Avaliação da atividade antioxidante, fotoprotetora e antiglicação dos extratos de folhas e frutos de espécies da família Annonaceae

Pós-graduação em Biociências - FCLAS

Antifungals and acetylcholinesterase inhibitors from the stem bark of Croton heliotropiifolius

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Coumarins from Brosimum gaudichaudii

The new coumarin, (+)-(2'S,3'R)-3-hydroxymarmesin [1], was isolated from the aqueous fraction of the EtOH extract of the root bark of Brosimum gaudichaudii (Moraceae).

Cycloartane derivatives from Guarea trichilioides

Investigation of the leaves of Guarea trichilioides afforded nine cycloartane derivatives including the following seven novel ones: cycloart-24-en-. © 1993.

Lignans and diterpenes of three Aristolochia species

Phytochemical examination of Aristolochia cymbifera, A. esperanzae and A. galeata led to the isolation of furofuran and dibenzylbutyrolactone type lignans, as well as of clerodane and ent-labdane type diterpenes. Structural assignments for two new ent-labdans are presented and discussed. © 1988.

Terpenes from Aristolochia triangularis

Phytochemical examination of Aristolochia triangularis led to the isolation of allantoin, nerolidol, sitosterol, dibenzylbutyrolactone type lignans and ent-kaurane type diterpenes. This is the first report on the isolation of ent-kaurane from a natural source. © 1990.

8-benzylberbine alkaloids from Aristolochia gigantea

Phytochemical examination of Aristolochia gigantea led to the isolation of 10 alkaloids, belonging to the new 8-benzylberbine type. Eight of them occurred as glucosides. The structural assignments were based on analysis of physical and spectral data. © 1992.

Neolignans from fruits of Virola elongata

Fruits of Virola elongata contain, besides the furofuranoid lignans eudesmin, epieudesmin and fargesin, the aryl-benzyl-methyl tetrahydrofuran neolignans magnostellins A and C. The absolute configuration of the magnostellins was detennined.

Phytochemical characterization, antimicrobial activity, and antioxidant potential of Equisetum hyemale L. (Equisetaceae) extracts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caffeic acid esters and triterpenes of Alibertia macrophylla

A hydroalcoholic extract of the leaves of Alibertia macrophylla afforded the esters of caffeic acid and 2-phenylethanol or 2-methyl butane-1,4-diol. The leaves also contain caffeic acid. The acetone extract of the stems of A. macrophylla contain α-amyrin, β-amyrin, α-amyrenone, β-amyrenone, lupeol, lupenone and germanicone. Structural assignments were taken through spectral data analysis and physical properties. This is the first report on the chemistry of Alibertia. © 1991.

Fungitoxic non-glycosidic iridoids from Alibertia macrophylla

The aqueous alcohol extract of the leaves of Alibertia macrophylla afforded two epimeric pairs of iridoid aglycones and one of them showed high inhibitory activity against Aspergillus niger, Cladosporium sphaerospermum, C. cladosporioides and Colletotrichum gloesporioides. Three of the compounds are reported for the first time from natural sources. Their structures were established on the basis of spectroscopic studies, mainly through 13C NMR analysis. © 1992.

Benzylisoquinoline alkaloids and eudesmane sesquiterpenes from Ocotea pulchella

Bark of Ocotea pulchella contains, besides 1-(p-methoxybenzoyl)-6,7-methylenedioxyisoquinoline, 1-(hydroxy-p-methoxybenzyl)-6,7-methylenedioxyisoquinoline and their 1,2-dihydro-derivatives, 11-eudesmen-4α-ol and 4-furanoeudesmen-6-one. © 1993.

Neolignans from Aniba citrifolia

The trunk wood of Aniba citrifolia contains hydrobenzofuranoid and bicyclo[3.2.1]octanoid neolignans. © 1984.

Hexahydrobenzofuranoid neolignans from an Aniba species

The trunk wood of an Amazonian Aniba species contains three novel neolignans: (2R, 3R, 3aS, 5R)-3a-allyl-5-methoxy-2-(3,4,5-trimethoxyphenyl)-3-methyl-2,3,3a,4,5,6-hexahydro-6-oxobenzofuran (canellin-D), (2R,3R,3aS,5R)-3a-allyl-5,7-dimethoxy-2-(3-methoxy-4,5-methylenedioxyphenyl)-3-methyl-2,3,3a,4,5,6-hexahydro-6-oxobenzofuran (canellin-E) and (2S,3S,3aS,5R)-3a-allyl-5-methoxy-2-(3-methoxy-4,5-methylenedioxyphenyl)-3-methyl-2,3,3a,4,5,6-hexahydro-6-oxobenzofuran (armenin-C). The absolute stereochemistries of these and of all other known hexahydro-6-oxobenzofurans were determined by CD comparisons with model compounds. © 1984.

Gama-Lactones from Iryanthera species

The structure of juruenolide, a constituent of Iryanthera juruensis and I. ulei is revised to (2S, 3R, 4S)-3-hydroxy-4-methyl-2-(19′-piperonyl-1′-n-nonadecyl)-butanolide. The compound is epimeric at C-3 of the γ-lactone unit with grandinolide [(2S, 3S, 4S)-3-hydroxy-4-methyl-2- (19′-phenyl-1′-n-nonadecyl)-butanolide] from I. grandis. An extract of I. juruensis contained additionally juruenolide-B [(4S)-4-methyl-2-(19′-piperonyl-1′-n-nonadec-7′-enyl)-but-2-enolide]. Analogous products with heptadecyl and pentadecyl side chains co-occur with the respective nonadecyl derivatives. © 1983.