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1.
Pharmaceuticals (Basel) ; 16(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37895859

RESUMO

The number of databases of natural products (NPs) has increased substantially. Latin America is extraordinarily rich in biodiversity, enabling the identification of novel NPs, which has encouraged both the development of databases and the implementation of those that are being created or are under development. In a collective effort from several Latin American countries, herein we introduce the first version of the Latin American Natural Products Database (LANaPDB), a public compound collection that gathers the chemical information of NPs contained in diverse databases from this geographical region. The current version of LANaPDB unifies the information from six countries and contains 12,959 chemical structures. The structural classification showed that the most abundant compounds are the terpenoids (63.2%), phenylpropanoids (18%) and alkaloids (11.8%). From the analysis of the distribution of properties of pharmaceutical interest, it was observed that many LANaPDB compounds satisfy some drug-like rules of thumb for physicochemical properties. The concept of the chemical multiverse was employed to generate multiple chemical spaces from two different fingerprints and two dimensionality reduction techniques. Comparing LANaPDB with FDA-approved drugs and the major open-access repository of NPs, COCONUT, it was concluded that the chemical space covered by LANaPDB completely overlaps with COCONUT and, in some regions, with FDA-approved drugs. LANaPDB will be updated, adding more compounds from each database, plus the addition of databases from other Latin American countries.

2.
Rev. bras. farmacogn ; 27(6): 785-787, Nov.-Dec. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-1042255

RESUMO

ABSTRACT Chemical investigation of the leaves of Casearia gossypiosperma Briq., Salicaceae, led to the isolation of two known flavonoids, (+)-taxifolin and quercetin, the leaves of Casearia decandra Jacq. have afforded hydroquinone, the leaves of Casearia rupestris Eichler and Casearia lasiophylla Eichler have afforded a diterpene, (E)-phytol, and the leaves of C. rupestris and Casearia obliqua Spreng. have afforded sitosterol. The twigs of Casearia lasiophylla Eichler led to the isolation of two compounds (+)-pinoresinol, and N-trans-feruloyltyramine, and the twigs of C. obliqua have afforded N-trans-feruloyltyramine, N-trans-cumaroyltyramine, and cinamic acid. This is the first report of the compounds (+)-taxifolin, quercetin, hydroquinone, (+)-pinoresinol and N-trans-cumaroyltyramine from the Casearia genus.

3.
J Nat Prod ; 80(5): 1674-1678, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28425292

RESUMO

Three new isoaigialones, A, B, and C (1-3), along with aigialone (4), were isolated from the crude EtOAc extract of a Phaeoacremonium sp., an endophytic fungus obtained from the leaves of Senna spectabilis. The structures of these compounds were elucidated based on the analysis of spectroscopic data. Compounds 2 and 4 were active against the phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum. This is the first report of metabolites produced by an Phaeoacremonium sp., associated with S. spectabilis.


Assuntos
Acetais/isolamento & purificação , Acetais/farmacologia , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Ascomicetos/química , Cladosporium/química , Cetonas/isolamento & purificação , Cetonas/farmacologia , Lactonas/isolamento & purificação , Folhas de Planta/química , Senna/química , Acetais/química , Antifúngicos/química , Cetonas/química , Lactonas/química , Lactonas/metabolismo , Lactonas/farmacologia , Estrutura Molecular
4.
J Nat Prod ; 79(3): 470-6, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26900954

RESUMO

Bioactivity-guided fractionation of the EtOH extract of the branches of Kielmeyera variabilis led to the isolation of a new acylphoroglucinol (1), which was active against all the MRSA strains tested herein, with pronounced activity against strain EMRSA-16. Compound 1 displayed an MIC of 0.5 mg/L as compared with an MIC of 128 mg/L for the control antibiotic norfloxacin. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, and experimental and calculated ECD were used to determine the absolute configurations. The compounds ß-sitosterol (2), stigmasterol (3), ergost-5-en-3-ol (4), and osajaxanthone (5) also occurred in the n-hexane fraction. The EtOAc fraction contained nine known xanthones: 3,6-dihydroxy-1,4,8-trimethoxyxanthone (6), 3,5-dihydroxy-4-methoxyxanthone (7), 3,4-dihydroxy-6,8-dimethoxyxanthone (8), 3,4-dihydroxy-2-methoxyxanthone (9), 5-hydroxy-1,3-dimethoxyxanthone (10), 4-hydroxy-2,3-dimethoxyxanthone (11), kielcorin (12), 3-hydroxy-2-methoxyxanthone (13), and 2-hydroxy-1-methoxyxanthone (14), which showed moderate to low activity against the tested MRSA strains.


Assuntos
Antibacterianos , Clusiaceae/química , Floroglucinol , Staphylococcus aureus/efeitos dos fármacos , Xantonas , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Brasil , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Componentes Aéreos da Planta/química , Estereoisomerismo , Xantonas/química , Xantonas/isolamento & purificação , Xantonas/farmacologia
5.
J Nat Prod ; 74(4): 776-81, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21381705

RESUMO

Four new clerodane diterpenes, casearupestrins A-D (1-4), were isolated from the leaves of Casearia rupestris. Compounds 1 and 4 were acetylated to yield 2,7-di-O-acetylcasearupestrin A (5) and 2,6-di-O-acetylcasearupestrin D (6). All compounds were evaluated for cytotoxicity against a small panel of human cancer cell lines. Casearupestrin A (1) exhibited the most potent activity against MDA/MB-435 (human melanoma) and SF-295 (human glioblastoma) cells, superior to that of the standard drug doxorubicin.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Casearia/química , Diterpenos Clerodânicos/isolamento & purificação , Diterpenos Clerodânicos/farmacologia , Antineoplásicos Fitogênicos/química , Brasil , Diterpenos Clerodânicos/química , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Folhas de Planta/química
6.
J Nat Prod ; 74(3): 487-91, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21341711

RESUMO

A lignan with a new skeleton named chimarrhinin (1) was isolated from an extract of the leaves of Chimarrhis turbinata, a Rubiaceae plant species. (13)C NMR spectrometric techniques including 1D and 2D experiments and HRESIMS provided unequivocal structural confirmation of this new C(6).C(3) skeleton type. The relative configuration of 1 was established by 2D (1)H-H analysis and J couplings, while its conformation was evaluated through molecular modeling using the RM1 semiempirical method, with the aid of coupling constants obtained by NMR analysis. The antioxidant activity of the new derivative 1 and two known and previously isolated phenolic derivatives (2 and 3) was investigated. An IC(50) value of 7.50 ± 0.5 µmol L(-1) was obtained for the new derivative 1, while 2 and 3 showed IC(50) values of 18.60 ± 0.4 and 18.50 ± 0.6 µmol, respectively.


Assuntos
Antioxidantes/isolamento & purificação , Lignanas/isolamento & purificação , Rubiaceae/química , Antioxidantes/química , Antioxidantes/farmacologia , Brasil , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química
7.
Nat Prod Res ; 25(1): 1-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21240754

RESUMO

A phytochemical investigation of the leaves and stems of Peperomia obtusifolia (Piperaceae) yielded a new flavone C-diglycoside isoswertisin-4'-methyl-ether-2''α-L-rhamnoside (1), along with four known compounds: isoswertisin-2''α-L-rhamnoside (2), (+)-diayangambin (3), 2-episesalatin (4) and corchoionoside C (5). The structures of the two flavone C-diglycosides (1, 2) were elucidated on the basis of 1D and 2D NMR spectroscopy and MS spectrometric data. These flavones were evaluated by bioautographic assay against Cladosporium cladosporioides and C. sphaerospermum and showed weak antifungal activity.


Assuntos
Antifúngicos/isolamento & purificação , Flavonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Peperomia/química , Folhas de Planta/química , Caules de Planta/química , Antifúngicos/química , Antifúngicos/farmacocinética , Cladosporium/efeitos dos fármacos , Flavonas/química , Flavonas/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
9.
Rev. bras. farmacogn ; 19(1a): 61-67, Jan.-Mar. 2009. ilus, graf
Artigo em Português | LILACS | ID: lil-522423

RESUMO

Pterogyne nitens (Fabaceae-Caesalpinioideae) é uma árvore nativa da América do Sul, onde é empregada na medicina popular para o tratamento da ascaridíase. Recentemente, descrevemos o efeito mutagênico do extrato etanólico das folhas de P. nitens. Dessa forma, o presente estudo teve por objetivo aprofundar a avaliação do potencial mutagênico das frações isoladas das folhas de Pterogyne nitens, acetato de etila (AcOEt), n-butanólica (BuOH) e hidroalcóolica (HA). Quando o efeito mutagênico foi observado somente nas maiores concentrações testadas, o potencial antimutagênico também foi avaliado. Os ensaios mutagênicos e antimutagênicos foram realizados utilizando ensaio de micronúcleo em Trandescantia pallida. Na avaliação de mutagenicidade, observou-se o efeito nas frações AcOEt (0,460 mg/mL), BuOH (0,142, 0,285, 0,570 e 1,14 mg/mL) e HA (0,050, 0,100, 0,200 e 0,400 mg/mL). Considerando que o efeito mutagênico da fração AcOEt foi observado somente na concentração mais elevada (0,460 mg/mL), o potencial antimutagênico da mesma foi avaliado. As concentrações de 0,115 e 0,230 mg/mL da fração AcOEt demonstraram atividade antimutagênica. A partir dos resultados do presente estudo, conclui-se que determinadas frações de P. nitens apresentam mutagenicidade (BuOH e HA), enquanto a fração AcOEt apresentou efeito antimutagênico nas maiores concentrações. Esses resultados tornam o estudo da P. nitens bastante promissor, considerando que esta planta possui distribuição geográfica ampla e tem sido pouco estudada.


Pterogyne nitens (Fabaceae-Caesalpinioideae) is a tree native to South American, where it is used in folk treatment of ascaridiasis. Recently, we have been describing the mutagenic effect of the ethanol extract of leaves of P. nitens. Thus, the present study aimed at evaluating the mutagenic potential of the ethyl acetate (EtOAc), n- butanol (BuOH) and hydroalcoholic (HA) fractions. When the mutagenic effect was observed only in the highest tested concentrations, the antimutagenic activity was also evaluated. Both mutagenic and antimutagenic assays were performed using T. pallida micronuclei assay. Mutagenicity was observed between different concentrations of the P nitens fractions, EtOAc (0.460 mg/mL), BuOH (0.142, 0.285, 0.570 and 1.14 mg/mL) and HA (0.050, 0.100, 0.200 and 0.400 mg/mL). Whereas the mutagenic effect of the EtOAc fraction was observed in the highest concentration (0.460 mg/mL), its antimutagenic potential was evaluated. The 0.115 and 0.230 mg/mL concentrations of the EtOAc fraction demonstrated antimutagenic activity. Based on the results of the present study we can conclude that some P. nitens fractions (BuOH and HA) demonstrated mutagenic effects whereas the EtOAc fraction shown low mutagenicity and amtimutagenicity in the two higher concentrations. Those results stimulate the studies with P. nitens, which possess spread geographic distribution and it is still low studied.

10.
Phytochemistry ; 68(15): 2053-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17574633

RESUMO

The biosynthesis of (2S)-2-methyl-2-(4'-methyl-3'-pentenyl)-8-(3''-methyl-2-butenyl)-2H-1-benzopyran-6-carboxylic acid (gaudichaudianic acid), the major metabolite in leaves and roots of Piper gaudichaudianum Kunth (Piperaceae), has been investigated employing [1-(13)C]-D-glucose as precursor. The labelling pattern in the isolated gaudichaudianic acid was determined by quantitative (13)C NMR spectroscopy analysis and was consistent with involvement of both mevalonic acid and 2-C-methyl-D-erythritol-4-phosphate pathways in the formation of the dimethylallyl- and geranyl-derived moieties. The results confirmed that both plastidic and cytoplasmic pathways are able to provide isopentenyl diphosphate units for prenylation of p-hydroxybenzoic acid.


Assuntos
Benzoatos/metabolismo , Piper/metabolismo , Terpenos/metabolismo , Benzoatos/isolamento & purificação , Eritritol/análogos & derivados , Eritritol/metabolismo , Glucose/metabolismo , Hemiterpenos/metabolismo , Ácido Mevalônico/metabolismo , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos Organofosforados/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Fosfatos Açúcares/metabolismo , Terpenos/isolamento & purificação
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