The Zika virus is a flavivirus spread by the Aedes aegypti mosquito, which also transmits dengue and chikungunya. Current forms of control include elimination of mosquito breeding sites, use of insecticides, repellents and other means. The present study developed new adsorbent materials based on silica and biomaterials capable of releasing an Aedes aegypti mosquito repellent. The materials synthesized were characterized by Fourier-Transform Infrared, thermogravimetric analysis, Scanning Electron Microscopy and Brunauer, Emmett and Teller analysis and tested with citronella, an essential oil widely recognized as a natural insect repellent. The materials presented type IV isotherms, with type H1 hysteresis, characteristic of mesoporous materials, with pore diameters of between 50 Å and 80 Å. Materials based on silica-chitosan-glutaraldehyde dried in an oven (SCGO) and silica-chitosan-glutaraldehyde dried under a vacuum (SCGV) were found to produce more controlled release of citronella essential oil. The bioassay test was performed using a horizontal double-choice olfactometer. The adsorbent SCGO remained stable for the four hours of the bioassay, while the commercial repellent became ineffective after two hours of release. The production of a prototype in the form of bracelets, stickers releasing a volatile repellent is therefore proposed as a method for the control of the mosquito in urban areas.

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.

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.

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.

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.

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.

Dois novos diterpenos do tipo clerodano, crotobrasilina A e crotobrasilina B, foram isolados juntamente com quatro 3-metoxiflavonas conhecidas: casticina, penduletina, crisosplenol-D e artemetina, das folhas e caule de Croton brasiliensis. A elucidação estrutural destes compostos foi feita com base na análise dos dados espectroscópicos, especialmente RMN, incluindo técnicas bidimensionais (COSY, HMQC, HMBC e NOESY).

Two new clerodane diterpenes, crotobrasilin A and crotobrasilin B, were isolated in addition to four known 3-methoxyflavones: casticin, penduletin, chrysosplenol-D and artemetin from leaves and stems of Croton brasiliensis. The structural elucidation of these compounds was made on the basis of spectroscopic data analyses, especially NMR, including 2D techniques (COSY, HMQC, HMBC and NOESY).