIN overexpression was observed in 56 cases (75.7%). Moderately or poorly differentiated tumors showed EMMPRIN overexpression more frequently than well-differentiated tumors (P = 0.002). Overexpression of EMMPRIN was correlated with high Ki-67 expression (P = 0.004). In the multivariate analysis, EMMPRIN overexpression reveals an adverse independent prognostic value for cancer-specific survival (CSS) (P = 0.034). Our results reveal that EMMPRIN protein is overexpressed in more than two-thirds of OSCC cases, especially in high proliferative and less differentiated tumors. The independent value of EMMPRIN overexpression in CSS suggests that this protein could be used as an important biological prognostic marker for patients with OSCC. Moreover, the high expression of EMMPRIN makes it a possible therapeutic target in OSCC patients.

Da madeira e das cascas do caule de Terminalia fagifolia foram isolados dois 1,3-diarilpropanos, 1-(4'-hidróxi-2'-metóxifenil)-3-(3"-metóxi-4"-hidróxifenil)-propano e 1-(2'-hidróxi-4',6'dimetóxifenil)-3-(3"-metóxi-4"-hidróxifenil)-propano, sete flavanonas, naringenina, 5-hidróxi-4',7dimetóxiflavanona, sakuranetina, isosakuranetina, 7,4'-dimetóxiflavanona, 7-hidróxi-4'metóxiflavanona, 7-metóxi-4'-hidróxiflavanona, duas chalconas, 2',4'-diidroxi-4-metóxichalcona e 2'-4-diidroxi-4'-metóxichalcona, uma flavana, 7,4'-diidróxi-3'-metóxiflavana e nove triterpenos pentacíclicos, ácido arjúnico, arjunetina, arjungenina, arjunglucosídeo I, ácido arjunólico, arjunglucosídeo II, 23-galoilarjunglucosídeo (isolado como seus derivados mono-, die trimetilados após metilação com diazometano), ácido betulínico e acetato do ácido ursólico, além de ácido gálico e sitosterol. Os diarilpropanos representam os primeiros membros desta classe em Combretaceae e as flavanonas e chalconas estão sendo descritas pela primeira vez na família. As substâncias isoladas foram avaliadas quanto às atividades citotóxica in vitro (células Hep 2 e H 292 , carcinomas de laringe e mucoepidermóide de pulmão humanos, respectivamente) e antioxidante. As chalconas, o diarilpropano 1-(2'-hidróxi-4',6'-dimetóxifenil)-3-(3"-metóxi-4"-hidróxifenil)propano e os derivados die tri-metilados de 23-galoilarjunglucosídeo foram os mais ativos quanto à atividade citotóxica. Two 1,3-diarylpropanes, 1-(4'-hydroxy-2'-methoxyphenyl)-3-(3"-methoxy-4"hydroxyphenyl)-propane and 1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3"-methoxy-4"hydroxyphenyl)-propane, seven flavanones, naringenin, naringenin-4',7-dimethyl-ether, sakuranetin, isosakuranetin, liquiritigenin-4',7-dimethyl-ether, liquiritigenin-7-methyl-ether and liquiritigenin-4'-methyl-ether, two chalcones, isoliquiritigenin-4-methyl-ether and isoliquiritigenin-4'-methyl-ether, one flavan, 7,4'-dihydroxy-3'-methoxyflavan, nine triterpenes, arjunic acid, arjunetin, arjungenin, arjunglucoside I, arjunolic acid, arjunglucoside II, 23galloylarjunglucoside II (isolated as its mono-, di-and triO methyl derivatives after methylation with diazomethane), betulinic acid and ursolic acid acetate, along with gallic acid and sitosterol were isolated from the heartwood and trunk bark of of Terminalia fagifolia. The flavanones and chalcones obtained in the present work are new in the Combretaceae and this is the first report of the occurrence of 1,3-diarylpropanes in this family. The isolated compounds were evaluated for their in vitro cytotoxic activity against two human cancer cell lines (Hep 2 larynx carcinoma and H 292 lung mucoepidermoid carcinoma) and antioxidant properties. Isoliquiritigenin-4-methylether, isoliquiritigenin-4'-methyl-ether, 1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3"-methoxy-4"-hydroxyphenyl)-propane and the di-and triO methyl derivatives of 23-galloylarjunglucoside II were the most active in the cytotoxic assay.

Recebido em 19/5/08; aceito em 6/10/08; publicado na web em 2/2/09 PHENYLPROPANOIDS AND OTHER BIOACTIVE CONSTITUENTS FROM NECTANDRA MEGAPOTAMICA. From the trunk bark of Nectandra megapotamica (Lauraceae) four phenylpropanoids, elemicin, isoelemicin, (±)-erythro-1-(3,4,5-trimethoxyphenyl)-1,2-propanediol and (±)-threo-1-(3,4,5-trimetoxyphenyl)-1,2-propanediol have been isolated, in addition to 3,4,5-trimethoxybenzoic acid, (-)-epicatechin and trans-1(10)-epoxy-4(15)-caryophyllene. The diastereoisomeric erythro-and threo-phenylpropanoids are being reported for the first time in a plant taxon as well as the occurrence of the other compounds in Nectandra. The structures of the isolated compounds have been established on the basis of 1D and 2D NMR spectroscopic techniques. Their in vitro antifungal activities against standard strains of Candida albicans, C. krusei, C. tropicalis and Cryptococcus neoformans and antioxidant properties were also evaluated in this work.Keywords: Nectandra megapotamica; Lauraceae; phenylpropanoids. introduÇÃoA família Lauraceae engloba cerca de 52 gêneros e 3 mil espécies dispersos predominantemente nas regiões tropical e subtropical do planeta, especialmente nas matas centro-e sul-americanas, sendo excepcionalmente encontradas em zonas temperadas. No Brasil, é representada por 22 gêneros, compreendendo espécies em geral arbóreas. 1 Nectandra é um dos principais gêneros de Lauraceae no Novo Mundo, com 114 espécies distribuídas em todos os biomas da América tropical e subtropical, sendo encontrados no Brasil 43 representantes. 2 Em Mato Grosso do Sul foram relatadas 8 espécies de Nectandra (N. amazonum, N. cissiflora, N. cuspidata, N. falcifolia, N. gardneri, N. hihua, N. megapotamica e N. psammophila). 3 Nectandra megapotamica, conhecida popularmente por "canelapreta", ocorre desde o sul de Minas Gerais até o Rio Grande do Sul e também na região Centro-Oeste, sendo que em Mato Grosso do Sul é encontrada nas regiões central e sul do estado. 3,4 A literatura relata 5 trabalhos realizados com espécimes desta planta coletados no estado de São Paulo, 3 dos quais relacionados a atividades biológicas de alguns de seus constituintes químicos. Das cascas do caule foram obtidos dois alcalóides (N-metiltriptamina e 6-metóxi-N-metil-1,2,4-tetraidro-β-carbolina) inibidores do crescimento in vitro de Crithidia fasciculata e Trypanosoma cruzi. 5 Outro estudo realizado com as cascas do caule forneceu um fenilpropanóide (α-asarona) que apresentou atividade analgésica, além das neolignanas tetraidrofurânicas galgravina e veraguensina com atividade antiinflamatória em ratos e camundongos, enquanto que das folhas foram obtidas onze neolignanas tetraidrofurânicas, três das quais com atividade tripanocida in vitro. 6 A investigação da composição química de lauráceas que ocorrem no Cerrado e Pantanal de Mato Grosso do Sul, incluindo as do gênero Nectandra, tem sido motivo de estudos desenvolvidos por nosso grupo de pesquisa. 7 Nas coletas de plantas realizadas, constatamos a presença de Nectandra megapotamica ...

A total of 42 ethanolic extracts from 30 different plant species, native to the Pantanal and Cerrado of the West-Central region of Brazil, have been evaluated for their larvicidal activity against Aedes aegypti larvae, the vector of dengue and dengue hemorrhagic fevers. Among the extracts tested, that obtained from the trunk bark of Ocotea velloziana was the most active. Using a bioassay-directed fractionation of this extract, the active constituent was isolated and characterized as the aporphine alkaloid (+)-dicentrine. Its structure was established on the basis of (1)H and (13)C NMR spectra, optical rotation and by comparison with an authentic sample. This is the first report on the larvicidal activity against A. aegypti of this alkaloid. Our results suggest that (+)-dicentrine may be considered as a promising natural mosquito larvicidal agent.

Graphical abstract