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1.
Elife ; 112022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35616633

RESUMO

Contemporary bioinformatic and chemoinformatic capabilities hold promise to reshape knowledge management, analysis and interpretation of data in natural products research. Currently, reliance on a disparate set of non-standardized, insular, and specialized databases presents a series of challenges for data access, both within the discipline and for integration and interoperability between related fields. The fundamental elements of exchange are referenced structure-organism pairs that establish relationships between distinct molecular structures and the living organisms from which they were identified. Consolidating and sharing such information via an open platform has strong transformative potential for natural products research and beyond. This is the ultimate goal of the newly established LOTUS initiative, which has now completed the first steps toward the harmonization, curation, validation and open dissemination of 750,000+ referenced structure-organism pairs. LOTUS data is hosted on Wikidata and regularly mirrored on https://lotus.naturalproducts.net. Data sharing within the Wikidata framework broadens data access and interoperability, opening new possibilities for community curation and evolving publication models. Furthermore, embedding LOTUS data into the vast Wikidata knowledge graph will facilitate new biological and chemical insights. The LOTUS initiative represents an important advancement in the design and deployment of a comprehensive and collaborative natural products knowledge base.


Assuntos
Produtos Biológicos , Gestão do Conhecimento , Biologia Computacional , Bases de Dados Factuais , Conhecimento
2.
Front Nutr ; 8: 762753, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926546

RESUMO

Flavonoids are a vast group of metabolites that are essential for vascular plant physiology and, thus, occur ubiquitously in plant-based/-derived foods. The solitary designation of thousands of known flavonoids hides the fact that their metabolomes are structurally highly diverse, consist of disparate subgroups, yet undergo a certain degree of metabolic interconversion. Unsurprisingly, flavonoids have been an important theme in nutrition research. Already in the 1930s, it was discovered that the ability of synthetic Vitamin C to treat scurvy was inferior to that of plant extracts containing Vitamin C. Subsequent experimental evidence led to the proposal of Vitamin P (permeability) as an essential phytochemical nutrient. However, attempts to isolate and characterize Vitamin P gave confusing and sometimes irreproducible results, which today can be interpreted as rooted in the unrecognized (residual) complexity of the intervention materials. Over the years, primarily flavonoids (and some coumarins) were known as having Vitamin P-like activity. More recently, in a NAPRALERT meta-analysis, essentially all of these Vitamin P candidates were identified as IMPs (Invalid/Improbable/Interfering Metabolic Panaceas). While the historic inability to define a single compound and specific mode of action led to general skepticism about the Vitamin P proposition for "bioflavonoids," the more logical conclusion is that several abundant and metabolically labile plant constituents fill this essential role in human nutrition at the interface of vitamins, cofactors, and micronutrients. Reviewing 100+ years of the multilingual Vitamin P and C literature provides the rationales for this conclusion and new perspectives for future research.

3.
J Med Chem ; 63(21): 12137-12155, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32804502

RESUMO

This Perspective of the published essential medicinal chemistry of cannabidiol (CBD) provides evidence that the popularization of CBD-fortified or CBD-labeled health products and CBD-associated health claims lacks a rigorous scientific foundation. CBD's reputation as a cure-all puts it in the same class as other "natural" panaceas, where valid ethnobotanicals are reduced to single, purportedly active ingredients. Such reductionist approaches oversimplify useful, chemically complex mixtures in an attempt to rationalize the commercial utility of natural compounds and exploit the "natural" label. Literature evidence associates CBD with certain semiubiquitous, broadly screened, primarily plant-based substances of undocumented purity that interfere with bioassays and have a low likelihood of becoming therapeutic agents. Widespread health challenges and pandemic crises such as SARS-CoV-2 create circumstances under which scientists must be particularly vigilant about healing claims that lack solid foundational data. Herein, we offer a critical review of the published medicinal chemistry properties of CBD, as well as precise definitions of CBD-containing substances and products, distilled to reveal the essential factors that impact its development as a therapeutic agent.


Assuntos
Canabidiol/farmacologia , Animais , Canabidiol/farmacocinética , Canabidiol/uso terapêutico , Canabidiol/toxicidade , Química Farmacêutica , Ensaios Clínicos como Assunto , Humanos , Efeito Placebo
4.
J Nat Prod ; 83(6): 1950-1959, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32463230

RESUMO

NMR- and MS-guided metabolomic mining for new phytoconstituents from a widely used dietary supplement, Rhodiola rosea, yielded two new (+)-myrtenol glycosides, 1 and 2, and two new cuminol glycosides, 3 and 4, along with three known analogues, 5-7. The structures of the new compounds were determined by extensive spectroscopic data analysis. Quantum mechanics-driven 1H iterative full spin analysis (QM-HiFSA) decoded the spatial arrangement of the methyl groups in 1 and 2, as well as other features not recognizable by conventional methods, including higher order spin-coupling effects. Expanding applied HiFSA methodology to monoterpene glycosides advances the toolbox for stereochemical assignments, facilitates their structural dereplication, and provides a more definitive reference point for future phytochemical and biological studies of R. rosea as a resilience botanical. Application of a new NMR data analysis software package, CT, for QM-based iteration of NMR spectra is also discussed.


Assuntos
Monoterpenos/química , Rhodiola/química , Glicosídeos/química , Hidrólise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Teoria Quântica
5.
Fitoterapia ; 129: 401-414, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29175549

RESUMO

This article reviews and develops a perspective for the meaning of authenticity in the context of quality assessment of botanical materials and the challenges associated with discerning adulterations vs. contaminations vs. impurities. Authentic botanicals are by definition non-adulterated, a mutually exclusive relationship that is confirmed through the application of a multilayered set of analytical methods designed to validate the (chemo)taxonomic identity of a botanical and certify that it is devoid of any adulteration. In practice, the ever-increasing sophistication in the process of intentional adulteration, as well as the growing number of botanicals entering the market, altogether necessitate a constant adaptation and reinforcement of authentication methods with new approaches, especially new technologies. This article summarizes the set of analytical methods - classical and contemporary - that can be employed in the authentication of botanicals. Particular emphasis is placed on the application of untargeted metabolomics and chemometrics. An NMR-based untargeted metabolomic model is proposed as a rapid, systematic, and complementary screening for the discrimination of authentic vs. potentially adulterated botanicals. Such analytical model can help advance the evaluation of botanical integrity in natural product research.


Assuntos
Contaminação de Medicamentos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/normas , Fitoterapia/normas , Produtos Biológicos/análise , Produtos Biológicos/normas , Espectroscopia de Ressonância Magnética , Metabolômica , Controle de Qualidade
6.
PhytoKeys ; (75): 81-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28127246

RESUMO

Brunfelsia cabiesesiana J. G. Graham, sp. nov. (Solanaceae), a new species from montane cloud forests of Ucayali and Pasco Departments, Peru, is described and illustrated. The new species differs from all other members of the genus Brunfelsia by its cauline inflorescences. A key to the Peruvian species of Brunfelsia is presented.


Resumen Brunfelsia cabiesesiana J. G. Graham, sp. nov. (Solanaceae), descrita e ilustrada aquí, constituye una nueva especie de los bosques nublados de los departamentos de Ucayali y Pasco, Perú. La nueva especie difiere de todas las demás especies de Brunfelsia por sus inflorescencias caulinas. Se presenta aquí también una clave para las especies peruanas de Brunfelsia.

7.
J Ethnopharmacol ; 151(2): 903-11, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24333958

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: There is widespread use of traditional herbal remedies in the Lao PDR (Laos). It is common practice to treat many diseases with local plants. This research project documented and analysed some of these traditional remedies used to treat symptoms of tuberculosis (TB). MATERIALS AND METHODS: This research was executed by interviewing healers about plants used traditionally to treat the symptoms of TB. Samples of some of the plants were collected, and extracts of 77 species were submitted to various in vitro assays in order to determine the amount of growth inhibition of virulent Mycobacterium tuberculosis H37Rv (Mtb), as opposed to other microbes and mammalian Vero cells. RESULTS: Interviews took place with 58 contemporary healers in 5 different provinces about plants currently used, giving a list of 341 plants. Bioassay-guided fractionation was performed on Marsypopetalum modestum (Pierre) B. Xue and R.M.K. Saunders (Annonaceae), leading to the isolation of dipyrithione, an anti-mycobacterial compound isolated for the first time from the genus Marsypopetalum through this research. CONCLUSIONS: This research has helped to increase awareness of Laos' rich diversity of medicinal plants and will hopefully provide incentive to preserve the undeveloped forested areas that remain, which still hold a wealth of medical information for future discoveries.


Assuntos
Annonaceae , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Chlorocebus aethiops , Coleta de Dados , Feminino , Humanos , Laos , Masculino , Medicinas Tradicionais Africanas , Mycobacterium tuberculosis/crescimento & desenvolvimento , Fitoterapia , Tuberculose/tratamento farmacológico , Células Vero
8.
Am J Clin Nutr ; 87(2): 504S-8S, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18258647

RESUMO

The University of Illinois at Chicago/National Institutes of Health Center for Botanical Dietary Supplements Research began in 1999 with an emphasis on botanical dietary supplements for women's health. We have concentrated on plants that may improve women's health, especially to reduce hot flashes in menopausal women, alleviate the symptoms of premenstrual syndrome, and reduce persistent urinary tract infections. The primary focus of this article is to describe the operation of our center, from acquiring and identifying botanicals to isolating and identifying active constituents, to elucidating their mechanisms of action, and to conducting phase I and phase II clinical studies. Black cohosh (Actaea racemosa; syn Cimicifuga racemosa) has been used as a model to illustrate the steps involved in taking this plant from the field to clinical trials. Bioassays are described that were necessary to elucidate the pertinent biological studies of plant extracts and their mechanisms of action. We conclude that this type of research can only be successful with the use of a multidisciplinary approach.


Assuntos
Bioensaio , Pesquisa Biomédica/organização & administração , Cimicifuga , Suplementos Nutricionais , Fitoterapia , Preparações de Plantas/uso terapêutico , Saúde da Mulher , Ensaios Clínicos como Assunto , Feminino , Fogachos/tratamento farmacológico , Humanos , Illinois , National Institutes of Health (U.S.) , Preparações de Plantas/farmacologia , Síndrome Pré-Menstrual/tratamento farmacológico , Estados Unidos , Universidades , Infecções Urinárias/tratamento farmacológico
9.
Planta Med ; 71(8): 792-4, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16142652

RESUMO

A phytochemical investigation of the CHCl (3)-soluble extract of the entire plant of Egletes viscosa (Asteraceae), collected in Peru, afforded two new labdane glycosides, 13-hydroxy-7-oxolabda-8,14-diene 13( R)- O-alpha- L-arabinopyranoside and 13-hydroxylabda-7,14-diene 13( R)- O-alpha- L-arabinopyranoside, along with four known compounds. The structures of the new compounds were elucidated by spectroscopic and chemical methods.


Assuntos
Asteraceae , Fitoterapia , Extratos Vegetais/química , Diterpenos/química , Glicosídeos/química , Humanos , Espectroscopia de Ressonância Magnética , Componentes Aéreos da Planta
10.
Arch Pharm Res ; 27(2): 169-72, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15022717

RESUMO

Activity-guided fractionation of the EtOAc-soluble extract of the stems of Couepia ulei, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells led to the isolation of two active compounds, a new natural product, erythro-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-1-ol (1), and a known compound, evofolin-B (2), along with five inactive compounds all of known structure, viz., betulinic acid, oleanolic acid, pomolic acid, (+/-)-syringaresinol, and ursolic acid. These isolates were identified by analysis of physical and spectral data. Compounds 1 and 2 exhibited QR inducing activity, with observed CD (concentration required to double induction) values of 16.7 and 16.4 microM, respectively.


Assuntos
NAD(P)H Desidrogenase (Quinona)/biossíntese , Fenóis/isolamento & purificação , Fenóis/farmacologia , Rosaceae/química , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Fenômenos Químicos , Físico-Química , Cromatografia em Camada Fina , Indução Enzimática/efeitos dos fármacos , Camundongos , Extratos Vegetais/farmacologia , Caules de Planta/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Nat Prod ; 67(3): 352-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15043409

RESUMO

Cytotoxicity-based, bioassay-guided fractionation of the chloroform-soluble extracts of both the roots and leaves of Picramnia latifolia led to the isolation of two new anthrone C-glycosides, picramniosides G (1) and H (2), two new oxanthrone C-glycosides, mayosides D (3) and E (4), and a new benzanthrone natural product, 6,8-dihydroxy-10-methyl-7H-benz[de]anthracen-7-one (5), together with 10 known compounds, 6,8-dihydroxy-4-methyl-7H-benz[de]anthracen-7-one (6), nataloe-emodin (7), chrysophanein, chrysophanol, 1,5-dihydroxy-7-methoxy-3-methylanthraquinone, pulmatin, 7-hydroxycoumarin, 7-hydroxy-6-methoxycoumarin, beta-sitosterol, and beta-sitosterol glucoside. The structures of 1-5 were established by spectroscopic methods, including 1D and 2D NMR, HRMS, and CD data interpretation. The cytotoxic activity of all isolates was evaluated in a small panel of human cancer cell lines. Compound 7 exhibited significant in vitro cytotoxic activity in the tested cell lines, but no significant activity was observed with an in vivo hollow fiber model at doses of 6.25, 12.5, 25, and 50 mg/kg/injection.


Assuntos
Antracenos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Glicosídeos/isolamento & purificação , Plantas Medicinais/química , Antracenos/química , Antracenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peru , Folhas de Planta/química , Estereoisomerismo , Células Tumorais Cultivadas
12.
J Nat Prod ; 67(2): 225-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14987063

RESUMO

Bioactivity-directed fractionation of the methanolic extract of the stem and fruits of Senna obliqua led to the isolation of two known antimycobacterial natural products, quinquangulin (1) and rubrofusarin (2). Both compounds had minimum inhibitory concentrations (MICs) of 12.0 microg/mL against Mycobacteriatuberculosis in radiometric culture. This is the first report of antimycobacterial activity associated with naphthopyrone compounds. Their structures were determined by spectroscopic means including 1D and 2D NMR techniques and further confirmed by X-ray crystallographic analysis.


Assuntos
Antituberculosos/isolamento & purificação , Naftóis/isolamento & purificação , Plantas Medicinais/química , Pironas/isolamento & purificação , Senna/química , Antituberculosos/química , Antituberculosos/farmacologia , Cristalografia por Raios X , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Naftóis/química , Naftóis/farmacologia , Peru , Pironas/química , Pironas/farmacologia
13.
Arch Pharm Res ; 26(8): 585-90, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12967190

RESUMO

Activity-guided fractionation of the EtOAc-soluble extract of the whole plants of Sida acuta using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells, led to the isolation of ten active compounds of previously known structure, quindolinone (1), cryptolepinone (2), 11-methoxyquindoline (3), N-trans-feruloyltyramine (4), vomifoliol (5), loliolide (6), 4-ketopinoresinol (7), scopoletin (8), evofolin-A (9), and evofolin-B (10), along with five inactive compounds of known structure, ferulic acid, sinapic acid, syringic acid, (+/-)-syringaresinol, and vanillic acid. These isolates were identified by physical and spectral data measurement. A new derivative of quindolinone, 5,10-dimethylquindolin-11-one (1a) was synthesized and characterized spectroscopically. Of the active substances, compounds 1-3 and 1a exhibited the most potent QR activity, with observed CD (concentration required to double induction) values ranging from 0.01 to 0.12 microg/mL. Six compounds were then evaluated in a mouse mammary organ culture assay, with cryptolepinone (2), N-trans-feruloyltyramine (4), and 5,10-dimethylquindolin-11-one (1a) found to exhibit 83.3, 75.0, and 66.7% inhibition of 7,12-dimethylbenz[a]anthracene-induced preneoplastic lesions, respectively, at a dose of 10 microg/mL.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Transformação Celular Neoplásica/efeitos dos fármacos , Malvaceae/química , Glândulas Mamárias Animais/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/biossíntese , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Alternativas ao Uso de Animais , Animais , Antineoplásicos Fitogênicos/química , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/induzido quimicamente , Indução Enzimática/efeitos dos fármacos , Glândulas Mamárias Animais/citologia , Camundongos , Estrutura Molecular , Técnicas de Cultura de Órgãos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
J Nat Prod ; 66(9): 1166-70, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14510590

RESUMO

A new butenylflavanone, (2S)-5-hydroxy-7-methoxy-8-[(E)-3-oxo-1-butenyl]flavanone (1), and a new rotenoid, 4',5'-dihydro-11,5'-dihydroxy-4'-methoxytephrosin (2), as well as three active flavonoids of previously known structure, isoliquiritigenin (3), genistein (4), and chrysoeriol (5), along with nine known inactive compounds, alpha-toxicarol (6), sumatrol, 6a,12a-dehydro-alpha-toxicarol, 11-hydroxytephrosin, obovatin, marmesin, lupenone, benzyl benzoate, and benzyl trans-cinnamate, were isolated from an ethyl acetate-soluble extract of the stems of Tephrosia toxicaria, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. All isolates were evaluated for their potential cancer chemopreventive properties utilizing an in vitro assay to determine quinone reductase induction. Selected compounds were tested in a mouse mammary organ culture assay to evaluate the inhibition of 7,12-dimethylbenz[a]anthracene (DMBA)-induced preneoplastic lesions.


Assuntos
Anticarcinógenos/isolamento & purificação , Cromonas/isolamento & purificação , Flavonoides/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Plantas Medicinais/química , Tephrosia/química , Animais , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Carcinoma Hepatocelular , Cromonas/química , Cromonas/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Neoplasias Mamárias Experimentais , Camundongos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Peru , Caules de Planta/química , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
15.
J Nat Prod ; 66(8): 1089-93, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12932130

RESUMO

Two new C-18 norwithanolides based on a C(27) skeleton, subtrifloralactones K (1) and L (2), a new C-18 oxygenated withanolide, 13 beta-hydroxymethylsubtrifloralactone E (3), and a new alpha-ionone derivative, (+)-7 alpha,8 alpha-epoxyblumenol B (4), along with five known compounds, philadelphicalactone A (5), (2S,3S,4R)-2-[(2R)-2'-hydroxytetracosanoylamino]-1,3,4-octadecanetriol (6), trans-N-feruloyltyramine, cis-N-feruloyltyramine, and (S)-coriolic acid, were isolated from additional active fractions of the chloroform-soluble extract of Deprea subtriflora, using a quinone reductase (QR) induction assay as a monitor. The structures of compounds 1-4 were characterized by spectroscopic data interpretation. The potential cancer chemopreventive activities of all isolates in terms of their ability to induce QR activity with cultured Hepa 1c1c7 mouse hepatoma cells were evaluated.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Lactonas/isolamento & purificação , Solanaceae/química , Solanaceae/metabolismo , Animais , Carcinoma Hepatocelular , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Lactonas/química , Lactonas/farmacologia , Camundongos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona) , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Células Tumorais Cultivadas
16.
Phytochemistry ; 63(3): 335-41, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12737982

RESUMO

Activity-guided fractionation of an EtOAc-soluble extract of the leaves of Muntingia calabura collected in Peru, using an in vitro quinone reductase induction assay with cultured Hepa 1c1c7 (mouse hepatoma) cells, resulted in the isolation of a flavanone with an unsubstituted B-ring, (2R,3R)-7-methoxy-3,5,8-trihydroxyflavanone (5), as well as 24 known compounds, which were mainly flavanones and flavones. The structure including absolute stereochemistry of compound 5 was determined by spectroscopic (HRMS, 1D and 2D NMR, and CD spectra) methods. Of the isolates obtained, in addition to 5, (2S)-5-hydroxy-7-methoxyflavanone, 2',4'-dihydroxychalcone, 4,2',4'-trihydroxychalcone, 7-hydroxyisoflavone and 7,3',4'-trimethoxyisoflavone were found to induce quinone reductase activity.


Assuntos
Flavonoides/isolamento & purificação , Flavonoides/farmacologia , NAD(P)H Desidrogenase (Quinona)/biossíntese , Plantas Medicinais/química , Animais , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Indução Enzimática/efeitos dos fármacos , Flavonoides/química , Neoplasias Hepáticas Experimentais , Camundongos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Células Tumorais Cultivadas
17.
J Nat Prod ; 66(5): 583-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12762787

RESUMO

A new cassane diterpene, dipteryxic acid (1), and a new isoflavonolignan, 5-methoxyxanthocercin A (2), as well as four known active compounds, isoliquiritigenin (3), 6,4'-dihydroxy-3'-methoxyaurone (4), sulfuretin (5), and (+/-)-balanophonin (6), and five known inactive compounds, butin, eriodictyol, 7-hydroxychromone, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, and (-)-lariciresinol, were isolated from an ethyl acetate-soluble extract of the seeds of Dipteryx odorata, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structures of compounds 1 and 2 were elucidated by spectroscopic data interpretation. Single-crystal X-ray diffraction analysis was used to confirm the relative stereochemistry of compound 1. Selected compounds (3-5) were evaluated in a mouse mammary organ culture assay, with isoliquiritigenin (3) found to exhibit 76% inhibition at a dose of 10 microg/mL.


Assuntos
Anticarcinógenos/isolamento & purificação , Diterpenos/isolamento & purificação , Fabaceae/química , Isoflavonas/isolamento & purificação , Lignanas/isolamento & purificação , Animais , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Cristalografia por Raios X , Modelos Animais de Doenças , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Indução Enzimática , Concentração Inibidora 50 , Isoflavonas/química , Isoflavonas/farmacologia , Lignanas/química , Lignanas/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Camundongos , Conformação Molecular , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/biossíntese , Ressonância Magnética Nuclear Biomolecular , Técnicas de Cultura de Órgãos , Peru , Sementes/química , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
18.
J Org Chem ; 68(6): 2350-61, 2003 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-12636402

RESUMO

Activity-monitored fractionation of a CHCl(3)-soluble extract of Deprea subtriflora using a quinone reductase induction assay led to the purification of subtrifloralactones A-J (1-10), 10 novel C-18 norwithanolides based on a new C(27) skeleton. These compounds were characterized by spectroscopic and chemical studies, and single-crystal X-ray diffraction analysis was used to confirm the structures of 1 and 4. Compounds 1-10 were evaluated for their cancer chemopreventive activity in terms of their ability to induce quinone reductase activity with cultured murine hepatoma cells, and compounds 1 and 6 were found to be highly effective.


Assuntos
Lactonas/isolamento & purificação , Plantas Medicinais/química , Solanaceae/química , Animais , Anticarcinógenos , Carcinoma Hepatocelular , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Lactonas/química , Lactonas/farmacologia , Camundongos , Conformação Molecular , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Ressonância Magnética Nuclear Biomolecular , Peru , Células Tumorais Cultivadas/efeitos dos fármacos
19.
J Nat Prod ; 65(11): 1616-20, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12444686

RESUMO

Three new prenylated dihydrochalcones, (+/-)-nicolaioidesins A, B, and C (1-3), as well as a new natural product, 5-styrylfuran-2-carboxylic acid methyl ester (4), along with four known compounds, 2'-hydroxy-4',6'-dimethoxychalcone (5), (+/-)-5-hydroxy-7-methoxyflavanone (6), (+/-)-5-hydroxy-7,4'-dimethoxyflavanone, and panduratin A, were isolated from the roots of Renealmia nicolaioides, using a bioassay to determine the induction of quinone reductase (QR) activity with cultured Hepa lclc7 mouse hepatoma cells. Among these isolates, 5 and 6 induced QR activity, with observed concentrations to double activity (CD) values of 1.7 and 0.9 microg/mL, respectively, while the other constituents were not regarded as being active (CD >10 microg/mL). The chemical structures of 1-4 were elucidated by spectroscopic methods. A biogenetic pathway for the formation of (+/-)-nicolaioidins A-C (1-3) is proposed.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Chalcona/isolamento & purificação , Plantas Medicinais/química , Zingiberaceae/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular , Chalcona/análogos & derivados , Chalcona/química , Chalcona/farmacologia , Chalconas , Cromatografia Líquida de Alta Pressão , Ensaios de Seleção de Medicamentos Antitumorais , Concentração Inibidora 50 , Camundongos , Conformação Molecular , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Peru , Raízes de Plantas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas/efeitos dos fármacos
20.
J Agric Food Chem ; 50(22): 6330-4, 2002 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-12381112

RESUMO

A new bicyclic diarylheptanoid, rel-(3S,4aR,10bR)-8-hydroxy-3-(4-hydroxyphenyl)-9-methoxy-4a,5,6,10b-tetrahydro-3H-naphtho[2,1-b]pyran (1), as well as four known compounds, 1,2-dihydro-1,2,3-trihydroxy-9-(4-methoxyphenyl)phenalene (2), hydroxyanigorufone (3), 2-(4-hydroxyphenyl)naphthalic anhydride (4), and 1,7-bis(4-hydroxyphenyl)hepta-4(E),6(E)-dien-3-one (5), were isolated from an ethyl acetate-soluble fraction of the methanol extract of the fruits of Musa x paradisiaca cultivar, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structure and relative stereochemistry of compound 1 were elucidated unambiguously by one- and two-dimensional NMR experiments ((1)H NMR, (13)C NMR, DEPT, COSY, HMQC, HMBC, and NOESY) and single-crystal X-ray diffraction analysis. Isolates 1-5 were evaluated for their potential cancer chemopreventive properties utilizing an in vitro assay to determine quinone reductase induction and a mouse mammary organ culture assay.


Assuntos
Neoplasias Mamárias Experimentais/enzimologia , Musa/química , NAD(P)H Desidrogenase (Quinona)/biossíntese , Extratos Vegetais/farmacologia , Animais , Carcinoma Hepatocelular/enzimologia , Indução Enzimática , Feminino , Neoplasias Hepáticas Experimentais/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Células Tumorais Cultivadas
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