Chemical Constituents, Larvicidal Effects and Radical Scavenging Activity of Tetracera breyniana Schltdl. (Dilleniaceae).

Extracts and fractions from the leaves and stems of Tetracera breyniana Schltdl. were evaluated against the fourth instar Aedes aegypti larvae and ability to scavenge free radicals. Fractions that provided the best results were fractionated on silica gel column to afforded three flavonoils (quercetin, 7-O-methylquercetin and 7-Omethylkaempferol) and two terpenoids (β-sitosterol and betulinic acid). These compounds were identified on basis of their physical and NMR spectral data and by comparison with literature data. With exception of quercetin, all other compounds are been described for the first time in the investigated species. In the larvicidal assays, when compared to synthetic insecticide Temephos, only hexane fraction from stem was effective (LD50 72.08 g/mL). In the DPPH assays, EtOAc fractions from the leaves (CI50 74.15 ± 14.73 g/mL) and stem (IC50 39.87 ± 13.46 g/mL), of which quercetin was isolated, showed the best results when compared with the positive standards used while CHCl3 fractions of both plant parts, of which methylated flavonols were isolated, showed only a moderate activity. Possibly these constituents are responsible in part for the radical scavenging activities observed. Subsequently, evaluation of all isolated compounds will be needed to confirm the active component.

Chemical constituents of Rourea doniana

The chromatography fractionation of the hexane, chloroform and ethyl acetate extracts from the leaves and stems of Rourea doniana Baker, Connaraceae, resulted in the isolation of five triterpenes (lupeol, lupenone, α-amyrenone, β-amyrenone, and taraxerol), a flavonol (7,4'-dimethylkaempferol), a coumarin (scopoletin) and four phytosteroids (β-sitosterol, stigmasterol, β-sitosteryl-3-O-β- D-glucopyranoside and stigmasteryl-3-O-β-D-glucopyranoside). All compounds are being for the first time in this species and all triterpenes and the flavonol are being described for the first time in the family Connaraceae. These compounds were identified on basis of their IR and NMR (¹H, 13C, DEPT, HSQC, HMBC, and NOESY) spectral data and by comparison with literature data.

Triterpenos de Guettarda grazielae M.R.V. Barbosa (Rubiaceae) / Triterpenes from Guettarda grazielae M.R.V. Barbosa (Rubiaceae)

O presente trabalho descreve o isolamento e a identificação estrutural de seis triterpenos (acetato de ±-amirina, cicloartenona, 3²,19±,23-triidroxi-urs-12-eno e os ácidos ursólico, 3-²-O-²-D-glicopiranosilquinóvico e 3²,6²,19±,23-tetraidroxi-urs-12-en-28-óico), além de um fitoesteróide (sitostenona) de extratos das folhas, cascas do caule e caule de Guettarda grazielae M.R.V. Barbosa (Rubiaceae). Os compostos isolados, exceto o ácido 3-²-O-²-D-glicopiranosilquinóvico, estão sendo descritos pela primeira vez no gênero Guettarda e foram identificados com base na análise de dados espectrais de RMN, incluindo APT e DEPT, bem como pela comparação com dados da literatura.

This work describes the isolation and structural identification of six triterpenes (a-amyrin acetate, cycloartenone,3²,19±,23-trihydroxyurs-12-ene,andursolic,3-²-O-²-D-glucopyranosylquinovic, 3²,6²,19±,23-tetrahydroxyurs-12-en-28-oic acids), beside a phytosteroid (sitostenone) from leaves, stem barks and stems of Guettarda grazielae (Rubiaceae). All isolated compounds, except 3-²-O-²-D-glucopyranosylquinovic acid, are being described for the first time in the genus Guettarda and were identified on basis of the spectral NMR data, including APT and DEPT, as well as by comparison with data of the literature.

Constituintes químicos das folhas e do caule de Coccoloba mollisCasaretto (Polygonaceae) / Chemical constituents from leaves and stem of Coccoloba mollis Casaretto (Polygonaceae)

O estudo químico das frações neutra em hexano das folhas e em diclorometano do caule de Coccoloba mollis resultou no isolamento de um triterpeno pentacíclico (simiarenol), que pela primeira vez ocorre em Polygonaceae, dois fitoesteróides (sitostenona e sitosterol), um diterpeno (trans-fitol) e de um benzenóide (ácido vanílico) que está sendo descrito pela vez neste gênero. A identificação estrutural destes compostos foi feita com base na análise dos dados espectrais (IV, EM e RMN, incluindo DEPT e HMQC), bem como pela comparação com dados descritos na literatura.

This work describes the isolation of a pentacyclic triterpene (simiarenol), described for the first time in this family, two phytosteroids (sitostenone and sitosterol), a diterpene (trans-phytol) and a benzenoid (vanillic acid), described for the first time in this genus, from leaves and stem of Coccoloba mollis. These compounds were identified on basis of their spectral data (IR, MS and NMR, including DEPT and HMQC), as well as by comparison with literature data.

Terpenóides e avaliação do potencial antimalárico, larvicida, anti-radicalar e anticolinesterásico de Pouteria venosa (Sapotaceae) / Terpenoids and evaluation of the antimalarial, larvicidal, anti-radicalar and anticholinesterase potential of Pouteria venosa (Sapotaceae)

O presente trabalho descreve o isolamento de quatro triterpenos (taraxerol, ácido ursólico, ácido 3b,19a,23-triidroxiurs-12-en-28-óico e ácido 2a,3a,19a,23-tetraidroxiurs-12-en-28-óico) e um fitoesteróide (espinasterol), bem como a avaliação do potencial antimalárico (cepa NK-65 do Plasmodium berghei), larvicida (larvas do 4º instar do Aedes aegypti), anti-radicalar (2,2-difenil-1-picril-hidrazila, DPPH) e anticolinesterásico de extratos das folhas, cascas do caule e caule de Pouteria venosa (Mart.) Baehni. Todos os compostos isolados estão sendo descritos pela primeira vez nesta espécie e foram identificados com base na análise de dados espectrais (IV e RMN, incluindo APT e DEPT), bem como pela comparação com dados descritos na literatura.

This work describes the isolation of four triterpenes (taraxerol, ursolic acid, 3b,19a,23-trihydroxyurs-12-en-28-oic acid and 2a,3a,19a,23-tetrahydroxyurs-12-en-28-oic acid) and a phytosteroid (spinasterol), as well as a preliminary evaluation of antimalarial (NK-65 strains of Plasmodium berghei), larvicidal (4th instar of Aedes aegypti), anti-radicalar (2,2-diphenyl-1-pycryl-hydrazyl, DPPH) and anticholinesterase activities of Pouteria venosa (Mart.) Baehni extracts from leaves, stem barks and stems. All isolated compounds are being described for the first time in this species and were identified on basis of the spectral data (IR and NMR, including APT, DEPT), as well as by comparison with literature data.

Constituintes químicos das folhas e caule de Croton sellowii (Euphorbiaceae) / Chemical constituents from the leaves and stems of Croton sellowii (Euphorbiaceae)

O presente trabalho descreve o isolamento de terpenóides (sitosterol, estigmasterol, cicloart-25-eno-3b,24b-diol, cicloart-25-eno-3b,24a-diol e ácido betulônico), flavonóides (artemetina, crisosplenetina, casticina, penduletina e tilirosídeo) e fenilpropanóide (treo-7-etoxi-8-hidroxi-diidroanol) nas folhas e caule de Croton sellowii Baill. Todos os compostos isolados estão sendo descritos pela primeira vez nesta espécie e foram identificados com base na análise de dados espectrais (IV, UV e RMN, incluindo APT, DEPT, COSY, NOESY, HMQC e HMBC), bem como pela comparação com dados descritos na literatura.

This work describes the isolation of terpenoids (sitosterol, stigmasterol, cycloart-25-ene-3b,24b-diol, cycloart-25-ene-3b,24a-diol and betulonic acid), flavonoids (artemetin, crysosplenetin, casticin, penduletin and tiliroside) and phenylpropanoid (threo-7-ethoxy-8-hydroxy-dihydroanol) from the leaves and stems of Croton sellowii Baill. All isolated compounds are being described for the first time in this species and were identified on basis of the spectral data (IR, UV, and NMR, including APT, DEPT, COSY, NOESY, HMQC and HMBC), and by comparison with literature data.

Constituintes químicos e avaliação preliminar in vivo da atividade antimalárica de Ouratea nitida Aubl (Ochnaceae) / Chemical constituents and in vivo preliminary evaluation of antimalarial activity of Ouratea nitida Aubl. (Ochnaceae)

O presente trabalho descreve o isolamento de triterpenos (ácido 3,4-seco-friedelan-3-óico, friedelina e b-amirina) e outros compostos (éster etílico do ácido p-hidroxibenzóico e tetracosano), bem como a avaliação preliminar in vivo da atividade antimalárica de extratos das folhas de Ouratea nitida Aubl. Análise qualitativa através de CG-EM de uma fração apolar do extrato em hexano também foi efetuada. Ésteres metílicos e etílicos dos ácidos laúrico, mirístico, palmítico, esteárico e oléico, metílicos dos ácidos pentadecanóico, heptadecanóico, araquidônico, behênico e lignocérico e o etílico do ácido linoléico foram os componentes majoritários; enquanto que o estearato de n-butila, o tetracosano e a 6,10,14-trimetil-2-pentadecanona foram os minoritários. Os compostos isolados foram identificados com base na análise dos dados espectrais (IV, EM e RMN, incluindo DEPT) e estão sendo descritos pela primeira vez nesta espécie.

This work describes the isolation of triterpenes (3,4-seco-friedelan-3-oic acid, friedelin, and b-amyrin) and other compounds (p-hydroxybenzoic acid ethyl ester and tetracosane) as well as a preliminary evaluation of in vivo antimalarial activity of the extracts from the leaves of Ouratea nitida Aubl. Qualitative analysis by GC-MS of an apolar fraction from the hexane extract was also carried out. Methyl and ethyl esters of lauric, myristic, palmitic, stearic and oleic acids, methyl ester of pentadecanoic, heptadecanoic, arachidonic, beenic and lignoceric acids, and ethyl ester of linoleic acid were found to be the main constituents while n-butyl stearate, tetracosane and 6,10,14-trimetthyl-2-pentadecanone were the minor. All isolated compounds were identified on basis of the spectral data (IR, MS and NMR, including DEPT) and are being described for the first time in this specie.