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1.
Carbohydr Polym ; 98(2): 1335-42, 2013 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-24053811

RESUMEN

In this study, the biodegradable mucoadhesive 4-carboxybenzensulfonamide chitosan (4-CBS-chitosan)/poly (lactic acid) (PLA) nanoparticles were fabricated by the electrospray ionization technique for enhancing anti-topoisomerase II (Topo II) activity. The obtained (4-CBS-chitosan/PLA)-DOX nanoparticles were characterized using SEM, particle size analyzer. We emphasis on encapsulation efficiency, in vitro drug release behavior and also performed in vitro studies of Topo II inhibitory activity using gel electrophoresis. In addition, the cytotoxicity of the 4-CBS-chitosan/PLA nanoparticles using MTT assay was also studied. The mean particle size of spherical shaped (4-CBS-chitosan/PLA)-DOX is less than 300 nm. The DOX loaded 4-CBS-chitosan/PLA composite nanoparticles produced high entrapment efficiency of 85.8% and provided the prolonged release of DOX extended to 26 days and also still had strong Topo II inhibitory activity up to 77.4%. Overall, it was shown that 4-CBS-chitosan/PLA nanoparticles could be promising carriers for controlled delivery of anticancer drugs.


Asunto(s)
Quitosano/análogos & derivados , ADN-Topoisomerasas de Tipo II/química , Preparaciones de Acción Retardada/síntesis química , Portadores de Fármacos/síntesis química , Ácido Láctico/química , Nanopartículas/química , Polímeros/química , Sulfonamidas/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Doxorrubicina/farmacología , Composición de Medicamentos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Microscopía Electrónica de Rastreo , Nanopartículas/ultraestructura , Especificidad de Órganos , Tamaño de la Partícula , Plásmidos/efectos de los fármacos , Poliésteres
2.
Dalton Trans ; 42(37): 13747-53, 2013 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-23907310

RESUMEN

Metal halides, solvent effects, phase transfer catalysts, alkylating agent and reaction times were found to have important roles to complete halogen exchange reactions in "one pot" synthesis, starting from octakis(3-chloropropyl)octasilsesquioxane to obtain more reactive halide compounds: octakis(3-bromopropyl)octasilsesquioxane and octakis(3-iodopropyl)octasilsesquioxane. To confirm the complete halogen exchange, the desired products were characterized by (1)H, (13)C and (29)Si NMR spectroscopy, ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis.


Asunto(s)
Halógenos/química , Compuestos de Organosilicio/síntesis química , Modelos Moleculares , Estructura Molecular , Compuestos de Organosilicio/química
3.
Inorg Chem ; 51(22): 12266-72, 2012 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-23134535

RESUMEN

Novel phthalimide and o-sulfobenzimide-functionalized silsesquioxanes were successfully synthesized via nucleophilic substitution reactions from octakis(3-chloropropyl)octasilsesquioxane. Surprisingly, the formation of deca- and dodecasilsesquioxanes cages was discovered during substitution with phthalimide, but only octasilsesquioxane maintained a cage in the o-sulfobenzimide substitution reaction. Moreover, we report the electronic effect of nitrogen nucleophiles to promote cage-rearrangement of inorganic silsesquioxane core for the first time. Structures of products were confirmed by (1)H, (13)C, and (29)Si NMR spectroscopy, ESI-MS analysis, and single-crystal X-ray diffraction.

4.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): o1531, 2010 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-21587780

RESUMEN

THE TITLE COMPOUND [SYSTEMATIC NAME: (1R,4aR,7S,8aS,10aS)-1,4a,7-trimethyl-7-vinyl-1,2,3,4,4a,6,7,8,8a,9,10,10a-dodeca-hydro-phenanthrene-1-carb-oxy-lic acid], C(20)H(30)O(2), is a pimarane-type diterpene extracted from Croton oblongifolius. There are two independent mol-ecules in the asymmetric unit. In both of these, the six-membered rings A, B and C adopt chair, boat and half-chair conformations, respectively. Rings A and B are trans-fused. The two mol-ecules in the asymmetric unit form O-H⋯O hydrogen-bonded R(2) (2)(8) dimers. The absolute configuration was assigned on the basis of the published literature on analogous structures.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2310, 2010 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-21588659

RESUMEN

The title Schiff base compound, C(14)H(12)ClNO, was prepared from 4-chloro-benzyl-amine and salicyl-aldehyde. The mol-ecule is V-shaped: the dihedral angle between the aromatic rings is 67.51 (5)°. The rings are located on the opposite side of the C=N bond, giving an E configuration. An intra-molecular N-H⋯O hydrogen bond generates a S(6) ring. In the crystal structure, only weak non-classical C-H⋯O contacts are observed.

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2423, 2010 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-21588748

RESUMEN

In the title compound, C(7)H(10)N(2)·C(7)H(6)O(2), the components are linked by an O-H⋯N hydrogen bond. The mean planes of two mol-ecules form a dihedral angle of 78.68 (5)°. The crystal packing exhibits weak non-classical C-H⋯O contacts.

7.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3298, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-21589577

RESUMEN

In the title Schiff base compound, C(15)H(15)NO(2), prepared from 4-meth-oxy-benzyl-amine and salicyl-aldehyde, an intra-molecular O-H⋯N hydrogen bonds influences the mol-ecular conformation; the two aromatic rings form a dihedral angle of 73.5 (1)°. In the crystal, weak inter-molecular C-H⋯O inter-actions link the mol-ecules into chains propagating in [010].

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