Search results for "MACRO"
showing 10 items of 3471 documents
Synthesis and biological evaluation of 2- and 3-aminobenzo[b]thiophene derivatives as antimitotic agents and inhibitors of tubulin polymerization.
2007
Two new series of inhibitors of tubulin polymerization based on the 2-amino-3-(3,4,5-trimethoxybenzoyl)benzo[b]thiophene molecular skeleton and its 3-amino positional isomer were synthesized and evaluated for antiproliferative activity, inhibition of tubulin polymerization, and cell cycle effects. Although many more 3-amino derivatives have been synthesized so far, the most promising compound in this series was 2-amino-6-methyl-3-(3,4,5-trimethoxybenzoyl)benzo[b]thiophene, which inhibits cancer cell growth at subnanomolar concentrations and interacts strongly with tubulin by binding to the colchicine site.
Crystallization and preliminary X-ray studies of mouse centrin1.
2005
The expression, purification, crystallization and preliminary X-ray diffraction studies of mouse centrin1 are reported. Centrins belong to a family of Ca{sup 2+}-binding EF-hand proteins that play a fundamental role in centrosome duplication and the function of cilia. To shed light on the structure–function relationship of these proteins, mouse centrin1 has been crystallized. The mouse centrin1 has been expressed in Escherichia coli as a GST-centrin fusion protein containing a thrombin protease cleavage site between the fusion partners. Two constructs with different linking-sequence lengths were expressed and purified. Thrombin cleavage yielded functional centrin1 and N-terminally extended …
Activity of lupane triterpenoids from Maytenus species as inhibitors of nitric oxide and prostaglandin E2
2005
In the present study, we report that three new lupane triterpenes (1-3), in addition to 16 known ones (4-19), were isolated from the root bark of Maytenus cuzcoina and the leaves of Maytenus chiapensis. Their structures were elucidated by spectral analysis, including homonuclear and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC, and HMBC). The natural compounds and derivatives 6a, 6b, 9a, and 9b have been tested for potential anti-inflammatory activity, and several compounds including 3-epicalenduladiol (2), 11alpha-hydroxy-glochidone (3), rigidenol (6), acetoxy-rigidenol (6a), 11alpha-acetoxy-30-chloro-3-oxo-lup-20(29)-ene (6b), betulin (9), 28-acetoxy-betulin (9a), epibetul…
Synthesis and biological evaluation of 2-(3',4',5'-trimethoxybenzoyl)-3-N,N-dimethylamino benzo[b]furan derivatives as inhibitors of tubulin polymeri…
2008
Molecules that target microtubules have an important role in the treatment of cancer. A new class of inhibitors of tubulin polymerization based on the 2-(3,4,5-trimethoxybenzoyl)-2-dimethylamino-benzo[b]furan molecular skeleton was synthesized and evaluated for antiproliferative activity, inhibition of tubulin polymerization, and cell cycle effects. The most promising compound in this series was 2-(3,4,5-trimethoxybenzoyl)-3-dimethylamino-6-methoxy-benzo[b]furan, which inhibits cancer cell growth at nanomolar concentrations and interacts strongly with tubulin by binding to the colchicine site.
Polysaccharide/polyaminoacid composite scaffolds for modified DNA release.
2009
Abstract In this work composite polymeric films or sponges, based on hyaluronic acid (HA) covalently crosslinked with α,β-poly(N-2-hydroxyethyl)(2-aminoethylcarbamate)- d , l -aspartamide (PE), have been prepared and characterized as local gene delivery systems. In particular, HA/PE scaffolds have been loaded with PE/DNA interpolyelectrolyte complexes, employing PE as a macromolecular crosslinker for HA and as a non-viral vector for DNA. In vitro studies showed that HA/PE films and sponges have high compatibility with human dermal fibroblasts and they give a sustained DNA release, whose trend can be easily tailored by varying the crosslinking ratio between HA and PE. Electrophoresis analysi…
Synthesis, spectroscopic characterization and electrochemical behaviour of nickel(II) complexes with C-meso-5,5,7,12,12,14-hexamethylcyclotetradecane…
1993
A series of complexes of formula {Ni(Me6[14]aneN4)X2| (Me6[14]aneN4) = C-meso-5,5,7,12,12,14-hexamethyl-1,4,-8,11-tetraazacyclotetradecane and X = N3(1), NCO (2), NCS (3), AcO (4) or I (5) has been synthesized. The crystal structure of (5) has been determined by X-ray diffraction methods. The nickel atom is surrounded by a square-planar array of nitrogen atoms, giving a low-spin complex. The macrocyclic ligand shows the most stable conformation, the six-membered rings exhibiting the chair form while the gauche conformation is adopted by the five-membered rings. Spectroscopic and magnetic data for (1)–(4) are consistent with octahedral coordination around the nickel atom, which is achieved b…
Cytotoxic 14-Membered Macrolides from a Mangrove-Derived Endophytic Fungus, Pestalotiopsis microspora.
2016
Seven new 14-membered macrolides, pestalotioprolides C (2), D-H (4-8), and 7-O-methylnigrosporolide (3), together with four known analogues, pestalotioprolide B (1), seiricuprolide (9), nigrosporolide (10), and 4,7-dihydroxy-13-tetradeca-2,5,8-trienolide (11), were isolated from the mangrove-derived endophytic fungus Pestalotiopsis microspora. Their structures were elucidated by analysis of NMR and MS data and by comparison with literature data. Single-crystal X-ray diffraction analysis was used to confirm the absolute configurations of 1, 2, and 10, while Mosher's method and the TDDFT-ECD approach were applied to determine the absolute configurations of 5 and 6. Compounds 3-6 showed signif…
Potassium Triggers a Reversible Specific Stiffness Transition of Polyethylene Glycol
2017
We use plasmon rulers made from two connected gold nanoparticles to monitor the conformation and stiffness of single PEG molecules and their response to cations. By observing equilibrium fluctuations of the interparticle distance, we obtain the spring constants or stiffness of the connecting single-molecule tether with pico-Newton sensitivity. We observe a transition of the PEG molecules’ extension and stiffness above about 1.2 mM K+ ion concentration which is specific to potassium ions. Molecular dynamics simulations reveal the formation of crown-like structures as the most likely molecular mechanism responsible for this specific effect.
Inclusion complexes of Cethyl-2-methylresorcinarene and pyridine N-oxides: breaking the C–I⋯−O–N+ halogen bond by host–guest complexation
2016
C ethyl-2-Methylresorcinarene forms host–guest complexes with aromatic N-oxides through multiple intra- and intermolecular hydrogen bonds and C–H⋯π interactions. The host shows conformational flexibility to accommodate 3-methylpyridine N-oxide, while retaining a crown conformation for 2-methyl- and 4-methoxypyridine N-oxides highlighting the substituent effect of the guest. N-Methylmorpholine N-oxide, a 6-membered ring aliphatic N-oxide with a methyl at the N-oxide nitrogen, is bound by the equatorial −N–CH3 group located deep in the cavity. 2-Iodopyridine N-oxide is the only guest that manifests intermolecular N–O⋯I–C halogen bond interactions, which are broken down by the host resulting i…
Binuclear Cu2+ complex mediated discrimination between L-glutamate and L-aspartate in water.
2005
L-Glutamate and L-aspartate selectivity is achieved by the action of two Cu2+ metal ions rightly disposed in a cyclophanetype macrocyclic framework; electrochemical sensing of glutamate has been achieved by adsorption of the copper complexes on graphite electrodes. Verdejo Viu, Begoña, Begona.Verdejo@uv.es ; Domenech Carbo, Antonio, Antonio.Domenech@uv.es ; Jimenez Garcia, Hermas Rafael, Hermas.Jimenez@uv.es ; Soriano Soto, Concepción, Concepcion.Soriano@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es