Jane Eire Silva Alencar de Menezes

Óleos essenciais das folhas de Vernonia Remotiflora e Vernonia Brasiliana: composição química e atividade biológica

The chemical composition of the essential oils, obtained by hidrodistillation, from leaves of two Vernonia species (V. remotiflora and V. brasiliana), was determined by GC-FID and GC-MS. Both essential oils were predominantly constituted by sesquiterpenes (92.0 - 93.4%). The main constituents of the oil from V. brasilana were (E)-caryophyllene (36.7%), germacrene D (35.5%), and α-humulene (11.7%), while (E)-caryophyllene (42.2%) and bicyclogermacrene (20.0%) were the major ones in the oil from V. remotiflora. Although with moderate activity both oils showed acetylcholinesterase and antibacterial activities.

Trichotomol, a New Cadinenediol from Cordia trichotoma

Um novo sesquiterpeno, nomeado trichotomol e compostos conhecidos como cordiacromo C, a-cadinol, acido oleanolico, oncocalyxona A, b-sitosterol, glicosideo do b-sitosterol, alantoina e sacarose foram isolados a partir do extrato etanolico do cerne de Cordia trichotoma. Suas estruturas foram determinadas por analises espectroscopicas e comparacao com dados publicados para compostos estruturalmente relacionados.

Essential Oil of Croton cajucara Benth

Abstract The chemical composition of aerial parts of Croton cajucara were analyzed by GC/MS. Twenty-two components were identified, oil with the main components being linalool (13.5%), γ-muuorolene (18.4%) and (Z)-sesquilavandulol (12.6%).

Chemical Composition and Larvicidal Activity of the Essential Oil From Leaves of Cordia globosa (Jacq.) H.B.K. from Northeastern Brazil

Abstract The chemical composition of the essential oils obtained from the fresh leaves of Cordia globosa (Jacq.) H.B.K., at different ontogenetic stages, were analyzed by GC and GC/MS. Twenty-three and 26 volatile constituents were identifed for the oils at the fowering and fructifcation stages, respectively. In both oils, the main compounds were bicyclogermacrene (22.7%-13.1%) and β-caryophyllene (11.9%-11.6%).

Sesquiterpenes and a Phenylpropanoid from Cordia trichotoma

Two new secondary metabolites, the phenylpropanoid 3-(2′,4′,5′-trimethoxyphenyl)propanoic acid (1) and the sesquiterpene (+)-1β,4β,6α-trihydroxyeudesmane (2) were isolated from the heartwood of Cordia trichotoma Vell., along with the known sesquiterpenes (D)-1β,4β,7α- trihydroxyeudesmane (3) and (+)-1β,4β,11-trihydroxyoppositane (4). Their structures were elucidated by means of spectroscopic data interpretation, mainly 1D and 2D NMR and mass spectrometry.

Composição química volátil e não-volátil de Eupatorium ballotifolium Kunth, Asteraceae

This work describes the chemical composition of the essential oils and the isolation of eleven substances from Eupatorium ballotifolium Kunth, Asteraceae. The essential oils were obtained by hydrodistillation, analyzed by GC/MS and evaluated towards the acetylcholinesterase enzyme. The oils yield was of 0.11% for the leaves and 0.03% for the stems. The main constituents of the oils were the sesquiterpenes β-caryophyllene (24.9 and 22.2%), spathulenol (17.7 and 12.4%) and epoxy-allo-aromadendrene (23.0 and 23.6%). From the hexane extract of the aerial part were isolated a mixture of sitosterol and stigmasterol, its glucosides, and the triterpenes taraxasteryl acetate and taraxasterol, while from the ethanol extract were obtained the flavonoids nepetin and 3-O-glucoside-quercetin. The triterpenes epi-friedelanol and dammara-20,24-dien-3β-ol were obtained from the hexane extract of roots, while the coumarin 11-hydroxy-11,12-di-hydroobliquine was obtained from the ethanol extract. The structures of all compounds were determinate based on spectroscopic methods such as IR, MS and 1H and 13C NMR