Search results for "combinatorial"

A facile way to build up branched high functional polyaminoacids with tunable physicochemical and biological properties

2016

Abstract Here, for the first time, branched polyaminoacids bearing α-amino acids as side functions, namely PAA-co-AA and PGA-co-AA, are prepared by heterophase ring opening of polysuccinimide (PSI) with l -arginine or glycine in aqueous environment and at controlled pH. The modulation of the pH of the reaction leads to high-molecular-weight copolymers with tunable functionalization and, as consequence, with tailor-made physicochemical properties. Furthermore, a branched polyaminoacid carrying a preformed bioactive peptide ( l -trileucine) and l -arginine as side pendants, named PATA-co-AA, was synthesized via a similar pathway thus leading to complex biomimetic materials potentially exploit…

New benzothieno[3,2-d]-1,2,3-triazines with antiproliferative activity: synthesis, spectroscopic studies, and biological activity.

2014

New benzothieno[3,2-d]-1,2,3-triazines, together with precursors triazenylbenzo[b]thiophenes, were designed, synthesized and screened as anticancer agents. The structural features of these compounds prompted us to investigate their DNA binding capability through UV–vis absorption titrations, circular dichroism, and viscometry, pointing out the occurrence of groove-binding. The derivative 3-(4-methoxy-phenyl)benzothieno[3,2-d]-1,2,3-triazin-4(3H)-one showed the highest antiproliferative effect against HeLa cells and was also tested in cell cycle perturbation experiments. The obtained results assessed for the first time the anticancer activity of benzothieno[3,2-d]-1,2,3-triazine nucleus, and…

Size-exclusion high-performance liquid chromatography in the study of the autoassociating antibiotic gramicidin A in micellar milieu.

2003

Gramicidin A (gA) is a polypeptide antibiotic which forms dimeric channels specific for monovalent cations in biological membranes. It is a polymorphic molecule that adopts several different conformations, double-stranded (ds) helical dimers (pore conformation) and single-stranded beta-helical dimers (channel conformation). This study investigated the conformational adaptability of gramicidin A when incorporated into micelles as membrane-mimetic model system. Taking advantage of our reported, versatile, size-exclusion high-performance liquid chromatography (SE-HPLC) strategy that allows the separation of double-stranded dimers and monomers, we have quantitatively characterized the conformat…

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

2021

The synthesis of a sulfate-modified dendritic peptide amphiphile and its self-assembly into one-dimensional rod-like architectures in aqueous medium is reported. The influence of the ionic strength on the supramolecular polymerization was probed via circular dichroism spectroscopy and cryogenic transmission electron microscopy. Physiological salt concentrations efficiently screen the charges of the dendritic building block equipped with eight sulfate groups and trigger the formation of rigid supramolecular polymers. Since multivalent sulfated supramolecular structures mimic naturally occurring L-selectin ligands, the corresponding affinity was evaluated using a competitive SPR binding assay…

Exploring the binding of Pt drugs to gold nanoparticles for controlled passive release of cisplatin.

2011

Luminescent iminophosphorane gold, palladium and platinum complexes as potential anticancer agents

2014

A series of coordination gold(III), palladium(II), and platinum(II) complexes with a luminescent iminophosphorane ligand derived from 8-aminoquinoline [Ph3P[double bond, length as m-dash]N–C9H6N] (1) have been synthesized and structurally characterized. The coordination palladium(II) and platinum(II) compounds can evolve further, under appropriate conditions, to give stable cyclometalated endo species [M{κ3-C,N,N-C6H4(PPh2[double bond, length as m-dash]N-8-C9H6N)}Cl] (M = Pd, Pt) by C–H activation of the phenyl group of the PPh3 fragment. Iminophosphorane 1 and the new metallic complexes are luminescent in DMSO or DMSO–H2O (1 : 1 mixture) solutions at RT. The compounds have been evaluated f…

Anticancer platinum agents and light

2019

Abstract Since the discovery of cisplatin, light activation has been employed as a strategy to switch and improve the anticancer effects of platinum compounds. This contribution highlights some of the most representative discoveries obtained in the field of platinum-based photochemotherapy over the years.

ChemInform Abstract: Pillar[n]arenes - A Novel, Highly Promising Class of Macrocyclic Host Molecules

2014

Review: [preparation, structure in solution and in the solid state and complexation; 100 refs.

J-MADeM, a market-based model for complex decision problems

2010

This paper presents J-MADeM, a multi-modal decision making mechanism to provide agents in a Multi-Agent Systems (MAS) with a market-based model for complex decision problems. J-MADeM is now available as an open source library fully integrated into Jason, the successful interpreter for the AgentSpeak programming language. The aim of this work is to improve Jason by incorporating an agent decision-making module able to merge multiple information sources received from the rest of the agents. This information is modeled as a set of utility functions expressing the preferences of the agents for a specific problem. Then, J-MADeM agents use one-round sealed-bid combinatorial auctions as the main p…

Tabu search for min-max edge crossing in graphs

2020

Abstract Graph drawing is a key issue in the field of data analysis, given the ever-growing amount of information available today that require the use of automatic tools to represent it. Graph Drawing Problems (GDP) are hard combinatorial problems whose applications have been widely relevant in fields such as social network analysis and project management. While classically in GDPs the main aesthetic concern is related to the minimization of the total sum of crossing in the graph (min-sum), in this paper we focus on a particular variant of the problem, the Min-Max GDP, consisting in the minimization of the maximum crossing among all egdes. Recently proposed in scientific literature, the Min…