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1.
Chemistry ; 22(30): 10459-74, 2016 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-27319279

RESUMO

A bidentate ligand, 1-{4-[4-(1H-1,2,4-triazol-1-yl)phenoxy]phenyl}-1H-1,2,4-triazole (TPPT), has been designed and synthesized. By using TPPT as a building block for self-assembly with Cd(NO3 )2 ⋅4 H2 O and CdCl2 ⋅10.5 H2 O, novel 1D double-chain {[Cd(TPPT)(NO3 )2 ]⋅3 H2 O}n (1) and 2D (4,4) layer [Cd(TPPT)Cl2 (H2 O)]n (2) have been constructed. When 1 was employed as a precursor and exposed to DMF or N,N'-dimethylacetamide (DMAC), the crystals of 1 dissolved and reassembled into two types of brown block-shaped crystals of 1D double chains: {[Cd(TPPT)2 (NO3 )2 ]⋅DMF}n (1 a) and {[Cd(TPPT)2 (NO3 )2 ]⋅DMAC}n (1 b). The anion-exchange reactions of complex 2 have also been investigated. After gently stirring crystals of 2 in CHCl3 /C2 H5 OH/H2 O containing NaBr, NaI⋅2 H2 O, or NaOAc⋅3 H2 O, the crystals retained their crystalline appearances. A remarkable single crystal to single crystal transformation was observed and 1D double chains of {[Cd(TPPT)Br2 ]⋅C2 H5 OH}n (2 a) and {[Cd(TPPT)2 I2 ]⋅CHCl3 }n (2 b), and 1D single chains of [Cd(TPPT)(H2 O)2 (CH3 COO)2 ]n (2 c), can be obtained. Luminescent properties indicate that 1 shows excellent selectivity for Ca(2+) and cyano complexes. To the best of our knowledge, this is the first example of a luminescent probe for Ca(2+) based on triazole derivatives.

2.
Bioorg Med Chem ; 18(14): 4879-83, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20598551

RESUMO

Bioassay-guided (murine P388 lymphocytic leukemia and human cancer cell lines) separation of an ethyl acetate extract prepared from the inky cap fungus Coprinus cinereus led to the isolation of three new sesquiterpenes, 7,7a-diepicoprinastatin 1 (1), 14-hydroxy-5-desoxy-2S,3S,9R-illudosin (2), and 4,5-dehydro-5-deoxyarmillol (3), together with the known armillol (4). The structure and relative configuration of 1 was determined by single-crystal X-ray diffraction experiments. The structures of compounds 2, 3, and 4 were each deduced by a combination of HRMS and 1D and 2D NMR techniques. Cyclobutane 2 led to modest inhibition of the murine P388 leukemia cell line.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Coprinus/química , Neoplasias/tratamento farmacológico , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Animais , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ciclobutanos/química , Humanos , Camundongos , Modelos Moleculares , Sesquiterpenos/isolamento & purificação
3.
J Nat Prod ; 73(3): 409-15, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20108948

RESUMO

Amphidinol 17 (AM17; 1), a novel amphidinol, has been isolated from a Bahamas strain of Amphidinium carterae. This new congener contains the signature hairpin region and a Delta(6) polyene arm, whereas the polyol arm is distinct from those of other amphidinols. The pattern of acetate incorporation in 1 was directly determined by feeding a single labeled substrate, [2-(13)C]acetate. While the highly conserved regions within the amphidinol family of AM17 have exhibited identical occurrences of cleaved acetates to other amphidinols for which the biosynthesis has been explored, the polyol arm for AM17 displays a higher degree of nascent chain processing that shows similarities to amphidinolide biosynthesis. AM17 exhibited an EC(50) of 4.9 microM in a hemolytic assay using human red blood cells but displayed no detectable antifungal activity.


Assuntos
Dinoflagellida/química , Lactonas/química , Animais , Humanos , Lactonas/sangue , Lactonas/síntese química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Relação Estrutura-Atividade
4.
J Nat Prod ; 73(3): 388-92, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-19919060

RESUMO

Cancer cell line bioassay-guided separation of an ethyl acetate extract prepared from a plant-associated fungus, Coprinus cinereus, led to the isolation of three new sesquiterpenes, coprinastatin 1 (1), coprinol (2), and the epimer (4a), of the known sesquiterpene triol (4b). The previously described sesquiterpene 3 and oxazolinone 5 were also isolated. The structure and relative configuration of coprinastatin 1 (1) were determined by HRMS and by 1D- and 2D-NMR spectroscopic analyses. The structure of terpene 2 was elucidated by single-crystal X-ray diffraction experiments. The remaining structures were similarly determined, structure 3 by spectroscopic analyses and both 4a and 5 by X-ray crystal structure determination. Coprinastatin 1 (1) was found to inhibit growth of the murine P388 lymphocytic leukemia cell line and the pathogenic bacterium Neisseria gonorrhoeae.


Assuntos
Antineoplásicos , Neisseria gonorrhoeae/efeitos dos fármacos , Sesquiterpenos , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Leucemia P388 , Camundongos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Estereoisomerismo
5.
Phytochemistry ; 69(14): 2603-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18771781

RESUMO

Halophila johnsonii Eiseman is a shallow-water marine angiosperm which contains UV-absorbing metabolites. Studies on methanol extracts of H. johnsonii by means of HPLC-UV, NMR, HPLC-MS resulted in isolation and identification of seven previously unknown flavone glycosides: 5,6,7,3',4',5'-hexahydroxyflavone-7-O-beta-glucopyranoside (1), 5,6,7,3',4',5'-hexahydroxyflavone-7-O-(6''-O-acetyl)-beta-glucopyranoside (2), 6-hydroxyluteolin-7-O-(6''-O-acetyl)-beta-glucopyranoside (3), 6-hydroxyapigenin-7-O-(6''-O-acetyl)-beta-glucopyranoside (4), 6-hydroxyapigenin-7-O-(6''-O-[E]-coumaroyl)-beta-glucopyranoside (5), 6-hydroxyapigenin-7-O-(6''-O-[E]-caffeoyl)-beta-glucopyranoside (6) and 6-hydroxyluteolin-7-O-(6''-O-[E]-coumaroyl)-beta-glucopyranoside (7). Also isolated were three known flavone glycosides, 6-hydroxyluteolin 7-O-beta-glucopyranoside (8), scutellarein-7-O-beta-glucopyranoside (9), and spicoside (10), and five known flavones, pedalitin (11), ladanetin (12), luteolin (13), apegenin (14) and myricetin (15). Qualitative comparison of the flavonoid distribution in the leaf and rhizome-root portions of the plant was also investigated, with the aim of establishing the UV-protecting roles that flavonoids played in the sea grass.


Assuntos
Flavonoides/química , Glicosídeos/química , Hydrocharitaceae/química , Cromatografia Líquida de Alta Pressão , Flavonas , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Hydrocharitaceae/efeitos da radiação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta/química , Rizoma/química , Raios Ultravioleta
6.
Oncol Res ; 15(2): 59-68, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16119003

RESUMO

The CH3OH-CH2Cl2 extract of an Indian collection (entire plant) of Gynandropsis gynandra (L.) Briq. was separated based on bioassay results employing cancer cell lines. Six cancer cell growth inhibitors were isolated and found to be known flavone apegenin (4) and flavonols 1-3, 5, and 6. The structure of flavonol 2 was confirmed by X-ray crystal structure determination. All of the five flavonols (1-3, 5, 6) inhibited the murine P388 lymphocytic leukemia cell line with ED50 values of 3.0, 9.2, 4.0, 0.37, and 3.9 microg/ml, respectively. All six of the flavonoids (1-6) also exhibited activity against a panel of six human cancer cell lines. Penduletin (3) inhibited growth of the Gram-negative pathogen Neisseria gonorrhoeae and apegenin (4) inhibited growth of the Gram-positive opportunist Enterococcus faecalis.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Animais , Anisotropia , Anti-Infecciosos/farmacologia , Bioensaio , Linhagem Celular Tumoral , Proliferação de Células , Cristalografia por Raios X , Enterococcus faecalis/metabolismo , Flavonas , Flavonóis/química , Humanos , Ligação de Hidrogênio , Camundongos , Modelos Químicos , Modelos Moleculares , Neisseria gonorrhoeae/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais/metabolismo , Células Tumorais Cultivadas
7.
J Nat Prod ; 68(8): 1256-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16124772

RESUMO

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines) guided separation of an extract prepared from the previously chemically uninvestigated Texas grasshopper Brachystola magna led to isolation of the cancer cell growth inhibitory pancratistatin (1), narciclasine (2), and ungeremine (3). Pancratistatin (1) was first isolated from the bulbs of Hymenocallis littoralis), and the original crystal structure was deduced by X-ray analysis of a monomethyl ether derivative. In the present study pancratistatin (1) was isolated from an extract of B. magna, which led to the X-ray crystal structure of this anticancer drug. Since isoquinoline derivatives 1-3 are previously known only as constituents of amaryllidaceous plants, some of the interesting implications of their rediscovery in the grasshopper B. magna that does not appear to utilize amaryllis family plants were discussed.


Assuntos
Antineoplásicos/isolamento & purificação , Alcaloides de Amaryllidaceae , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Gafanhotos , Humanos , Indolizinas , Isoquinolinas , Leucemia P388 , Conformação Molecular , Estrutura Molecular , Fenantridinas , Células Tumorais Cultivadas
8.
J Nat Prod ; 67(2): 214-20, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14987061

RESUMO

Bioassay (P388 lymphocytic leukemia cell line and human tumor cell lines)-guided separation of the extracts prepared from the tropical and coastal trees Hernandia peltata (Malaysia) and Hernandianymphaeifolia (Republic of Maldives) led to the isolation of a new lignan designated as hernanol (1) and 12 previously known lignans: (-)-deoxypodophyllotoxin (2), deoxypicropodophyllin (3), (+)-epiaschantin (4), (+)-epieudesmin (5), praderin (6), 5'-methoxyyatein (7), podorhizol (8), deoxypodorhizone (9), bursehernin (10), kusunokinol (11), clusin (12), and (-)-maculatin (13). The oxidative cyclization (with VOF(3)) of lignans 8, 9, and 10 resulted in a new and unusual benzopyran (14), isostegane (15), and a new dibenzocyclooctadiene lactone (16), respectively. The structure and relative stereochemistry of hernanol (1) and lignans 3, 7, 8, 9, 10, 11, and 12 were determined by 1D and 2DNMR and HRMS analyses. The structures and absolute stereochemistry of structures 2, 4, 5, 6, 13, 14, 15, and 16 were unequivocally determined by single-crystal X-ray diffraction analyses. Evaluation against the murine P388 lymphocytic leukemia cell line and human tumor cell lines showed podophyllotoxin derivatives 2 and 3 to be strong cancer cell line growth inhibitors and substances 4, 5, 8, and 15 to have marginal cancer cell line inhibitory activities. Seven of the lignans and one of the synthetic modifications (14) inhibited growth of the pathogenic bacterium Neisseria gonorrhoeae.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Lignanas/isolamento & purificação , Plantas Medicinais/química , Árvores/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ilhas do Oceano Índico , Leucemia P388 , Lignanas/química , Lignanas/farmacologia , Malásia , Camundongos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Neisseria gonorrhoeae/efeitos dos fármacos , Células Tumorais Cultivadas
9.
J Nat Prod ; 66(8): 1065-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12932125

RESUMO

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines)-guided separation of an extract prepared from the stem bark and twigs of the previously uninvestigated Ruprechtia tangarana led to the isolation of a new isocarbostyril designated ruprechstyril (1), secalonic acid A (2), 2'-O-methylevernic acid (3), 3,3',4-tri-O-methylflavellagic acid (4), lichexanthone (5), methyl asterrate (6), and 3beta,22E,24S-stigmasta-5,22-dien-3-ol (7). Only secalonic acid A exhibited cancer cell and microbial growth inhibition. The structure of ruprechstyril (1) was determined by HRMS and 1D and 2D NMR spectra and confirmed by single-crystal X-ray analysis. The structures and absolute stereochemistry of five of the other compounds were also established by X-ray crystal structure determination.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Hidroxiquinolinas/isolamento & purificação , Plantas Medicinais/química , Polygonaceae/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidroxiquinolinas/química , Hidroxiquinolinas/farmacologia , Leucemia P388 , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peru , Estereoisomerismo
10.
J Nat Prod ; 66(2): 259-62, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12608861

RESUMO

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines) guided separation of an extract prepared from the leaves of Hymenaea palustris Ducké led to the isolation of six cancer cell growth inhibitory flavonoids (1-6). The structures were elucidated by HRMS and 1D and 2D NMR spectral analysis. The new flavonolignan 1 designated palstatin proved to be a methoxy structural modification of 5'-methoxyhydnocarpin-D (2). Flavones 1-4 inhibited growth of the pathogenic bacteria Enterococcus faecalis and/or Neisseria gonorrhoeae.


Assuntos
Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Fabaceae/química , Flavonoides/isolamento & purificação , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Enterococcus faecalis/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Humanos , Concentração Inibidora 50 , Leucemia P388 , Camundongos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Neisseria gonorrhoeae/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Peru , Folhas de Planta/química , Árvores/química , Células Tumorais Cultivadas/efeitos dos fármacos
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