82409-02-7Relevant academic research and scientific papers
Synthesis and Antibacterial Activity of a Series of Basic Amides of Teicoplanin and Deglucoteicoplanin with Polyamines
Malabarba, Adriano,Ciabatti, Romeo,Kettenring, Juergen,Scotti, Roberto,Candiani, Gianpaolo,et al.
, p. 4054 - 4060 (1992)
Basic carboxamides of teicoplanin A2 (CTA) and its aglycon (TD) are prepared by condensation of the 63-carboxyl function of these antibiotics with linear or branched polyamines.The antimicrobial activities of some of the resulting compounds were better th
A divergent route towards single-chemical entity triazine dendrimers with opportunities for structural diversity
Crampton, Hannah,Hollink, Emily,Perez, Lisa M.,Simanek, Eric E.
, p. 1283 - 1290 (2007)
This manuscript describes the successful synthesis and characterization of five generations of dendrimers based on melamine. Early generations of these materials appear to be single chemical entities: upon purification, no detectable impurities are observed using NMR spectroscopy, mass spectrometry, and HPLC and GPC analysis. The analysis of larger generation materials precludes an unambiguous statement of purity. The synthetic route to these targets is divergent, relying on dichlorotriazine monomers that react with a polyamine dendrimer core of generation n to produce a poly(monochlorotriazine) dendrimer of generation n + 1. Subsequently, the poly(monochlorotriazine) is derivatized through nucleophilic aromatic substitution before additional nucleophilic amines are unmasked and the process iterated. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Specific targeting of acetylcholinesterase and butyrylcholinesterase recognition sites. Rational design of novel, selective, and highly potent cholinesterase inhibitors
Savini, Luisa,Gaeta, Alessandra,Fattorusso, Caterina,Catalanotti, Bruno,Campiani, Giuseppe,Chiasserini, Luisa,Pellerano, Cesare,Novellino, Ettore,McKissic, Dawn,Saxena, Ashima
, p. 1 - 4 (2003)
Tacrine-based AChE and BuChE inhibitors were designed by investigating the topology of the active site gorge of the two enzymes. The homobivalent ligands characterized by a nitrogen-bridged atom at the tether level could be considered among the most poten
Identification of diamine linkers with differing reactivity and their application in the synthesis of melamine dendrimers
Moreno, Karlos X.,Simanek, Eric E.
, p. 1152 - 1154 (2008)
Diamine linkers for the synthesis of dendrimers based on melamine were identified using competition reactions. The relative reactivity of the surveyed cyclic monoamines varies by 40 times, expanding the previously identified series to an overall relative reactivity range of 320 times. Azetidine is 40 times more reactive than the cyclic, nine-membered ring (C8H17N), and 320 times more reactive than benzylamine. Reactivity differences are attributed to pKa values and sterics. Diamines incorporating these groups are useful linkers that can be employed in dendrimer synthesis. Specifically, the nucleophilicity of the individual amine groups comprising 3-aminoazetidine, 3-aminopyrrolidine, and 4-aminopiperidine varies by 100 times, 70 times, and 20 times, respectively. These linkers are incorporated into a generation three dendrimer.
Design and Solution-Phase Synthesis of Membrane-Targeting Lipopeptides with Selective Antibacterial Activity
Konai, Mohini M.,Adhikary, Utsarga,Haldar, Jayanta
, p. 12853 - 12860 (2017)
Designing selective antibacterial molecules remains an unmet goal in the field of membrane-targeting agents. Herein, we report the rational design and synthesis of a new class of lipopeptides, which possess highly selective bacterial killing over mammalian cells. The selective interaction with bacterial over mammalian membranes was established through various spectroscopic, as well as microscopic experiments, including biophysical studies with the model membranes. A detailed antibacterial structure–activity relationship was delineated after preparing a series of molecules consisting of the peptide moieties with varied sequence of amino acids, such as d-phenylalanine, d-leucine, and d-lysine. Antibacterial activity was found to vary with the nature and positioning of hydrophobicity in the molecules, as well as number of positive charges. Optimized lipopeptide 9 did not show any hemolytic activity even at 1000 μg mL?1 and displayed >200-fold and >100-fold selectivity towards S. aureus and E. coli, respectively. More importantly, compound 9 was found to display good antibacterial activity (MIC 6.3–12.5 μg mL?1) against the five top most critical bacteria according to World Health Organization (WHO) priority pathogens list. Therefore, the results suggested that this new class of lipopeptides bear real promises for the development as future antibacterial agents.
Membrane active phenylalanine conjugated lipophilic norspermidine derivatives with selective antibacterial activity
Konai, Mohini M.,Ghosh, Chandradhish,Yarlagadda, Venkateswarlu,Samaddar, Sandip,Haldar, Jayanta
, p. 9409 - 9423 (2014)
Natural and synthetic membrane active antibacterial agents offer hope as potential solutions to the problem of bacterial resistance as the membrane-active nature imparts low propensity for the development of resistance. In this report norspermidine based antibacterial molecules were developed that displayed excellent antibacterial activity against various wild-type bacteria (Gram-positive and Gram-negative) and drug-resistant bacteria (methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and β-lactam-resistant Klebsiella pneumoniae). In a novel structure-activity relationship study it has been shown how incorporation of an aromatic amino acid drastically improves selective antibacterial activity. Additionally, the effect of stereochemistry on activity, toxicity, and plasma stability has also been studied. These rapidly bactericidal, membrane active antibacterial compounds do not trigger development of resistance in bacteria and hence bear immense potential as therapeutic agents to tackle multidrug resistant bacterial infections.
Synthesis and Relaxometric Characterization of New Poly[N,N-bis(3-aminopropyl)glycine] (PAPGly) Dendrons Gd-Based Contrast Agents and Their in Vivo Study by Using the Dynamic Contrast-Enhanced MRI Technique at Low Field (1 T)
Aime, Silvio,Boutry, Sébastien,Granato, Luigi,Henoumont, Céline,Laurent, Sophie,Longo, Dario,Muller, Robert N.,Vander Elst, Luce
, (2019)
The synthesis of poly[N,N-bis(3-aminopropyl)glycine] (PAPGly) dendrons Gd-based contrast agents (GdCAs) via an orthogonal protection of the different functional groups and an activation/coupling strategy wherein a specific number of synthetic steps add a generation to the existing dendron has been described. The aim of this protocol is to build up two different generations of dendrons (G-0 or dendron's core, and G-1) with peripheral NH2 groups to conjugate a 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) derivative and afterwards to chelate with Gd3+ paramagnetic ions. These complexes, which have a well-defined molecular weight, are of relevance to MRI as an attempt to gain higher 1H relaxivity by slowing down the rotation of molecule compared to monomeric Gd(III) complexes used as contrast agents and to increase the number of paramagnetic centers present in one molecular structure. From the study of their water 1H longitudinal relaxation rate at different magnetic fields (NMRD, Nuclear Magnetic Relaxation Dispersion) and by evaluating the variable temperature 17O-NMR data we determined the parameters characterizing the water exchange rate and the rotational correlation time of each complex, both affecting 1H relaxivity. Furthermore, these two novel PAPGly GdCAs were objects of i) an in vivo study to determine their biodistributions in healthy C57 mice at several time points, and ii) the Dynamic Contrast-Enhanced MRI (DCE-MRI) approach to assess their contrast efficiency measured in the tumor region of C57BL/6 mice transplanted subcutaneously with B16-F10 melanoma cells. The aim of the comparison of these two dendrons GdCAs, having different molecular weights (MW), is to understand how MW and relaxivity may influence the contrast enhancement capabilities in vivo at low magnetic field (1 T). Significant contrast enhancement was observed in several organs (vessel, spleen and liver), already at 5 min post-injection, for the investigated CAs. Moreover, these CAs induced a marked contrast enhancement in the tumor region, thanks to the enhanced permeability retention effect of those macromolecular structures.
Cytotoxicity, hemolysis, and acute in vivo toxicity of dendrimers based on melamine, candidate vehicles for drug delivery
Chen, Hui-Ting,Neerman, Michael F.,Parrish, Alan R.,Simanek, Eric E.
, p. 10044 - 10048 (2004)
A small library of dendrimers was prepared from a common precursor that is available in 5 g scale in five linear steps at 56% overall yield. The precursor is a generation three dendrimer that displays 48 peripheral sites by incorporating AB4 surface groups. Manipulation of these sites provided six dendrimers that vary in the chemistry of the surface group (amine, guanidine, carboxylate, sulfonate, phosphonate, and PEGylated) that were evaluated for hemolytic potential and cytotoxicity. Cationic dendrimers were found to be more cytotoxic and hemolytic than anionic or PEGylated dendrimers. The PEGylated dendrimer was evaluated for acute toxicity in vivo. No toxicity-neither mortality nor abnormal blood chemistry based on blood urea nitrogen levels or alanine transaminase activity-was observed in doses up to 2.56 g/kg ip and 1.28 g/kg iv.
Kilogram-scale synthesis of a second-generation dendrimer based on 1,3,5-triazine using green and industrially compatible methods with a single chromatographic step
Chouai, Abdellatif,Simanek, Eric E.
, p. 2357 - 2366 (2008)
(Figure Presented) A kilogram scale, divergent and iterative synthesis of a second generation, triazine dendrimer with 12 protected amines on the periphery using common laboratory equipment is reported. The route benefits from common reaction conditions, inexpensive reagents, and aqueous solvents. From the monomers, the desired product dendrimer - the last uncommitted intermediate that leads to a range of committed, generation three targets - can be obtained in 70% overall yield. Of critical importance in the execution of this divergent synthesis is the differential reactivity of chlorine atoms of trichlorotriazine. The stepwise, nucleophilic aromatic substitution of these atoms with amine nucleophiles is both the basis for the dendrimer growth as well as incorporation of solubilizing piperidine groups. Intermediates are obtained and purified through precipitation and/or extraction protocols with the exception of the final product. Isolation of the target dendrimer requires a single silica gel plug filtration. The purity of this material is assessed at >93%, a level consistent with and/or exceeding other commercially available targets.
APPLICATION OF MONOCYCLIC BETA-LACTAM COMPOUND IN PHARMACY
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Paragraph 0051, (2021/11/04)
An application of a compound represented by formula (I) and pharmaceutically acceptable salts thereof in preparation of a drug for treating pneumonia.
