RESUMEN
Marine-derived fungi of the genera Aspergillus could produce novel compounds with significant bioactivities. Among these fungi, the strain Aspergillus flavus is notorious for its mutagenic mycotoxins production. However, some minor components with certain toxicities from A. flavus have not been specifically surveyed and might have potent biological activities. Our investigation of the marine-derived fungus Aspergillus flavus CF13-11 cultured in solid medium led to the isolation of four C-6'/C-7' epimeric drimane sesquiterpene esters, asperienes A-D (1-4). Their absolute configurations were assigned by electronic circular dichroism (ECD) and Snatzke's methods. This is the first time that two pairs of C-6'/C-7' epimeric drimane sesquiterpene esters have successfully been separated. Aperienes A-D (1-4) displayed potent bioactivities towards four cell lines with the IC50 values ranging from 1.4 to 8.3 µM. Interestingly, compounds 1 and 4 exhibited lower toxicities than 2 and 3 toward normal GES-1 cells, indicating more potential for development as an antitumor agent in the future.
Asunto(s)
Organismos Acuáticos/química , Aspergillus flavus/química , Hongos/química , Sesquiterpenos/química , Células A549 , Antineoplásicos/química , Línea Celular Tumoral , Dicroismo Circular/métodos , Células HeLa , Humanos , Células MCF-7 , Estructura Molecular , Sesquiterpenos Policíclicos/químicaRESUMEN
We report a method for synthesizing single-molecule magnets through a single-crystal to single-crystal transformation. This process yields two single-molecule magnets with similar triangular Dy3 cores but distinct solvents and space groups achieved via solvent exchange. Magnetic properties reveal that both Dy3 molecules exhibit similar toroidal moments but manifest diverse multiple magnetization dynamic behaviors owing to the spin-lattice coupling influence from different solvent molecules.
RESUMEN
A new epimer of azaphilone derivative pinophilin B, epi-pinophilin B (1), and three known analogues (2-4) were obtained from the culture of the gorgonian-derived fungus Aspergillus fumigatus 14-27. The structures of 1-4, including their relative configurations were determined by extensive spectroscopic analysis and comparing with literature data. The absolute configuration of 1 was determined by electronic circular dichroism (ECD) and optical rotatory (OR) calculations methods. Compounds 1-4 were isolated from A. fumigatus for the first time. Their antibacterial and cytotoxic activities were also evaluated.
Asunto(s)
Aspergillus fumigatus/química , Benzopiranos/química , Isocumarinas/química , Pigmentos Biológicos/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Benzopiranos/aislamiento & purificación , Benzopiranos/farmacología , Isocumarinas/aislamiento & purificación , Isocumarinas/farmacología , Pigmentos Biológicos/aislamiento & purificación , Pigmentos Biológicos/farmacología , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
In recent years, attributed to the excellent catalytic performance of precious metal materials, metal nanoparticles@MOF catalyst has been a popular research direction. Herein, we have synthesized a new 3D cobalt metal-organic framework [Co(TATAB)(344-pytpy)·DMF]n(H3TATAB = 4,4',4â³-s-triazine-1,3,5-triyltri-p-aminobenzoic acid; 344-pytpy = 4'-(3-pyridyl)-4,2':6',4â³-terpyridine)(1)(P1) by solvothermal method. Its crystal structure was determined with single-crystal X-ray diffraction (SC-XRD) techniques. The final composite Pd-NPs@1 catalyst was synthesized by a reduction method. The catalyst showed high catalytic performance and high recycling stability for nitrophenol degradation and cinnamaldehyde hydrogenation reaction.