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1.
J Chromatogr A ; 923(1-2): 87-96, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11510564

RESUMO

The main components of the color additive D&C Yellow No. 10 (Quinoline Yellow, Color Index No. 47005), 2-(2-quinolinyl)-1H-indene-1,3(2H)-dione-6'-sulfonic acid (6SA) and 2-(2-quinolinyl)-1H-indene-1,3(2H)-dione-8'-sulfonic acid (8SA), were isolated from the dye mixture by pH-zone-refining counter-current chromatography (CCC) in the ion-exchange mode. These positional isomers were separated from a portion of dye using sulfuric acid as the retainer acid and dodecylamine as the ligand (ion exchanger). The added ligand enhanced the partitioning of the hydrophilic components in the organic stationary phase of the two-phase solvent system that consisted of isoamyl alcohol-methyl tert.-butyl ether-acetonitrile-water (3:1:1:5). Thus, separation of 1.8 g of D&C Yellow No. 10 using the above method resulted in 0.6 g of 6SA and 0.18 g of 8SA of over 99% purity. The isolated compounds were characterized by mass spectrometry and proton nuclear magnetic resonance with correlated spectroscopy assignments. The study exemplifies a new field of applications for pH-zone-refining CCC, to the separation of positional isomers of strongly hydrophylic compounds containing sulfonic acid groups.


Assuntos
Cromatografia por Troca Iônica/métodos , Quinolinas/química , Quinolinas/isolamento & purificação , Ácidos Sulfônicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Isomerismo , Espectroscopia de Ressonância Magnética
2.
Phytochemistry ; 55(6): 663-73, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11130678

RESUMO

Atranones A-G have been isolated from the toxigenic fungus Stachybotrys chartarum. These compounds contain several unusual features including an enol-lactone as part of a 3,7-dioxabicyclo[3.3.0]octane-2-one ring system fused to an 11-membered ring. Two new dolabellane diterpenes, related in structure to the atranones were also isolated, which suggests a diterpenoid origin for the C24 atranones.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Lactonas/isolamento & purificação , Micotoxinas/isolamento & purificação , Stachybotrys/química , Cristalografia por Raios X , Compostos Heterocíclicos de 4 ou mais Anéis/química , Lactonas/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Micotoxinas/química
3.
J Nat Prod ; 62(10): 1385-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10543898

RESUMO

The novel alkaloid thalictroidine (1), as well as the known alkaloids taspine (2), magnoflorine (3), anagyrine (4), baptifoline (5), 5,6-dehydro-alpha-isolupanine (6), alpha-isolupanine (7), lupanine (8), N-methylcytisine (9), and sparteine (10), were identified from an extract of Caulophyllum thalictroides rhizomes. N-Methylcytisine exhibited teratogenic activity in the rat embryo culture (REC), an in vitro method to detect potential teratogens. The structure of 1 was elucidated using various spectroscopic methods, primarily by NMR techniques. Thalictroidine, anagyrine, and alpha-isolupanine were not teratogenic in the REC at tested concentrations. Taspine (2) showed high embryotoxicity, but no teratogenic activity, in the REC.


Assuntos
Alcaloides/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Plantas Medicinais/química , Alcaloides/química , Animais , Técnicas de Cultura , Feminino , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Gravidez , Ratos , Teratogênicos/química , Teratogênicos/farmacologia
4.
J Nat Prod ; 59(10): 970-2, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8904846

RESUMO

A new series of fumonisins, designated FP1-3, were isolated from a culture of Fusarium moniliforme (M-2285) grown on solid corn. The new compounds contain a 3-hydroxypyridinium moiety at the C-2 position of the eicosane backbone instead of the amine found in the B series of fumonisins. The new fumonisins were characterized by UV, LC-MS-MS, 1H NMR, and 13C NMR. LC-MS analysis of culture extracts indicates that the new fumonisins can occur at levels up to approximately one-third the amount of their amine-containing analogues (FB1, FB2, and FB3).


Assuntos
Ácidos Carboxílicos/química , Fumonisinas , Micotoxinas/química , Piridinas/química , Ácidos Carboxílicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Micotoxinas/isolamento & purificação , Piridinas/isolamento & purificação , Espectrofotometria Ultravioleta
5.
J Nat Prod ; 58(9): 1392-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7494146

RESUMO

A method is presented for the separation and identification of a new N-acetyl keto derivative of fumonisin B1 (FB1) produced in solid corn culture. Cultures of Fusarium proliferatum (M-1597) were purified using preparative hplc, and the new fumonisin was detected by negative-ion esms. Structures were confirmed by 1H- and 13C-nmr spectroscopy. The new fumonisin differs from FB1 in that the tricarballylic acid functionality at the C-15 position of the eicosane backbone is replaced by a ketone and the amino group is acetylated. Direct analysis of the culture material by negative-ion electrospray lc/ms confirmed that the new fumonisin is produced naturally by the fungus.


Assuntos
Fumonisinas , Fusarium/química , Micotoxinas/isolamento & purificação , Acetilação , Fusarium/metabolismo , Cetonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Micotoxinas/química , Micotoxinas/metabolismo , Zea mays/microbiologia
7.
J Nat Prod ; 52(2): 426-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2746264

RESUMO

Stemphyltoxin III, (6aR*, 6bS*, 7R*, 8R*)-3,6a, 10-trihydroxy-4,9-dioxo-4,6a,6b,7,8,9-hexahydro-7,8-epoxyperylene, a known metabolite of Stemphylium botryosum var. lactucum, has been identified as a mutagenic metabolite of Alternaria alternata by spectroscopic studies. The 13C-nmr spectral data, which were not reported previously, are presented.


Assuntos
Alternaria/análise , Benzo(a)Antracenos/isolamento & purificação , Fungos Mitospóricos/análise , Perileno/isolamento & purificação , Espectroscopia de Ressonância Magnética , Mutagênicos , Perileno/análogos & derivados , Perileno/análise
8.
J Nat Prod ; 49(5): 866-71, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3546597

RESUMO

The mold genus Alternaria is a widely distributed plant pathogen. Some of these species, e.g., A. alternata, are common decay organisms of fruits and vegetables. Two novel perylene oxide metabolites, altertoxins II and III, have been identified in extracts of A. alternata isolates that exhibit mutagenic responses in the Ames Salmonella typhimurium assay. These identifications were based on mass, optical rotational, and 1H- and 13C-nmr spectral studies. Previous reports of related perylene dione mycotoxins have been clarified.


Assuntos
Alternaria/análise , Benzo(a)Antracenos/isolamento & purificação , Fungos Mitospóricos/análise , Mutagênicos/isolamento & purificação , Mutação , Benzo(a)Antracenos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Mutagenicidade , Perileno/análogos & derivados , Salmonella typhimurium/efeitos dos fármacos , Relação Estrutura-Atividade
9.
J Med Chem ; 27(2): 239-44, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6694172

RESUMO

Various 8 beta-hydroxy, 16-hydroxy, and 9 beta,10 beta-epoxy derivatives of roridins A and H and verrucarins A and J have been prepared and tested in vivo against P388 mouse leukemia. The 9 beta,10 beta-epoxy derivatives and 16-hydroxy derivatives consistently exhibit very high activity. The 8 beta-hydroxy-9 beta,10 beta-epoxy and 16-hydroxy-9 beta,10 beta-epoxy derivatives of verrucarin A and roridin A exhibit extraordinary activity against P388. The 8 beta-hydroxy-9 beta,10 beta-epoxy and 16-hydroxy-9 beta,10 beta-epoxy derivatives of verrucarin A and roridin A exhibit extraordinary against P388.


Assuntos
Leucemia Experimental/tratamento farmacológico , Sesquiterpenos/síntese química , Tricotecenos/síntese química , Animais , Linhagem Celular , Fenômenos Químicos , Química , Compostos de Epóxi , Hidroxilação , Camundongos , Relação Estrutura-Atividade , Tricotecenos/uso terapêutico
13.
J Med Chem ; 23(9): 1054-8, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7411550

RESUMO

Verrucarin A (2) was epoxidized to give the beta-9,10-epoxide 7 (major product) and alpha-9,10-epoxide 9 (minor product). The beta-epoxide 7 and its acetate 8 exhibit high in vivo antileukemic activity against P-388 mouse leukemia, whereas 2 and 9 are inactive. Epoxidation of verrucarin B (3) and roridin A (1) to their respective beta-9,10-epoxides (11 and 12, respectively) also yields compounds with substantially increased activity. Allylic alcohols derived from 2, alpha-C8 (20), beta-C8 (14), and C16 (15), were synthesized and tested; only 15 exhibited substantial in vivo activity.


Assuntos
Antineoplásicos Fitogênicos/síntese química , Animais , Compostos de Epóxi , Hidrólise , Hidroxilação , Leucemia P388/tratamento farmacológico , Camundongos , Oxirredução , Relação Estrutura-Atividade
15.
J Pharm Sci ; 69(2): 229-30, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7359336

RESUMO

13C-NMR data and spectral assignments are presented for tetracycline antibiotics minocycline hydrochloride, meclocycline, and rolitetracycline.


Assuntos
Minociclina/análise , Oxitetraciclina/análogos & derivados , Oxitetraciclina/análise , Rolitetraciclina/análise , Tetraciclinas/análise , Espectroscopia de Ressonância Magnética , Métodos
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