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Sample records for 3-dimethylaminobutyl dimethylcarbamate dmabc

  1. Carbamoylcholine analogs as nicotinic acetylcholine receptor agonists--structural modifications of 3-(dimethylamino)butyl dimethylcarbamate (DMABC)

    DEFF Research Database (Denmark)

    Hansen, Camilla Petrycer; Jensen, Anders Asbjørn; Balle, Thomas;

    2009-01-01

    Compounds based on the 3-(dimethylamino)butyl dimethylcarbamate (DMABC) scaffold were synthesized and pharmacologically characterized at the alpha(4)beta(2), alpha(3)beta(4,) alpha(4)beta(4) and alpha(7) neuronal nicotinic acetylcholine receptors (nAChRs). The carbamate functionality and a small...

  2. Exploration of the molecular architecture of the orthosteric binding site in the α4β2 nicotinic acetylcholine receptor with analogs of 3-(dimethylamino)butyl dimethylcarbamate (DMABC) and 1-(pyridin-3-yl)-1,4-diazepane

    DEFF Research Database (Denmark)

    Bach, Tinna Brøbech; Jensen, Anders A.; Petersen, Jette G.;

    2015-01-01

    X-ray crystal structures of acetylcholine binding proteins (AChBPs) have revealed two different possible extensions to the classical ligand binding pocket known to accommodate various nicotinic agonists. One of the pockets is limited in size while the other is of considerable dimensions and protr...

  3. Molecular modeling and anticholinesterasic activity of novel 2-arylaminocyclohexyl N,N-dimethylcarbamates

    Energy Technology Data Exchange (ETDEWEB)

    Bagatin, Mariane C.; Candido, Augusto A.; Basso, Ernani A.; Gauze, Gisele F., E-mail: gfgbandoch@uem.br [Universidade Estadual de Maringa (UEM), PR (Brazil). Departamento de Quimica; Pinheiro, Glaucia M. S.; Hoeehr, Nelci F. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Ciencias Medicas. Departamento de Patologia Clinica; Machinski Junior, Miguel; Mossini, Simone A.G. [Universidade Estadual de Maringa (UEM), PR (Brazil). Departamento de Ciencias Basicas da Saude

    2013-11-15

    This work reports a detailed theoretical and experimental study of the novel isomer series cis- and trans-2-arylaminocyclohexyl N,N-dimethylcarbamates as potential inhibitors of cholinesterases. In vitro inhibition assay by Ellman's method with human blood samples showed that the new carbamates are selective to the inhibition of enzyme butyrylcholinesterase (BuChE) with maximum inhibition of 90% and IC{sub 50} of 6 and 8 mmol L{sup -1} for the more actives compounds of the series. Molecular modeling studies point to significant differences for the conformations of the compounds in the active sites of enzymes BuChE and acetylcholinesterase (AChE). The results show that the compounds interact more effectively with the active site of enzyme BuChE since the carbamate group is close to the key residues of the catalytic triad. (author)

  4. catena-Poly[zinc-tris(μ-dimethylcarbamato-κ2O:O′-zinc-μ-(2-phenylbenzimidazolido-κ2N:N′

    Directory of Open Access Journals (Sweden)

    Mark A. Rodriguez

    2012-01-01

    Full Text Available The crystal structure of the title compound, [Zn2(C13H9N2(C3H6NO23]n, displays a long chiral chain. This is composed of zinc-dimer clusters capped by dimethylcarbamate ligands, which lie on crystallographic twofold rotation axes and are polymerically linked in one dimension by 2-phenylbenzimidadole (2–PBImi organic ligands. The two Zn2+ ions defining the dimetal cluster are crystallographically independent, but display very similar coordination modes and tetrahedral geometry. As such, each Zn2+ ion is coordinated on one side by the N-donor imidazole linker, while the other three available coordination sites are fully occupied by the O atoms from the capping dimethylcarbamates. The chirality of the chain extends along the c axis, generating a rather long 52.470 (11 Å cell axis. Interestingly, the chiral material crystallizes from completely achiral precursors. A twofold axis and 31 screw axis serve to generate the long asymmetric unit.

  5. 3-Oxoisoxazole-2(3H)-carboxamides and isoxazol-3-yl carbamates: Resistance-breaking acetylcholinesterase inhibitors targeting the malaria mosquito, Anopheles gambiae

    Science.gov (United States)

    Verma, Astha; Wong, Dawn M.; Islam, Rafique; Tong, Fan; Ghavami, Maryam; Mutunga, James M.; Slebodnick, Carla; Li, Jianyong; Viayna, Elisabet; Lam, Polo C.-H.; Totrov, Maxim M.; Bloomquist, Jeffrey R.; Carlier, Paul R.

    2015-01-01

    To identify potential selective and resistance-breaking mosquitocides against the African malaria vector Anopheles gambiae, we investigated the acetylcholinesterase (AChE) inhibitory and mosquitocidal properties of isoxazol-3-yl dimethylcarbamates (15), and the corresponding 3-oxoisoxazole-2(3H)-dimethylcarboxamide isomers (14). In both series, compounds were found with excellent contact toxicity to wild-type susceptible (G3) strain and multiply resistant (Akron) strain mosquitoes that carry the G119S resistance mutation of AChE. Compounds possessing good to excellent toxicity to Akron strain mosquitoes inhibit the G119S mutant of An. gambiae AChE (AgAChE) with ki values at least 10- to 600-fold higher than that of propoxur, a compound that does not kill Akron mosquitoes at the highest concentration tested. On average, inactivation of WT AgAChE by dimethylcarboxamides 14 was 10-20 fold faster than that of the corresponding isoxazol-3-yl dimethylcarbamates 15. X-ray crystallography of dimethylcarboxamide 14d provided insight into that reactivity, a finding that may explain the inhibitory power of structurally-related inhibitors of hormone-sensitive lipase. Finally, human/An. gambiae AChE inhibition selectivities of these compounds were low, suggesting the need for additional structural modification. PMID:25684426

  6. Radiotracer Approaches to Carbamate Insecticide Toxicology

    International Nuclear Information System (INIS)

    Methylcarbamates constitute one of the major groups of insecticides. Many unresolved problems in their toxicology may be readily approached with radiotracer studies. Dimethylcarbamates have been prepared with carbonyl-C14-labelling and methylcarbamates withmethyl-, carbonyl-and ring-labelling utilizing carbon-14. The pharmacological action of these.compounds presumably results from acetylcholinesterase inhibition and may involve carbamylation. Reaction of carbonyl- or methyl-labelled carbamates with purified cholinesterase or other esterases would allow a critical examination of this carbamylation reaction and the ease of spontaneous and induced reactivation or decarbamylation. The physiological significance of cholinesterase inhibition might be examined by administering acetate-C14 and analysis for radiolabelled acetylcholine accumulation in nervous tissue, or by utilizing acetyl-C14-choline as the substrate for in vitro determination of the degree of cholinesterase inhibition in tissues of poisoned animals with minimal dilution of the inhibitors and enzymes during analysis. Some progress has been made with radiolabelled materials in investigating the metabolism of carbamate insecticides. Sevin (1-naphthyl methylcarbamate) has been most extensively studied along with its potential hydrolysis products. The assumption that the metabolism of Sevin involves an initial hydrolysis and then further decomposition of the fragments was not supported by carbon-14 studies. The major detoxification mechanism in mammals, and probably also in insects, results from initial oxidative attack on the carbamate by the microsomes in the presence of reduced nicotinamide-adenine dinucleotide phosphate. Sevin is rapidly metabolized in mammals, but the fate of certain of the fragments has not been resolved. Some of the metabolites appear in the milk of lactating animals. One step in the metabolism appears to be formation of the N-methylol derivative. Preliminary studies on the metabolism

  7. Interaction of human butyrylcholinesterase variants with bambuterol and terbutaline.

    Science.gov (United States)

    Kovarik, Zrinka; Simeon-Rudolf, Vera

    2004-04-01

    Bambuterol, a dimethylcarbamate, carbamoylates butyrylcholinesterase (BChE; EC 3.1.1.8). The carbamoylated enzyme is not very stable and the final product of the two-step hydrolysis is a bronchodilator drug, terbutaline (1-(3,5-dihydroxyphenyl)-2-t-butylamino-ethanol sulphate). Both bambuterol and terbutaline inhibit BChE, but their affinities differ in human serum BChE variants (U, A, F, K and S) due to their positive charge. Bambuterol inhibition rate constants for the homozygous usual (UU), Kalow (KK), fluoride-resistant (FF) or atypical (AA) variant ranged from 4.4 to 0.085min (-1)microM(-1). Terbutaline showed competitive reversible inhibition for all BChE variants. The dissociation constants for UU, FF and AA homozygotes were 0.18, 0.31 and 3.3 mM, respectively. The inhibition rate or dissociation constants for heterozygotes were distributed between the respective constants for the corresponding homozygotes. A 50-fold difference in inhibition between the UU and AA enzyme might affect terbutaline release in humans. The affinity of all studied BChE variants for terbutaline was low, which suggests that terbutaline originating from bambuterol hydrolysis should not affect the hydrolysis of bambuterol by BChE. PMID:15449725

  8. "Warning card" as a prevention of prolonged apnea in children.

    Science.gov (United States)

    Lajtman, Z; Surina, B; Bartolek, D; Car, D; Gasparović, S; Kirincić, N; Rudez, J

    2002-12-01

    Human butyrylcholinesterase (EC 3.1.1.8) (BChE) is present in serum mainly as "usual UU" form, but it has also been found in variant forms known as "atypical" BChE. The most important predictive value of BChE phenotype is for anesthetist to prevent prolonged apnea. BChE has an important role in the hydrolysis of neuromuscular relaxant succinylcholine (suxamethonium, scoline) used during anesthesia. In order to detect atypical variants of BChE and give these findings to the anesthetists-surgeons before an operation to avoid the prolonged apnea, we phenotyped 542 sera of children before tonsillectomies. Total BChE activity was measured using butyrylthiocholine as substrate and dibucaine, fluoride, urea and dimethylcarbamate Ro 02-0683 were used as inhibitors. The frequencies of phenotypes in 542 children were: UU, UA, US, SS, AS and AA--92.25%, 7.01%, 0.18%, 0.18%, 0.18%, 0.18% respectively. Once established phenotype of BChE does not change during the lifetime. Therefore the carriers of atypical phenotype of BChE received a "Warning card", which is a permanent warning for succinylcholine application, as well as a sign to the members of the families to test their own phenotype of BChE. In our study three "Warning cards" were given: two to the carriers of atypical phenotype and third to a child presented as SS phenotype with low total activity of BChE. The present study is the first clinical evaluation of this genetic abnormality in the Republic of Croatia. PMID:12674844

  9. Nitrogen-rich higher-molecular soil organic compounds patterned by lignin degradation products: Considerations on the nature of soil organic nitrogen

    Science.gov (United States)

    Liebner, Falk; Bertoli, Luca; Pour, Georg; Klinger, Karl; Ragab, Tamer; Rosenau, Thomas

    2016-04-01

    and NMR spectroscopy (1H, 13C, 15N), respectively. The reactions of hydroquinone, methyl hydroquinone and p-benzoquinone with ammonia and dimethyl-ammonium dimethylcarbamate - a source of dimethyl amine - affording the respective (substituted) 2,5-diamino-[1,4]benzoquinones under aerobic conditions have been studied by EPR spectroscopy for both oxygen-free and oxygen-rich conditions. 15N CPMAS NMR and XPS spectra of ammoxidized technical lignins and of ammoxidized low-molecular polyphenolic and quinoid products of the aerobic, microbial lignin degradation using 15N labeled aqueous ammonium hydroxide share many similarities, highly indicative for reaction sequences proceeding via common key intermediates. It has been demonstrated that 2,5-dihydroxy-[1,4]benzoquinone which can be surprisingly formed from both lignin and cellulose reacts with N nucleophiles to the respective 2,5-amino derivatives. The latter are semi-stable and react further to nitrogenous compounds of higher molecular weight. Hydroquinone and methoxy hydroquinone react even faster affording the respective 2,5-diamino-[1,4]benzoquinones. EPR experiments revealed that the reaction of hydroquinone with dimethyl amine proceed via radical intermediates. The results of this study strongly support the polyphenol theory and is hoped to contribute to a better understanding of nitrogen accumulation in soil organic matter. Acknowledgement The financial support by the Austrian Research Promotion Agency FFG (project FLIPPR: Future Lignin and Pulp Processing Research, 836650) and by The Austrian Science Fund FWF (project I154-N19) is gratefully acknowledged.