RESUMEN
A Pd-catalysed regioselective synthesis of 4,5-disubstituted 7-membered N/O-heterocycles was achieved via the 7-endo-dig cyclization followed by C-C bond formation of 2-(1-alkynyl)phenylacetamide. The ligand/additive free cascade reaction proceeded in the presence of PdCl2 in aqueous MeCN when the separate and individual use of methyl vinyl ketone and allyl bromide generally afforded an O- and N-heterocycle, respectively. The pharmacological assay was performed to identify the first example of a 1H-benzo[d]azepin-2(3H)-one based novel inhibitor of PDE4B.
RESUMEN
A novel fluorescent chemosensor naphthyridine-boronic acid derivative (1.1) was synthesized and its ability to act as a selective chemosensor was examined for various metal ions. Compound 1.1 displayed highly selective fluorescence quenching upon interaction with Hg2+, possibly by means of photo induced electron transfer (PET) mechanism. The binding stoichiometry of the naphthyridine-boronic acid-Hg2+ complex and the association constant was determined. It was found that in the presence of d-fructose at physiological concentration, the sensitivity of chemosensor 1.1 towards Hg2+ improved by at least 7 times, perhaps as a result of the cooperative binding of both d-fructose and mercury ion to the sensor. Till now, the presented dual d-fructose-mercury chemosensor is the first example of utilizing boronic acid-diol complexation for enhancement of the sensor's sensitivity towards a toxic metal ion. The utility of compound 1.1 lays in applications in the food industry, e.g. for detection of mercury contamination of high fructose corn syrup, or in estimation of mercury in polluted biological samples and underground water.
RESUMEN
Lung cancer is the single largest cause of cancer related deaths in the world. Current treatments include surgery, radiation therapy, chemotherapy using cytotoxic drugs, and monoclonal antibodies. Such treatments have limited efficacy due to diverse nature of lung cells involved and lack of tissue penetration. Cytotoxic drugs, while potent, have the enormous drawback of limited entry into the lung selectively, thus causing collateral damage to other tissues. To overcome these shortcomings, we report here the development of new magnetic irinotecan containing nanoparticles (NPs), which target the lung over other tissues by over 5-fold. Selective targeting of lungs is achieved by deliberately incorporating a facilitated transport mechanism into the NPs. The iron containing NPs can be further exploited to retain the drug into the lung for maximum efficacy using an external magnet. This irinotecan nanoformulation can be used as mono therapy or combination therapy and offers a cost-effective and efficacious therapy for lung cancers.
Asunto(s)
Portadores de Fármacos/química , Irinotecán/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Nanopartículas de Magnetita/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Irinotecán/química , Irinotecán/farmacocinética , Ratones , Conejos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Glowing fish: Fluorescent organic nanoparticles (FONs) were prepared from pyrene-containing guanine analogues. FONs are able to penetrate into human cells and zebrafish embryos; they are nontoxic, biocompatible and were found to be specific for muscular tissues. This study demonstrates for the first time the possibility of using FONs for in vivo, whole-body, fluorescence imaging of zebrafish.