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1.
J Chromatogr A ; 923(1-2): 87-96, 2001 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-11510564

RESUMEN

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.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Quinolinas/química , Quinolinas/aislamiento & purificación , Ácidos Sulfónicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Isomerismo , Espectroscopía de Resonancia Magnética
2.
Phytochemistry ; 55(6): 663-73, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11130678

RESUMEN

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.


Asunto(s)
Compuestos Heterocíclicos de 4 o más Anillos/aislamiento & purificación , Lactonas/aislamiento & purificación , Micotoxinas/aislamiento & purificación , Stachybotrys/química , Cristalografía por Rayos X , Compuestos Heterocíclicos de 4 o más Anillos/química , Lactonas/química , Espectroscopía de Resonancia Magnética , Conformación Molecular , Micotoxinas/química
3.
J Nat Prod ; 62(10): 1385-9, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10543898

RESUMEN

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.


Asunto(s)
Alcaloides/farmacología , Embrión de Mamíferos/efectos de los fármacos , Plantas Medicinales/química , Alcaloides/química , Animales , Técnicas de Cultivo , Femenino , Espectroscopía de Resonancia Magnética , Espectrometría de Masas/métodos , Embarazo , Ratas , Teratógenos/química , Teratógenos/farmacología
4.
J Nat Prod ; 59(10): 970-2, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8904846

RESUMEN

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).


Asunto(s)
Ácidos Carboxílicos/química , Fumonisinas , Micotoxinas/química , Piridinas/química , Ácidos Carboxílicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Micotoxinas/aislamiento & purificación , Piridinas/aislamiento & purificación , Espectrofotometría Ultravioleta
5.
J Nat Prod ; 58(9): 1392-7, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7494146

RESUMEN

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.


Asunto(s)
Fumonisinas , Fusarium/química , Micotoxinas/aislamiento & purificación , Acetilación , Fusarium/metabolismo , Cetonas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Micotoxinas/química , Micotoxinas/metabolismo , Zea mays/microbiología
7.
J Nat Prod ; 52(2): 426-7, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2746264

RESUMEN

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.


Asunto(s)
Alternaria/análisis , Benzo(a)Antracenos/aislamiento & purificación , Hongos Mitospóricos/análisis , Perileno/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Mutágenos , Perileno/análogos & derivados , Perileno/análisis
8.
J Nat Prod ; 49(5): 866-71, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3546597

RESUMEN

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.


Asunto(s)
Alternaria/análisis , Benzo(a)Antracenos/aislamiento & purificación , Hongos Mitospóricos/análisis , Mutágenos/aislamiento & purificación , Mutación , Benzo(a)Antracenos/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Mutagenicidad , Perileno/análogos & derivados , Salmonella typhimurium/efectos de los fármacos , Relación Estructura-Actividad
9.
J Med Chem ; 27(2): 239-44, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6694172

RESUMEN

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.


Asunto(s)
Leucemia Experimental/tratamiento farmacológico , Sesquiterpenos/síntesis química , Tricotecenos/síntesis química , Animales , Línea Celular , Fenómenos Químicos , Química , Compuestos Epoxi , Hidroxilación , Ratones , Relación Estructura-Actividad , Tricotecenos/uso terapéutico
13.
J Med Chem ; 23(9): 1054-8, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7411550

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/síntesis química , Animales , Compuestos Epoxi , Hidrólisis , Hidroxilación , Leucemia P388/tratamiento farmacológico , Ratones , Oxidación-Reducción , Relación Estructura-Actividad
15.
J Pharm Sci ; 69(2): 229-30, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7359336

RESUMEN

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


Asunto(s)
Minociclina/análisis , Oxitetraciclina/análogos & derivados , Oxitetraciclina/análisis , Rolitetraciclina/análisis , Tetraciclinas/análisis , Espectroscopía de Resonancia Magnética , Métodos
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