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1.
Phytochemistry ; 173: 112301, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32092557

RESUMO

A phytochemical investigation of the root of Angelica dahurica led to the isolation of benzofuran and coumarin derivatives. This is the first report of the isolation and identification of three furanocoumarin sulfates from A. dahurica root. The structures of a total of twelve undescribed compounds were determined by extensive spectroscopic analysis, including 2D NMR data, hydrolysis, and solvolysis, followed by either physicochemical and spectroscopic data or X-ray crystallographic analysis. The isolated compounds were evaluated for their PPAR-γ ligand-binding activity, and six compounds showed significant PPAR-γ ligand-binding activity. In particular, the undescribed benzofuran derivative, 3-[6,7-furano-9-hydroxy-4-(2″,3″-dihydroxy-3″-methylbutyloxy)]-phenyl propionic acid, exhibited the most potent PPAR-γ ligand-binding activity and accumulated intracellular lipid in 3T3-L1 cells.


Assuntos
Angelica , Benzofuranos , Cumarínicos , PPAR gama , Raízes de Plantas
2.
Shokuhin Eiseigaku Zasshi ; 60(4): 96-107, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31474657

RESUMO

LC/Tribrid Orbitrap was developed to determine phosphodiesterase-5 (PDE-5) inhibitors and their analogs as adulterants in dietary supplements. High-resolution MS/MS and MS3 spectra of PDE-5 inhibitors and their analogs were obtained by LC/Tribrid Orbitrap using both higher-energy collisional dissociation and collision-induced dissociation. We investigated dietary supplements that claim to enhance men's sexual performance, and detected PDE-5 inhibitors and their analogs. We also estimated the structures of the PDE-5 inhibitor analogs and the impurities of PDE-5 inhibitors and their analogs in the dietary supplements.


Assuntos
Suplementos Nutricionais/análise , Inibidores da Fosfodiesterase 5/análise , Espectrometria de Massas em Tandem , Cromatografia Líquida , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5
3.
Angew Chem Int Ed Engl ; 58(26): 8839-8844, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31025431

RESUMO

1,1-Diamino-2,2-bis(triflyl)ethylenes with both twisted and planar structures around the partial "C=C" bond were synthesised. Bonding properties in these compounds were analysed by an experimental approach using high-resolution X-ray diffraction data treated with X-ray wavefunction refinement (XWR). In the twisted compound, a dominant contribution of the charge-separated resonance structure was revealed. On the contrary, the nearly planar compound still showed π-bonding character, however, with a considerable contribution of the charge-separated resonance structure.

4.
Chem Asian J ; 14(1): 205-215, 2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30393964

RESUMO

Two RA-series bicyclic hexapeptides, RA-XXV (4) and RA-XXVI (5), which have no N-methyl group at Tyr-5, were isolated from the roots of Rubia cordifolia L. Their amino acid compositions and sequences were determined by interpretation of MS, and 1D and 2D NMR data and their relative structures were elucidated by XRD analysis of 4 and RA-XXVI acetate (6). The absolute stereochemistry of 4 was established by the total synthesis of 4, and that of 5, by the chemical correlation with 4. Peptides 4 and 5 exhibited cytotoxicity toward human promyelocytic leukemia HL-60 (IC50 =0.062 and 0.066 µm, respectively) and human colonic carcinoma HCT-116 (IC50 =0.028 and 0.051 µm, respectively) cell lines. Analysis of the conformational structures of 4 and 6 in the crystalline state and those of 4 and 5 in solution revealed that the N-methyl group at Tyr-5 functions to make this series of peptides preferentially adopt the active conformation.


Assuntos
Antineoplásicos Fitogênicos/química , Peptídeos Cíclicos/química , Rubia/química , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Teoria da Densidade Funcional , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Células HL-60 , Humanos , Modelos Moleculares , Método de Monte Carlo , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/farmacologia , Conformação Proteica
5.
Molecules ; 24(1)2018 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-30585226

RESUMO

Phytochemical analysis of the tubers of Eranthis cilicica was performed as part of our continuous study on the plants of the family Ranunculaceae, which resulted in the isolation of eleven new cycloartane glycosides (1⁻11) and one new oleanane glycoside (13), together with one known oleanane glycoside (12). The structures of the new compounds were determined by extensive spectroscopic analysis, including two-dimensional (2D) NMR, and enzymatic hydrolysis followed by either X-ray crystallographic or chromatographic analysis. The aglycone (1a) of 2 and its C-23 epimer (8a), and the oleanane glycosides (12 and 13) showed cytotoxic activity against HL-60 leukemia cells with IC50 values ranging from 10.6 µM to 101.6 µM. HL-60 cells were much more sensitive to 8a (IC50 14.8 µM) than 1a (IC50 101.1 µM), indicating that the C-23 configuration is associated with the cytotoxicity of these cycloartane derivatives. Compound 12 was revealed so as to partially induce apoptotic cell death in HL-60 cells, as was evident from morphology of HL-60 cells treated with 12.


Assuntos
Glicosídeos/química , Ácido Oleanólico/análogos & derivados , Ranunculaceae/metabolismo , Triterpenos/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/farmacologia , Células HL-60 , Humanos , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Tubérculos/química
6.
J Pharm Biomed Anal ; 148: 136-141, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29017110

RESUMO

Two analogs of sildenafil (compounds 1 and 2) were detected in three powder products acquired from online drug markets during an LC-UV-MS analysis of psychotropic drugs. Their structures were established by high-resolution mass spectrometry and NMR spectroscopy. Compound 1 was identified as 5-(5-(3,5-dimethylpiperazine-1-carbonothioyl)-2-ethoxyphenyl)-1-methyl-3-propyl-1H-pyrazolo[4,3-d]pyrimidine-7(6H)-thione and named dimethyldithiodenafil. Compound 2 was identified as 5-(5-(3,5-dimethylpiperazine-1-carbonothioyl)-2-ethoxyphenyl)-1-methyl-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one and named dimethylthiocarbodenafil. Compound 1 was subjected to the phosphodiesterase assay (IC50=0.20nM). The three powder products were found to contain 12-19mg of dimethyldithiodenafil and 1.4-3.9mg of dimethylthiocarbodenafil per tube.


Assuntos
Inibidores de Fosfodiesterase/química , Citrato de Sildenafila/química , Cromatografia Líquida/métodos , Espectroscopia de Ressonância Magnética/instrumentação , Espectrometria de Massas/métodos , Pós/química , Psicotrópicos/química , Pirimidinas/química
7.
Chem Asian J ; 11(23): 3389-3397, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27863076

RESUMO

RA-dimer B, a new cytotoxic RA-series peptide, was isolated from the roots of Rubia cordifolia L. Its structure was elucidated on the basis of spectroscopic analysis to be a dimeric cyclopeptide composed of deoxybouvardin and allo-RA-V. Those two cyclopeptide units are connected by an ether linkage between the phenolic oxygen atom of deoxybouvardin and the ϵa carbon atom of Tyr-6 of allo-RA-V. RA-dimer B was synthesized by the coupling reaction of deoxybouvardin with the boronic acid derivative of allo-RA-V, and subsequent deprotection, confirming the relative stereochemistry and establishing the absolute configuration of this peptide. RA-dimer B showed cytotoxic activity against human promyelocytic leukaemia HL-60, human colonic carcinoma HCT-116, and human renal cell carcinoma ACHN cells with IC50 values of 0.59, 0.54, and 0.74 µm, respectively.


Assuntos
Peptídeos Cíclicos/química , Rubia/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Células HCT116 , Células HL-60 , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/toxicidade , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Rubia/química
8.
Org Lett ; 18(21): 5568-5571, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27740762

RESUMO

Efavirenz is manufactured worldwide, and its asymmetric synthesis requires a complex organometallic approach, while an organocatalytic approach is far less efficient. The first highly enantioselective approach is disclosed for the synthesis of Efavirenz under nonmetal organocatalysis with up to 93% ee for the Merck intermediate and 91% ee for the Lonsa intermediate using novel alkynyl cinchona catalysts.

9.
J Nat Prod ; 79(9): 2175-80, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27598828

RESUMO

Three new sesquiterpenoids-vetiverianines A (1), B (2), and C (3)-and a known eudesmane sesquiterpenoid (4) were isolated from the roots of Vetiveria zizanioides. Vetiverianine A (1) has a unique carbon framework comprising a rigid tricyclic ring system. Vetiverianines B (2) and C (3) are new eremophilane sesquiterpenoids. The structures of sesquiterpenoids 1-3, including the absolute configurations, were determined by NMR spectroscopic, X-ray crystallography, and vibrational circular dichroism data analysis. Vetiverianine C (3) exhibited weak cytotoxic activity against HL-60 cells.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Vetiveria/química , Sesquiterpenos de Eudesmano/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Japão , Estrutura Molecular , Raízes de Plantas/química , Sesquiterpenos , Sesquiterpenos de Eudesmano/química , Sesquiterpenos de Eudesmano/farmacologia
10.
Nat Prod Commun ; 11(7): 983-985, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30452177

RESUMO

A new neolignan glycoside (1) and four known aromatic compounds (2-5) were isolated. from the roots of Vetiveria zizanioides. The structure of compound 1 was determined based on spectroscopic analysis and hydrolysis. The structure of known flavonoid glycoside 3 was confirmed by X-ray crystallography. Compound 5 showed weak cytotoxic activity against HL-60 cells with an IC50 value of 13.1 ± 0.04 µM.


Assuntos
Vetiveria/química , Glicosídeos/química , Raízes de Plantas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Glicosídeos/classificação , Células HL-60 , Humanos , Modelos Moleculares , Estrutura Molecular , Óleos Vegetais/química
11.
Future Med Chem ; 7(10): 1233-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26144262

RESUMO

BACKGROUND: In mammals, adrenaline and ATP are life-essential vicinal diol and cis-diol functional groups. Here, we show that interactions between a safe organogermanium compound and these cis-diol compounds have the potential to regulate physiological functions. In addition, we represent a possible new druggable target for controlling the action of cis-diol compounds. RESULTS: We analyzed a single crystal structure of organogermanium 3-(trihydroxygermyl)propanoic acid (THGPA), a hydrolysate of safe Ge-132, in complex with catecholamine (adrenaline and noradrenaline), and evaluated the affinity between several cis-diol compounds and THGPA by NMR. An in vitro study using normal human epidermal keratinocytes was performed to investigate the inhibition of cis-diol compound-stimulated receptors by THGPA. At high concentration, THGPA inhibited the calcium influx caused by adrenaline and ATP. CONCLUSION: This study demonstrates that THGPA can modify cis-diol-mediated cell-to-cell signaling.


Assuntos
Trifosfato de Adenosina/metabolismo , Epinefrina/metabolismo , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Catecolaminas/metabolismo , Linhagem Celular , Cristalografia por Raios X , Germânio/química , Germânio/farmacologia , Humanos , Hidrólise , Espectroscopia de Ressonância Magnética , Modelos Moleculares
12.
Org Lett ; 16(23): 6188-91, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25412277

RESUMO

A new, highly oxidized, bis-seco-abietane diterpenoid named hyptisolide A (1) was isolated from Hyptis crenata Pohl ex Benth. Its structure and stereochemistry were elucidated on the basis of data obtained by HRESIMS, NMR, and X-ray diffraction analyses, and its absolute configuration was determined with vibrational circular dichroism spectroscopy. By reporter gene assay, 1 was demonstrated to induce cAMP-responsive element-dependent transcription in Neuro2A cells.


Assuntos
Abietanos/isolamento & purificação , Hyptis/química , Abietanos/química , Abietanos/farmacologia , Animais , Cristalografia por Raios X , AMP Cíclico/metabolismo , Camundongos , Estrutura Molecular , Fármacos Neuroprotetores/metabolismo , Ressonância Magnética Nuclear Biomolecular , Componentes Aéreos da Planta/química
13.
Magn Reson Chem ; 52(4): 163-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24474589

RESUMO

The effects of doped low-valence cations on the properties of the SnP2 O7 proton conductor at ambient temperature are investigated from changes in solid-state NMR spectra and nuclear magnetic relaxation times. Although the T1 H values increased with decreasing acidity as a result of cation exchange, the (1)H chemical shifts moved to lower field in Al- and In-doped materials compared with undoped ones. Furthermore, the shifts changed to higher field in Mg-doped materials, suggesting the existence of different protonic species in those materials. The bulk phosphate chemical shifts in the (31)P dipolar-decoupling MAS NMR spectra were very similar, regardless of the nature and amount of the doping species. On the other hand, by (1)H/(31)P cross-polarization MAS NMR, P2O7 signals interacting with an interstitial proton [Q(1)(proton)] were observed in all the undoped and doped SnP2 O7, while acidic P-OH-type phosphate signals [Q(1)(acid)] were additionally observed in the Mg-doped conductor. The different affinity of the proton with the dopants and phosphates caused lower conductivity and larger activation energy in the Mg-doped materials, compared with those in the In- and Al-doped materials.

14.
Bioorg Med Chem Lett ; 24(2): 442-6, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24388808

RESUMO

A series of analogues of salviandulin E, a rearranged neoclerodane diterpene originally isolated from Salvia leucantha (Lamiaceae), were prepared and their in vitro activity against Trypanosoma brucei brucei was evaluated with currently used therapeutic drugs as positive controls. One of the 19 compounds prepared and assayed in the present study, butanoyl 3,4-dihydrosalviandulin E analogue was found to be a possible candidate for an antitrypanosomal drug with fairly strong antitrypanosomal activity and lower cytotoxicity.


Assuntos
Extratos Vegetais/síntese química , Extratos Vegetais/farmacologia , Salvia , Tripanossomicidas/síntese química , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Trypanosoma brucei brucei/fisiologia
15.
Mass Spectrom (Tokyo) ; 2(1): A0015, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24349916

RESUMO

Studies of clusters in condensed phase at atmospheric pressure are very important for understanding the properties and structures of liquids. Liquid-ionization (LPI) mass spectrometry is useful to study hydrogen-bonded clusters at the liquid surface and in a gas phase. An improved ion source connected to a tandem mass spectrometer provides detailed information about clusters. Mass spectra of pure ethanol (99.5%) observed by the first mass analyzer (Q1) showed neat ethanol cluster ions (C2H5OH) m H(+) with m up to 10 and hydrate ions (C2H5OH) m (H2O) n H(+) with m larger than 7 and n=1, such as those with m-n=8-1 and 9-1. When the flow rate of ethanol (liquid) was increased, large ethanol cluster ions with m larger than 25 were observed by the second mass analyzer (Q3). It is interesting to note that neat ethanol cluster ions are more abundant than corresponding (with the same m) hydrate ions (n=1), and major hydrate ions contain only one molecule of water. Results indicate that ion-molecule reactions occur between Q1 and Q3, because such mass spectra have never been observed by Q1. Various results indicate that neat ethanol clusters exist at the liquid surface and are ionized to give cluster ions.

16.
Chem Pharm Bull (Tokyo) ; 61(10): 1085-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24088701

RESUMO

A new alkaloid, stemona-lactam S, and a known alkaloid, tuberostemospiroline, were isolated from the roots of Stemona tuberosa LOUR. (Stemonaceae). Their structures and absolute stereochemistry were established by X-ray crystallography and vibrational circular dichroism.


Assuntos
Alcaloides/química , Lactamas/química , Compostos de Espiro/química , Stemonaceae/química , Alcaloides/isolamento & purificação , Dicroísmo Circular , Cristalografia por Raios X , Lactamas/isolamento & purificação , Conformação Molecular , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Compostos de Espiro/isolamento & purificação , Stemonaceae/metabolismo
17.
Chem Commun (Camb) ; 49(86): 10091-3, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24045875

RESUMO

Stable and easy-to-handle zwitterions containing carbanion and pyridinium moieties were synthesized, and their structural studies by both X-ray crystallography and theoretical methods revealed the stereoelectronic effect in the zwitterionic 'C(-)-C-N(+)' system.


Assuntos
Estabilidade de Medicamentos , Compostos de Piridínio/síntese química , Cristalografia por Raios X , Íons , Estrutura Molecular , Compostos de Piridínio/química
19.
J AOAC Int ; 95(4): 1048-52, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970570

RESUMO

A sildenafil-related compound was detected in a dietary supplement marketed as an aphrodisiac. The compound was detected during analysis of the dietary supplement using LC-UV and LC/electrospray ionization-MS. The structure of the compound was established using high resolution MS, NMR spectrometry, and X-ray crystal structure analysis. The compound was identified as 5-(5-((3,5-dimethylpiperazin-1-yl)sulfonyl)-2-ethoxyphenyl)-l-methyl-7-((1-methyl-4-nitro-1H-imidazol-5-yl)thio)-3-propyl-1H-pyrazolo[4,3-d] pyrimidine. Based on this structure, the compound was named nitroprodenafil. The dietary supplement was found to contain 90 mg nitroprodenafil/capsule. This article describes the structural characterization of a new sildenafil-related compound. The compound was detected during analysis of a dietary supplement using LC-UV and LC/electrospray ionization (ESI)-MS. The structure was established using high resolution MS (HRMS), NMR spectrometry, and X-ray crystal structure analysis. The structures of methisosildenafil, thiomethisosildenafil, and this new analog, named nitroprodenafil (21), are shown in Figure 1. In the Demizu et al. report, the compound is named mutaprodenafil instead ofnitroprodenafil. Considering the naming right, the authors of this paper think the use of mutaprodenafil is appropriate as the compound name, although nitroprodenafil is used.


Assuntos
Cromatografia Líquida/métodos , Suplementos Nutricionais/análise , Espectrometria de Massas/métodos , Piperazinas/análise , Sulfonas/análise , Cápsulas , Técnicas de Química Analítica/métodos , Cristalografia por Raios X/métodos , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Piperazinas/química , Purinas/análise , Purinas/química , Reprodutibilidade dos Testes , Citrato de Sildenafila , Espectrometria de Massas por Ionização por Electrospray/métodos , Sulfonas/química , Raios Ultravioleta
20.
Chemistry ; 18(10): 2839-46, 2012 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-22298232

RESUMO

Two bicyclic hexapeptides, allo-RA-V (4) and neo-RA-V (5), and one cyclic hexapeptide, O-seco-RA-V (6), were isolated from the roots of Rubia cordifolia L. Their gross structures were elucidated on the basis of spectroscopic analysis and X-ray crystallography of compound 5. The absolute stereochemistry of compounds 4 and 5 were established by their total syntheses, and the absolute stereochemistry of compound 6 by chemical correlation with deoxybouvardin (3). Comparison of the 3D structures of highly active RA-VII (1) with less-active compounds 4 and 5 suggests that the orientation of the Tyr-5 and/or Tyr-6 phenyl rings plays a significant role in their biological activity. The isolation of peptides 4-6, along with compound 3, and the comparison of their structures seem to indicate that peptide 6 may be the common precursor to bicyclic peptides 3-5 in the plant.


Assuntos
Peptídeos Cíclicos/síntese química , Rubia/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Células HL-60 , Humanos , Conformação Molecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Raízes de Plantas/química , Relação Estrutura-Atividade , Tirosina/química
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