Flavonóides e triterpenos de Baccharis pseudotenuifolia: bioatividade sobre Artemia salina

The phytochemical investigation of the chloroformic and methanolic extracts of the Baccharis pseudotenuifolia led to the isolation of triterpenes, steroids and flavonoids. From chloroformic extract were isolated oleanolic acid and alpha-spinasterol while from methanolic extract were isolated the flavonoids: hispidulin, naringenin, 3'-methoxy-luteolin, apigenin, kaempferol, eriodyctiol, aromadendrin, quercetin, 3'-methoxy-quercetin, quercetin-3-O-rhamnoside and quercetin-3-O-glucoside. The structure of these compounds were identified by IR, CG/MS, ¹H and 13C NMR spectral analysis and comparison with literature. In addition, the extracts were evaluated by means of Brine Shrimp Lethality test and the highier activity was observed in the chloroformic extract.

Flavonóide e triterpenos de Stigmaphyllom paralias

Stigmaphyllom paralias is a herb belonging to the family Malpighiaceae that occurs in sand soil of brazilian " restinga". This is the first report regarding phytochemical study with this species. The hexane extract of the aerial parts of plant afforded the triterpenes friedelin, lupenone, 3-oxo-alpha-amirin and 3-oxo-beta-amirin, the mixture of alpha-amirinyl palmitate and stearate, lupeol and 3,4-seco-friedelan-3-oic acid. The AcOEt extract yielded the flavonoid luteolin-7-rutinoside. All compounds were characterized by analysis of spectrometric data and the fatty acids esterified with alpha-amirine were identified by GC/MS of methyl derivatives of transesterified products . This is the first natural occurence of 3,4-seco-friedelan-3-oic acid and the 13C NMR spectral data were inequivocally assigned by two-dimensional techniques. This work also permitted to correct the 13C NMR resonances attributed to methyl groups C-26 and C-27 of fridelin.

Novel santalane sesquiterpenoids from the stem bark of Duguetia glabriuscula - Annonaceae

Five novel santalane-type sesquiterpenes were isolated from the stem bark of Duguetia glabriuscula - Annonaceae. Their structures have been established on the basis of spectral data and chemical evidences (¹H and 13C NMR, HMQC, HMBC) as (+)-alpha-santal-10-en-9-ol (1), (+)-alpha-santalan-10,11-epoxy-9-ol (2), alpha-santal-11-en-9,10-diol (3), (+)-alpha-santalan-9,10,11-triol (4), and (+)-alpha-santalan-9,11-epoxy-10-ol (5). Polycarpol, a triterpenoid, was also obtained.

Determinação de compostos de massa molecular alta em folhas de plantas da Amazônia

The fractIons of dichloromethane extracts of leaves from andiroba (Carapa guianensis - Meliaceae), caapi (Banisteriopsis caapi - Malpighiaceae), cocoa (Theobroma cacao - Sterculiaceae), Brazil nut (Bertholletia excelsa - Lecytidaceae), cupuaçu (Theobroma grandiflorum - Sterculiaceae), marupá (Simaruba amara - Simaroubaceae) and rubber tree (Hevea brasiliensis - Euphorbiaceae), were analyzed by HT-HRGC and HT-HRGC-MS. Esters of homologous series of fatty acids and long chain alcohols, phytol, amyrines and tocopherols were characterized. The characterization of the compounds was based mainly in mass spectra data and in addition by usual spectrometric data (¹H and 13C NMR, IR).

Lignanas de Strychnos guianensis (Aublet) Mart.

The present communication reports the isolation and identification of three lignans from metanolic root extracts of Strychnos guianensis (Aublet) Mart.: olivil (1), cycloolivil (2) and the unknown derivative cycloolivil carbonate (3). From hexane extracts was identified a long chain fatty acid mixture and the triterpene lupeol. The analyses were based on chromatographic and spectroscopy techniques (IR, MS, GC/MS, ¹H-NMR and 13C-NMR, 1D (BB, DEPT 135) and 2D (¹H, ¹ H-COSY, ¹H, 13C-COSY, ¹H, 13C-COSY-LR, HMQC, HMBC and NOESY) and comparison with literature data.

Estudo químico e perfil cromatográfico das cascas de Aspidosperma parvifolium A. DC. ("pau-pereira")

Four known alkaloids, uleine, epiuleine, apparicine and desmethyluleine, besides the isoprenoids lupeol and stigmasterol were isolated from the stem bark of Aspidosperma parvifolium. Their identification was based on spectroscopic analysis (UV, IR, ¹H-NMR, 13C-NMR, MS). The chromatographic profile of the ethanolic extract was obtained by HPLC and uleine, epiuleine and apparicine were identified in the extract.

Triterpenóides tipo cicloartano de própolis de Teresina - PI

The chemical study of the propolis produced in Teresina city, state of Piaui, resulted in the identification of six cycloartane triterpenoids: isomangiferolic acid, 24-methylenecycloartane-3beta,26-diol, mangiferolic acid, mangiferonic acid, ambonic acid and ambolic acid. The substances were characterized by one and two-dimensional ¹H and 13C NMR analysis.

Triterpenóides pentacíclicos das folhas de Terminalia brasiliensis

Eleven oleanane, ursane and lupane-type triterpenes were isolated from the leaves of Terminalia brasiliensis Camb, daturadiol (3b,6beta-dihydroxy-olean-12-ene), 3beta-hydroxy-30-norlupan-20-one, lupenone, beta-amyrenone, alpha-amyrenone, lupeol, beta-amyrin, alpha-amyrin, betulin, erythrodiol and uvaol, in addition to squalene, sitosterol and alpha-tocopherol. The structures of these compounds were identified by ¹H and 13C NMR spectral analysis and comparison with literature data.

Constituintes químicos de Bombacopsis glabra (bombacaceae)

The chemical study of the barks of the stem and roots of Bombacopsis glabra (Bombacaceae) led to the isolation and identification of 5-hydroxy-3,7,4'-trimethoxyflavone (1), 5-hydroxy-3,6,7,4'-tetramethoxyflavone (2), the naphtoquinone isohemigossypolone (3), the ester triacontil p-coumarate (4) besides lupeol and a mixture of beta-sitosterol and stigmasterol. Their structures were elucidated by spectroscopic analysis, including IR, ¹H and 13C NMR and MS. All these compounds, except 3, were isolated for the first time in the family.

Síntese de aliloxi-orto-iodobenzamida derivada de d-glicose e reação de ciclização radicalar mediada por hidreto de tri-n-butilestanho

Methyl 6-O-allyl-2,3-di-O-benzyl-4-deoxy-4-(2 -iodobenzoylamine)-alpha-D-glucopyranoside was synthesized in nine conventional steps from methyl alpha-D-glucopyranoside. Its Bu3SnH-mediated aryl radical cyclization provided a benzomacrolactam, resulting from 11-endo aryl radical cyclization and the reduced uncyclized product methyl 6-O-allyl-4-benzoylamine-2,3-di-O-benzyl-4-deoxy- alpha-D-glucopyranoside. The structures of the three new products were supported by ¹H and 13C NMR spectroscopy and DEPT, COSY and HMQC experiments.

Preparative separation of flavonoids from the medicinal plant Davilla elliptica St. Hill. by high-speed counter-current chromatography

High-speed counter-current chromatography (HSCCC) is a major tool for the fast separation of natural products from plants. It was used for the preparative isolation of the flavonoid monoglucosides present in the aerial parts of the Davilla elliptica St. Hill. (Dilleniaceae). This species is used in Brazilian folk medicine for the treatment of gastric disorders. The optimum solvent system used was composed of a mixture of ethyl acetate-n-propanol-water (140:8:80, v/v/v) and led to a successful separation of quercetin-3-O-alpha-L-rhamnopyranoside and myricetin-3-O-alpha-L-rhamnopyranoside in approximately 3.0 hours with purity higher than 95%. Identification was performed by ¹H NMR, 13C NMR and HPLC-UV-DAD analyses.

Constituintes químicos da casca do caule de Amburana cearensis A.C. Smith

The phytochemical analysis of the ethanol extract trunk bark of Amburana cearensis allowed the isolation and identification of twelve constituents: coumarin, sucrose, two phenol acids (vanillic acid and protocatechuic acid), five flavonoids (afrormosin, isokaempferide, kaempferol, quercetin and 4'-methoxy-fisetin), a phenol glucoside (amburoside A) and a mixture of glucosilated b-sitosterol and stigmasterol. Their structures were elucidated by spectroscopic methods such as IR, MS, ¹H and 13C NMR, including uni and bidimensional techniques, in addition to comparison with literature data.

Síntese e caracterização de um novo complexo de platina (IV) a partir de seu análogo de platina (II) utilizando iodo molecular como agente oxidante: uma rota sintética interessante para obtenção de novos complexos de platina

In an attempt to reduce toxicity and widen the spectrum of activity of cisplatin and its analogues, much attention has been focused on designing new platinum complexes. This work reports the synthesis and characterization of novel compounds of the platinum (II) and platinum (IV) containing 2-furoic hydrazide acid and iodide as ligands. Although the prepared compounds do not present the classical structure of biologically active platinum analogues, they could be potentially active or useful as precursors to prepare antitumor platinum complexes. The reported compounds were characterized by ¹H NMR, 13C NMR, 195Pt NMR, IR and elemental analyses.

Alcalóides aporfinóides do gênero Ocotea (Lauraceae)

During the last decades several aporphinoid alkaloids of the Ocotea species have been isolated. This review describes the occurrence of the fifty four aporphinoids in seventeen different species of Ocotea: thirty nine (39) aporphine sensu stricto, four (4) oxoaporphine, five (5) 6a,7-dehydroaporphine, one (1) didehydroaporphine, one (1) C-3-O-aporphine, one (1) C-4-O-aporphine, two (2) phenanthrene, one (1) proaporphine and their 13C NMR spectral data.

Chemical constituents from Bakeridesia pickelii Monteiro (Malvaceae) and the relaxant activity of kaempferol-3-O-beta-D-(6"-E-p -coumaroyl) glucopyranoside on guinea-pig ileum

The phytochemical investigation of Bakeridesia pickelii Monteiro led to the isolation of seven compounds: beta-sitosterol, a mixture of sitosteryl-3-O-beta-D-glucopyranoside and stigmasteryl-3-O-beta-D-glucopyranoside, vanillic acid, p-coumaric acid, quercetin 3-O-beta-D-glucopyranoside (isoquercitrin) and kaempferol-3-O-beta-D-(6"-E-p -coumaroyl) glucopyranoside (tiliroside), which was isolated as the major component. Their structures were elucidated on the basis of spectroscopic data such as IR, ¹H and 13C NMR, including two-dimensional techniques. Tiliroside relaxed the guinea-pig ileum pre-contracted with KCl 40 mM (EC50 = 9.5 ± 1.0 x 10-5 M), acetylcholine 10-6 M (EC50 = 2.3 ± 0.9 x 10-5 M) or histamine 10-6 M (EC50 = 4.1 ± 1.0 x 10-5 M) in a concentration-dependent manner.