153756-98-0Relevant academic research and scientific papers
Synthesis and ligand recognition of paracetamol selective polymers: Semi-covalent versus non-covalent molecular imprinting
Rosengren-Holmberg, Jenny P.,Karlsson, Jesper G.,Svenson, Johan,Andersson, Hakan S.,Nicholls, Ian A.
experimental part, p. 3148 - 3155 (2011/02/25)
Three molecular imprinting strategies, each based upon a series of ethylene glycol dimethacrylate (EGDMA) cross-linked co-polymers, have been used to produce materials selective for the commonly used analgesic and antipyretic agent paracetamol (p-acetaminophen or 4-acetamidophenol) (1). The polymers were synthesised using either a semi-covalent imprinting strategy based upon 4-acetamidophenyl-(4-vinylphenyl) carbonate (4) or a non-covalent strategy based on methacrylic acid (MAA) as the functional monomer, or by employing a combination of these strategies. Radioligand binding studies demonstrated low template affinity in polymers offering only a single electrostatic interaction point for recognition via the phenolic residue in the template, whereas binding was substantially increased upon the introduction of a second binding mode, namely interaction at the acetamide moiety. HPLC analyses revealed no imprinting effect in the purely semi-covalent system, and only a minor effect in the purely non-covalent systems. However, a pronounced imprinting effect was demonstrated for polymers prepared by a combination of semi-covalent and non-covalent imprinting. This study illustrates a limitation of both the non-covalent and the semi-covalent strategies when it comes to achieving imprinted selectivity for small and poorly functionalised templates such as paracetamol. Parallels with conclusions from studies with antibodies are discussed.
CARBONATE PRODRUGS AND METHODS OF USING THE SAME
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Page/Page column 37-38, (2009/12/27)
The present invention provides carbonate prodrugs which comprise a carbonic phosphoric anhydride prodrug moiety attached to the hydroxyl or carboxyl group of a parent drug moiety. The prodrugs may provide improved physicochemical properties over the parent drug. Also provided are methods of treating a disease or condition that is responsive to the parent drug using the carbonate prodrugs, as well as kits and unit dosages.
NOVEL CATHEPSIN C INHIBITORS AND THEIR USE
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Page/Page column 39, (2010/11/23)
The invention is directed to novel cathepsin C inhibitors and their use in the treatment of diseases mediated by the cathepsin C enzyme. Specifically, the invention is directed to compounds according to Formula (I): wherein X and n are defined below, and
Cyclization-Activated Prodrugs: N-(Substituted 2-hydroxyphenyl and 2-hydroxypropyl)carbamates Based on Ring-Opened Derivatives of Active Benzoxazolones and Oxazolidinones as Mutual Prodrugs of Acetaminophen
Vigroux, Alain,Bergon, Michel,Zedde, Chantal
, p. 3983 - 3994 (2007/10/03)
N-(Substituted 2-hydroxyphenyl)- and N-(substituted 2-hydroxypropyl)carbamates based on masked active benzoxazolones (model A) and oxazolidinones (model B), respectively, were synthesized and evaluated as potential drug delivery systems.A series of alkyl and aryl N-(5-chloro-2-hydroxyphenyl)carbamates 1 related to model A was prepared.These are open drugs of the skeletal muscle relaxant chlorzoxazone.The corresponding 4-acetamidophenyl ester named chloracetamol is a mutual prodrug of chloroxazone and acetaminophen.Chlorzacetamol and two other mutual prodrugs of active bezoxazolones and acetaminophen were obtained in a two-step process via condensation of 4-acetamidophenyl 1,2,2,2-tetrachloroethyl carbonate with the appropiate anilines.Based on model B, two mutual prodrugs of acetaminophen and active oxazolidinones (metaxalone and mephenoxalone) were similarly obtained using the appropiate amines.All the carbamate prodrugs prepared were found to release the parent drugs in aqueous (pH 6-11) and plasma (pH 7.4) media.The detailed mechanistic study of prodrugs 1 carried out in aqueous medium at 37 deg C shows a change in the Broensted-type relationship log t1/2 vs pKa of the leaving groups ROH: log t1/2 = 0.46pKa - 3.55 for aryl and trihalogenoethyl esters and log t1/2 = 1.46pKa - 16.03 for alkyl esters.This change is consistent with a cyclization mechanism involving a change in the rate-limiting step from formation of a cyclic tetrahedral intermediate (step k1) to departure of the leaving group ROH (step k2) when the leaving group ability decreases.This mechanism occurs for all the prodrugs related to model A.Regeneration of the parent drugs from mutual prodrugs related to model B takes place by means of a rate-limiting elimination-addition reaction (E1cB mechanism).This affords acetaminophen and the corresponding 2-hydroxypropyl isocyanate intermediates which cyclize at any pH to the corresponding oxazolidinone drugs.As opposed to model A, the rates of hydrolysis of mutual prodrugs of model B clearly exhibit a catalytic role of the plasma.It is concluded from the plasma studies that the carbamate substrates can be enzymatically transformed into potent electrophiles, i.e., isocyanates.In the case of the present study, the prodrugs are 2-hydroxycarbamates for which the propinquity of the hydroxyl residue and the isocyanate group enforces a cyclization reaction.This mechanistic particularity precludes their potential toxicity in terms of potent electrophiles capable of modifying critical macromolecules.
