Licanol, um novo flavanol, e outros constituintes de Licania macrophylla Benth

The phytochemical investigation of L. macrophylla Benth led to the isolation of a new flavanol named licanol: (-)-4'-O-methyl-epigallocatechin-3'-O-α-L-rhamnoside, along with nine known compounds, identified as: (-)-4'-O-methyl-epigallocatechin, pheophytin A, 13²-hydroxy-(13²-S)-pheophytin A, pheophytin B, sitosterol, stigmasterol, sitosterol-β-O-glucoside, betulinic alcohol and oleanolic acid. The structures were established based on IR, HR-ESI-MS, and NMR spectrometric data analysis with the aid of 2D techniques. The methanolic extracts of leaves and stem bark as well as the compounds licanol, 13²-hidroxi-(13²-S)-feofitina A, and betulinic alcohol demonstrated antimicrobial activity against several bacterial strains.

Constituintes químicos das folhas de Riedeliella graciliflora Harms (Leguminosae)

A new salicylic acid derivative, pentacosanyl salicylate, was isolated from the leaves of the plant toxic to cattle, Riedeliella graciliflora, in addition to a digalactosyldiacylglycerol (DGDG), 1,2-di-O-α-linolenoyl-3-O-α-D-galactopyranosyl-(1→6)-β-D-galactopyranosyl-glycerol, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-α-L-rhamnopyranoside, quercetin-3-O-α-L-rhamnopyranoside, rutin, (+)-catechin and the dimer (+)-catechin-(4β-8)-catechin, glutinol, squalene, β-sitosterol, stigmasterol, phytol, β-carotene, α-tocopherol and ficaprenol-12. Their structures were determined using spectral techniques (MS, IR, and NMR-1D and 2D) and based on literature data.

Constituintes químicos dos galhos de Simaba guianensis subesp. ecaudata (Cronquist)

Simaba guianensis subesp. ecaudata (Simaroubaceae) is a tree found in the Brazilian Amazon. This work describes for the first time the fractionation of stems of this species that resulted in the isolation of the cytotoxic triterpene piscidinol A, the alkaloid 9-methoxycanthin-6-one, caryophyllene oxide, also isolated for the first time from this species and a new alkaloid (6-methoxy-(9H-β-carbolin-1-il)-(Z)-2-propenoic acid). Quantification of 9-methoxycanthin-6-one in different extracts and fractions of stems of S. guianensis by high performance liquid chromatography was also performed. The concentration of 9-methoxycanthin-6-one in methanolic and aqueous extracts were inferior to the known cytotoxic concentration of this compound.

Constituintes químicos de Capraria biflora (Scrophulariaceae) e atividade larvicida de seu óleo essencial

Analysis of essential oil from fresh leaves of Capraria biflora allowed identification of fourteen essential oil constituents among which thirteen are sesquiterpene compounds, and α-humulene (43.0%) the major constituent. The essential oil was tested for larvicidal activity against Aedes aegypti showing good activity, with LC50 73.39 µg/mL (2.27 g/mL). Chromatographic studies of extracts from roots and stems allowed the isolation of five compounds: naphthoquinone biflorin, sesquiterpene caprariolide B, the steroid β-sitosterol, the carbohydrate D-mannitol and iridoid myopochlorin first reported in the species C. biflora. The structures of compounds were characterized by spectroscopic data, IR, MS, NMR13C, NMR¹H, NOE, HSQC and HMBC.

Pregnanos e outros constituintes das raízes de Macrosiphonia petraea (A. St.-Hil.) Kuntze (Apocynaceae)

Macrosiphonia petraea (A. St.-Hil.) Kuntze is a plant popularly known as "velame". Its root infusion is used in the folk medicine of Mato Grosso do Sul, Brazil, for the treatment of inflammatory diseases. Phytochemical investigation of the roots of this species led to the identification of 17 compounds belonging to four different classes: two pregnanes, 12β-hydroxypregna-4,6,16-triene-3,20-dione, neridienone A, and 12β-hydroxypregna-4,6-diene-3,20-dione, cybisterol, one hydroxylated fatty acid, 5-hydroxy-octadeca-6(E)-8(Z)dienoic acid, two lignoids, pinoresinol and 8a-hydroxypinoresinol, ten pentacyclic triterpenoids, and two steroids.

Constituintes químicos e atividade antioxidante de Byrsonima gardneriana (Malpighiaceae)

The phytochemical investigation of Byrsonima gardneriana led to the isolation of five triterpenes and one flavonoid: D:B-Friedoolean-5-en-3-one (1), friedoolean-14-en-3-one (2), friedelan-3-one (3), lup-20(29)-en-3-ol (4), 3β-hydroxiolean-12-ene (5) and 3,3',4',5,7-pentahydroxyflavan (6). Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques and comparison with published spectral data. Antioxidant activities of ethanol extract and phases were measured using the 1,2-diphenyl- 2-picryl-hydrazyl (DPPH) free radical scavenging assay, evaluation of total phenolic content and trolox equivalent antioxidant capacity (TEAC).

Constituintes químicos de Vernonia scorpioides (Lam) Pers. (Asteraceae)

The chemical investigation of hexane and ethanol extracts from the aerial parts of Vernonia scorpioides resulted in the isolation and characterization of a new polyacetylene lactone, rel-4-dihydro-4β-hydroxy-5a-octa-2,4,6-triynyl-furan-2-(5H)-one, along with the new ethyl 3,4-dihydroxy-6,8,10-triynyl-dodecanoate, and seven known compounds: taraxasteryl acetate, lupeyl acetate, lupeol, lupenone, β-sitosterol, stigmasterol and luteolin. The structure of all compounds was determined by spectrometric techniques (HR-ESI-MS, ¹H and 13C NMR and IV) and comparison with published spectral data.

Constituintes fenólicos e atividade antioxidante da geoprópolis de duas espécies de abelhas sem ferrão amazônicas

We investigated the phenolic constituents and antioxidant activity of geopropolis from two species of stingless Amazonian bees, Melipona interrupta and Melipona seminigra. The chemical investigation of geopropolis from Melipona interrupta led to the isolation of 5,7,4'-trihydroxyflavonone, 3,5,6,7,4'-pentahydroxyflavonol, naringenine-4'-O-b-D-glucopyranoside and myricetin-3-O-b-D-glucopyranoside. Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques. Antioxidant activity of methanol and ethanol extracts of M. interrupta and M. seminigra were measured using the 1,2-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay. This is also the first work reporting the chemical investigation of stingless bee species from the Amazonian region.

Constituintes químicos de Solanum buddleifolium Sendtn

The chemical investigation of the stem EtOH extract of S. buddleifolium resulted in the isolation of terpenoids, amides, lignans and a steroidal alkaloid. Based on HRMS, IR and ¹H and 13C NMR data analysis, the structures of the isolated compounds were identified as: 13-hydroxysolavetivone, betulinic acid, N-trans-caffeoyltyramine, N-trans-feruloyldopamine, N-trans-p-cumaroyltyramine, N-trans-feruloyltyramine, N-trans-feruloyl3'-O-methoxydopamine, alangilignoside C, isolariciresinol, polistachiol, (+)-(8R,7'S,8'S)-3α-O-(β-D-glucopiranosyl)-lioniresinol, (-)-(8S,7'R,8'R)-3α-O-(β-D-glucopiranosyl)-lioniresinol and solamargine. The occurrence of terpenoids and amides is common in Solanum, unlike lignans which are rare. The isolated lignans described in this work are reported for the first time in the genus Solanum.

Constituintes químicos e avaliação da atividade antibacteriana de Macroptilium lathyroides (L.) Urb. (Fabaceae)

The chemical investigation of the stems and branches of Macroptilium lathyroides led to the isolation of a mixture of β-sitosterol and stigmasterol. The extracts from the roots allowed the isolation of lasiodiplodin, a mixture of stigmast-4-en-6β-ol-3-one and stigmast-4,22-dien-6β-ol-3-one, de-O-methyllasiodiplodin, genistein and lupinalbin A. The structures of the isolated compounds were assigned on the basis of their NMR data, including comparison of their spectral data with values described in the literature. The antibacterial activity of crude extracts from stems, branches and roots was evaluated. This is the first report involving the chemical investigation of this species.

Constituintes químicos das cascas do caule de Vochysia thyrsoidea Pohl. (Vochysiaceae) e avaliação das atividades citotóxica e inibitória frente as catepsinas B e K

A new flavonoid, catechin-3-O-(3"-O-trans-cinnamoyl)-α-rhamnopyranoside, along with known compounds, catechin-3-O-α-rhamnopyranoside, 3-oxo-urs-12-en-28-oic acid, 2,4,6-trimethoxybenzoic acid, 2-butyl-D-fructofuranoside and 1-butyl-D-fructofuranoside, has been isolated from the stem bark of V. thyrsoidea. These compounds were assayed for inhibition of protease activity (cathepsins B and K) and against cancer cell lines. Catechin-3-O-(3"-O-trans-cinnamoyl)-α-rhamnopyranoside showed moderate inhibitory activity (IC50 = 62.02 µM) against cathepsin B while 2-butyl-D-fructofuranoside was the most potent against a strain of CNS (SF-295) and human leukemia (HL-60) with IC50 = 36.80 µM and IC50 = 25.37 µM, respectively.

Sesquiterpenos e outros constituintes das folhas de Pterodon pubescens Benth (Leguminosae)

In addition to β-sitosterol, stigmasterol, phaeophitin A, luteolin, kaempferol, quercetin, (+)-catechin, quercetin-3-O-α-L-rhamnopyranoside, rutin, and p-hydroxy-benzoic acid, six known sesquiterpenes, namely (rel)-2β,6β-epoxy-5β-hydroxy-isodaucane, oplopanone, 1β,6α-dihydroxy-4(15)-eudesmene, caryophyllene oxide, α-cadinol, and spathulenol, were isolated from the leaves of Pterodon pubescens (Leguminosae) growing in the Cerrado of Mato Grosso do Sul, Brazil. The (rel)-2β,6β-epoxy-5β-hydroxy-isodaucane corresponds to the correct structure of homalomenol D. The sesquiterpene oplopanone, which bears a modified cadinane skeleton, is being reported for the first time in this genus. The structures of the compounds were determined on the basis of spectral data (MS, IR, and NMR-1D and 2D) and subsequent comparison with data reported in the literature.

Constituintes químicos e atividade antioxidante de folhas e galhos de Eugenia copacabanensis Kiaersk (Myrtaceae)

Phytochemical investigation of Eugenia copacabanensis allowed for the isolation and identification of following compounds: β-sitosterol, β-sitosterol-glucoside, eight triterpenes, (mixture of α- and β-amyrins, ursolic acid, 30-hydroxy-ursolic acid, betulin, friedelin, friedelan-3,4-lactone, and taraxerol), a mixture of three sesquiterpenes, (clovandiol, globulol, and viridiflorol), three flavonoids (kaempferol-3-O-β-D-rhamnoside, quercetin-3-O-α-L-arabinoside, and quercetin), and a mixture of four coumaroyl esters (octacosanyl, heptacosanyl, hexacosanyl, and tetracosanyl coumarates). The structures of these compounds were assigned based on comparison with literature data and spectroscopic analysis, including analysis by two-dimensional NMR techniques. Total phenolic content and total flavonoids were evaluated. Antioxidant activities of methanol extracts and fractions were measured by the 1,2-diphenyl-2-picryl-hidrazyl free radical scavenging assay.

Constituintes químicos e avaliação das atividades antioxidante e anti-inflamatória das raízes de Sabicea brasiliensis wernh (Rubiaceae)

The phytochemical investigation of Sabicea brasiliensis roots led to the isolation of 5-O-caffeoylquinic acid, 3,5- and 4,5-O-dicaffeoylquinics acids, scopoletin, ursolic acid, a mixture of β-sitosterol, stigmasterol and campesterol, daucosterol and saccharose. The structures of the isolated compounds were assigned on the basis of one- and two-dimensional NMR spectroscopic methods and by comparison with literature data. The anti-inflammatory and antioxidant activities of the crude methanolic extract and its fractions were analyzed.