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Sample records for acid amide hydrolase

  1. Sulfonyl fluoride inhibitors of fatty acid amide hydrolase.

    Alapafuja, Shakiru O; Nikas, Spyros P; Bharathan, Indu T; Shukla, Vidyanand G; Nasr, Mahmoud L; Bowman, Anna L; Zvonok, Nikolai; Li, Jing; Shi, Xiaomeng; Engen, John R; Makriyannis, Alexandros

    2012-11-26

    Sulfonyl fluorides are known to inhibit esterases. Early work from our laboratory has identified hexadecyl sulfonylfluoride (AM374) as a potent in vitro and in vivo inhibitor of fatty acid amide hydrolase (FAAH). We now report on later generation sulfonyl fluoride analogs that exhibit potent and selective inhibition of FAAH. Using recombinant rat and human FAAH, we show that 5-(4-hydroxyphenyl)pentanesulfonyl fluoride (AM3506) has similar inhibitory activity for both the rat and the human enzyme, while rapid dilution assays and mass spectrometry analysis suggest that the compound is a covalent modifier for FAAH and inhibits its action in an irreversible manner. Our SAR results are highlighted by molecular docking of key analogs. PMID:23083016

  2. Defects in fatty acid amide hydrolase 2 in a male with neurologic and psychiatric symptoms

    Sirrs, Sandra; van Karnebeek, Clara DM; Peng, Xiaoxue; Shyr, Casper; Tarailo-Graovac, Maja; Mandal, Rupasri; Testa, Daniel; Dubin, Devin; Carbonetti, Gregory; Glynn, Steven E.; Sayson, Bryan; Robinson, Wendy P.; Han, Beomsoo; Wishart, David; Ross, Colin J

    2015-01-01

    Background Fatty acid amide hydrolase 2 (FAAH2) is a hydrolase that mediates the degradation of endocannabinoids in man. Alterations in the endocannabinoid system are associated with a wide variety of neurologic and psychiatric conditions, but the phenotype and biochemical characterization of patients with genetic defects of FAAH2 activity have not previously been described. We report a male with autistic features with an onset before the age of 2 years who subsequently developed additional f...

  3. Identification of N-acylethanolamines in Dictyostelium discoideum and confirmation of their hydrolysis by fatty acid amide hydrolase[S

    Hayes, Alexander C.; Stupak, Jacek; Li, Jianjun; Cox, Andrew D.

    2013-01-01

    N-acylethanolamines (NAEs) are endogenous lipid-based signaling molecules best known for their role in the endocannabinoid system in mammals, but they are also known to play roles in signaling pathways in plants. The regulation of NAEs in vivo is partly accomplished by the enzyme fatty acid amide hydrolase (FAAH), which hydrolyses NAEs to ethanolamine and their corresponding fatty acid. Inhibition of FAAH has been shown to increase the levels of NAEs in vivo and to produce desirable phenotype...

  4. The role of fatty acid amide hydrolase inhibition in nicotine reward and dependence

    Muldoon, Pretal P.; Lichtman, Aron H.; Parsons, Loren H.; Damaj, M Imad

    2012-01-01

    The endogenous cannabinoid anandamide (AEA) exerts the majority of its effects at CB1 and CB2 receptors and is degraded by fatty acid amide hydrolase (FAAH). FAAH KO mice and animals treated with FAAH inhibitors are impaired in their ability to hydrolyze AEA and other non-cannabinoid lipid signaling molecules, such as oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). AEA and these other substrates activate non- cannabinoid receptor systems, including TRPV1 and PPAR-α receptors. In thi...

  5. Cellular viability effects of fatty acid amide hydrolase inhibition on cerebellar neurons

    Lueneberg Kathia; Domínguez Guadalupe; Arias-Carrión Oscar; Palomero-Rivero Marcela; Millán-Aldaco Diana; Morán. Julio; Drucker-Colín René; Murillo-Rodríguez Eric

    2011-01-01

    Abstract The endocannabinoid anandamide (ANA) participates in the control of cell death inducing the formation of apoptotic bodies and DNA fragmentation. The aim of this study was to evaluate whether the ANA degrading enzyme, the fatty acid amide hydrolase (FAAH), would induce cellular death. Experiments were performed in cerebellar granule neurons cultured with the FAAH inhibitor, URB597 (25, 50 or 100 nM) as well as endogenous lipids such as oleoylethanolamide (OEA) or palmitoylethanolamide...

  6. Phenotypic assessment of THC discriminative stimulus properties in fatty acid amide hydrolase knockout and wildtype mice

    Walentiny, D. Matthew; Vann, Robert E.; Wiley, Jenny L.

    2015-01-01

    A number of studies have examined the ability of the endogenous cannabinoid anandamide to elicit Δ9 -tetrahydrocannabinol (THC)-like subjective effects, as modeled through the THC discrimination paradigm. In the present study, we compared transgenic mice lacking fatty acid amide hydrolase (FAAH), the enzyme primarily responsible for anandamide catabolism, to wildtype counterparts in a THC discrimination procedure. THC (5.6 mg/kg) served as a discriminative stimulus in both genotypes, with sim...

  7. Hemodynamic profile, responsiveness to anandamide, and baroreflex sensitivity of mice lacking fatty acid amide hydrolase

    Pacher, Pál; Bátkai, Sándor; Osei-Hyiaman, Douglas; Offertáler, László; Liu, Jie; Harvey-White, Judy; Brassai, Attila; Járai, Zoltán; Cravatt, Benjamin F.; Kunos, George

    2005-01-01

    The endocannabinoid anandamide exerts neurobehavioral, cardiovascular, and immune-regulatory effects through cannabinoid receptors (CB). Fatty acid amide hydrolase (FAAH) is an enzyme responsible for the in vivo degradation of anandamide. Recent experimental studies have suggested that targeting the endocannabinergic system by FAAH inhibitors is a promising novel approach for the treatment of anxiety, inflammation, and hypertension. In this study, we compared the cardiac performance of FAAH k...

  8. Discovery of MK-3168: A PET Tracer for Imaging Brain Fatty Acid Amide Hydrolase.

    Liu, Ping; Hamill, Terence G; Chioda, Marc; Chobanian, Harry; Fung, Selena; Guo, Yan; Chang, Linda; Bakshi, Raman; Hong, Qingmei; Dellureficio, James; Lin, Linus S; Abbadie, Catherine; Alexander, Jessica; Jin, Hong; Mandala, Suzanne; Shiao, Lin-Lin; Li, Wenping; Sanabria, Sandra; Williams, David; Zeng, Zhizhen; Hajdu, Richard; Jochnowitz, Nina; Rosenbach, Mark; Karanam, Bindhu; Madeira, Maria; Salituro, Gino; Powell, Joyce; Xu, Ling; Terebetski, Jenna L; Leone, Joseph F; Miller, Patricia; Cook, Jacquelynn; Holahan, Marie; Joshi, Aniket; O'Malley, Stacey; Purcell, Mona; Posavec, Diane; Chen, Tsing-Bau; Riffel, Kerry; Williams, Mangay; Hargreaves, Richard; Sullivan, Kathleen A; Nargund, Ravi P; DeVita, Robert J

    2013-06-13

    We report herein the discovery of a fatty acid amide hydrolase (FAAH) positron emission tomography (PET) tracer. Starting from a pyrazole lead, medicinal chemistry efforts directed toward reducing lipophilicity led to the synthesis of a series of imidazole analogues. Compound 6 was chosen for further profiling due to its appropriate physical chemical properties and excellent FAAH inhibition potency across species. [(11)C]-6 (MK-3168) exhibited good brain uptake and FAAH-specific signal in rhesus monkeys and is a suitable PET tracer for imaging FAAH in the brain. PMID:24900701

  9. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  10. Overexpression of fatty acid amide hydrolase induces early flowering in Arabidopsis thaliana

    Neal D. Teaster

    2012-02-01

    Full Text Available N-Acylethanolamines (NAEs are bioactive lipids derived from the hydrolysis of the membrane phospholipid N-acylphosphatidylethanolamine (NAPE. In animal systems this reaction is part of the endocannabinoid signaling pathway, which regulates a variety of physiological processes. The signaling function of NAE is terminated by fatty acid amide hydrolase (FAAH, which hydrolyzes NAE to ethanolamine and free fatty acid. Our previous work in Arabidopsis thaliana showed that overexpression of AtFAAH (At5g64440 lowered endogenous levels of NAEs in seeds, consistent with its role in NAE signal termination. Reduced NAE levels were accompanied by an accelerated growth phenotype, increased sensitivity to abscisic acid (ABA, enhanced susceptibility to bacterial pathogens, and early flowering. Here we investigated the nature of the early flowering phenotype of AtFAAH overexpression. AtFAAH overexpressors flowered several days earlier than wild type and AtFAAH knockouts under both non-inductive short day (SD and inductive long day (LD conditions. Microarray analysis revealed that the FLOWERING LOCUS T (FT gene, which plays a major role in regulating flowering time, and one target MADS box transcription factor, SEPATALLA3 (SEP3, were elevated in AtFAAH overexpressors. Furthermore, AtFAAH overexpressors, with the early flowering phenotype had lower endogenous NAE levels in leaves compared to wild type prior to flowering. Exogenous application of NAE 12:0, which was reduced by up to 30% in AtFAAH overexpressors, delayed the onset of flowering in wild type plants. We conclude that the early flowering phenotype of AtFAAH overexpressors is, in part, explained by elevated FT gene expression resulting from the enhanced NAE hydrolase activity of AtFAAH, suggesting that NAE metabolism may participate in floral signaling pathways.

  11. Fatty acid amide hydrolase (FAAH) inhibition enhances memory acquisition through activation of PPAR-α nuclear receptors

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil

    2009-01-01

    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB1-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for α-type peroxisome proliferator-activated nuclear receptors, PPAR-α) when and where they are naturally released in the brain. Using a passive-avoidance task in rats, we found that memory acquisition was enhanced by the FAAH inhibitor URB597 or by the PPAR-α agonist WY14643, and these enhancements ...

  12. Inhibitors of Fatty Acid Amide Hydrolase and Monoacylglycerol Lipase: New Targets for Future Antidepressants.

    Ogawa, Shintaro; Kunugi, Hiroshi

    2015-01-01

    Cannabis and analogs of Δ9-tetrahydrocannabinol have been used for therapeutic purposes, but their therapeutic use remains limited because of various adverse effects. Endogenous cannabinoids have been discovered, and dysregulation of endocannabinoid signaling is implicated in the pathophysiology of major depressive disorder (MDD). Recently, endocannabinoid hydrolytic enzymes such as fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) have become new therapeutic targets in the treatment of MDD. Several FAAH or MAGL inhibitors are reported to have no cannabimimetic side effects and, therefore, are new potential therapeutic options for patients with MDD who are resistant to first-line antidepressants (selective serotonin and serotonin-norepinephrine reuptake inhibitors). In this review, we focus on the possible relationships between MDD and the endocannabinoid system as well as the inhibitors' therapeutic potential. MAGL inhibitors may reduce inflammatory responses through activation of cannabinoid receptor type 2. In the hypothalamic-pituitary-adrenal axis, repeated FAAH inhibitor administration may be beneficial for reducing circulating glucocorticoid levels. Both FAAH and MAGL inhibitors may contribute to dopaminergic system regulation. Recently, several new inhibitors have been developed with strong potency and selectivity. FAAH inhibitor, MAGL inhibitor, or dual blocker use would be promising new treatments for MDD. Further pre-clinical studies and clinical trials using these inhibitors are warranted. PMID:26630956

  13. A pro-nociceptive phenotype unmasked in mice lacking fatty-acid amide hydrolase.

    Carey, Lawrence M; Slivicki, Richard A; Leishman, Emma; Cornett, Ben; Mackie, Ken; Bradshaw, Heather; Hohmann, Andrea G

    2016-02-01

    Fatty-acid amide hydrolase (FAAH) is the major enzyme responsible for degradation of anandamide, an endocannabinoid. Pharmacological inhibition or genetic deletion of FAAH (FAAH KO) produces antinociception in preclinical pain models that is largely attributed to anandamide-induced activation of cannabinoid receptors. However, FAAH metabolizes a wide range of structurally related, biologically active lipid signaling molecules whose functions remain largely unknown. Some of these endogenous lipids, including anandamide itself, may exert pro-nociceptive effects under certain conditions. In our study, FAAH KO mice exhibited a characteristic analgesic phenotype in the tail flick test and in both formalin and carrageenan models of inflammatory nociception. Nonetheless, intradermal injection of the transient receptor potential channel V1 (TRPV1) agonist capsaicin increased nocifensive behavior as well as mechanical and heat hypersensitivity in FAAH KO relative to wild-type mice. This pro-nociceptive phenotype was accompanied by increases in capsaicin-evoked Fos-like immunoreactive (FLI) cells in spinal dorsal horn regions implicated in nociceptive processing and was attenuated by CB1 (AM251) and TRPV1 (AMG9810) antagonists. When central sensitization was established, FAAH KO mice displayed elevated levels of anandamide, other fatty-acid amides, and endogenous TRPV1 agonists in both paw skin and lumbar spinal cord relative to wild-type mice. Capsaicin decreased spinal cord 2-AG levels and increased arachidonic acid and prostaglandin E2 levels in both spinal cord and paw skin irrespective of genotype. Our studies identify a previously unrecognized pro-nociceptive phenotype in FAAH KO mice that was unmasked by capsaicin challenge. The heightened nociceptive response was mediated by CB1 and TRPV1 receptors and accompanied by enhanced spinal neuronal activation. Moreover, genetic deletion of FAAH has a profound impact on the peripheral and central lipidome. Thus, genetic

  14. Discovery of a Potent, Selective, and Efficacious Class of Reversible α-Ketoheterocycle Inhibitors of Fatty Acid Amide Hydrolase Effective as Analgesicsa

    Boger, Dale L.; Miyauchi, Hiroshi; Du, Wu; Hardouin, Christophe; Fecik, Robert A.; Cheng, Heng; Hwang, Inkyu; Hedrick, Michael P.; Leung, Donmienne; Acevedo, Orlando; Guimarães, Cristiano R. W.; Jorgensen, William L.; Cravatt, Benjamin F.

    2005-01-01

    Fatty acid amide hydrolase (FAAH) degrades neuromodulating fatty acid amides including anandamide (endogenous cannabinoid agonist) and oleamide (sleep-inducing lipid) at their sites of action and is intimately involved in their regulation. Herein we report the discovery of a potent, selective, and efficacious class of reversible FAAH inhibitors that produce analgesia in animal models validating a new therapeutic target for pain intervention. Key to the useful inhibitor discovery was the routi...

  15. Oxygenated metabolites of anandamide and 2-arachidonoylglycerol : conformational analysis and interaction with cannabinoid receptors, membrane transporter, and fatty acid amide hydrolase

    Vliegenthart, J.F.G.; Stelt, M. van der; Kuik, J.A. van; Zadelhoff, G. van; Leeflang, B.R.; Veldink, G.A.; Finazzi Agrò, A.; Maccarrone, M.

    2002-01-01

    This study was aimed at finding structural requirements for the interaction of the acyl chain of endocannabinoids with cannabinoid receptors, membrane transporter protein, and fatty acid amide hydrolase (FAAH). To this end, the flexibility of the acyl chain was restricted by introduction of an 1-hyd

  16. Intracellular Self-Assembly of Cyclic d-Luciferin Nanoparticles for Persistent Bioluminescence Imaging of Fatty Acid Amide Hydrolase.

    Yuan, Yue; Wang, Fuqiang; Tang, Wei; Ding, Zhanling; Wang, Lin; Liang, Lili; Zheng, Zhen; Zhang, Huafeng; Liang, Gaolin

    2016-07-26

    Fatty acid amide hydrolase (FAAH) overexpression induces several disorder symptoms in nerve systems, and therefore long-term tracing of FAAH activity in vivo is of high importance but remains challenging. Current bioluminescence (BL) methods are limited in detecting FAAH activity within 5 h. Herein, by rational design of a latent BL probe (d-Cys-Lys-CBT)2 (1), we developed a "smart" method of intracellular reduction-controlled self-assembly and FAAH-directed disassembly of its cyclic d-luciferin-based nanoparticles (i.e., 1-NPs) for persistent BL imaging of FAAH activity in vitro, in cells, and in vivo. Using aminoluciferin methyl amide (AMA), Lys-amino-d-luciferin (Lys-Luc), and amino-d-luciferin (NH2-Luc) as control BL probes, we validated that the persistent BL of 1 from luciferase-expressing cells or tumors was controlled by the activity of intracellular FAAH. With the property of long-term tracing of FAAH activity in vivo of 1, we envision that our BL precursor 1 could probably be applied for in vivo screening of FAAH inhibitors and the diagnosis of their related diseases (or disorders) in the future. PMID:27348334

  17. Physical Nature of Fatty Acid Amide Hydrolase Interactions with Its Inhibitors: Testing a Simple Nonempirical Scoring Model.

    Giedroyć-Piasecka, Wiktoria; Dyguda-Kazimierowicz, Edyta; Beker, Wiktor; Mor, Marco; Lodola, Alessio; Sokalski, W Andrzej

    2014-12-26

    Fatty acid amide hydrolase (FAAH) is an enzyme responsible for the deactivating hydrolysis of fatty acid ethanolamide neuromodulators. FAAH inhibitors have gained considerable interest due to their possible application in the treatment of anxiety, inflammation, and pain. In the context of inhibitor design, the availability of reliable computational tools for predicting binding affinity is still a challenging task, and it is now well understood that empirical scoring functions have several limitations that in principle could be overcome by quantum mechanics. Herein, systematic ab initio analyses of FAAH interactions with a series of inhibitors belonging to the class of the N-alkylcarbamic acid aryl esters have been performed. In contrast to our earlier studies of other classes of enzyme-inhibitor complexes, reasonable correlation with experimental results required us to consider correlation effects along with electrostatic term. Therefore, the simplest comprehensive nonempirical model allowing for qualitative predictions of binding affinities for FAAH ligands consists of electrostatic multipole and second-order dispersion terms. Such a model has been validated against the relative stabilities of the benchmark S66 set of biomolecular complexes. As it does not involve parameters fitted to experimentally derived data, this model offers a unique opportunity for generally applicable inhibitor design and virtual screening. PMID:25420234

  18. Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context

    Laura Bindila; Antoni Pastor; Margarita Pérez-Martín; Rafael De La Torre; Juan Suarez

    2015-01-01

    Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3+ or BrdU+ cells) of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3+), astroglia (GFAP+), and microglia (Iba1+ cells) were analyzed in the hippocampus, hypothalamus and striatum o...

  19. Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context.

    Rivera, Patricia; Bindila, Laura; Pastor, Antoni; Pérez-Martín, Margarita; Pavón, Francisco J.; Serrano, Antonia; de la Torre, Rafael; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3(+) or BrdU(+) cells) of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3(+)), astroglia (GFAP(+)), and microglia (Iba1(+) cells) were analyzed in the hippocampus, hypothalamus and ...

  20. Inhibitors of monoacylglycerol lipase, fatty-acid amide hydrolase and endocannabinoid transport differentially suppress capsaicin-induced behavioral sensitization through peripheral endocannabinoid mechanisms

    Spradley, Jessica M.; Guindon, Josée; Hohmann, Andrea G.

    2010-01-01

    Monoacylglycerol lipase (MGL) and fatty acid amide hydrolase (FAAH) degrade the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA), respectively. Pharmacological inhibition of these enzymes in the periphery may elucidate the role of endocannabinoids in controlling nociceptive transmission. We compared effects of the MGL inhibitor JZL184, the FAAH inhibitor URB597, and the endocannabinoid uptake inhibitor VDM11, administered locally in the paw, on behavioral hypersensitivities...

  1. Dysfunction in fatty acid amide hydrolase is associated with depressive-like behavior in Wistar Kyoto rats.

    K Yaragudri Vinod

    Full Text Available BACKGROUND: While the etiology of depression is not clearly understood at the present time, this mental disorder is thought be a complex and multifactorial trait with important genetic and environmental contributing factors. METHODOLOGY/PRINCIPAL FINDINGS: The role of the endocannabinoid (eCB system in depressive behavior was examined in Wistar Kyoto (WKY rat strain, a genetic model of depression. Our findings revealed selective abnormalities in the eCB system in the brains of WKY rats compared to Wistar (WIS rats. Immunoblot analysis indicated significantly higher levels of fatty acid amide hydrolase (FAAH in frontal cortex and hippocampus of WKY rats with no alteration in the level of N-arachidonyl phosphatidyl ethanolamine specific phospholipase-D (NAPE-PLD. Significantly higher levels of CB1 receptor-mediated G-protein coupling and lower levels of anandamide (AEA were found in frontal cortex and hippocampus of WKY rats. While the levels of brain derived neurotropic factor (BDNF were significantly lower in frontal cortex and hippocampus of WKY rats compared to WIS rats, pharmacological inhibition of FAAH elevated BDNF levels in WKY rats. Inhibition of FAAH enzyme also significantly increased sucrose consumption and decreased immobility in the forced swim test in WKY rats. CONCLUSIONS/SIGNIFICANCE: These findings suggest a critical role for the eCB system and BDNF in the genetic predisposition to depressive-like behavior in WKY rats and point to the potential therapeutic utility of eCB enhancing agents in depressive disorder.

  2. Effect of cannabidiol on sepsis-induced motility disturbances in mice: involvement of CB receptors and fatty acid amide hydrolase.

    de Filippis, D; Iuvone, T; d'amico, A; Esposito, G; Steardo, L; Herman, A G; Pelckmans, P A; de Winter, B Y; de Man, J G

    2008-08-01

    Sepsis is an inflammatory condition that is associated with reduced propulsive gastrointestinal motility (ileus). A therapeutic option to treat sepsis is to promote intestinal propulsion preventing bacterial stasis, overgrowth and translocation. Recent evidence suggests that anti-oxidants improve sepsis-induced ileus. Cannabidiol, a non-psychotropic component of Cannabis sativa, exerts strong anti-oxidant and anti-inflammatory effects without binding to cannabinoid CB(1) or CB(2) receptors. Cannabidiol also regulates the activity of fatty acid amide hydrolase (FAAH) which is the main enzyme involved in endocannabinoid breakdown and which modulates gastrointestinal motility. Because of the therapeutic potential of cannabidiol in several pathologies, we investigated its effect on sepsis-induced ileus and on cannabinoid receptor and FAAH expression in the mouse intestine. Sepsis was induced by treating mice with lipopolysaccharides for 18 h. Sepsis led to a decrease in gastric emptying and intestinal transit. Cannabidiol further reduced gastrointestinal motility in septic mice but did not affect gastrointestinal motility in control mice. A low concentration of the CB(1) antagonist AM251 did not affect gastrointestinal motility in control mice but reversed the effect of cannabidiol in septic mice. Sepsis was associated with a selective upregulation of intestinal CB(1) receptors without affecting CB(2) receptor expression and with increased FAAH expression. The increase in FAAH expression was completely reversed by cannabidiol but not affected by AM251. Our results show that sepsis leads to an imbalance of the endocannabinoid system in the mouse intestine. Despite its proven anti-oxidant and anti-inflammatory properties, cannabidiol may be of limited use for the treatment of sepsis-induced ileus. PMID:18373655

  3. Fatty acid amide hydrolase-dependent generation of antinociceptive drug metabolites acting on TRPV1 in the brain.

    David A Barrière

    Full Text Available The discovery that paracetamol is metabolized to the potent TRPV1 activator N-(4-hydroxyphenyl-5Z,8Z,11Z,14Z-eicosatetraenamide (AM404 and that this metabolite contributes to paracetamol's antinociceptive effect in rodents via activation of TRPV1 in the central nervous system (CNS has provided a potential strategy for developing novel analgesics. Here we validated this strategy by examining the metabolism and antinociceptive activity of the de-acetylated paracetamol metabolite 4-aminophenol and 4-hydroxy-3-methoxybenzylamine (HMBA, both of which may undergo a fatty acid amide hydrolase (FAAH-dependent biotransformation to potent TRPV1 activators in the brain. Systemic administration of 4-aminophenol and HMBA led to a dose-dependent formation of AM404 plus N-(4-hydroxyphenyl-9Z-octadecenamide (HPODA and arvanil plus olvanil in the mouse brain, respectively. The order of potency of these lipid metabolites as TRPV1 activators was arvanil = olvanil>>AM404> HPODA. Both 4-aminophenol and HMBA displayed antinociceptive activity in various rodent pain tests. The formation of AM404, arvanil and olvanil, but not HPODA, and the antinociceptive effects of 4-aminophenol and HMBA were substantially reduced or disappeared in FAAH null mice. The activity of 4-aminophenol in the mouse formalin, von Frey and tail immersion tests was also lost in TRPV1 null mice. Intracerebroventricular injection of the TRPV1 blocker capsazepine eliminated the antinociceptive effects of 4-aminophenol and HMBA in the mouse formalin test. In the rat, pharmacological inhibition of FAAH, TRPV1, cannabinoid CB1 receptors and spinal 5-HT3 or 5-HT1A receptors, and chemical deletion of bulbospinal serotonergic pathways prevented the antinociceptive action of 4-aminophenol. Thus, the pharmacological profile of 4-aminophenol was identical to that previously reported for paracetamol, supporting our suggestion that this drug metabolite contributes to paracetamol's analgesic activity via

  4. Fatty Acid Amide Hydrolase-Dependent Generation of Antinociceptive Drug Metabolites Acting on TRPV1 in the Brain

    Blomgren, Anders; Simonsen, Charlotte; Daulhac, Laurence; Libert, Frédéric; Chapuy, Eric; Etienne, Monique; Högestätt, Edward D.; Zygmunt, Peter M.; Eschalier, Alain

    2013-01-01

    The discovery that paracetamol is metabolized to the potent TRPV1 activator N-(4-hydroxyphenyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (AM404) and that this metabolite contributes to paracetamol’s antinociceptive effect in rodents via activation of TRPV1 in the central nervous system (CNS) has provided a potential strategy for developing novel analgesics. Here we validated this strategy by examining the metabolism and antinociceptive activity of the de-acetylated paracetamol metabolite 4-aminophenol and 4-hydroxy-3-methoxybenzylamine (HMBA), both of which may undergo a fatty acid amide hydrolase (FAAH)-dependent biotransformation to potent TRPV1 activators in the brain. Systemic administration of 4-aminophenol and HMBA led to a dose-dependent formation of AM404 plus N-(4-hydroxyphenyl)-9Z-octadecenamide (HPODA) and arvanil plus olvanil in the mouse brain, respectively. The order of potency of these lipid metabolites as TRPV1 activators was arvanil = olvanil>>AM404> HPODA. Both 4-aminophenol and HMBA displayed antinociceptive activity in various rodent pain tests. The formation of AM404, arvanil and olvanil, but not HPODA, and the antinociceptive effects of 4-aminophenol and HMBA were substantially reduced or disappeared in FAAH null mice. The activity of 4-aminophenol in the mouse formalin, von Frey and tail immersion tests was also lost in TRPV1 null mice. Intracerebroventricular injection of the TRPV1 blocker capsazepine eliminated the antinociceptive effects of 4-aminophenol and HMBA in the mouse formalin test. In the rat, pharmacological inhibition of FAAH, TRPV1, cannabinoid CB1 receptors and spinal 5-HT3 or 5-HT1A receptors, and chemical deletion of bulbospinal serotonergic pathways prevented the antinociceptive action of 4-aminophenol. Thus, the pharmacological profile of 4-aminophenol was identical to that previously reported for paracetamol, supporting our suggestion that this drug metabolite contributes to paracetamol’s analgesic activity via activation

  5. Synthesis and preclinical evaluation of [11C-carbonyl]PF-04457845 for neuroimaging of fatty acid amide hydrolase

    Introduction: Fatty acid amide hydrolase (FAAH) has a significant role in regulating endocannabinoid signaling in the central nervous system. As such, FAAH inhibitors are being actively sought for pain, addiction, and other indications. This has led to the recent pursuit of positron emission tomography (PET) radiotracers targeting FAAH. We report herein the preparation and preclinical evaluation of [11C-carbonyl]PF-04457845, an isotopologue of the potent irreversible FAAH inhibitor. Methods: PF-04457845 was radiolabeled at the carbonyl position via automated [11C]CO2-fixation. Ex vivo brain biodistribution of [11C-carbonyl]PF-04457845 was carried out in conscious rats. Specificity was determined by pre-administration of PF-04457845 or URB597 prior to [11C-carbonyl]PF-04457845. In a separate experiment, rats injected with the title radiotracer had whole brains excised, homogenized and extracted to examine irreversible binding to brain parenchyma. Results: The title compound was prepared in 5 ± 1% (n = 4) isolated radiochemical yield based on starting [11C]CO2 (decay uncorrected) within 25 min from end-of-bombardment in > 98% radiochemical purity and a specific activity of 73.5 ± 8.2 GBq/μmol at end-of-synthesis. Uptake of [11C-carbonyl]PF-04457845 into the rat brain was high (range of 1.2–4.4 SUV), heterogeneous, and in accordance with reported FAAH distribution. Saturable binding was demonstrated by a dose-dependent reduction in brain radioactivity uptake following pre-treatment with PF-04457845. Pre-treatment with the prototypical FAAH inhibitor, URB597, reduced the brain radiotracer uptake in all regions by 71–81%, demonstrating specificity for FAAH. The binding of [11C-carbonyl]PF-04457845 to FAAH at 40 min post injection was irreversible as 98% of the radioactivity in the brain could not be extracted. Conclusions: [11C-carbonyl]PF-04457845 was rapidly synthesized via an automated radiosynthesis. Ex vivo biodistribution studies in conscious rodents

  6. [{sup 11}C]CURB: Evaluation of a novel radiotracer for imaging fatty acid amide hydrolase by positron emission tomography

    Wilson, Alan A., E-mail: alan.wilson@camhpet.c [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Garcia, Armando; Parkes, Jun [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Houle, Sylvain [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Tong, Junchao [Department of Psychiatry, University of Toronto, Toronto, Ontario, M5T 1R8 (Canada); Vasdev, Neil [PET Centre, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada); Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, M5T 1R8 (Canada)

    2011-02-15

    Introduction: Fatty acid amide hydrolase (FAAH) is the enzyme responsible for metabolising the endogenous cannabinoid, anandamide, and thus represents an important target for molecular imaging. To date, no radiotracer has been shown to be useful for imaging of FAAH using either positron emission tomography (PET) or single photon emission computed tomography (SPECT). We here determine the suitability of a novel carbon-11-labeled inhibitor of FAAH via ex vivo biodistribution studies in rat brain in conjunction with pharmacological challenges. Methods: A potent irreversible inhibitor of FAAH, URB694, radiolabeled with carbon-11 in the carbonyl position ([{sup 11}C]CURB), was administered to male rats via tail-vein injection. Rats were sacrificed at various time points postinjection, and tissue samples were dissected, counted and weighed. Specific binding to FAAH was investigated by pretreatment of animals with URB694 or URB597. For metabolism and mechanism of binding studies, whole brains were excised post-radiotracer injection, homogenised and extracted exhaustively with 80% aq. acetonitrile to determine the time course and fraction of radioactivity that was irreversibly bound to brain parenchyma. Results: Upon intravenous injection into rats, [{sup 11}C]CURB showed high brain uptake [standard uptake value (SUV) of 1.6-2.4 at 5 min] with little washout over time, which is characteristic of irreversible binding. Highest uptake of radioactivity was seen in the cortex, intermediate in the cerebellum and lowest in the hypothalamus, reflecting the reported distribution of FAAH. Brain uptake of radioactivity was decreased in a dose-dependent manner by pretreatment with increasing amounts of URB694, demonstrating that binding was saturable. Pretreatment with the well-characterised FAAH inhibitor, URB597, reduced binding in all brain regions by 70-80%. Homogenised brain extraction experiments demonstrated unequivocally that [{sup 11}C]CURB was irreversibly bound to FAAH

  7. [11C]CURB: Evaluation of a novel radiotracer for imaging fatty acid amide hydrolase by positron emission tomography

    Introduction: Fatty acid amide hydrolase (FAAH) is the enzyme responsible for metabolising the endogenous cannabinoid, anandamide, and thus represents an important target for molecular imaging. To date, no radiotracer has been shown to be useful for imaging of FAAH using either positron emission tomography (PET) or single photon emission computed tomography (SPECT). We here determine the suitability of a novel carbon-11-labeled inhibitor of FAAH via ex vivo biodistribution studies in rat brain in conjunction with pharmacological challenges. Methods: A potent irreversible inhibitor of FAAH, URB694, radiolabeled with carbon-11 in the carbonyl position ([11C]CURB), was administered to male rats via tail-vein injection. Rats were sacrificed at various time points postinjection, and tissue samples were dissected, counted and weighed. Specific binding to FAAH was investigated by pretreatment of animals with URB694 or URB597. For metabolism and mechanism of binding studies, whole brains were excised post-radiotracer injection, homogenised and extracted exhaustively with 80% aq. acetonitrile to determine the time course and fraction of radioactivity that was irreversibly bound to brain parenchyma. Results: Upon intravenous injection into rats, [11C]CURB showed high brain uptake [standard uptake value (SUV) of 1.6-2.4 at 5 min] with little washout over time, which is characteristic of irreversible binding. Highest uptake of radioactivity was seen in the cortex, intermediate in the cerebellum and lowest in the hypothalamus, reflecting the reported distribution of FAAH. Brain uptake of radioactivity was decreased in a dose-dependent manner by pretreatment with increasing amounts of URB694, demonstrating that binding was saturable. Pretreatment with the well-characterised FAAH inhibitor, URB597, reduced binding in all brain regions by 70-80%. Homogenised brain extraction experiments demonstrated unequivocally that [11C]CURB was irreversibly bound to FAAH. Conclusions: The

  8. The synthesis and in vivo evaluation of [18F]PF-9811: a novel PET ligand for imaging brain fatty acid amide hydrolase (FAAH)

    Introduction: Fatty acid amide hydrolase (FAAH) is responsible for the enzymatic degradation of the fatty acid amide family of signaling lipids, including the endogenous cannabinoid (endocannabinoid) anandamide. The involvement of the endocannabinoid system in pain and other nervous system disorders has made FAAH an attractive target for drug development. Companion molecular imaging probes are needed, however, to assess FAAH inhibition in the nervous system in vivo. We report here the synthesis and in vivo evaluation of [18F]PF-9811, a novel PET ligand for non-invasive imaging of FAAH in the brain. Methods: The potency and selectivity of unlabeled PF-9811 were determined by activity-based protein profiling (ABPP) both in vitro and in vivo. [18F]PF-9811 was synthesized in a 3-step, one-pot reaction sequence, followed by HPLC purification. Biological evaluation was performed by biodistribution and dynamic PET imaging studies in male rats. The specificity of [18F]PF-9811 uptake was evaluated by pre-administration of PF-04457845, a potent and selective FAAH inhibitor, 1 h prior to radiotracer injection. Results: Biodistribution studies show good uptake (SUV ∼ 0.8 at 90 min) of [18F]PF-9811 in rat brain, with significant reduction of the radiotracer in all brain regions (37%–73% at 90 min) in blocking experiments. Dynamic PET imaging experiments in rat confirmed the heterogeneous uptake of [18F]PF-9811 in brain regions with high FAAH enzymatic activity, as well as statistically significant reductions in signal following pre-administration of the blocking compound PF-04457845. Conclusions: [18F]PF-9811 is a promising PET imaging agent for FAAH. Biodistribution and PET imaging experiments show that the tracer has good uptake in brain, regional heterogeneity, and specific binding as determined by blocking experiments with the highly potent and selective FAAH inhibitor, PF-04457845.

  9. Effects of fatty acid amide hydrolase inhibition on neuronal responses to nicotine, cocaine and morphine in the nucleus accumbens shell and ventral tegmental area: involvement of PPAR-α nuclear receptors

    Luchicchi, Antonio; Lecca, Salvatore; Carta, Stefano; Pillolla, Giuliano; Muntoni, Anna Lisa; Yasar, Sevil; Goldberg, Steven R.; Pistis, Marco

    2010-01-01

    The endocannabinoid system regulates neurotransmission in brain regions relevant to neurobiological and behavioral actions of addicting drugs. We recently demonstrated that inhibition by URB597 of fatty acid amide hydrolase (FAAH), the main enzyme which degrades the endogenous cannabinoid N-acylethanolamine (NAE) anandamide and the endogenous non-cannabinoid NAEs oleoylethanolamide and palmitoylethanolamide, blocks nicotine-induced excitation of ventral tegmental area (VTA) dopamine (DA) neur...

  10. Pharmacological blockade of the fatty acid amide hydrolase (FAAH) alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context.

    Rivera, Patricia; Bindila, Laura; Pastor, Antoni; Pérez-Martín, Margarita; Pavón, Francisco J; Serrano, Antonia; de la Torre, Rafael; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH) inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3(+) or BrdU(+) cells) of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3(+)), astroglia (GFAP(+)), and microglia (Iba1(+) cells) were analyzed in the hippocampus, hypothalamus and striatum of rats intraperitoneally treated with URB597 (0.3 mg/kg/day) at one dose/4-days resting or 5 doses (1 dose/day). Repeated URB597 treatment increased the plasma levels of the N-acylethanolamines oleoylethanolamide, palmitoylethanolamide and arachidonoylethanolamine, reduced the plasma levels of glucose, triglycerides and cholesterol, and induced a transitory body weight decrease. The hippocampi of repeated URB597-treated rats showed a reduced number of phospho-H3(+) and BrdU(+) subgranular cells as well as GFAP(+), Iba1(+) and cleaved caspase-3(+) cells, which was accompanied with decreased hippocampal expression of the cannabinoid CB1 receptor gene Cnr1 and Faah. In the hypothalami of these rats, the number of phospho-H3(+), GFAP(+) and 3-weeks-old BrdU(+) cells was specifically decreased. The reduced striatal expression of CB1 receptor in repeated URB597-treated rats was only associated with a reduced apoptosis. In contrast, the striatum of acute URB597-treated rats showed an increased number of subventricular proliferative, astroglial and apoptotic cells, which was accompanied with increased Faah expression. Main results indicated that FAAH inhibitor URB597 decreased neural proliferation, glia and apoptosis in a brain region-dependent manner, which were coupled to local changes in Faah and/or Cnr1 expression and a negative energy context. PMID:25870539

  11. PET imaging of fatty acid amide hydrolase in the brain: synthesis and biological evaluation of an 11C-labelled URB597 analogue

    Introduction: Fatty acid amide hydrolase (FAAH) is part of the endocannabinoid system (ECS) and has been linked to the aetiology of several neurological and neuropsychiatric disorders. So far no useful PET or SPECT tracer for in vivo visualisation of FAAH has been reported. We synthesized and evaluated a carbon-11-labeled URB597 analogue, biphenyl-3-yl [11C]-4-methoxyphenylcarbamate or [11C]-1, as potential FAAH imaging agent. Methods: The inhibitory activity of 1 was determined in vitro using recombinant FAAH. Radiosynthesis of [11C]-1 was performed by methylation using [11C]-CH3I, followed by HPLC purification. Biological evaluation was done by biodistribution studies in wild-type and FAAH knock-out mice, and by ex vivo and in vivo metabolite analysis. The influence of URB597 pretreatment on the metabolisation profile was assessed. Results: [11C]-1 was obtained in good yields and high radiochemical purity. Biodistribution studies revealed high brain uptake in wild-type and FAAH knock-out mice, but no retention of radioactivity could be demonstrated. Metabolite analysis and URB597 pretreatment confirmed the non-FAAH-mediated metabolisation of [11C]-1. The inhibition mechanism was determined to be reversible. In addition, the inhibition of URB597 appeared slowly reversible. Conclusions: Although [11C]-1 inhibits FAAH in vitro and displays high brain uptake, the inhibition mechanism seems to deviate from the proposed carbamylation mechanism. Consequently, it does not covalently bind to FAAH and will not be useful for mapping the enzyme in vivo. However, it represents a potential starting point for the development of in vivo FAAH imaging tools.

  12. Pharmacological blockade of the fatty acid amide hydrolase (FAAH alters neural proliferation, apoptosis and gliosis in the rat hippocampus, hypothalamus and striatum in a negative energy context

    Patricia eRivera

    2015-03-01

    Full Text Available Endocannabinoids participate in the control of neurogenesis, neural cell death and gliosis. The pharmacological effect of the fatty acid amide hydrolase (FAAH inhibitor URB597, which limits the endocannabinoid degradation, was investigated in the present study. Cell proliferation (phospho-H3+ or BrdU+ cells of the main adult neurogenic zones as well as apoptosis (cleaved caspase-3+, astroglia (GFAP+, and microglia (Iba1+ cells were analyzed in the hippocampus, hypothalamus and striatum of rats intraperitoneally treated with URB597 (0.3 mg/kg/day at one dose/4-days resting or 5 doses (1 dose/day. Repeated URB597 treatment increased the plasma levels of the endocannabinoids oleoylethanolamide, palmitoylethanolamide and arachidonoylethanolamine, reduced the plasma levels of glucose, triglycerides and cholesterol, and induced a transitory body weight decrease. The hippocampi of repeated URB597-treated rats showed a reduced number of phospho-H3+ and BrdU+ subgranular cells as well as GFAP+, Iba1+ and cleaved caspase-3+ cells, which was accompanied with decreased hippocampal expressions of cannabinoid CB1 receptor and FAAH. In the hypothalami of these rats, the number of phospho-H3+, GFAP+ and 3-weeks-old BrdU+ cells was specifically decreased. The reduced striatal expression of CB1 receptor in repeated URB597-treated rats was only associated with a reduced apoptosis. In contrast, the striatum of acute URB597-treated rats showed an increased number of subventricular proliferative, astroglial and apoptotic cells, which was accompanied with increased Faah expression. Main results indicated that FAAH inhibitor URB597 decreased neural proliferation, glia and apoptosis in a brain region-dependent manner, which were coupled to local changes in FAAH and/or CB1 receptor expressions and a negative energy context.

  13. Lipopolysaccharide-induced pulmonary inflammation is not accompanied by a release of anandamide into the lavage fluid or a down-regulation of the activity of fatty acid amide hydrolase

    Holt, S.; J. Fowler, C.; Rocksén, D.; Bucht, A.; Petersen, G.; Hansen, Harald S.; Valenti, M.; Di Marzo, V.

    2004-01-01

    lavage (BAL) fluid, which was not accompanied by epithelial cell injury. The treatment, however, did not change significantly the levels of anandamide and the related compound palmitoylethanolamide in the cell-free fraction of the BAL fluid. The activities of the anandamide synthetic enzymes N...... inhibitor of lung fatty acid amide hydrolase than expected from the literature, and a dose of 30 mg/kg i.p. of this compound, which produced a complete inhibition of brain anandamide metabolism, only partially inhibited the lung metabolic activity. © 2004 Elsevier Inc. All rights reserved....

  14. The fatty acid amide hydrolase inhibitor URB597 exerts anti-inflammatory effects in hippocampus of aged rats and restores an age-related deficit in long-term potentiation

    Murphy Niamh

    2012-04-01

    Full Text Available Abstract Background Several factors contribute to the deterioration in synaptic plasticity which accompanies age and one of these is neuroinflammation. This is characterized by increased microglial activation associated with increased production of proinflammatory cytokines like interleukin-1β (IL-1β. In aged rats these neuroinflammatory changes are associated with a decreased ability of animals to sustain long-term potentiation (LTP in the dentate gyrus. Importantly, treatment of aged rats with agents which possess anti-inflammatory properties to decrease microglial activation, improves LTP. It is known that endocannabinoids, such as anandamide (AEA, have anti-inflammatory properties and therefore have the potential to decrease the age-related microglial activation. However, endocannabinoids are extremely labile and are hydrolyzed quickly after production. Here we investigated the possibility that inhibiting the degradation of endocannabinoids with the fatty acid amide hydrolase (FAAH inhibitor, URB597, could ameliorate age-related increases in microglial activation and the associated decrease in LTP. Methods Young and aged rats received subcutaneous injections of the FAAH inhibitor URB597 every second day and controls which received subcutaneous injections of 30% DMSO-saline every second day for 28 days. Long-term potentiation was recorded on day 28 and the animals were sacrificed. Brain tissue was analyzed for markers of microglial activation by PCR and for levels of endocannabinoids by liquid chromatography coupled to tandem mass spectrometry. Results The data indicate that expression of markers of microglial activation, MHCII, and CD68 mRNA, were increased in the hippocampus of aged, compared with young, rats and that these changes were associated with increased expression of the proinflammatory cytokines interleukin (IL-1β and tumor necrosis factor-α (TNFα which were attenuated by treatment with URB597. Coupled with these changes, we

  15. Metal extraction by amides of carboxylic acids

    Extraction ability of various amides was studied. Data on extraction of rare earths, vanadium, molybdenum, rhenium, uranium, niobium, tantalum by N,N-dibutyl-amides of acetic, nonanic acids and fatly synthetic acids of C7-C9 fractions are presented. Effect of salting-out agents, inorganic acid concentrations on extraction process was studied. Potential ability of using amides of carboxylic acids for extractional concentration of rare earths as well as for recovery and separation of iron, rhenium, vanadium, molybdenum, uranium, niobium, and tantalum was shown

  16. Metabolism of amino acid amides in Pseudomonas putida ATCC 12633

    Hermes, H.F.M.; Croes, L.M.; Peeters, W.P.H.; Peters, P.J.H.; Dijkhuizen, L.

    1993-01-01

    The metabolism of the natural amino acid L-valine, the unnatural amino acids D-valine, and D-, L-phenylglycine (D-, L-PG), and the unnatural amino acid amides D-, L-phenylglycine amide (D, L-PG-NH2) and L-valine amide (L-Val-NH2) was studied in Pseudomonas putida ATCC 12633. The organism possessed c

  17. Borate esters as convenient reagents for direct amidation of carboxylic acids and transamidation of primary amides

    Starkov, P.; Sheppard, T. D.

    2011-01-01

    Simple borates serve as effective promoters for amide bond formation with a variety of carboxylic acids and amines. With trimethyl or tris(2,2,2-trifluoroethyl) borate, amides are obtained in good to excellent yield and high purity after a simple work-up procedure. Tris(2,2,2-trifluoroethyl) borate can also be used for the straightforward conversion of primary amides to secondary amides via transamidation.

  18. Uranium extraction with phosphoric acid amides

    Extraction of uranium by phosphorus acid monobuthylamide (MBA), dibuthylamid (DBA) and hexabuthyltriamide (HBTA) has meen investigated. The concentration constants of the process are reported. The extraction behaviour of the amides was found to be analogous to that of neutral organophosphorus extragents and to depend on the donor properties of the phosphoryl oxygen, i.e. on the number and nature of substituents by the phosphorus atom. The extraction capacity of the amides is higher than that of the phosphorus acid esters. In nitric acid solutions the highest resistance to hydrolysis was shown by HBTA. The extraction capacity of HBTA is almost insensitive to the nature of the diluting agent, be it a fatty or an aromatic hydrocarbon. With hexane used for dilution, a crystalline complex UO2(NO3)2x2HBTA was isolated

  19. Urea and amide-based inhibitors of the juvenile hormone epoxide hydrolase of the tobacco hornworm (Manduca sexta: Sphingidae).

    Severson, Tonya F; Goodrow, Marvin H; Morisseau, Christophe; Dowdy, Deanna L; Hammock, Bruce D

    2002-12-01

    A new class of inhibitors of juvenile hormone epoxide hydrolase (JHEH) of Manduca sexta and further in vitro characterization of the enzyme are reported. The compounds are based on urea and amide pharmacophores that were previously demonstrated as effective inhibitors of mammalian soluble and microsomal epoxide hydrolases. The best inhibitors against JHEH activity so far within this class are N-[(Z)-9-octadecenyl]-N'-propylurea and N-hexadecyl-N'-propylurea, which inhibited hydrolysis of a surrogate substrate (t-DPPO) with an IC(50) around 90 nM. The importance of substitution number and type was investigated and results indicated that N, N'-disubstitution with asymmetric alkyl groups was favored. Potencies of pharmacophores decreased as follows: amide>urea>carbamate>carbodiimide>thiourea and thiocarbamate for N, N'-disubstituted compounds with symmetric substituents, and urea>amide>carbamate for compounds with asymmetric N, N'-substituents. JHEH hydrolyzes t-DPPO with a K(m) of 65.6 microM and a V(max) of 59 nmol min(-1) mg(-1) and has a substantially lower K(m) of 3.6 microM and higher V(max) of 322 nmol min(-1) mg(-1) for JH III. Although none of these compounds were potent inhibitors of hydrolysis of JH III by JHEH, they are the first leads toward inhibitors of JHEH that are not potentially subject to metabolism through epoxide degradation. PMID:12429126

  20. Relation of C358A polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH with obesity and insulin resistance Relación del polimorfismo C358A del enzima del sistema endocanabinoide (hidrolasa amida acida con la obesidad y la resistencia a la insulina

    D. A. de Luis

    2010-12-01

    Full Text Available Background and aims: Recently, it has been demonstrated that the polymorphism 385 C->A of FAAH (fatty acid amide hydrolase was associated with overweight and obesity. The aim of our study was to investigate the relationship of missense polymorphism (cDNA 385 C-A of FAAH gene on obesity anthropometric parameters, cardiovascular risk factors and adipocytokines. Methods: A population of 279 females with obesity (body mass index 30 was analyzed. An indirect calorimetry, tetrapolar electrical bioimpedance, blood pressure, a serial assessment of nutritional intake with 3 days written food records and biochemical analysis (lipid profile, adipocytokines, insulin, CRP and lipoprotein-a were performed. The statistical analysis was performed for the combined C385A and A385A as a group and wild type C385C as second group. Results: One hundred and ninety four patients (69.5% had the genotype C385C (wild type group and 76 (27.2% patients had the genotype C358A or A358A (9 patients, 3.2% (mutant type group. No differences were detected between groups in anthropometric parameters and dietary intakes. Triglycerides (118.9 ± 59.9 mg/dl vs 107.4 + 51.3 mg/dl;p Antecedentes y objetivos: Recientemente, se ha demostrado que el polimorfismo 385 C/A, de FAAH (hidrolasa amida de ácidos grasos se asocia con el sobrepeso y la obesidad. El objetivo de nuestro estudio fue investigar la relación de este polimorfismo del gen de FAAH con parámetros antropométricos, factores de riesgo cardiovascular y adipocitoquinas. Métodos: Una población de 279 mujeres con obesidad (índice de masa corporal> 30 fue analizada. Se realizaron las siguientes determinaciones; calorimetría indirecta, bioimpedancia eléctrica, presión arterial, una evaluación de la ingesta nutricional de 3 días, así como un análisis bioquímico (perfil lipídico, adipocitoquinas, insulina, proteina C reactiva y lipoproteína-(a. El análisis estadístico se realizó combinando C385A y A385A como grupo

  1. Synthesis of new fatty acids amides from aminolysis of fatty acid methyl esters (FAMEs)

    Recent biochemical and pharmacological studies have led to the characterization of different fatty acid amides as a new family of biologically active lipids. Here, we describe the synthesis of new amides from C16:0, 18:0, 18:1 and 18:1, OH fatty acids (FFA) families with cyclic and acyclic amines and demonstrate for the first time that these compounds produce cytotoxic effects. Application of this method to the synthesis of fatty acid amides was performed using the esters aminolysis as a key step and various carboxylic amides were prepared in good yield from fatty acid methyl esters (FAMEs). (author)

  2. New Umami Amides: Structure-Taste Relationship Studies of Cinnamic Acid Derived Amides and the Natural Occurrence of an Intense Umami Amide in Zanthoxylum piperitum.

    Frerot, Eric; Neirynck, Nathalie; Cayeux, Isabelle; Yuan, Yoyo Hui-Juan; Yuan, Yong-Ming

    2015-08-19

    A series of aromatic amides were synthesized from various acids and amines selected from naturally occurring structural frameworks. These synthetic amides were evaluated for umami taste in comparison with monosodium glutamate. The effect of the substitution pattern of both the acid and the amine parts on umami taste was investigated. The only intensely umami-tasting amides were those made from 3,4-dimethoxycinnamic acid. The amine part was more tolerant to structural changes. Amides bearing an alkyl- or alkoxy-substituted phenylethylamine residue displayed a clean umami taste as 20 ppm solutions in water. Ultraperformance liquid chromatography coupled with a high quadrupole-Orbitrap mass spectrometer (UPLC/MS) was subsequently used to show the natural occurrence of these amides. (E)-3-(3,4-Dimethoxyphenyl)-N-(4-methoxyphenethyl)acrylamide was shown to occur in the roots and stems of Zanthoxylum piperitum, a plant of the family Rutaceae growing in Korea, Japan, and China. PMID:26230212

  3. Intramolecular Amide Hydrolysis in N-Methylmaleamic Acid Revisited

    2002-01-01

    The intramolecular amide hydrolysis of N-methylmaleamic acid have been revisited by use of density functional theory and inclusion of solvent effects. The results indicate that concerted reaction mechanism is favored over stepwise reaction mechanism. This is in agreement with the previous theoretical study. Sovlent effects have significant influence on the reaction barrier.

  4. Inhibition of acid hydrolase activity in human granulocytes by PUVA treatment

    The activity of acid hydrolases in peripheral blood granulocytes was determined. No significant differences could be revealed between healthy and psoriatic donors. During PUVA therapy of psoriasis patients the activity of acid hydrolases in granulocytes was moderately decreased in most cases, but the differences were not significant (high individual variability). Isolated granulocytes were treated in vitro with doses of 8-methoxypsoralen and UVA light as can be achieved in situ in the epidermis during PUVA therapy. A reduced acid hydrolases activity was found in the cells after the treatment, which was not due to secretion of the enzyme or cytotoxic damage. The presence of reduced glutathione prevented this effect. Free extracellular acid hydrolases were not inactivated by PUVA. PUVA-treated granulocytes showed an unimpaired superoxide generation after phagocytic stimulation. These results show that an intracellular inactivation of acid hydrolases and possibly other lysosomal enzymes in granulocytes infiltrating the psoriatic epidermis contribute to the antipsoriatic effects of PUVA therapy. (author)

  5. Toxocara canis: Larvicidal activity of fatty acid amides.

    Mata-Santos, Taís; D'Oca, Caroline da Ros Montes; Mata-Santos, Hílton Antônio; Fenalti, Juliana; Pinto, Nitza; Coelho, Tatiane; Berne, Maria Elisabeth; da Silva, Pedro Eduardo Almeida; D'Oca, Marcelo Gonçalves Montes; Scaini, Carlos James

    2016-02-01

    Considering the therapeutic potential of fatty acid amides, the present study aimed to evaluate their in vitro activity against Toxocara canis larvae and their cytotoxicity for the first time. Linoleylpyrrolidilamide was the most potent, with a minimal larvicidal concentration (MLC) of 0.05 mg/mL and 27% cytotoxicity against murine peritoneal macrophages C57BL/6 mice, as assessed by the MTT assay. PMID:26783180

  6. Recent developments in amide synthesis: direct amidation of carboxylic acids and transamidation reactions

    Lanigan, R. M.; Sheppard, T. D.

    2013-01-01

    The synthesis of amides is of huge importance in a wide variety of industrial and academic fields and is of particular significance in the synthesis of pharmaceuticals. Many of the well established methods for amide synthesis involve reagents that are difficult to handle and lead to the generation of large quantities of waste products. As a consequence, there has been a considerable amount of interest in the development of new approaches to amide synthesis. Over the past few years a wide rang...

  7. Iodine-Catalyzed Decarboxylative Amidation of β,γ-Unsaturated Carboxylic Acids with Chloramine Salts Leading to Allylic Amides.

    Kiyokawa, Kensuke; Kojima, Takumi; Hishikawa, Yusuke; Minakata, Satoshi

    2015-10-26

    The iodine-catalyzed decarboxylative amidation of β,γ-unsaturated carboxylic acids with chloramine salts is described. This method enables the regioselective synthesis of allylic amides from various types of β,γ-unsaturated carboxylic acids containing substituents at the α- and β-positions. In the reaction, N-iodo-N-chloroamides, generated by the reaction of a chloramine salt with I2 , function as a key active species. The reaction provides an attractive alternative to existing methods for the synthesis of useful secondary allylic amine derivatives. PMID:26493878

  8. Lipase-catalyzed synthesis of fatty acid amide (erucamide) using fatty acid and urea.

    Awasthi, Neeraj Praphulla; Singh, R P

    2007-01-01

    Ammonolysis of fatty acids to the corresponding fatty acid amides is efficiently catalysed by Candida antartica lipase (Novozym 435). In the present paper lipase-catalysed synthesis of erucamide by ammonolysis of erucic acid and urea in organic solvent medium was studied and optimal conditions for fatty amides synthesis were established. In this process erucic acid gave 88.74 % pure erucamide after 48 hour and 250 rpm at 60 degrees C with 1:4 molar ratio of erucic acid and urea, the organic solvent media is 50 ml tert-butyl alcohol (2-methyl-2-propanol). This process for synthesis is economical as we used urea in place of ammonia or other amidation reactant at atmospheric pressure. The amount of catalyst used is 3 %. PMID:17898456

  9. Direct amidation of amino acid derivatives catalyzed by arylboronic acids : applications in dipeptide synthesis.

    Liu, S.; Yang, Y.; Liu, X.; Ferdousi, F. K.; Batsanov, A.S.; Whiting, A

    2013-01-01

    The direct amidation of amino acid derivatives catalyzed by arylboronic acids has been examined. The reaction was generally slow relative to simple amine-carboxylic acid combinations though proceeded at 65–68 °C generally avoiding racemization. 3,4,5-Trifluorophenylboronic and o-nitrophenylboronic acids were found to be the best catalysts, though for slower dipeptide formations, high catalyst loadings were required and an interesting synergistic catalytic effect between two arylboronic acids ...

  10. ISOLATION AND CHARACTERIZATION OF AN ACID, BILE SALT-INDEPENDENT, RETINYL ESTER HYDROLASE FROM RAT LIVER MICROSOMES

    Previous work in this laboratory has revealed the presence of both acidic and neutral bile-salt independent retinyl ester hydrolase activities in rat liver homogenates. Here we present the purification, identification and characterization of an acid retinyl ester hydrolase activity from solubilized ...

  11. Kynurenic acid amides as novel NR2B selective NMDA receptor antagonists.

    Borza, István; Kolok, Sándor; Galgóczy, Kornél; Gere, Anikó; Horváth, Csilla; Farkas, Sándor; Greiner, István; Domány, György

    2007-01-15

    A novel series of kynurenic acid amides, ring-enlarged derivatives of indole-2-carboxamides, was prepared and identified as in vivo active NR2B subtype selective NMDA receptor antagonists. The synthesis and SAR studies are discussed. PMID:17074483

  12. Peptidoglycan Hydrolases of Local Lactic Acid Bacteria from Kazakh Traditional Food

    Serik Shaikhin

    2014-01-01

    Full Text Available Introduction: Peptidoglycan (PG is a major component of the cell wall of Gram-positive bacteria and is essential for maintaining the integrity of the bacterial cell and its shape. The bacteria synthesize PG hydrolases, which are capable of cleaving the covalent bonds of PG. They also play an important role in modeling PG, which is required for bacterial growth and division. In an era of increasing antibiotic-resistant pathogens, PG hydrolases that destroy these important structures of the cell wall act as a potential source of new antimicrobials. The aim of this study is to identify the main PG hydrolases of local lactic acid bacteria isolated from traditional foods that enhance probiotic activity of a biological preparation. Methods. Lactococcus lactis 17А and Lactococcus garvieae 19А were isolated from the traditional sausage-like meat product called kazy. They were isolated according to standards methods of microbiology. Genetic identification of the isolates were tested by determining the nucleotide sequences of 16S rDNA. The Republican collection of microorganisms took strains of Lactobacillus casei subsp. Rhamnosus 13-P, L. delbrueckii subsp. lactis CG-1 B-RKM 0044 from cheese, Lactobacillus casei subsp. casei B-RKM 0202 from homemade butter. They used the standard technique of renaturating polyacrylamide gel electrophoresis to detect PG hydrolases activity. Results. According to the profiles of PG hydrolase activity on zymograms, the enzymes of Lactococci 17A and 19A in kazy are similar in electrophoretic mobility to major autolysin AcmA, while the lactobacilli of industrial and home-made dairy products have enzymes similar to extracellular proteins p40 and p75, which have probiotic activity. Conclusions. Use of peptidoglycan hydrolases seems to be an interesting approach in the fight against multi-drug resistant strains of bacteria and could be a valuable tool for the treatment of diseases caused by these microorganisms in Kazakhstan.

  13. Syntheses of Macrocyclic Amides from L-Amino Acid Esters by RCM

    2007-01-01

    A series of succinate-derived macrocyclic amides( 1 ) was synthesized via ring-closing metathesis (RCM) as the key step. The substrate included 12 to 15 members. The metathesis precursors were obtained from the amide coupling of tert-butyl 3-carboxyhex-5-enoate(2) with numerous side-chain alkenylated amino acid esters of general type(3)derived from L-lysine and L-ornithine.

  14. Substituted Amides of Pyrazine-2-carboxylic acids: Synthesis and Biological Activity

    Katarina Kralova; Jiri Kunes; Miroslav Miletin; Martin Dolezal

    2002-01-01

    Condensation of 6-chloro-, 5-tert-butyl- or 6-chloro-5-tert-butylpyrazine-2-carboxylic acid chloride with ring substituted anilines yielded a series of amides, which were tested for their in vitro antimycobacterial, antifungal and photosynthesis-inhibiting activities. The highest antituberculotic activity (72% inhibition) against Mycobacterium tuberculosis and the highest lipophilicity (log P = 6.85) were shown by the 3,5-bistrifluoromethylphenyl amide of 5-tert-butyl-6-chloropyrazine-2-carbo...

  15. Cell- and ligand-specific dephosphorylation of acid hydrolases: Evidence that the mannose 6-phosphatase is controlled by compartmentalization

    Einstein, R.; Gabel, C.A. (Columbia Univ. College of Physicians and Surgeons, NY (USA))

    1991-01-01

    Mouse L cells that possess the cation-independent mannose 6-phosphate (Man 6-P)/insulin-like growth factor (IGF) II receptor change the extent to which they dephosphorylate endocytosed acid hydrolases in response to serum. To investigate the mechanism by which dephosphorylation competence is regulated, the dephosphorylation of individual acid hydrolases was studied in Man 6-P/IGF II receptor-positive and -deficient cell lines. 125I-labeled Man 6-P-containing acid hydrolases were proteolytically processed but remained phosphorylated when endocytosed by receptor-positive L cells maintained in the absence of serum; after the addition of serum, however, the cell-associated hydrolases were dephosphorylated. Individual hydrolases were dephosphorylated at distinct rates and to different extents. In contrast, the same hydrolases were dephosphorylated equally and completely after entry into Man 6-P/IGF II receptor-positive Chinese hamster ovary (CHO) cells. The dephosphorylation competence of Man 6-P/IGF II receptor-deficient mouse J774 cells was more limited. beta-Glucuronidase produced by these cells underwent a limited dephosphorylation in transit to lysosomes such that diphosphorylated oligosaccharides were converted to monophosphorylated species. The overall quantity of phosphorylated oligosaccharides associated with the enzyme, however, did not decrease within the lysosomal compartment. Likewise, beta-glucuronidase was not dephosphorylated when introduced into J774 cells via Fc receptor-mediated endocytosis. The CHO and J774 cell lysosomes, therefore, display opposite extremes with respect to their capacity to dephosphorylate acid hydrolases; within CHO cell lysosomes acid hydrolases are rapidly and efficiently dephosphorylated, but within J774 cell lysosomes the same acid hydrolases remain phosphorylated.

  16. Cell- and ligand-specific dephosphorylation of acid hydrolases: Evidence that the mannose 6-phosphatase is controlled by compartmentalization

    Mouse L cells that possess the cation-independent mannose 6-phosphate (Man 6-P)/insulin-like growth factor (IGF) II receptor change the extent to which they dephosphorylate endocytosed acid hydrolases in response to serum. To investigate the mechanism by which dephosphorylation competence is regulated, the dephosphorylation of individual acid hydrolases was studied in Man 6-P/IGF II receptor-positive and -deficient cell lines. 125I-labeled Man 6-P-containing acid hydrolases were proteolytically processed but remained phosphorylated when endocytosed by receptor-positive L cells maintained in the absence of serum; after the addition of serum, however, the cell-associated hydrolases were dephosphorylated. Individual hydrolases were dephosphorylated at distinct rates and to different extents. In contrast, the same hydrolases were dephosphorylated equally and completely after entry into Man 6-P/IGF II receptor-positive Chinese hamster ovary (CHO) cells. The dephosphorylation competence of Man 6-P/IGF II receptor-deficient mouse J774 cells was more limited. beta-Glucuronidase produced by these cells underwent a limited dephosphorylation in transit to lysosomes such that diphosphorylated oligosaccharides were converted to monophosphorylated species. The overall quantity of phosphorylated oligosaccharides associated with the enzyme, however, did not decrease within the lysosomal compartment. Likewise, beta-glucuronidase was not dephosphorylated when introduced into J774 cells via Fc receptor-mediated endocytosis. The CHO and J774 cell lysosomes, therefore, display opposite extremes with respect to their capacity to dephosphorylate acid hydrolases; within CHO cell lysosomes acid hydrolases are rapidly and efficiently dephosphorylated, but within J774 cell lysosomes the same acid hydrolases remain phosphorylated

  17. Synthesis and effect of fatty acid amides as friction modifiers in petroleum base stock.

    Khalkar, Sharmishtha; Bhowmick, DiptiNarayan; Pratap, Amit

    2013-01-01

    Fatty acid amides were prepared by using Lewis acid as a catalyst. The products from reaction was subjected to solvent extraction with chloroform and then followed by purification with n-hexane, ethanol and acetonitrile. Fatty acid amide, characterized by various physicochemical and tribological properties like wear scar, weld load and coefficient of friction. These compounds found good antiwear (AW) and extreme pressure (EP) additive. The addition of various EP and AW additives in lubricating oil is an important and effective way to reduce friction and wear. Fatty acid amides were used as antiwear and friction modifier additive and a comparative study was carried out for 1%, 3%, 5% additive blend with commercial petroleum base stocks 150N and 500N. PMID:24200937

  18. Pharmaceuticals and Surfactants from Alga-Derived Feedstock: Amidation of Fatty Acids and Their Derivatives with Amino Alcohols.

    Tkacheva, Anastasia; Dosmagambetova, Inkar; Chapellier, Yann; Mäki-Arvela, Päivi; Hachemi, Imane; Savela, Risto; Leino, Reko; Viegas, Carolina; Kumar, Narendra; Eränen, Kari; Hemming, Jarl; Smeds, Annika; Murzin, Dmitry Yu

    2015-08-24

    Amidation of renewable feedstocks, such as fatty acids, esters, and Chlorella alga based biodiesel, was demonstrated with zeolites and mesoporous materials as catalysts and ethanolamine, alaninol, and leucinol. The last two can be derived from amino acids present in alga. The main products were fatty alkanol amides and the corresponding ester amines, as confirmed by NMR and IR spectroscopy. Thermal amidation of technical-grade oleic acid and stearic acid at 180 °C with ethanolamine were non-negligible; both gave 61% conversion. In the amidation of stearic acid with ethanolamine, the conversion over H-Beta-150 was 80% after 3 h, whereas only 63% conversion was achieved for oleic acid; this shows that a microporous catalyst is not suitable for this acid and exhibits a wrinkled conformation. The highest selectivity to stearoyl ethanolamide of 92% was achieved with mildly acidic H-MCM-41 at 70% conversion in 3 h at 180 °C. Highly acidic catalysts favored the formation of the ester amine, whereas the amide was obtained with a catalyst that exhibited an optimum acidity. The conversion levels achieved with different fatty acids in the range C12-C18 were similar; this shows that the fatty acid length does not affect the amidation rate. The amidation of methyl palmitate and biodiesel gave low conversions over an acidic catalyst, which suggested that the reaction mechanism in the amidation of esters was different. PMID:26197759

  19. Inhibition of epoxide hydrolase by valproic acid in epileptic patients receiving carbamazepine.

    Robbins, D K; Wedlund, P J; Kuhn, R.; Baumann, R J; Levy, R.H.; Chang, S.L.

    1990-01-01

    The effect of valproic acid (VPA) on the disposition of carbamazepine-10,11-epoxide (epoxide) was studied in five epileptic patients on chronic carbamazepine (CBZ) therapy. The individual pharmacokinetic parameters influencing epoxide disposition were determined in the presence and absence of VPA. VPA significantly decreased the clearance of unbound epoxide (an in vivo index of epoxide hydrolase activity), but did not appear to affect epoxide formation. VPA also increased the free concentrati...

  20. One pot direct synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent

    Kangani, Cyrous O.; Kelley, David E.

    2005-01-01

    A mild and highly efficient one pot–one step condensation and/or condensation–cyclization of various acids to amides and/or oxazolines using Deoxo-Fluor reagents is described. Parallel syntheses of various free fatty acids with 2-amino-2, 2-dimethyl-1-propanol resulted with excellent yields.

  1. New families in the classification of glycosyl hydrolases based on amino acid sequence similarities.

    Henrissat, B; Bairoch, A

    1993-01-01

    301 glycosyl hydrolases and related enzymes corresponding to 39 EC entries of the I.U.B. classification system have been classified into 35 families on the basis of amino-acid-sequence similarities [Henrissat (1991) Biochem. J. 280, 309-316]. Approximately half of the families were found to be monospecific (containing only one EC number), whereas the other half were found to be polyspecific (containing at least two EC numbers). A > 60% increase in sequence data for glycosyl hydrolases (181 additional enzymes or enzyme domains sequences have since become available) allowed us to update the classification not only by the addition of more members to already identified families, but also by the finding of ten new families. On the basis of a comparison of 482 sequences corresponding to 52 EC entries, 45 families, out of which 22 are polyspecific, can now be defined. This classification has been implemented in the SWISS-PROT protein sequence data bank. PMID:8352747

  2. Characterization of Two New Glycosyl Hydrolases from the Lactic Acid Bacterium Carnobacterium piscicola Strain BA

    Coombs, Jonna; Brenchley, Jean E.

    2001-01-01

    Three genes with homology to glycosyl hydrolases were detected on a DNA fragment cloned from a psychrophilic lactic acid bacterium isolate, Carnobacterium piscicola strain BA. A 2.2-kb region corresponding to an α-galactosidase gene, agaA, was followed by two genes in the same orientation, bgaB, encoding a 2-kb β-galactosidase, and bgaC, encoding a structurally distinct 1.76-kb β-galactosidase. This gene arrangement had not been observed in other lactic acid bacteria, including Lactococcus la...

  3. Gas-Phase Amidation of Carboxylic Acids with Woodward's Reagent K Ions

    Peng, Zhou; Pilo, Alice L.; Luongo, Carl A.; McLuckey, Scott A.

    2015-06-01

    Gas-phase amidation of carboxylic acids in multiply-charged peptides is demonstrated via ion/ion reactions with Woodward's reagent K (wrk) in both positive and negative mode. Woodward's reagent K, N-ethyl-3-phenylisoxazolium-3'-sulfonate, is a commonly used reagent that activates carboxylates to form amide bonds with amines in solution. Here, we demonstrate that the analogous gas-phase chemistry occurs upon reaction of the wrk ions and doubly protonated (or doubly deprotonated) peptide ions containing the carboxylic acid functionality. The reaction involves the formation of the enol ester intermediate in the electrostatic complex. Upon collisional activation, the ethyl amine on the reagent is transferred to the activated carbonyl carbon on the peptide, resulting in the formation of an ethyl amide (addition of 27 Da to the peptide) with loss of a neutral ketene derivative. Further collision-induced dissociation (CID) of the products and comparison with solution-phase amidation product confirms the structure of the ethyl amide.

  4. Molecular Basis of Prodrug Activation by Human Valacyclovirase, an [alpha]-Amino Acid Ester Hydrolase

    Lai, Longsheng; Xu, Zhaohui; Zhou, Jiahai; Lee, Kyung-Dall; Amidon, Gordon L. (Michigan)

    2008-07-08

    Chemical modification to improve biopharmaceutical properties, especially oral absorption and bioavailability, is a common strategy employed by pharmaceutical chemists. The approach often employs a simple structural modification and utilizes ubiquitous endogenous esterases as activation enzymes, although such enzymes are often unidentified. This report describes the crystal structure and specificity of a novel activating enzyme for valacyclovir and valganciclovir. Our structural insights show that human valacyclovirase has a unique binding mode and specificity for amino acid esters. Biochemical data demonstrate that the enzyme hydrolyzes esters of {alpha}-amino acids exclusively and displays a broad specificity spectrum for the aminoacyl moiety similar to tricorn-interacting aminopeptidase F1. Crystal structures of the enzyme, two mechanistic mutants, and a complex with a product analogue, when combined with biochemical analysis, reveal the key determinants for substrate recognition; that is, a flexible and mostly hydrophobic acyl pocket, a localized negative electrostatic potential, a large open leaving group-accommodating groove, and a pivotal acidic residue, Asp-123, after the nucleophile Ser-122. This is the first time that a residue immediately after the nucleophile has been found to have its side chain directed into the substrate binding pocket and play an essential role in substrate discrimination in serine hydrolases. These results as well as a phylogenetic analysis establish that the enzyme functions as a specific {alpha}-amino acid ester hydrolase. Valacyclovirase is a valuable target for amino acid ester prodrug-based oral drug delivery enhancement strategies.

  5. Human microsomal epoxide hydrolase: genetic polymorphism and functional expression in vitro of amino acid variants

    Hassett, Christopher; Aicher, Lauri; Sidhu, Jaspreet S.

    2016-01-01

    Human microsomal epoxide hydrolase (mEH) is a biotransformation enzyme that metabolizes reactive epoxide intermediates to more water-soluble trans-dihydrodiol derivatives. We compared protein-coding sequences from six full-length human mEH DNA clones and assessed potential amino acid variation at seven positions. The prevalence of these variants was assessed in at least 37 unrelated individuals using polymerase chain reaction experiments. Only Tyr/His 113 (exon 3) and His/Arg 139 (exon 4) variants were observed. The genotype frequencies determined for residue 113 alleles indicate that this locus may not be in Hardy – Weinberg equilibrium, whereas frequencies observed for residue 139 alleles were similar to expected values. Nucleotide sequences coding for the variant amino acids were constructed in an mEH cDNA using site-directed mutagenesis, and each was expressed in vitro by transient transfection of COS-1 cells. Epoxide hydrolase mRNA level, catalytic activity, and immunoreactive protein were evaluated for each construct. The results of these analyses demonstrated relatively uniform levels of mEH RNA expression between the constructs. mEH enzymatic activity and immunoreactive protein were strongly correlated, indicating that mEH specific activity was similar for each variant. However, marked differences were noted in the relative amounts of immunoreactive protein and enzymatic activity resulting from the amino acid substitutions. These data suggest that common human mEH amino acid polymorphisms may alter enzymatic function, possibly by modifying protein stability. PMID:7516776

  6. CUTICULAR LIPIDS OF THE STORED FOOD PEST, LIPOSCELIS BOSTRYCHOPHILA BADONNEL (PSOCOPTERA: LIPOSCELIDIDAE): HYDROCARBONS, ALDEHYDES, FATTY ACIDS AND FATTY ACID AMIDES

    The booklouse, Liposcelis bostrychophila, has increasingly become a common pest of stored food products worldwide. We report here the cuticular hydrocarbon composition of this pest (the first report of the hydrocarbons of any member of the Order Psocoptera) and the first report of fatty acid amides...

  7. Substituted Amides of Pyrazine-2-carboxylic acids: Synthesis and Biological Activity

    Katarina Kralova

    2002-03-01

    Full Text Available Condensation of 6-chloro-, 5-tert-butyl- or 6-chloro-5-tert-butylpyrazine-2-carboxylic acid chloride with ring substituted anilines yielded a series of amides, which were tested for their in vitro antimycobacterial, antifungal and photosynthesis-inhibiting activities. The highest antituberculotic activity (72% inhibition against Mycobacterium tuberculosis and the highest lipophilicity (log P = 6.85 were shown by the 3,5-bistrifluoromethylphenyl amide of 5-tert-butyl-6-chloropyrazine-2-carboxylic acid (2o. The 3-methylphenyl amides of 6-chloro- and 5-tert-butyl-6-chloro-pyrazine-2-carboxylic acid (2d and 2f exhibited only a poor in vitro antifungal effect (MIC = 31.25-500 μmol·dm-3 against all strains tested, although the latter was the most active antialgal compound (IC50 = 0.063 mmol·dm-3. The most active inhibitor of oxygen evolution rate in spinach chloroplasts was the (3,5-bis-trifluoromethylphenylamide of 6-chloropyrazine-2-carboxylic acid (2m, IC50 = 0.026 mmol·dm-3.

  8. Synthesis and Properties of Lactic Acid-based Cross-linked Poly(ester-amide)

    Yue Ying HE; Cong Ming XIAO

    2006-01-01

    A novel lactic acid-based cross-linked poly(ester-amide) (LCPEA) was synthesized. The gel fraction of the LCPEA could be modulated by the reaction conditions and it affected the mechanical and thermal properties of the LCPEA. The tensile strength, elastic modulus and bend strength of the LCPEA of 65% gel fraction were 4.65, 136.55 and 39.63 MPa, respectively. The thermal decomposition temperature (50 wt%) of the LCPEA was around 410 ℃.

  9. Chiral amide from (1, 2)-(+)-norephedrine and furoic acid: An efficient catalyst for asymmetric Reformatsky reaction

    Nallamuthu Ananthi; Sivan Velmathi

    2014-01-01

    Chiral amide derived from (1, 2)-(+)-norephedrine and 2-furoic acid was found to catalyse the asymmetric Reformatsky reaction between prochiral aldehydes and α-bromo ethylacetate with diethylzinc as zinc source. The corresponding chiral -hydroxy esters were formed in 99% yield with over 80% enantiomeric excess. The presence of air was found to be essential for the effective C-C bond formation. The mechanism for the catalytic reaction was proposed.

  10. Purification and characterization of a cis-epoxysuccinic acid hydrolase from Nocardia tartaricans CAS-52, and expression in Escherichia coli.

    Wang, Ziqiang; Wang, Yunshan; Su, Zhiguo

    2013-03-01

    A highly enantioselective cis-epoxysuccinic acid hydrolase from Nocardia tartaricans was purified to electrophoretic homogeneity. The enzyme was purified 184-fold with a yield of 18.8 %. The purified cis-epoxysuccinic acid hydrolase had a monomeric molecular weight of 28 kDa, and its optimum conditions were 37 °C and pH 7-9. With sodium cis-epoxysuccinate as the substrate, Michaelis-Menten enzyme kinetics analysis gave a Km value of 35.71 mM and a Vmax of 2.65 mM min(-1). The enzyme was activated by Ni(2+) and Al(3+), while strongly inhibited by Fe(3+), Fe(2+), Cu(2+), and Ag(+). The cis-epoxysuccinic acid hydrolase gene was cloned, and its open reading frame sequence predicted a protein composed of 253 amino acids. A pET11a expression plasmid carrying the gene under the control of the T7 promoter was introduced into Escherichia coli, and the cis-epoxysuccinic acid hydrolase gene was successfully expressed in the recombinant strains. PMID:22552902

  11. MATE Transporter-Dependent Export of Hydroxycinnamic Acid Amides[OPEN

    Eschen-Lippold, Lennart; Gorzolka, Karin; Matern, Andreas; Marillonnet, Sylvestre; Böttcher, Christoph; Rosahl, Sabine

    2016-01-01

    The ability of Arabidopsis thaliana to successfully prevent colonization by Phytophthora infestans, the causal agent of late blight disease of potato (Solanum tuberosum), depends on multilayered defense responses. To address the role of surface-localized secondary metabolites for entry control, droplets of a P. infestans zoospore suspension, incubated on Arabidopsis leaves, were subjected to untargeted metabolite profiling. The hydroxycinnamic acid amide coumaroylagmatine was among the metabolites secreted into the inoculum. In vitro assays revealed an inhibitory activity of coumaroylagmatine on P. infestans spore germination. Mutant analyses suggested a requirement of the p-coumaroyl-CoA:agmatine N4-p-coumaroyl transferase ACT for the biosynthesis and of the MATE transporter DTX18 for the extracellular accumulation of coumaroylagmatine. The host plant potato is not able to efficiently secrete coumaroylagmatine. This inability is overcome in transgenic potato plants expressing the two Arabidopsis genes ACT and DTX18. These plants secrete agmatine and putrescine conjugates to high levels, indicating that DTX18 is a hydroxycinnamic acid amide transporter with a distinct specificity. The export of hydroxycinnamic acid amides correlates with a decreased ability of P. infestans spores to germinate, suggesting a contribution of secreted antimicrobial compounds to pathogen defense at the leaf surface. PMID:26744218

  12. Partial purification and characterization of an inducible indole-3-acetyl-L-aspartic acid hydrolase from Enterobacter agglomerans

    Chou, Jyh-Ching [Department of Agriculture, Beltsville, MD (United States)]|[Univ. of Maryland, College Park, MD (United States); Cohen, J.D.; Mulbry, W.W. [Department of Agriculture, Beltsville, MD (United States)] [and others

    1996-11-01

    Indole-3-acetyl-amino acid conjugate hydrolases are believed to be important in the regulation of indole-3-acetic acid (IAA) metabolism in plants and therefore have potential uses for the alteration of plant IAA metabolism. To isolate bacterial strains exhibiting significant indole-3-acetyl-aspartate (IAA-Asp) hydrolase activity, a sewage sludge inoculation was cultured under conditions in which IAA-Asp served as the sole source of carbon and nitrogen. One isolate, Enterobacter agglomerans, showed hydrolase activity inducible by IAA-L-Asp or N-acetyl-L-Asp but not by IAA, (NH{sub 4}){sub 2}SO{sub 4}, urea, or indoleacetamide. Among a total of 17 IAA conjugates tested as potential substrates, the enzyme had an exclusively high substrate specificity for IAA-L-Asp of 13.5 mM. The optimal pH for this enzyme was between 8.0 and 8.5. In extraction buffer containing 0.8 mM Mg{sup 2+} the hydrolase activity was inhibited to 80% by 1 mM dithiothreitol and to 60% by 1 mm CuSO{sub 4}; the activity was increased by 40% with 1mM MnSO{sub 4}. However, in extraction buffer with no trace elements, the hydrolase activity was inhibited to 50% by either 1 mM dithiothreitol or 1% Triton X-100 (Sigma). These results suggest that disulfide bonding might be essential for enzyme activity. Purification of the hydrolase by hydroxyapatite and TSK-phenyl (HP-Genenchem, South San Francisco, CA) preparative high-performance liquid chromatography yielded a major 45-kD polypeptide as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 45 refs., 5 figs., 3 tabs.

  13. Regiospecific tritium labeling of aromatic acids, amides, amines and heterocyclics using homogeneous rhodium trichloride and ruthenium acetylacetonate catalysts

    Homogeneous rhodium trichloride has been found to promote ortho-tritiation with high regioselectivity in a wide range of aromatic carboxylic acids, amides and aralkylamines. Less successful results were obtained using o-chlorobenzoic and o-anisic acids where some decomposition was seen, and in acids and amides of the phenolic type, where a degree of electrophilic exchange accompanies the ortho-exchange. The same catalyst has also been used to regiospecifically label a number of heterocyclics. In the course of investigations with other metal complexes ruthenium acetylacetonate has been identified as an excellent promoter of ortho-exchange in benzoic acids. (author)

  14. Synthesis, Anti-HCV, Antioxidant and Reduction of Intracellular Reactive Oxygen Species Generation of a Chlorogenic Acid Analogue with an Amide Bond Replacing the Ester Bond

    Ling-Na Wang

    2016-06-01

    Full Text Available Chlorogenic acid is a well known natural product with important bioactivities. It contains an ester bond formed between the COOH of caffeic acid and the 3-OH of quinic acid. We synthesized a chlorogenic acid analogue, 3α-caffeoylquinic acid amide, using caffeic and quinic acids as starting materials. The caffeoylquinc acid amide was found to be much more stable than chlorogenic acid and showed anti-Hepatitis C virus (anti-HCV activity with a potency similar to chlorogenic acid. The caffeoylquinc acid amide potently protected HepG2 cells against oxidative stress induced by tert-butyl hydroperoxide.

  15. Visible-Light-Mediated Synthesis of Amides from Aldehydes and Amines via in Situ Acid Chloride Formation.

    Iqbal, Naeem; Cho, Eun Jin

    2016-03-01

    An efficient visible-light photocatalysis-based one-pot amide synthesis method was developed; visible-light irradiation of a mixture of an aldehyde, tert-butyl hydrogen peroxide, and N-chlorosuccinimide using a Ru(bpy)3Cl2 photocatalyst afforded an acid chloride, which subsequently reacted with amine to yield the corresponding amide. The reaction was used to synthesize moclobemide and a D3 receptor intermediate. PMID:26836367

  16. Fatty acid amide supplementation decreases impulsivity in young adult heavy drinkers.

    van Kooten, Maria J; Veldhuizen, Maria G; de Araujo, Ivan E; O'Malley, Stephanie S; Small, Dana M

    2016-03-01

    Compromised dopamine signaling in the striatum has been associated with the expression of impulsive behaviors in addiction, obesity and alcoholism. In rodents, intragastric infusion of the fatty acid amide oleoylethanolamide increases striatal extracellular dopamine levels via vagal afferent signaling. Here we tested whether supplementation with PhosphoLean™, a dietary supplement that contains the precursor of the fatty acid amide oleoylethanolamide (N-oleyl-phosphatidylethanolamine), would reduce impulsive responding and alcohol use in heavy drinking young adults. Twenty-two individuals were assigned to a three-week supplementation regimen with PhosphoLean™ or placebo. Impulsivity was assessed with self-report questionnaires and behavioral tasks pre- and post-supplementation. Although self-report measures of impulsivity did not change, supplementation with PhosphoLean™, but not placebo, significantly reduced false alarm rate on a Go/No-Go task. In addition, an association was found between improved sensitivity on the Go/No-Go task and reduced alcohol intake. These findings provide preliminary evidence that promoting fatty acid derived gut-brain dopamine communication may have therapeutic potential for reducing impulsivity in heavy drinkers. PMID:26656766

  17. Amide functionalized Calix-Benzocrown-6 ionophore for extraction of cesium from highly concentrated nitric acid medium

    A series of novel calix(4)arene-benzocrown-6 amide (CBCA) ligands in 1,3-alternate conformations with amidic group attached to aromatic ring of the polyether ring network have been synthesised and evaluated for extraction of caesium from nitric acid medium (1-10M). Isodecyl alcohol (IDA) and o-nitrophenyl hexyl ether (o-NPHE) modified calix/dodecane have been used for extraction studies. The extraction of Cs increases with nitric acid concentration, the maxima is obtained at ∼ 4.5M for calix-benzo-crown-6 (CBC) used as standard, whereas, in case of CBCA this maxima reaches to ∼ 8M nitric acid concentration. This difference is attributed to neutralization of nitric acid by intramolecular buffering effect of amidic group of CBCA. (author)

  18. Isolation, identification and quantification of unsaturated fatty acids, amides, phenolic compounds and glycoalkaloids from potato peel.

    Wu, Zhi-Gang; Xu, Hai-Yan; Ma, Qiong; Cao, Ye; Ma, Jian-Nan; Ma, Chao-Mei

    2012-12-15

    Eleven compounds were isolated from potato peels and identified. Their structures were determined by interpretation of UV, MS, 1D, and 2D NMR spectral data and by comparison with reported data. The main components of the potato peels were found to be chlorogenic acid and other phenolic compounds, accompanied by 2 glycoalkaloids, 3 low-molecular-weight amide compounds, and 2 unsaturated fatty acids, including an omega-3 fatty acid. The potato peels showed more potent radical scavenging activity than the flesh. The quantification of the 11 components indicated that the potato peels contained a higher amount of phenolic compounds than the flesh. These results suggest that peel waste from the industry of potato chips and fries may be a source of useful compounds for human health. PMID:22980823

  19. Electrostatic interaction of pi-acidic amides with hydrogen-bond acceptors.

    Li, Yi; Snyder, Lawrence B; Langley, David R

    2003-10-01

    Interactions between N-methylacetamide (NMA) and N-methylated derivatives of uracil, isocyanurate and barbituric acid have been studied using ab initio methods at the local MP2/6-31G** level of theory. The results were compared to similar interactions between the oxygen atom of NMA and the pi-clouds of perfluorobenzene, quinone and trimethyltriazine. The pi-acidic amides of isocyanurate and barbituric acid were found to interact with a hydrogen bond acceptor primarily through electrostatic attractions. These groups may be used as alternatives of a hydrogen bond donor to complement a hydrogen bond acceptor or an anion in molecular recognition and drug design. Examples of such interactions were identified through a search of the CSD database. PMID:12951105

  20. Cinnamic acid amides from Tribulus terrestris displaying uncompetitive α-glucosidase inhibition.

    Song, Yeong Hun; Kim, Dae Wook; Curtis-Long, Marcus J; Park, Chanin; Son, Minky; Kim, Jeong Yoon; Yuk, Heung Joo; Lee, Keun Woo; Park, Ki Hun

    2016-05-23

    The α-glucosidase inhibitory potential of Tribulus terrestris extracts has been reported but as yet the active ingredients are unknown. This study attempted to isolate the responsible metabolites and elucidate their inhibition mechanism of α-glucosidase. By fractionating T. terristris extracts, three cinnamic acid amide derivatives (1-3) were ascertained to be active components against α-glucosidase. The lead structure, N-trans-coumaroyltyramine 1, showed significant inhibition of α-glucosidase (IC50 = 0.42 μM). Moreover, all active compounds displayed uncompetitive inhibition mechanisms that have rarely been reported for α-glucosidase inhibitors. This kinetic behavior was fully demonstrated by showing a decrease of both Km and Vmax, and Kik/Kiv ratio ranging between 1.029 and 1.053. We progressed to study how chemical modifications to the lead structure 1 may impact inhibition. An α, β-unsaturation carbonyl group and hydroxyl group in A-ring of cinnamic acid amide emerged to be critical functionalities for α-glucosidase inhibition. The molecular modeling study revealed that the inhibitory activities are tightly related to π-π interaction as well as hydrogen bond interaction between enzyme and inhibitors. PMID:26974386

  1. The effect of pH on the toxicity of fatty acids and fatty acid amides to rainbow trout gill cells.

    Bertin, Matthew J; Voronca, Delia C; Chapman, Robert W; Moeller, Peter D R

    2014-01-01

    Harmful algal blooms (HABs) expose aquatic organisms to multiple physical and chemical stressors during an acute time period. Algal toxins themselves may be altered by water chemistry parameters affecting their bioavailability and resultant toxicity. The purpose of this study was to determine the effects of two abiotic parameters (pH, inorganic metal salts) on the toxicity of fatty acid amides and fatty acids, two classes of lipids produced by harmful algae, including the golden alga, Prymnesium parvum, that are toxic to aquatic organisms. Rainbow trout gill cells were used as a model of the fish gill and exposed to single compounds and mixtures of compounds along with variations in pH level and concentration of inorganic metal salts. We employed artificial neural networks (ANNs) and standard ANOVA statistical analysis to examine and predict the effects of these abiotic parameters on the toxicity of fatty acid amides and fatty acids. Our results demonstrate that increasing pH levels increases the toxicity of fatty acid amides and inhibits the toxicity of fatty acids. This phenomenon is reversed at lower pH levels. Exposing gill cells to complex mixtures of chemical factors resulted in dramatic increases in toxicity compared to tests of single compounds for both the fatty acid amides and fatty acids. These findings highlight the potential of physicochemical factors to affect the toxicity of chemicals released during algal blooms and demonstrate drastic differences in the effect of pH on fatty acid amides and fatty acids. PMID:24240104

  2. CO2 Solubilities in Amide-based Brφnsted Acidic Ionic Liquids

    A distinguished class of hydrophobic ionic liquids bearing a Brφnsted acidic character derived from amide-like compounds were prepared by a neutralization reaction of N,N-diethylformamide, N,N-dibutylformamide, 1-formylpiperidine, and ε-caprolactam with trifluoroacetic acid and physical absorptions of CO2 in these ionic liquids were demonstrated and evaluated. CO2 solubilities in these ionic liquids were influenced by the molecular structure of the cation and were apparently increased with the molar volume. Comparison based on a volume unit reveals that CO2 solubilities in these liquids are relatively higher than those in imidazolium-based ionic liquids. Henry's coefficients calculated from low-pressure solubility tests at 313 to 333 K were used to derive the thermodynamics quantities. Enthalpy and entropy of solvation may share equal contributions in solubility

  3. Synthesis and Antimicrobial Activities of Amides of Chiral Benzyl Ethers of N-Boc Protected Aminols of L-amino acids with Succinic Acid

    The research work presented in this article describes a synthesis of chiral amides. Chiral benzyl ethers of N-Boc protected aminols reacted with succinic acid using 2,4,6-trichloro-1,3,5-triazine (TCT) as a coupling agent producing chiral amides in high yields. The synthetic amides were investigated for their antifungal and antibacterial activities against different bacterial and fungal strains. All the compounds showed excellent zone of inhibition against the three tested bacterial strains and good to moderate activity against one fungal strain. (author)

  4. Solubility of CO2 in amide-based Brønsted acidic ionic liquids

    Highlights: ► The CO2 solubility in Brønsted acidic ionic liquids (BAIL) has been reported. ► The experimental data were reduced to Henry’s law constants as a function of temperature. ► The Gibbs free energy, enthalpy and entropy changes were calculated. ► Relationship between solubility and molar volumes of BAILs was developed. - Abstract: Several hydrophilic amide-based Brønsted acidic ionic liquids (BAILs) were prepared by simple acid-base neutralization reaction of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methylpyrrolidone (NMP) with trifluoroacetic acid (TFA) or tetrafluoroboric acid (FBA). The solubility data of CO2 in these BAILs were determined at T = (303.15, 313.15, and 323.15) K and subatmospheric pressure using isochoric saturation method. With the same cation, CO2 solubility in TFA-based BAILs was higher than that in FBA-based ones. From the variation of solubility, expressed as Henry’s law constants, with temperature, the standard Gibbs free energy, enthalpy, and entropy changes of CO2 solvation were calculated. The solubilities of CO2 in these BAILs were apparently increased with increasing the molar volume of BAIL except for [DMFH][TFA].

  5. Development of the aza-crown ether metal complexes as artificial hydrolase.

    Yu, Lan; Li, Fang-zhen; Wu, Jiao-yi; Xie, Jia-qing; Li, Shuo

    2016-01-01

    Hydrolases play a crucial role in the biochemical process, which can catalyze the hydrolysis of various compounds like carboxylic esters, phosphoesters, amides, nucleic acids, peptides, and so on. The design of artificial hydrolases has attracted extensive attention due to their scientific significance and potential applications in the field of gene medicine and molecular biology. Numerous macrocyclic metal complexes have been used as artificial hydrolase in the catalytic hydrolysis of the organic substrate. Aza-crown ether for this comment is a special class of the macrocyclic ligand containing both the nitrogen atoms and oxygen atoms in the ring. The studies showed that the aza-crown complexes exhibited high activity of hydrolytic enzyme. However, the aza-crown ether metal complex as artificial hydrolase is still very limited because of its difficulty in synthesis. This review summarizes the development of the aza-crown ether metal complexes as the artificial hydrolase, including the synthesis and catalysis of the transition metal complexes and lanthanide metal complexes of aza-crown ethers. The purpose of this review is to highlight: (1) the relationship between the structure and hydrolytic activity of synthetic hydrolase; (2) the synergistic effect of metal sites and ligands in the course of organic compound hydrolysis; and (3) the design strategies of the aza-crown ethers as hydrolase. PMID:26460062

  6. Complexes of rare-earth perchlorates with ditbutyl amides of di, tri and tetraglycolic acids

    Premlatha, C; Soundararajan, S

    1981-01-01

    New complexes of lanthanide perchlorates with di-t-butyl amides of di, tri and tetraglycolic acids have been synthesised. The complexes have the general formula Ln(DiGA)3(ClO4)3; Ln(TriGA)2 (ClO4)3 and Ln(TetGA)2 (C1O4)3, where Ln = La-Yb and Y and DiGA = N,N′, di-t-butyl diglycolamide, TriGA N,N′, di-t-butyl triglycolamide and TetGA = N,N′ di-t-butyl tetraglycolamide, respectively. The complexes have been characterized by analysis, electrolytic conductance, infrared,1H and13C nuclear magneti...

  7. Amino acid amides of piperic acid (PA) and 4-ethylpiperic acid (EPA) as NorA efflux pump inhibitors of Staphylococcus aureus.

    Wani, Naiem Ahmad; Singh, Samsher; Farooq, Saleem; Shankar, Sudha; Koul, Surrinder; Khan, Inshad Ali; Rai, Rajkishor

    2016-09-01

    A total of eighteen piperic acid (PA) and 4-ethylpiperic acid (EPA) amides (C1-C18) with α-, β- and γ-amino acids were synthesized, characterized and evaluated for their efflux pump inhibitory activity against ciprofloxacin resistant Staphylococcus aureus. The amides were screened against NorA overexpressing S. aureus SA-1199B and wild type S. aureus SA-1199 using ethidium bromide as NorA efflux pump substrate. EPI C6 was found to be most potent and reduced the MIC of ciprofloxacin by 16 fold followed by C18 which showed 4 fold reduction of MIC. Ethidium bromide efflux inhibition and accumulation assay proved these compounds as NorA inhibitors. PMID:27503686

  8. Atom-economic catalytic amide synthesis from amines and carboxylic acids activated in situ with acetylenes

    Krause, Thilo; Baader, Sabrina; Erb, Benjamin; Gooßen, Lukas J.

    2016-01-01

    Amide bond-forming reactions are of tremendous significance in synthetic chemistry. Methodological research has, in the past, focused on efficiency and selectivity, and these have reached impressive levels. However, the unacceptable amounts of waste produced have led the ACS GCI Roundtable to label ‘amide bond formation avoiding poor atom economy' as the most pressing target for sustainable synthetic method development. In response to this acute demand, we herein disclose an efficient one-pot amide coupling protocol that is based on simple alkynes as coupling reagents: in the presence of a dichloro[(2,6,10-dodecatriene)-1,12-diyl]ruthenium catalyst, carboxylate salts of primary or secondary amines react with acetylene or ethoxyacetylene to vinyl ester intermediates, which undergo aminolysis to give the corresponding amides along only with volatile acetaldehyde or ethyl acetate, respectively. The new amide synthesis is broadly applicable to the synthesis of structurally diverse amides, including dipeptides. PMID:27282773

  9. Atom-economic catalytic amide synthesis from amines and carboxylic acids activated in situ with acetylenes.

    Krause, Thilo; Baader, Sabrina; Erb, Benjamin; Gooßen, Lukas J

    2016-01-01

    Amide bond-forming reactions are of tremendous significance in synthetic chemistry. Methodological research has, in the past, focused on efficiency and selectivity, and these have reached impressive levels. However, the unacceptable amounts of waste produced have led the ACS GCI Roundtable to label 'amide bond formation avoiding poor atom economy' as the most pressing target for sustainable synthetic method development. In response to this acute demand, we herein disclose an efficient one-pot amide coupling protocol that is based on simple alkynes as coupling reagents: in the presence of a dichloro[(2,6,10-dodecatriene)-1,12-diyl]ruthenium catalyst, carboxylate salts of primary or secondary amines react with acetylene or ethoxyacetylene to vinyl ester intermediates, which undergo aminolysis to give the corresponding amides along only with volatile acetaldehyde or ethyl acetate, respectively. The new amide synthesis is broadly applicable to the synthesis of structurally diverse amides, including dipeptides. PMID:27282773

  10. Improved annotation of conjugated bile acid hydrolase superfamily members in Gram-positive bacteria

    Lambert, J.M.; Siezen, R.J.; Vos, de W.M.; Kleerebezem, M.

    2008-01-01

    Most Gram-positive bacteria inhabiting the gastrointestinal tract are capable of hydrolysing bile salts. Bile salt hydrolysis is thought to play an important role in various biological processes in the host. Therefore, correct annotation of bacterial bile salt hydrolases (Bsh) in public databases (E

  11. The extraction of uranium (VI) and plutonium (IV) from nitric acid solutions with N,N-dialkyl substituting amides

    The use of N,N-di-2-methylheptyl acetamide (DMHAA),N,N-di-butylbutylamide(DBBA) and N,N-di-butylheptylamide(DBHA) as extractants for the extraction of nitric acid, U(VI) and Pu(IV) from the nitric acid solution has been investigated. The molar ratios of DBHA-HNO3 and DBHA-UO2(NO3)2 complexes are found to be 1:1 and 2:1 respectively. The complexes of both nitric acid and uranyl nitrate with these amides are highly soluble in aromatic diluent such as toluene without any formation of the third phase. The results show that, by modifying the length of the substitute chain and the degree of branch chain, some substituted amides might be found with which U(VI) and Pu(IV) could be co-extracted at moderate nitric acid solution and Pu(IV) could be preferably stripped at low acidity, and the separation of U(VI) and Pu(IV) could be accomplished without reductant of U(VI) and Pu(IV) in amide extraction

  12. Pd-Catalyzed Coupling of γ-C(sp(3))-H Bonds of Oxalyl Amide-Protected Amino Acids with Heteroaryl and Aryl Iodides.

    Han, Jian; Zheng, Yongxiang; Wang, Chao; Zhu, Yan; Huang, Zhi-Bin; Shi, Da-Qing; Zeng, Runsheng; Zhao, Yingsheng

    2016-07-01

    Pd-catalyzed regioselective coupling of γ-C(sp(3))-H bonds of oxalyl amide-protected amino acids with heteroaryl and aryl iodides is reported. A wide variety of iodides are tolerated, giving the corresponding products in moderate to good yields. Various oxalyl amide-protected amino acids were compatible in this C-H transformation, thus representing a practical method for constructing non-natural amino acid derivatives. PMID:27286881

  13. Fatty Acid Amide Hydrolase-Dependent Generation of Antinociceptive Drug Metabolites Acting on TRPV1 in the Brain

    Barriere, David A.; Mallet, Christophe; Blomgren, Anders; Simonsen, Charlotte; Daulhac, Laurence; Libert, Frederic; Chapuy, Eric; Etienne, Monique; Högestätt, Edward; Zygmunt, Peter; Eschalier, Alain

    2013-01-01

    The discovery that paracetamol is metabolized to the potent TRPV1 activator N-(4-hydroxyphenyl)-5Z, 8Z, 11Z, 14Z-eicosatetraenamide (AM404) and that this metabolite contributes to paracetamol's antinociceptive effect in rodents via activation of TRPV1 in the central nervous system (CNS) has provided a potential strategy for developing novel analgesics. Here we validated this strategy by examining the metabolism and antinociceptive activity of the de-acetylated paracetamol metabolite 4-ami...

  14. Synthesis and structure-activity relationship of piperidine-derived non-urea soluble epoxide hydrolase inhibitors

    Pecic, Stevan; Pakhomova, Svetlana; Newcomer, Marcia E.; Morisseau, Christophe; Hammock, Bruce D.; Zhu, Zhengxiang; Rinderspacher, Alison; Deng, Shi-Xian [UCD; (LSU); (Columbia)

    2013-09-27

    A series of potent amide non-urea inhibitors of soluble epoxide hydrolase (sEH) is disclosed. The inhibition of soluble epoxide hydrolase leads to elevated levels of epoxyeicosatrienoic acids (EETs), and thus inhibitors of sEH represent one of a novel approach to the development of vasodilatory and anti-inflammatory drugs. Structure–activities studies guided optimization of a lead compound, identified through high-throughput screening, gave rise to sub-nanomolar inhibitors of human sEH with stability in human liver microsomal assay suitable for preclinical development.

  15. Synthesis of novel nanostructured chiral poly(amide-imide)s containing dopamine and natural amino acids

    Shadpour Mallakpour; Amin Zadehnazari

    2013-01-01

    Four new thermally stable and optically active poly(amide-imide)s (PAI)s with good inherent viscosities were synthesized from the direct polycondensation reaction of N,N'-(pyromellitoyl)-bis-L--amino acids with 3,5-diamino-N-(3,4-dihydroxy-phen-ethyl)benzamide in a medium consisting of a molten salt, tetrabutylammonium bromide, and triphenyl phosphite as the activator. The polymerization reactions produced a series of novel PAIs containing dopamine segment in the side chain in high yield with inherent viscosities between 0.33 and 0.49 dL/g. The obtained polymers were typically characterized by means of FT-IR, 1HNMR spectroscopy, elemental analyses, powder X-ray diffraction, field emission scanning electronmicroscopy, inherent viscosity, and solubility tests. Thermal properties and flame retardant behaviour of the PAIs were also investigated using thermal gravimetric analysis (TGA and DTG) and limiting oxygen index (LOI). Data obtained by thermal analysis revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the obtained polymers were capable of exhibiting good flame retardant properties.

  16. Synthesis, Antifungal Activity and QSAR of Some Novel Carboxylic Acid Amides

    Shijie Du

    2015-03-01

    Full Text Available A series of novel aromatic carboxylic acid amides were synthesized and tested for their activities against six phytopathogenic fungi by an in vitro mycelia growth inhibition assay. Most of them displayed moderate to good activity. Among them N-(2-(1H-indazol-1-ylphenyl-2-(trifluoromethylbenzamide (3c exhibited the highest antifungal activity against Pythium aphanidermatum (EC50 = 16.75 µg/mL and Rhizoctonia solani (EC50 = 19.19 µg/mL, compared to the reference compound boscalid with EC50 values of 10.68 and 14.47 µg/mL, respectively. Comparative molecular field analysis (CoMFA and comparative molecular similarity indices analysis (CoMSIA were employed to develop a three-dimensional quantitative structure-activity relationship model for the activity of the compounds. In the molecular docking, a fluorine atom and the carbonyl oxygen atom of 3c formed hydrogen bonds toward the hydroxyl hydrogens of TYR58 and TRP173.

  17. Characterization of an Indole-3-Acetamide Hydrolase from Alcaligenes faecalis subsp. parafaecalis and Its Application in Efficient Preparation of Both Enantiomers of Chiral Building Block 2,3-Dihydro-1,4-Benzodioxin-2-Carboxylic Acid.

    Pradeep Mishra

    Full Text Available Both the enantiomers of 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid are valuable chiral synthons for enantiospecific synthesis of therapeutic agents such as (S-doxazosin mesylate, WB 4101, MKC 242, 2,3-dihydro-2-hydroxymethyl-1,4-benzodioxin, and N-[2,4-oxo-1,3-thiazolidin-3-yl]-2,3-dihydro-1,4-benzodioxin-2-carboxamide. Pharmaceutical applications require these enantiomers in optically pure form. However, currently available methods suffer from one drawback or other, such as low efficiency, uncommon and not so easily accessible chiral resolving agent and less than optimal enantiomeric purity. Our interest in finding a biocatalyst for efficient production of enantiomerically pure 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid lead us to discover an amidase activity from Alcaligenes faecalis subsp. parafaecalis, which was able to kinetically resolve 2,3-dihydro-1,4-benzodioxin-2-carboxyamide with E value of >200. Thus, at about 50% conversion, (R-2,3-dihydro-1,4-benzodioxin-2-carboxylic acid was produced in >99% e.e. The remaining amide had (S-configuration and 99% e.e. The amide and acid were easily separated by aqueous (alkaline-organic two phase extraction method. The same amidase was able to catalyse, albeit at much lower rate the hydrolysis of (S-amide to (S-acid without loss of e.e. The amidase activity was identified as indole-3-acetamide hydrolase (IaaH. IaaH is known to catalyse conversion of indole-3-acetamide (IAM to indole-3-acetic acid (IAA, which is phytohormone of auxin class and is widespread among plants and bacteria that inhabit plant rhizosphere. IaaH exhibited high activity for 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which was about 65% compared to its natural substrate, indole-3-acetamide. The natural substrate for IaaH indole-3-acetamide shared, at least in part a similar bicyclic structure with 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which may account for high activity of enzyme towards this un-natural substrate. To

  18. Characterization of an Indole-3-Acetamide Hydrolase from Alcaligenes faecalis subsp. parafaecalis and Its Application in Efficient Preparation of Both Enantiomers of Chiral Building Block 2,3-Dihydro-1,4-Benzodioxin-2-Carboxylic Acid.

    Mishra, Pradeep; Kaur, Suneet; Sharma, Amar Nath; Jolly, Ravinder S

    2016-01-01

    Both the enantiomers of 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid are valuable chiral synthons for enantiospecific synthesis of therapeutic agents such as (S)-doxazosin mesylate, WB 4101, MKC 242, 2,3-dihydro-2-hydroxymethyl-1,4-benzodioxin, and N-[2,4-oxo-1,3-thiazolidin-3-yl]-2,3-dihydro-1,4-benzodioxin-2-carboxamide. Pharmaceutical applications require these enantiomers in optically pure form. However, currently available methods suffer from one drawback or other, such as low efficiency, uncommon and not so easily accessible chiral resolving agent and less than optimal enantiomeric purity. Our interest in finding a biocatalyst for efficient production of enantiomerically pure 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid lead us to discover an amidase activity from Alcaligenes faecalis subsp. parafaecalis, which was able to kinetically resolve 2,3-dihydro-1,4-benzodioxin-2-carboxyamide with E value of >200. Thus, at about 50% conversion, (R)-2,3-dihydro-1,4-benzodioxin-2-carboxylic acid was produced in >99% e.e. The remaining amide had (S)-configuration and 99% e.e. The amide and acid were easily separated by aqueous (alkaline)-organic two phase extraction method. The same amidase was able to catalyse, albeit at much lower rate the hydrolysis of (S)-amide to (S)-acid without loss of e.e. The amidase activity was identified as indole-3-acetamide hydrolase (IaaH). IaaH is known to catalyse conversion of indole-3-acetamide (IAM) to indole-3-acetic acid (IAA), which is phytohormone of auxin class and is widespread among plants and bacteria that inhabit plant rhizosphere. IaaH exhibited high activity for 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which was about 65% compared to its natural substrate, indole-3-acetamide. The natural substrate for IaaH indole-3-acetamide shared, at least in part a similar bicyclic structure with 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which may account for high activity of enzyme towards this un-natural substrate. To the best of

  19. Evaluation of unsaturated alkanoic acid amides as maskers of epigallocatechin gallate astringency.

    Obst, Katja; Paetz, Susanne; Backes, Michael; Reichelt, Katharina V; Ley, Jakob P; Engel, Karl-Heinz

    2013-05-01

    Some foods, beverages, and food ingredients show characteristic long-lasting aftertastes. The sweet, lingering taste of high intensity sweeteners or the astringency of tea catechins are typical examples. Epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea, causes a long-lasting astringency and bitterness. These sensations are mostly perceived as aversive and are only accepted in a few foods (e.g., tea and red wine). For the evaluation of the aftertaste of such constituents over a certain period of time, Intensity Variation Descriptive Methodology (IVDM) was used. The approach allows the measurement of different descriptors in parallel in one panel session. IVDM was evaluated concerning the inter- and intraindividual differences of panelists for bitterness and astringency of EGCG. Subsequently, the test method was used as a screening tool for the identification of potential modality-selective masking compounds. In particular, the intensity of the astringency of EGCG (750 mg kg(-1)) could be significantly lowered by 18-33% during the time course by adding the trigeminal-active compound trans-pellitorine (2E,4E-decadienoic acid N-isobutyl amide 1, 5 mg kg(-1)) without significantly affecting bitterness perception. Further, structurally related compounds were evaluated on EGCG to gain evidence for possible structure-activity relationships. A more polar derivative of 1, (2S)-2-[[(2E,4E)-deca-2,4-dienoyl]amino]propanoic acid 9, was also able to reduce the astringency of EGCG similar to trans-pellitorine but without showing the strong tingling effect. PMID:23582039

  20. Synthesis and structural studies of amino amide salts derived from 2-(aminomethyl)benzimidazole and α-amino acids

    Avila-Montiel, Concepción; Tapia-Benavides, Antonio R.; Falcón-León, Martha; Ariza-Castolo, Armando; Tlahuext, Hugo; Tlahuextl, Margarita

    2015-11-01

    2-{[(Ammoniumacetyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 4, 2-{[(2-ammoniumpropanoyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 5, and 2-{[(2-ammonium-3-phenylpropanoyl)amino]methyl}-1H-benzimidazol-3-ium dichloride 6 amino amides were synthesized via condensation of 2AMBZ dihydrochloride with the corresponding amino acid. Compounds 7-12 were obtained by replacing chloride ions (in salts 4-6) with nitrate or tetrachlorozincate ions. The results of X-ray diffraction crystallographic studies indicated that the geometries, charges and sizes of the anions are essential for the formation of the strong hydrogen bond interactions of compounds 4, 5, 9-12. Moreover, in most cases, the presence of water and solvent molecules stabilizes the supramolecular structures of these compounds. Nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy indicated that the presence of chloride or tetrachlorozincate anions increases the acidity of the benzimidazolic and amide groups more significantly than the presence of nitrate anions. However, Quantum Theory of Atoms in Molecules (QTAIM) computations of the crystal structures demonstrate that amino amides interact more strongly with NO3- than with Cl- and ZnCl42- anions; this difference explains the spectroscopic results.

  1. Synthesis, Properties and Applications of Biodegradable Polymers Derived from Diols and Dicarboxylic Acids: From Polyesters to Poly(ester amides

    Angélica Díaz

    2014-04-01

    Full Text Available Poly(alkylene dicarboxylates constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals. Finally, the incorporation of aromatic units and α-amino acids is considered since stiffness of molecular chains and intermolecular interactions can be drastically changed. In fact, poly(ester amides derived from naturally occurring amino acids offer great possibilities as biodegradable materials for biomedical applications which are also extensively discussed.

  2. Synthesis and evaluation of fatty acid amides on the N-oleoylethanolamide-like activation of peroxisome proliferator activated receptor α.

    Takao, Koichi; Noguchi, Kaori; Hashimoto, Yosuke; Shirahata, Akira; Sugita, Yoshiaki

    2015-01-01

    A series of fatty acid amides were synthesized and their peroxisome proliferator-activated receptor α (PPAR-α) agonistic activities were evaluated in a normal rat liver cell line, clone 9. The mRNAs of the PPAR-α downstream genes, carnitine-palmitoyltransferase-1 and mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase, were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) as PPAR-α agonistic activities. We prepared nine oleic acid amides. Their PPAR-α agonistic activities were, in decreasing order, N-oleoylhistamine (OLHA), N-oleoylglycine, Oleamide, N-oleoyltyramine, N-oleoylsertonin, and Olvanil. The highest activity was found with OLHA. We prepared and evaluated nine N-acylhistamines (N-acyl-HAs). Of these, OLHA, C16:0-HA, and C18:1Δ(9)-trans-HA showed similar activity. Activity due to the different chain length of the saturated fatty acid peaked at C16:0-HA. The PPAR-α antagonist, GW6471, inhibited the induction of the PPAR-α downstream genes by OLHA and N-oleoylethanolamide (OEA). These data suggest that N-acyl-HAs could be considered new PPAR-α agonists. PMID:25832022

  3. Gene evolution of epoxide hydrolases and recommended nomenclature

    Beetham, J K; Grant, D; Arand, M; Garbarino, J; Kiyosue, T; Pinot, F; Oesch, F; Belknap, W R; Shinozaki, K.; Hammock, B. D.

    1995-01-01

    We have analyzed amino acid sequence relationships among soluble and microsomal epoxide hydrolases, haloacid dehalogenases, and a haloalkane dehalogenase. The amino-terminal residues (1-229) of mammalian soluble epoxide hydrolase are homologous to a haloacid dehalogenase. The carboxy-terminal residues (230-554) of mammalian soluble epoxide hydrolase are homologous to haloalkane dehalogenase, to plant soluble epoxide hydrolase, and to microsomal epoxide hydrolase. The shared identity between t...

  4. Influence of physico-chemical parameters of some barbituric acid derivatives on their retention on an amide embedded RP silica column.

    Jakab, Annamaria; Prodan, Miklos; Forgács, Esther

    2002-03-01

    Retention parameters of 45 different barbituric acid derivatives were determined on an amide embedded RP silica column (Discovery RP-AmideC16) using non-buffered water-acetonitrile eluent systems. Linear correlation were calculated between the logarithm of the capacity factor and the acetonitrile concentration in the eluent. To determine the retention behavior of barbituric acid derivatives, stepwise regression analysis (SRA) and principal component analysis (PCA) followed by two-dimensional nonlinear and modified nonlinear mapping was used. It can be concluded, the retention of barbituric acid derivatives are governed mainly by the steric parameters of the substituents. Principal component analysis indicated that the barbituric acid derivatives have mixed retention on this amide embedded RP silica column in water-acetonitrile eluent. PMID:11836055

  5. Synthesis of [14C]-labelled eicosa-5,8,11-triynoic acid and conversion to anti-inflammatory amides

    A four step synthesis of [5,6-14C]-eicosa-5,8,11-triynoic acid from [14C]-labelled acetylene is described. [14C2]-acetylene was converted to 5-chloro-[1,2-14C]-pentyne via reaction of its monolithium salt with 3-bromo-1-chloropropane. The doubly labelled 5-chloropentyne thus obtained was transformed to [5,6-14C]-hex-5-ynoic acid which was then coupled with 1-chloro-tetradeca-2,5-diyne to give the title compound. Using 2-(2-aminoethoxy)ethanol and 1-(2-hydroxyethyl)piperazine, amides which had previously been found to be potent inhibitors of the 5-lipoxygenase enzyme, were prepared from [14C-labelled eicosatriynoic acid by way of acylimidazole chemistry. (author)

  6. IR-spectra of amides of steroidal alkaloids with lactic acid

    Kastelic-Suhadolc, Tatjana

    2015-01-01

    IR spectra of lactamides of 1,4-tomatidien-3-one, 4-solasoden-3-one, dihydrotomatidine and tomatine were taken and the frequency of the ▫$C=0$▫ amide band compared with that of the lactamides of piperidine and its derivatives, and with that of N-acetyltomatidine. It was found that the ▫$C=0$▫ bands of lactamides of steroidal alkaloids show an unusual but characteristic frequency at 1730-1733 cm▫$^{-1}$▫.

  7. Cysteine amide adduct formation from carboxylic acid drugs via UGT-mediated bioactivation in human liver microsomes.

    Harada, H; Toyoda, Y; Endo, T; Kobayashi, M

    2015-10-01

    Although chemical trapping has been widely used to evaluate cytochrome P450-mediated drug bioactivation, thus far, only a few in vitro-trapping studies have been performed on UDP-glucuronosyltransferase (UGT)-mediated drug bioactivation. In this study, we used cysteine (Cys) as trapping agent to gain new insights into the UGT-mediated bioactivation involving acyl glucuronides of carboxylic acid drugs. Diclofenac, ketoprofen and ibuprofen were incubated in human liver microsomes with UDPGA and Cys, followed by analysis using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The N-acyl-Cys amide adduct of diclofenac was characterized by mass analysis and was detectable even in photodiode array analysis. Our data indicated that the formation of such adducts reflects the reactivity of the corresponding acyl glucuronides. In addition, it was suggested that the adduct formation requires an N-terminal Cys moiety with both a free amine and a free thiol group, from the results using various cysteine derivatives. We propose that the S-acyl-Cys thioester adduct can form via transacylation of an acyl glucuronide and can then form to an N-acyl-Cys amide adduct through intramolecular S- to N-acyl rearrangement. This series of the reactions has important implications as a possible bioactivation mechanism for covalent binding of carboxylic acid drugs to macromolecules. PMID:26601426

  8. Amides as phase modifiers for N,N'-tetraalkylmalonamide extraction of actinides and lanthanides from nitric acid solutions

    The N,N'-tetraalkylmalonamides are a class of compounds under development for transuranic (TRU) separations under high nitric acid conditions. There are several issues that challenge the further development of these ligands. One is the development of improved synthetic procedures that lend themselves to commercial scale-up. Another major issue is the third-phase formation that occurs when the N,N'-tetraalkylmalonamides are contacted with medium-to-high nitric acid concentrations in hydrocarbon solvents. To address the synthesis issue, the authors have developed a new synthetic approach for preparing these materials. Third-phase formation can be eliminated by addition of diluent modifiers such as tributylphosphate (TBP). TBP is inappropriate if a nonphosphate-containing process stream is required. Amides have been proposed as alternatives for TBP in a variety of applications because of their ease of synthesis and the variety of substituents that can be generated. The authors have been able to develop an amide phase-modified system that extends the working process range of alkylinalonamides (0.5 M) in dodecane: from 3.5 M to 7.5 M nitric acid and in Isopar H (branched hydrocarbon) from 4.0 M to 10.0 M nitric acid using 1.0 M di-2-ethylhexylacetamide/0.5 M alkylmalonamide. The Kd values were comparable to extraction with alkylinalonamide in Isopar H or hydrogenated tetrapropylene (TPH) solvents. The overall extraction system was more robust than the phase-uninodified system allowing for greater temperature and acid concentration fluctuations without third-phase formation

  9. Palladium-catalyzed C–N and C–O bond formation of N-substituted 4-bromo-7-azaindoles with amides, amines, amino acid esters and phenols

    Rajendra Surasani

    2012-11-01

    Full Text Available Simple and efficient procedures for palladium-catalyzed cross-coupling reactions of N-substituted 4-bromo-7-azaindole (1H-pyrrole[2,3-b]pyridine, with amides, amines, amino acid esters and phenols through C–N and C–O bond formation have been developed. The C–N cross-coupling reaction of amides, amines and amino acid esters takes place rapidly by using the combination of Xantphos, Cs2CO3, dioxane and palladium catalyst precursors Pd(OAc2/Pd2(dba3. The combination of Pd(OAc2, Xantphos, K2CO3 and dioxane was found to be crucial for the C–O cross-coupling reaction. This is the first report on coupling of amides, amino acid esters and phenols with N-protected 4-bromo-7-azaindole derivatives.

  10. Epoxy fatty acids and inhibition of the soluble epoxide hydrolase selectively modulate GABA mediated neurotransmission to delay onset of seizures.

    Bora Inceoglu

    Full Text Available In the brain, seizures lead to release of large amounts of polyunsaturated fatty acids including arachidonic acid (ARA. ARA is a substrate for three major enzymatic routes of metabolism by cyclooxygenase, lipoxygenase and cytochrome P450 enzymes. These enzymes convert ARA to potent lipid mediators including prostanoids, leukotrienes and epoxyeicosatrienoic acids (EETs. The prostanoids and leukotrienes are largely pro-inflammatory molecules that sensitize neurons whereas EETs are anti-inflammatory and reduce the excitability of neurons. Recent evidence suggests a GABA-related mode of action potentially mediated by neurosteroids. Here we tested this hypothesis using models of chemically induced seizures. The level of EETs in the brain was modulated by inhibiting the soluble epoxide hydrolase (sEH, the major enzyme that metabolizes EETs to inactive molecules, by genetic deletion of sEH and by direct administration of EETs into the brain. All three approaches delayed onset of seizures instigated by GABA antagonists but not seizures through other mechanisms. Inhibition of neurosteroid synthesis by finasteride partially blocked the anticonvulsant effects of sEH inhibitors while the efficacy of an inactive dose of neurosteroid allopregnanolone was enhanced by sEH inhibition. Consistent with earlier findings, levels of prostanoids in the brain were elevated. In contrast, levels of bioactive EpFAs were decreased following seizures. Overall these results demonstrate that EETs are natural molecules which suppress the tonic component of seizure related excitability through modulating the GABA activity and that exploration of the EET mediated signaling in the brain could yield alternative approaches to treat convulsive disorders.

  11. Preparation and surface active properties of oxypropylated diol monoesters of fatty acids with an amide oxime terminal group

    Eissa, A. M.F.

    1994-10-01

    Full Text Available Locally produced non-edible oil, namely, rice bran oil (R.B.O. was utilized as starting materials for preparing new nonionic surfactant. Oxypropylated diol monoesters of linoleic and rice bran oil fatty acids were prepared. Also amide oxime derivatives were obtained. Surface active properties of these compounds were measured. Under neutral condition amide eximes served as nonionic surfactants and their properties were similar to other oxypropylated monoesters.

    Se ha utilizado un aceite no comestible de producción local, denominado, aceite de salvado de arroz (R.B.O. como materia prima para la preparación de nuevos tensioactivos no iónicos. Se prepararon diol monoésteres oxipropilados de ácido linoleico y ácidos grasos de aceite de salvado de arroz. También se obtuvieron los derivados de amido oxima. Se midieron las propiedades de tensión superficial de estos compuestos. Bajo condiciones neutras las amido eximas sirvieron como tensioactivos no iónicos y sus propiedades fueron similares a los de otros monoésteres oxipropilados.

  12. In vitro activity of pipecolic acid amide of clindamycin (U-57930E) on anaerobic bacteria compared with those of clindamycin, cefoxitin, and chloramphenicol.

    Dhawan, V K; Bansal, M B; Thadepalli, H

    1982-01-01

    In vitro activity of pipecolic acid amide of clindamycin (U-57930E) against 265 isolates of anaerobic bacteria, including 66 strains of Bacteroides fragilis, was compared with those of clindamycin, chloramphenicol, and cefoxitin. At therapeutically achievable concentrations, the activities of all four antibiotics against anaerobic bacteria were similar.

  13. Detection and qualitative analysis of fatty acid amides in the urine of alcoholics using HPLC-QTOF-MS.

    Dabur, Rajesh; Mittal, Ashwani

    2016-05-01

    Fatty acid amides (FAAs) in alcoholism lead to liver diseases. These amides have been reported in plasma and in other organs of the body, while their detection or presence in the urine is still unknown. Therefore, the focus of the current study was to detect and analyze FAAs qualitatively in urine samples of alcoholics. Furthermore, the effects of Tinospora cordifolia (hepatoprotective medicinal plant) intervention on FAA levels in moderate alcoholics were also analyzed. In the study, asymptomatic chronic alcoholics (n = 22) without chronic liver disease and nonalcoholic healthy volunteers (n = 24) with a mean age of 39 ± 2.0 years were selected. The first-pass urine and fasting blood samples were collected in the morning on day 0 and day 14 after T. cordifolia water extract (TCE) treatment and analyzed using automated biochemistry analyzer and HPLC-QTOF-MS. Results indicated the increased levels of serum triglycerides, cholesterol, and liver function enzymes in alcoholic subjects, which were significantly down-regulated by TCE intervention. Multivariate discrimination analysis of QTOF-MS data showed increased urinary levels of oleoamide (2.55-fold), palmitamide (5.6-fold), and erucamide (1.6-fold) in alcoholics as compared to control subjects. Levels of oleamide (1.8-fold), palmitamide (1.7-fold), and linoleamide (1.5-fold) were found to be increased in plasma. Treatment with TCE in alcoholics (3.0 g lyophilized water extract/day) significantly decreased the plasma and urinary levels of all FAAs except linoleamide. The HPLC-QTOF-MS approach for FAAs analysis in both urinary and plasma samples of alcoholics worked very well. Moreover, findings (i.e., increased levels of FAAs in urine and in plasma) further support other findings that these amides play a very important role in alcoholism. Further, like our previous findings, TCE proved its hepatoprotective effect against alcoholism not only by lowering the levels of these detected FAAs, but also by decreasing the

  14. Synthesis of the Amide Derivatives of 3-[1-(3-Pyridazinyl)-5-phenyl-1H-pyrazole-3-yl]propanoic Acids as Potential Analgesic Compounds

    BANOĞLU, Erden; Şüküroğlu, Murat; ERGÜN, Burcu ÇALIŞKAN

    2007-01-01

    A series of structurally diverse amide derivatives of 3-[1-(3-pyridazinyl)-5-phenyl-1H-pyrazole-3-yl]propanoic acids were prepared and tested for their in vivo analgesic activity using an acetic acid induced writhing test. All the test compounds displayed approximately equipotent analgesic activity to aspirin. The results showed that the analgesic activity of 5a, 5f, 5n, and 5o is significantly higher than that of 5d.

  15. New optically active poly(amide-imide)s based on N,N '-(pyromellitoyl)-bis-L-amino acid and methylene diphenyl-4,4 '-diisocyanate

    Tian, Xiaoyu; Yao, Jinshui; Zhang, Xian;

    2014-01-01

    Five new optically active poly(amide-imide)s were synthesized through the direct polycondensation reaction between chiral N,N-(pyromellitoyl)-bis-L-amino acids and methylene diphenyl-4,4-diisocyanate in a medium consisting of N-methyl-2-pyrrolidone (NMP) and xylene. The resulted polymers were ful......,N-dimethyl formamide, dimethyl sulfoxide (DMSO), NMP, sulfuric acid, and para-methyl phenol. Same specific rotations of these polymers in these different solvents were obtained....

  16. Relationship between chromatographic resolution and amide structure of chiral 2-hydroxy acids as O-(-)-menthoxycarbonylated diastereomeric derivatives for enantiomeric separation on achiral gas chromatography.

    Cha, Eunju; Kim, Sohee; Lee, Kang Mi; Kim, Ho Jun; Kim, Ki Hun; Kwon, Oh-Seung; Park, Ki Duk; Lee, Jaeick

    2016-02-15

    The relationship between chromatographic resolution and amide structure of chiral 2-hydroxy acids as O-(-)-menthoxycarbonylated diastereomeric derivatives on achiral gas chromatography was investigated to elucidate the best diastereomeric conformation for enantiomeric separation of chiral 2-hydroxy acids. Thirteen chiral 2-hydroxy acids were converted into nine different diastereomeric O-(-)-menthoxycarbonylated amide derivatives using the primary, secondary and cyclic amines to achieve complete enantiomeric separation through an achiral column. Each enantiomeric pair of 2-hydroxy acids as O-(-)-menthoxycarbonylated tert-butylamide derivatives was resolved on both the DB-5 and DB-17 columns with resolution factors ranging from 1.7 to 4.8 and 1.7 to 3.4, respectively. The results revealed that the structure of the amide moiety is shown to significantly affect chromatographic resolution. In addition, O-(-)-menthoxycarbonylated tert-butylamide derivatives were shown to be the best diastereomeric conformations for enantiomeric separation of 2-hydroxy acids. When comparing with our previous O-trifluoroacetylated(-)-menthyl ester derivatization method, the present results suggested that size differences between groups attached to the chiral center and conformational rigidity can have stronger effects on resolution than the distance between chiral centers. The elution of R- and S-stereoisomers was affected by the class of amine; i.e., primary, secondary, or cyclic, regardless of the substituents on the amine group, the structure of the 2-hydroxy acid, and the polarity of the column. PMID:26800225

  17. Efficacy of boswellic acid on lysosomal acid hydrolases, lipid peroxidation and anti-oxidant status in gouty arthritic mice

    Evan Prince Sabina; Haridas Indu; Mahaboobkhan Rasool

    2012-01-01

    Objective:To evaluate the efficacy of boswellic acid against monosodium urate crystal-induced inflammation in mice. Methods:The mice were divided into four experimental groups. Group I served as control;mice in group II were injected with monosodium urate crystal;group III consisted of monosodium urate crystal-induced mice who were treated with boswellic acid (30 mg/kg/b.w.);group IV comprised monosodium urate crystal-induced mice who were treated with indomethacin (3 mg/kg/b.w.). Paw volume and levels/activities of lysosomal enzymes, lipid peroxidation, anti-oxidant status and inflammatory mediator TNF-αwere determined in control and monosodium urate crystal-induced mice. In addition, the levels of β-glucuronidase and lactate dehydrogenase were also measured in monosodium urate crystal-incubated polymorphonuclear leucocytes (PMNL) in vitro. Results:The activities of lysosomal enzymes, lipid peroxidation, and tumour necrosis factor-αlevels and paw volume were increased significantly in monosodium urate crystal-induced mice, whereas the activities of antioxidant status were in turn decreased. However, these changes were modulated to near normal levels upon boswellic acid administration. In vitro, boswellic acid reduced the level of β-glucuronidase and lactate dehydrogenase in monosodium urate crystal-incubated PMNL in concentration dependent manner when compared with control cells. Conclusions: The results obtained in this study further strengthen the anti-inflammatory/antiarthritic effect of boswellic acid, which was already well established by several investigators.

  18. Synthesis and characterization of new optically active copoly(amid-imide)s based on N-phthalimido-L-aspartic acid and aromatic diamines

    Khalil; Faghihi; Hamidreza; Alimohammadi

    2010-01-01

    In this article,six new optically active copoly(amide-imide)s(10a-f) were synthesized through the direct polycondensation reaction of N-phthalimido-L-aspartic acid(4) with 1,5-diamino naphthalene(8),3,4-diamino benzophenone(9) in the presence of therphthahc acid(7),fumaric acid(6) and adipic acid(5) as a second diacid in a medium consisting of N-methyl-2-pyrrolidone,triphenyl phosphite, calcium chloride and pyridine.The resulting copolymers were fully characterized by means of FT-IR spectroscopy,elementa...

  19. Role of amidation in bile acid effect on DNA synthesis by regenerating mouse liver.

    Barbero, E R; Herrera, M C; Monte, M J; Serrano, M A; Marin, J J

    1995-06-01

    Effect of bile acids on DNA synthesis by the regenerating liver was investigated in mice in vivo after partial hepatectomy (PH). Radioactivity incorporation into DNA after [14C]thymidine intraperitoneal administration peaked at 48 h after PH. At this time a significant taurocholate-induced dose-dependent reduction in DNA synthesis without changes in total liver radioactivity content was found (half-maximal effect at approximately 0.1 mumol/g body wt). Effect of taurocholate (0.5 mumol/g body wt) was mimicked by chocolate, ursodeoxycholate, deoxycholate, dehydrocholate, tauroursodeoxycholate, taurochenodeoxycholate, and taurodeoxycholate. In contrast, chenodeoxycholate, glycocholate, glycochenodeoxycholate, glycoursodeoxycholate, glycodeoxycholate, 5 beta-cholestane, bromosulfophthalein, and free taurine lacked this effect. No relationship between hydrophobic-hydrophilic balance and inhibitory effect was observed. Analysis by high-performance liquid chromatography indicated that inhibition of thymidine incorporation into DNA was not accompanied by an accumulation of phosphorylated DNA precursors in the liver but rather by a parallel increase in nucleotide catabolism. Bile acid-induced modifications in DNA synthesis were observed in vivo even in the absence of changes in toxicity tests, which suggests that the inhibitory effect shared by most unconjugated and tauroconjugated bile acids but not by glycoconjugated bile acids should be accounted for by mechanisms other than nonselective liver cell injury. PMID:7611405

  20. New co-crystal and salt form of sulfathiazole with carboxylic acid and amide

    Ranita Samanta; Shipra Kanaujia; C Malla Reddy

    2014-09-01

    One co-crystal and one salt of an antibacterial drug sulfathiazole with 4-aminobenzamide and 2,4-dinitrobenzoic acid have been synthesized. These new forms are characterized by single crystal X-ray diffraction, infrared spectroscopy, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In solid state, sulfathiazole preferentially adopts the imidine tautomeric form.

  1. Selective separation of uranium(VI) on a chelating styrene-DVB based resin containing quinaldinic acid amide group

    A new chelating styrene-DVB based resin containing quinaldinic acid amide functional group, has been synthesised and characterised. The sorption patterns of Na(I), K(I), Be(II), Ca(II), Mg(II), Zn(II), Cd(II), Cu(II), Pb(II), Ni(II), Bi(III), Fe(III), Ti(IV) and U(VI) have been studied as a function of pH. The resin sorbs U(VI) over a wide range of pH (1.0 to 4.0) with a maximum sorption of 0.32 mmol/g at pH 3.5 to 4.0. Zn(II), Cd(II), Cu(II), Na(II), Pb(II), Fe(III) and Ti(IV) are also sorbed to different extents by the resin while Na(I), K(I), Be(II), Ca(II), Mg(II) and Bi(III) are not sorbed. Conditions for separation of U(VI) from these metal ions have been identified. The eluting agent used for U(VI) is 3 N HNO3 and the recovery recorded is about 99.9 per cent (author). 12 refs., 3 tabs

  2. Calix[6]arene bearing carboxylic acid and amide groups in polymeric CTA membrane

    Calix[6]arene having both carboxylic acid (1,3,5-) and carboxamide (2,4,6-) in an alternative way was synthesized. Transport rates of alkali and alkaline-earth metal ions were tested in bulk liquid membrane and polymer inclusion membrane. Ba2+ ion was found to give the highest transport rate among tested metal ions in both BLM and PIM system. In PIM system, high durability (longer than 30 days) of the membrane was observed

  3. Brucella abortus choloylglycine hydrolase affects cell envelope composition and host cell internalization.

    María Inés Marchesini

    Full Text Available Choloylglycine hydrolase (CGH, E.C. 3.5.1.24 is a conjugated bile salt hydrolase that catalyses the hydrolysis of the amide bond in conjugated bile acids. Bile salt hydrolases are expressed by gastrointestinal bacteria, and they presumably decrease the toxicity of host's conjugated bile salts. Brucella species are the causative agents of brucellosis, a disease affecting livestock and humans. CGH confers Brucella the ability to deconjugate and resist the antimicrobial action of bile salts, contributing to the establishment of a successful infection through the oral route in mice. Additionally, cgh-deletion mutant was also attenuated in intraperitoneally inoculated mice, which suggests that CGH may play a role during systemic infection other than hydrolyzing conjugated bile acids. To understand the role CGH plays in B. abortus virulence, we infected phagocytic and epithelial cells with a cgh-deletion mutant (Δcgh and found that it is defective in the internalization process. This defect along with the increased resistance of Δcgh to the antimicrobial action of polymyxin B, prompted an analysis of the cell envelope of this mutant. Two-dimensional electrophoretic profiles of Δcgh cell envelope-associated proteins showed an altered expression of Omp2b and different members of the Omp25/31 family. These results were confirmed by Western blot analysis with monoclonal antibodies. Altogether, the results indicate that Brucella CGH not only participates in deconjugation of bile salts but also affects overall membrane composition and host cell internalization.

  4. Separation and recovery of palladium from acidic waste using dithiodiglycol-amide encapsulated polymeric beads

    Palladium selective ligand, N,N,N',N'-tetra-(2-ethylhexyl)-dithiodiglycolamide (DTDGA), was encapsulated in polymeric composite beads under simple laboratory conditions. The composite beads were evaluated for separation and recovery of palladium from acidic aqueous waste. The beads showed maximum uptake of Pd at 3.0 M HCl. Pd sorption kinetics was found to be fast and, the kinetics data fits well in to the pseudo second-order equation model for the sorption of palladium ions onto the composite beads. Different sorption isotherm models were applied to the experimental data. Equilibrium data are represented well by the Langmuir isotherm equation, with a monolayer sorption capacity of 1.56 mg/g for the swollen beads. Batch extraction studies showed negligible uptake of Fe, Cr, Ni, and Pt, thus showing very high selectivity and extractability of the composite beads for palladium. (author)

  5. A study of fragmentation of protonated amides of some acylated amino acids by tandem mass spectrometry: observation of an unusual nitrilium ion.

    Talaty, Erach R; Young, Sarah M; Dain, Ryan P; Van Stipdonk, Michael J

    2011-05-15

    A tandem mass spectrometric study of a series of secondary amides of acetylglycine and hippuric acid utilizing electrospray ionization (ESI) was conducted. Among the fragment ions observed was an unusual one, which we have determined to be a nitrilium ion having the structure CH3-C≡N⊕-Ph or Ph-C≡N⊕-Ph by loss of the full mass of glycine as a neutral fragment. A mechanism that we propose involves an initial protonation of the oxygen atom at the N-terminus, followed by cyclization to a five-membered imidazolium ring, and its subsequent collapse to the nitrilium ion. This mechanism is supported by extensive isotopic labels and considerable variation of substituents. A similar study of the amides of acyl β-alanine and acyl γ-aminobutyric acid revealed that the former furnishes the same nitrilium ion, but not the latter. Thus, a six-membered intermediate is also possible and capable of losing the full mass of β-alanine as a neutral fragment. When the size of the ring is forced to be seven-membered, this pathway is blocked. When this study was expanded to include a variety of N-acylproline amides, the nitrilium ion was observed in 100% abundance only when the acyl group was acetyl. Thus a proline effect (involvement of a strained bicyclic [3.3.0] structure) is being observed. PMID:21488111

  6. Preparation of different amides via Ritter reaction from alcohols and nitriles in the presence of silica-bonded N- propyl sulphamic acid (SBNPSA) under solvent-free conditions

    Maryam-Sadat Shakeri; Hassan Tajik; Khodabakhsh Niknam

    2012-09-01

    A number of methods have been proposed for the modification of the Ritter reaction. However, many of these methods involve the use of strongly acidic conditions, stoichiometric amounts of reagents, harsh reaction conditions and extended reaction times. Therefore, the development of mild, efficient, convenient and benign reagents for the Ritter reaction is desirable. In this research, we have developed a clean and environmentally friendly protocol for the synthesis of amides by using different benzylic or tertiary alcohols and different nitriles in the presence of silica-bonded N- propyl sulphamic acid (SBNPSA) as catalyst under solvent-free conditions in high yields.

  7. Electrospun Scaffolds from Low Molecular Weight Poly(ester amides Based on Glycolic Acid, Adipic Acid and Odd or Even Diamines

    Sara Keiko Murase

    2015-05-01

    Full Text Available Electrospinning of regular poly(ester amides (PEAs constituted by glycolic acid, adipic acid and diamines with five and six carbon atoms has been carried out. Selected PEAs were constituted by natural origin products and could be easily prepared by a polycondensation method that avoids tedious protection and deprotection steps usually required for obtaining polymers with a regular sequence. Nevertheless, the synthesis had some limitations that mainly concerned the final low/moderate molecular weight that could be attained. Therefore, it was considered interesting to evaluate if electrospun scaffolds could still be prepared taking also advantage of the capability of PEAs to establish intermolecular hydrogen bonds. Results indicated that the crucial factor was the control of polymer concentration in the electrospun solution, being necessary that this concentration was higher than 40% (w/v. The PEA with the lowest molecular weight (Mw close to 8000 g/mol was the most appropriate to obtain electrospun samples with a circular cross-section since higher molecular sized polymers show solvent retention problems derived from the high viscosity of the electrospun solution that rendered ribbon-like morphologies after the impact of fibers into the collector. The studied PEAs were semicrystalline and biodegradable, as demonstrated by calorimetric and degradation studies. Furthermore, the new scaffolds were able to encapsulate drugs with anti-inflammatory and bacteriostatic activities like ketoprofen. The corresponding release and bactericide activity was evaluated in different media and against different bacteria. Finally, biocompatibility was demonstrated using both fibroblast and epithelial cell lines.

  8. Zinc(II) complexes with heterocyclic ether, acid and amide. Crystal structure, spectral, thermal and antibacterial activity studies

    Jabłońska-Wawrzycka, Agnieszka; Rogala, Patrycja; Czerwonka, Grzegorz; Hodorowicz, Maciej; Stadnicka, Katarzyna

    2016-02-01

    The reaction of zinc salts with heterocyclic ether (1-ethoxymethyl-2-methylimidazole (1-ExMe-2-MeIm)), acid (pyridine-2,3-dicarboxylic acid (2,3-pydcH2)) and amide (3,5-dimethylpyrazole-1-carboxamide (3,5-DMePzCONH2)) yielded three new zinc complexes formulated as [Zn(1-ExMe-2-MeIm)2Cl2] 1, fac-[Zn(H2O)6][Zn(2,3-pydcH)3]22 and [Zn(3,5-DMePz)2(NCO)2] 3. Complexes of 1 and 3 are four-coordinated with a tetrahedron as coordination polyhedron. However, compound 2 forms an octahedral cation-anion complex. The complex 3 was prepared by eliminating of the carboxamide group from the ligand and then the 3,5-dimethylpyrazole (3,5-DMePz) and isocyanates formed were employed as new ligands. The IR and X-ray studies have confirmed a bidentate fashion of coordination of the 2,3-pydcH and monodentate fashion of coordination of the 1-ExMe-2-MeIm and 3,5-DMePz to the Zn(II) ions. The crystal packing of Zn(II) complexes are stabilized by intermolecular classical hydrogen bonds of O-H⋯O and N-H⋯O types. The most interesting feature of the supramolecular architecture of complexes is the existence of C-H⋯O, C-H⋯Cl and C-H⋯π interactions and π⋯π stacking, which also contributes to structural stabilisation. The correlation between crystal structure and thermal stability of zinc complexes is observed. In all compounds the fragments of ligands donor-atom containing go in the last steps. Additionally, antimicrobial activities of compounds were carried out against certain Gram-positive and Gram-negative bacteria and counts of CFU (colony forming units) were also determined. The achieved results confirmed a significant antibacterial activity of some tested zinc complexes. On the basis of the Δ log CFU values the antibacterial activity of zinc complexes follows the order: 3 > 2 > 1. Influence a number of N-donor atoms in zinc environment on antibacterial activity is also observed.

  9. Cholesterol-Lowering Potentials of Lactic Acid Bacteria Based on Bile-Salt Hydrolase Activity and Effect of Potent Strains on Cholesterol Metabolism In Vitro and In Vivo

    Cheng-Chih Tsai

    2014-01-01

    Full Text Available This study collected different probiotic isolates from animal and plant sources to evaluate the bile-salt hydrolase activity of probiotics in vitro. The deconjugation potential of bile acid was determined using high-performance liquid chromatography. HepG2 cells were cultured with probiotic strains with high BSH activity. The triglyceride (TG and apolipoprotein B (apo B secretion by HepG2 cells were evaluated. Our results show that the BSH activity and bile-acid deconjugation abilities of Pediococcus acidilactici NBHK002, Bifidobacterium adolescentis NBHK006, Lactobacillus rhamnosus NBHK007, and Lactobacillus acidophilus NBHK008 were higher than those of the other probiotic strains. The cholesterol concentration in cholesterol micelles was reduced within 24 h. NBHK007 reduced the TG secretion by 100% after 48 h of incubation. NBHK002, NBHK006, and NBHK007 could reduce apo B secretion by 33%, 38%, and 39%, respectively, after 24 h of incubation. The product PROBIO S-23 produced a greater decrease in the total concentration of cholesterol, low-density lipoprotein, TG, and thiobarbituric acid reactive substance in the serum or livers of hamsters with hypercholesterolemia compared with that of hamsters fed with a high-fat and high-cholesterol diet. These results show that the three probiotic strains of lactic acid bacteria are better candidates for reducing the risk of cardiovascular disease.

  10. Molecular cloning and sequence analysis of complementary DNA encoding rat mammary gland medium-chain S-acyl fatty acid synthetase thio ester hydrolase

    Poly(A) + RNA from pregnant rat mammary glands was size-fractionated by sucrose gradient centrifugation, and fractions enriched in medium-chain S-acyl fatty acid synthetase thio ester hydrolase (MCH) were identified by in vitro translation and immunoprecipitation. A cDNA library was constructed, in pBR322, from enriched poly(A) + RNA and screened with two oligonucleotide probes deduced from rat MCH amino acid sequence data. Cross-hybridizing clones were isolated and found to contain cDNA inserts ranging from ∼ 1100 to 1550 base pairs (bp). A 1550-bp cDNA insert, from clone 43H09, was confirmed to encode MCH by hybrid-select translation/immunoprecipitation studies and by comparison of the amino acid sequence deduced from the DNA sequence of the clone to the amino acid sequence of the MCH peptides. Northern blot analysis revealed the size of the MCH mRNA to be 1500 nucleotides, and it is therefore concluded that the 1550-bp insert (including G x C tails) of clone 43H09 represents a full- or near-full-length copy of the MCH gene. The rat MCH sequence is the first reported sequence of a thioesterase from a mammalian source, but comparison of the deduced amino acid sequences of MCH and the recently published mallard duck medium-chain S-acyl fatty acid synthetase thioesterase reveals significant homology. In particular, a seven amino acid sequence containing the proposed active serine of the duck thioesterase is found to be perfectly conserved in rat MCH

  11. Aminocarbonylation of 4-iodo-1H-imidazoles with an amino acid amide nucleophile: synthesis of constrained H-Phe-Phe-NH2 analogues.

    Skogh, Anna; Fransson, Rebecca; Sköld, Christian; Larhed, Mats; Sandström, Anja

    2013-12-01

    A simple and an expedient process to prepare 5-aryl-1-benzyl-1H-imidazole-4-carboxamides by the aminocarbonylation of 5-aryl-4-iodo-1H-imidazoles using ex situ generation of CO from Mo(CO)6 with an amino acid amide nucleophile is reported. Furthermore, a microwave-assisted protocol for the direct C-5 arylation of 1-benzyl-1H-imidazole and a regioselective C-4 iodination method to acquire starting material for our aminocarbonylation are presented. The method can be used to prepare imidazole based peptidomimetics, herein exemplified by the synthesis of constrained H-Phe-Phe-NH2 analogues. PMID:24171628

  12. Extraction of Np(IV), Np(VI), Pu(IV) and U(VI) with amides, BEHSO and CMPO from nitric acid medium

    The extraction of Np(IV), Np(VI), Pu(IV) and U(VI) from a nitric acid medium has been carried out with dibutyldecanamide (DBDA), dihexyldecanamide (DHDA), bis-2-ethylhexylsulphoxide (BEHSO) and octyl(phenyl)-N-N-diisobutyl-carbamolymethylphosphine oxide (CMPO) using n-dodecane as the diluent. The order of extraction for the metal ions is CMPO>BEHSO>DHDA>DBDA. The species extracted into the organic phase was found to be the disolvate with all the extractants while using hexavalent metal ions Np(VI) and U(VI) and also with tetravalent ions Np(IV) and Pu(IV) in the case of BEHSO and CMPO. However, in the case of DBDA and DHDA, Np(IV) and Pu(IV) were extracted as the trisolvate species. The equilibrium constant (K) for the formation of the above species has been evaluated after applying the possible correction factors. In general, logK increases with increasing basicity of the extractants. In the case of amides, the plot of logK verses kH (acid uptake equilibrium constant) gave straight lines which could be represented by the empirical equation: logKU(VI)=5.17 kH+0.18 and logKPu(IV)=3.11 kH+1.81 for the respective metal ions. With the help of these empirical equations it is possible to predict the equilibrium constant values of amide complexes of U(VI) or Pu(IV) if the kH values of amides are known. The solid complexes of U(VI) with DHDA and CMPO were synthesized and characterized by elemental analysis and IR spectra. Two molecules of DHDA and only one molecule of CMPO are bound with U(VI). The bidentate nature of CMPO in its solid species has been confirmed. (orig.)

  13. Cyanuric acid hydrolase from Azorhizobium caulinodans ORS 571: crystal structure and insights into a new class of Ser-Lys dyad proteins.

    Seunghee Cho

    Full Text Available Cyanuric acid hydrolase (CAH catalyzes the hydrolytic ring-opening of cyanuric acid (2,4,6-trihydroxy-1,3,5-triazine, an intermediate in s-triazine bacterial degradation and a by-product from disinfection with trichloroisocyanuric acid. In the present study, an X-ray crystal structure of the CAH-barbituric acid inhibitor complex from Azorhizobium caulinodans ORS 571 has been determined at 2.7 Å resolution. The CAH protein fold consists of three structurally homologous domains forming a β-barrel-like structure with external α-helices that result in a three-fold symmetry, a dominant feature of the structure and active site that mirrors the three-fold symmetrical shape of the substrate cyanuric acid. The active site structure of CAH is similar to that of the recently determined AtzD with three pairs of active site Ser-Lys dyads. In order to determine the role of each Ser-Lys dyad in catalysis, a mutational study using a highly sensitive, enzyme-coupled assay was conducted. The 10⁹-fold loss of activity by the S226A mutant was at least ten times lower than that of the S79A and S333A mutants. In addition, bioinformatics analysis revealed the Ser226/Lys156 dyad as the only absolutely conserved dyad in the CAH/barbiturase family. These data suggest that Lys156 activates the Ser226 nucleophile which can then attack the substrate carbonyl. Our combination of structural, mutational, and bioinformatics analyses differentiates this study and provides experimental data for mechanistic insights into this unique protein family.

  14. Synthesis and characterization of heat-resistant and soluble poly(amide-imide)s from unsymmetrical dicarboxylic acid containing 2-(triphenyl phosphoranylidene) moiety and various aromatic diamines

    Seema Agrawal; Anudeep Kumar Narula

    2015-04-01

    An unsymmetrical and non-coplaner heterocyclic phosphorus containing dicarboxylic acid monomer, (DCA-3) is successfully synthesized with high purity. A series of novel aromatic poly(amide-imide)s having ether or/sulphur or/fluorine or/phosphorus containing phenyl moieties in their backbone are then prepared via a direct phosphorylation polycondensation of synthesized dicarboxylic acid with various aromatic diamines. Chemical structures of DCA-3 as well as resulting polymers are confirmed by FT-IR, NMR spectroscopic techniques and elemental analysis. These polymers are readily soluble in a variety of aprotic polar solvents such as NMP, DMSO, DMAc and DMF, etc. UV spectra showed that all poy(amide-imide)s films exhibit high optical transparency. In addition, the glass transition temperatures (Tg) of these polymers were determined by differential scanning calorimetry and found in the range 271–346°C. Furthermore, thermogravimetric analysis of these polymers showed good thermal stability, 10% weight loss at temperature in excess of 538°C and char yield at 700°C in nitrogen ranging from 68 to 79%. From wide-angle X-ray diffraction experiments, all polymers showed amorphous behaviour.

  15. Effects of soluble epoxide hydrolase inhibitor on the expression of fatty acid synthase in peripheral blood mononuclear cell in patients with acute coronary syndrome

    Zhao Xuan

    2013-01-01

    Full Text Available Abstract Background Researches have shown that soluble epoxide hydrolase inhibitors (sEHi can protect against the development of atherosclerosis. Simultaneously, emerging evidences have implicated the association between fatty acid synthase (FAS and acute coronary syndrome (ACS. We tested the hypothesis that sEHi could reduce the occurrence of ACS by regulating FAS. Methods Hospitalized ACS patients were selected as the ACS group (n = 65 while healthy normal subjects as the control group (n = 65. The blood levels of lipoproteins, fasting glucose, myocardial enzyme and high-sensitivity C-reactive protein (hs-CRP were measured within 24 hours after admission. The peripheral blood mononuclear cells (PBMCs were isolated and cultured. Trans-4-[4-(3-Adamantan-1-ylureidocyclohexyloxy] benzoic acid (t-AUCB, a kind of sEHi, was then added to cells in various concentrations (0, 10, 50, 100 μmol/L. The expression of FAS, interleukin-6 (IL-6 mRNA and protein was detected by real-time PCR or Western blot, respectively. Results (1 Compared with the control group, the serum concentration of hs-CRP in the ACS group was increased (PPPPP Conclusions sEH inhibition regulated FAS and inhibited inflammation in cultured PBMCs from ACS patients, a mechanism that might prevent rupture of atherosclerotic lesions and protect against development of ACS.

  16. Inhibition of soluble epoxide hydrolase by cis-4-[4-(3-adamantan-1-ylureido)cyclohexyl-oxy]benzoic acid exhibits antihypertensive and cardioprotective actions in transgenic rats with angiotensin II-dependent hypertension

    Neckář, Jan; Kopkan, L.; Husková, Z.; Kolář, František; Papoušek, František; Kramer, H. J.; Hwang, S.H.; Hammock, B.D.; Imig, J. D.; Malý, J.; Netuka, I.; Ošťádal, Bohuslav; Červenka, L.

    2012-01-01

    Roč. 122, č. 11 (2012), s. 513-525. ISSN 0143-5221 R&D Projects: GA AV ČR(CZ) IAAX01110901; GA AV ČR(CZ) KAN200520703; GA MŠk(CZ) 1M0510 Institutional research plan: CEZ:AV0Z50110509 Keywords : hypertension * angiotensin II * kidney * epoxyeicosatrienoic acids * soluble epoxide hydrolase inhibitor * myocardial ischemia/reperfusion injury Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.859, year: 2012

  17. Protective effect of squalene on certain lysosomal hydrolases and free amino acids in isoprenaline-induced myocardial infarction in rats

    Farvin, Sabeena; Surendraraj, A.; Anandan, R.

    2010-01-01

    This study was aimed to evaluate the preventive role of squalene on free amino acids and lysosomal alterations in experimentally induced myocardial infarction in rats. The levels of lysosomal enzymes (beta-glucuronidase, beta-galactosidase, beta-glucosidase, acid phosphatase and cathepsin D) in...... plasma and lysosomal fractions, hydroxyproline content and free amino acids in heart tissue were determined. Isoprenaline administration to rats resulted in decreased stability of the membranes which was reflected by significantly (p...

  18. Hierarchical classification of glycoside hydrolases.

    Naumoff, D G

    2011-06-01

    This review deals with structural and functional features of glycoside hydrolases, a widespread group of enzymes present in almost all living organisms. Their catalytic domains are grouped into 120 amino acid sequence-based families in the international classification of the carbohydrate-active enzymes (CAZy database). At a higher hierarchical level some of these families are combined in 14 clans. Enzymes of the same clan have common evolutionary origin of their genes and share the most important functional characteristics such as composition of the active center, anomeric configuration of cleaved glycosidic bonds, and molecular mechanism of the catalyzed reaction (either inverting, or retaining). There are now extensive data in the literature concerning the relationship between glycoside hydrolase families belonging to different clans and/or included in none of them, as well as information on phylogenetic protein relationship within particular families. Summarizing these data allows us to propose a multilevel hierarchical classification of glycoside hydrolases and their homologs. It is shown that almost the whole variety of the enzyme catalytic domains can be brought into six main folds, large groups of proteins having the same three-dimensional structure and the supposed common evolutionary origin. PMID:21639842

  19. Increased leukotriene B(4) production, complement C3 conversion and acid hydrolase enzyme concentrations in different leucocyte sub-populations of dogs with atopic dermatitis.

    Breathnach, R; Donahy, C; Jones, B R; Bloomfield, F J

    2006-01-01

    Various markers of the inflammatory response were measured in peripheral blood mononuclear cells (PBMCs) and polymorphonuclear neutrophils (PMNs) from 31 dogs with atopic dermatitis (AD). The variables assayed included chemiluminescence, acid hydrolase enzyme concentrations, leukotriene B(4) (LTB(4)) production and complement C3 conversion. The results were compared to those derived from a population of clinically healthy dogs. Dogs with AD exhibited a significant increase in median LTB(4) production in PMNs compared to controls (0.94 versus 0.00 ng/10(6) cells; PPBMC fraction - 0.42 versus 0.25 mU/10(6) cells; PPBMC fraction - 0.52 versus 0.27 mU/10(6) cells; P0.05). However, the median time taken to reach maximum chemiluminescence was significantly shorter in the PMN fraction of dogs with AD (7.00 versus 10.00 min; Pdogs had a significant increase in the median percentage conversion of complement C3 to C3b (66.0 versus 57.3%; Pdogs with AD. The role of LTB(4) in the pathogenesis of canine AD and the potential efficacy of leukotriene antagonists in the treatment of this disorder warrant further investigation. PMID:16427587

  20. Involvement of a Natural Fusion of a Cytochrome P450 and a Hydrolase in Mycophenolic Acid Biosynthesis

    Hansen, Bjarne Gram; Mnich, Ewelina; Nielsen, Kristian Fog; Nielsen, Jakob Blæsbjerg; Nielsen, Morten Thrane; Mortensen, Uffe Hasbro; Larsen, Thomas Ostenfeld; Patil, Kiran Raosaheb

    2012-01-01

    Mycophenolic acid (MPA) is a fungal secondary metabolite and the active component in several immunosuppressive pharmaceuticals. The gene cluster coding for the MPA biosynthetic pathway has recently been discovered in Penicillium brevicompactum, demonstrating that the first step is catalyzed by MpaC, a polyketide synthase producing 5-methylorsellinic acid (5-MOA). However, the biochemical role of the enzymes encoded by the remaining genes in the MPA gene cluster is still unknown. Based on bioi...

  1. Hydrogen abstraction reactions by amide electron adducts

    Electron reactions with a number of peptide model compounds (amides and N-acetylamino acids) in aqueous glasses at low temperature have been investigated using ESR spectroscopy. The radicals produced by electron attachment to amides, RC(OD)NDR', are found to act as hydrogen abstracting agents. For example, the propionamide electron adduct is found to abstract from its parent propionamide. Electron adducts of other amides investigated show similar behavior except for acetamide electron adduct which does not abstract from its parent compound, but does abstract from other amides. The tendency toward abstraction for amide electron adducts are compared to electron adducts of several carboxylic acids, ketones, aldehydes and esters. The comparison suggests the hydrogen abstraction tendency of the various deuterated electron adducts (DEAs) to be in the following order: aldehyde DEA > acid DEA = approximately ester DEA > ketone DEA > amide DEA. In basic glasses the hydrogen abstraction ability of the amide electron adducts is maintained until the concentration of base is increased sufficiently to convert the DEA to its anionic form, RC(O-)ND2. In this form the hydrogen abstracting ability of the radical is greatly diminished. Similar results were found for the ester and carboxylic acid DEA's tested. (author)

  2. Human α/β hydrolase domain containing 10 (ABHD10) is responsible enzyme for deglucuronidation of mycophenolic acid acyl-glucuronide in liver.

    Iwamura, Atsushi; Fukami, Tatsuki; Higuchi, Ryota; Nakajima, Miki; Yokoi, Tsuyoshi

    2012-03-16

    Mycophenolic acid (MPA), the active metabolite of the immunosuppressant mycophenolate mofetil (MMF), is primarily metabolized by glucuronidation to a phenolic glucuronide (MPAG) and an acyl glucuronide (AcMPAG). It is known that AcMPAG, which may be an immunotoxic metabolite, is deglucuronidated in human liver. However, it has been reported that recombinant β-glucuronidase does not catalyze this reaction. AcMPAG deglucuronidation activity was detected in both human liver cytosol (HLC) and microsomes (HLM). In this study, the enzyme responsible for AcMPAG deglucuronidation was identified by purification from HLC with column chromatographic purification steps. The purified enzyme was identified as α/β hydrolase domain containing 10 (ABHD10) by amino acid sequence analysis. Recombinant ABHD10 expressed in Sf9 cells efficiently deglucuronidated AcMPAG with a K(m) value of 100.7 ± 10.2 μM, which was similar to those in HLM, HLC, and human liver homogenates (HLH). Immunoblot analysis revealed ABHD10 protein expression in both HLC and HLM. The AcMPAG deglucuronidation by recombinant ABHD10, HLC, and HLH were potently inhibited by AgNO(3), CdCl(2), CuCl(2), PMSF, bis-p-nitrophenylphosphate, and DTNB. The CL(int) value of AcMPAG formation from MPA, which was catalyzed by human UGT2B7, in HLH was increased by 1.8-fold in the presence of PMSF. Thus, human ABHD10 would affect the formation of AcMPAG, the immunotoxic metabolite. PMID:22294686

  3. Synthesis of Caffeic Acid Amides Bearing 2,3,4,5-Tetra-hydrobenzo[b][1,4]dioxocine Moieties and Their Biological Evaluation as Antitumor Agents

    Ji-Wen Yuan

    2014-06-01

    Full Text Available A series of caffeic acid amides D1-D17 bearing 2,3,4,5-tetrahydrobenzo-[b][1,4]dioxocine units has been synthesized and their biological activities evaluated for potential antiproliferative and EGFR inhibitory activity. Of all the compounds studied, compound D9 showed the most potent inhibitory activity (IC50 = 0.79 μM for HepG2 and IC50 = 0.36 μM for EGFR. The structures of compounds were confirmed by 1H-NMR, ESI-MS and elemental analysis. Among all, the structure of compound D9 ((E-N-(4-ethoxyphenyl-3-(2,3,4,5-tetrahydrobenzo[b][1,4]dioxocin-8-ylacrylamide was also determined by single-crystal X-ray diffraction analysis. Compound D9 was found to be a potential antitumor agent according to biological activity, molecular docking, apoptosis assay and inhibition of HepG2.

  4. Synthesis, Antifungal Activity and Structure-Activity Relationships of Novel 3-(Difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic Acid Amides

    Shijie Du

    2015-05-01

    Full Text Available A series of novel 3-(difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid amides were synthesized and their activities were tested against seven phytopathogenic fungi by an in vitro mycelia growth inhibition assay. Most of them displayed moderate to excellent activities. Among them N-(2-(5-bromo-1H-indazol-1-ylphenyl-3-(difluoro-methyl-1-methyl-1H-pyrazole-4-carboxamide (9m exhibited higher antifungal activity against the seven phytopathogenic fungi than boscalid. Topomer CoMFA was employed to develop a three-dimensional quantitative structure-activity relationship model for the compounds. In molecular docking, the carbonyl oxygen atom of 9m could form hydrogen bonds towards the hydroxyl of TYR58 and TRP173 on SDH.

  5. Synthesis of Racemic Bis[2-(6-fluoro-2-chromanyl)-2-hydroxyethyl]-amine Methanesulfonic Acid Salt Using Lithium Aluminum Amide as a Promoter in Regioselective Ring Opening of Epoxide

    Yun Xu YANG; Nai Xing WANG; Ya Lan XING; Wu Wei WANG; Jia ZHAO; Gui Xia WANG; Shi TANG

    2005-01-01

    Lithium aluminium amide [LiAl(NHR)4] 5 obtained by treating the primary amine 4 with LiAlH4 could promote the ring opening of epoxide 2 and led to high regioselective product of racemic bis[2-(6-fluoro-2-chromanyl)-2-hydroxyethyl]amine methanesulfonic acid salt 7.

  6. Hydrolase-catalyzed synthesis of polyamides and polyester amides

    Stavila, Erythrina

    2014-01-01

    De ontwikkeling van enzymatische polymerisaties duurt al tientallen jaren voort. Er zijn verschillende onderzoeken gedaan op het gebied van enzymatische synthese van polyesters, polycarbonaten, polysaccharides, polypeptides en polyamides, en een aantal hebben reeds industriële toepassing gevonden. L

  7. Involvement of a Natural Fusion of a Cytochrome P450 and a Hydrolase in Mycophenolic Acid Biosynthesis

    Hansen, Bjarne Gram; Mnich, Ewelina; Nielsen, Kristian Fog;

    2012-01-01

    Mycophenolic acid (MPA) is a fungal secondary metabolite and the active component in several immunosuppressive pharmaceuticals. The gene cluster coding for the MPA biosynthetic pathway has recently been discovered in Penicillium brevicompactum, demonstrating that the first step is catalyzed by Mp....... Overall, the chimeric enzyme MpaDE provides insight into the genetic organization of the MPA biosynthesis pathway.......DNA prepared from the extracted RNA. Heterologous coexpression of mpaC and the fusion gene mpaDE in the MPA-nonproducer Aspergillus nidulans resulted in the production of 5,7-dihydroxy-4-methylphthalide (DHMP), the second intermediate in MPA biosynthesis. Analysis of the strain coexpressing mpaC and the mpa...

  8. Valpromide inhibits human epoxide hydrolase.

    Pacifici, G. M.; Franchi, M; Bencini, C; Rane, A

    1986-01-01

    The effect of antipileptic drug valpromide (VPM) on the activity of epoxide hydrolase was studied in human adult and foetal liver, kidneys, lungs, intestine and in placenta. The activity of the epoxide hydrolase was measured with both styrene oxide and benzo(a)pyrene-4,5-oxide as substrates. VPM inhibited the epoxide hydrolase obtained from all organs studied. The degree of inhibition was independent of the substrate used. A lowering of the epoxide hydrolase activity by 50% was observed when ...

  9. Effect of propane-2-sulfonic acid octadec-9-enyl-amide on the expression of adhesion molecules in human umbilical vein endothelial cells.

    Chen, Cai-Xia; Yang, Li-Chao; Xu, Xu-Dong; Wei, Xiao; Gai, Ya-Ting; Peng, Lu; Guo, Han; Hao-Zhou; Wang, Yi-Qing; Jin, Xin

    2015-06-01

    Oleoylethanolamide (OEA), an endogenous agonist of PPARα, has been reported to have anti-atherosclerotic properties. However, OEA can be enzymatically hydrolyzed to oleic acid and ethanolamine and, thus, is not expected to be orally active. In the present study, we designed and synthesized an OEA analog, propane-2-sulfonic acid octadec-9-enyl-amide (N15), which is resistant to enzymatic hydrolysis. The purpose of this study was to investigate the effects of N15 on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). The results showed that N15 inhibited TNFα-induced production of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 and the adhesion of monocytes to TNFα-induced HUVECs. Furthermore, the protective effect of N15 on inflammation is dependent upon a PPAR-α/γ-mediated mechanism. In conclusion, N15 protects against TNFα-induced vascular endothelial inflammation. This anti-inflammatory effect of N15 is dependent on PPAR-α/γ dual targets. PMID:25797284

  10. Hydrolases of the ILR1-like family of Arabidopsis thaliana modulate auxin response by regulating auxin homeostasis in the endoplasmic reticulum.

    Sanchez Carranza, Ana Paula; Singh, Aparajita; Steinberger, Karoline; Panigrahi, Kishore; Palme, Klaus; Dovzhenko, Alexander; Dal Bosco, Cristina

    2016-01-01

    Amide-linked conjugates of indole-3-acetic acid (IAA) have been identified in most plant species. They function in storage, inactivation or inhibition of the growth regulator auxin. We investigated how the major known endogenous amide-linked IAA conjugates with auxin-like activity act in auxin signaling and what role ILR1-like proteins play in this process in Arabidopsis. We used a genetically encoded auxin sensor to show that IAA-Leu, IAA-Ala and IAA-Phe act through the TIR1-dependent signaling pathway. Furthermore, by using the sensor as a free IAA reporter, we followed conjugate hydrolysis mediated by ILR1, ILL2 and IAR3 in plant cells and correlated the activity of the hydrolases with a modulation of auxin response. The conjugate preferences that we observed are in agreement with available in vitro data for ILR1. Moreover, we identified IAA-Leu as an additional substrate for IAR3 and showed that ILL2 has a more moderate kinetic performance than observed in vitro. Finally, we proved that IAR3, ILL2 and ILR1 reside in the endoplasmic reticulum, indicating that in this compartment the hydrolases regulate the rates of amido-IAA hydrolysis which results in activation of auxin signaling. PMID:27063913

  11. A 2:1 co-crystal of p-nitro-benzoic acid and N,N'-bis-(pyridin-3-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.

    Syed, Sabrina; Halim, Siti Nadiah Abdul; Jotani, Mukesh M; Tiekink, Edward R T

    2016-01-01

    The title 2:1 co-crystal, 2C7H5NO4·C14H14N4O2, in which the complete di-amide mol-ecule is generated by crystallographic inversion symmetry, features a three-mol-ecule aggregate sustained by hydroxyl-O-H⋯N(pyrid-yl) hydrogen bonds. The p-nitro-benzoic acid mol-ecule is non-planar, exhibiting twists of both the carb-oxy-lic acid and nitro groups, which form dihedral angles of 10.16 (9) and 4.24 (4)°, respectively, with the benzene ring. The di-amide mol-ecule has a conformation approximating to a Z shape, with the pyridyl rings lying to either side of the central, almost planar di-amide residue (r.m.s. deviation of the eight atoms being 0.025 Å), and forming dihedral angles of 77.22 (6)° with it. In the crystal, three-mol-ecule aggregates are linked into a linear supra-molecular ladder sustained by amide-N-H⋯O(nitro) hydrogen bonds and orientated along [10-4]. The ladders are connected into a double layer via pyridyl- and benzene-C-H⋯O(amide) inter-actions, which, in turn, are connected into a three-dimensional architecture via π-π stacking inter-actions between pyridyl and benzene rings [inter-centroid distance = 3.6947 (8) Å]. An evaluation of the Hirshfeld surfaces confirm the importance of inter-molecular inter-actions involving oxygen atoms as well as the π-π inter-actions. PMID:26870591

  12. [11C]Carbon Monoxide in Palladium- / Selenium-Promoted Carbonylation Reactions : Synthesis of 11C-Imides, Hydrazides, Amides, Carboxylic Acids, Carboxylic Esters, Carbothioates, Ketones and Carbamoyl Compounds

    Karimi, Farhad

    2002-01-01

    [11C]Carbon monoxide in low concentrations has been used in palladium- or seleniummediated carbonylation reactions such as the synthesis of 11C-imides, hydrazides, amides, carboxylic acids, esters, carbothioates, ketones and carbamoyl compounds. In these reactions aryl iodides have been used in most cases. However, less reactive aryl triflate, chloride and bromides were activated using tetrabutylammonium iodide. The reactivities of nucleophiles may have influence on the radiochemical yield of...

  13. On complex compounds of molybdenum(5) with nicotinic amide, isonicotinic acid hydrazide and some of its derivatives

    Oxychloride complexes of molybdenum (5) with polyfunctional ligands (L), namely with nicotinamide (NA), isonicotinic acid hydrazide (INH) and its derivatives (ftivazide, saluzide and larusan) have been synthesized and investigated. In ethanol all the ligands independently of their molar ratio form with MoCl5 a non-electrolite compound MoOCl3xL2. Infrared spectra of the complexes suggest that in Mo(5) complexeS with NA and INH the central atom is bound through the pyridine nitrogen, whereas in the complexes with INH derivatives it is bound throught the carbonyl group oxygen

  14. Synthesis of structurally defined scaffolds for bivalent ligand display based on glucuronic acid anilides. The degree of tertiary amide isomerism and folding depends on the configuration of a glycosyl azide.

    Tosin, Manuela; Murphy, Paul V

    2005-05-13

    [structures: see text] Syntheses and structural analyses of bivalent carbohydrates based on anilides of glucuronic acid are described. Secondary anilides predominantly adopted the Z-anti structure; there is also evidence for population of the Z-syn isomer. Bivalent tertiary anilides displayed two signal sets in their NMR spectra, consistent with the presence of (i) a major isomer where both amides have E configurations (EE) and (ii) a minor isomer where one amide is E and the other Z (EZ). Qualitative NOE/ROE spectroscopic studies in solution support the proposal that the anti conformation is preferred for E amides. The crystal structure of one bivalent tertiary anilide showed E-anti and E-syn structural isomers; intramolecular carbohydrate-carbohydrate stacking was observed and mediated by carbonyl-pyranose, azide-azide, and pyranose-aromatic interactions. The EE to EZ isomer ratio, or the degree of folding, for tertiary amides, was greatest for a bivalent compound containing two alpha-glycosyl azide groups; this was enhanced in water, suggesting that hydrophobic interactions are partially but not wholly responsible. Computational methods predicted azide-aromatic (N...H-C interaction) and azide-azide interactions for folded isomers. The close contact of the azide and aromatic protons (N...H-C interaction) was observed upon examination of the close packing in the crystal structure of a related monomer. It is proposed that the alpha-azide group is more optimally aligned, compared to the beta-azide, to facilitate interaction and minimize the surface area of the hydrophobic groups exposed to water, and this leads to the increased folding. The alkylation of bivalent secondary anilides induces a switch from Z to E amide that alters the scaffold orientation. The synthesis of a bivalent mannoside, based on a secondary anilide scaffold, for investigation of mannose-binding receptor cross-linking and lattice formation is described. PMID:15876103

  15. A 2:1 co-crystal of 2-methyl-benzoic acid and N,N'-bis-(pyridin-4-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.

    Syed, Sabrina; Jotani, Mukesh M; Halim, Siti Nadiah Abdul; Tiekink, Edward R T

    2016-03-01

    The asymmetric unit of the title 2:1 co-crystal, 2C8H8O2·C14H14N4O2, comprises an acid mol-ecule in a general position and half a di-amide mol-ecule, the latter being located about a centre of inversion. In the acid, the carb-oxy-lic acid group is twisted out of the plane of the benzene ring to which it is attached [dihedral angle = 28.51 (8)°] and the carbonyl O atom and methyl group lie approximately to the same side of the mol-ecule [hy-droxy-O-C-C-C(H) torsion angle = -27.92 (17)°]. In the di-amide, the central C4N2O2 core is almost planar (r.m.s. deviation = 0.031 Å), and the pyridyl rings are perpendicular, lying to either side of the central plane [central residue/pyridyl dihedral angle = 88.60 (5)°]. In the mol-ecular packing, three-mol-ecule aggregates are formed via hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds. These are connected into a supra-molecular layer parallel to (12[Formula: see text]) via amide-N-H⋯O(carbon-yl) hydrogen bonds, as well as methyl-ene-C-H⋯O(amide) inter-actions. Significant π-π inter-actions occur between benzene/benzene, pyrid-yl/benzene and pyrid-yl/pyridyl rings within and between layers to consolidate the three-dimensional packing. PMID:27006815

  16. Therapeutic effect of the endogenous fatty acid amide, palmitoylethanolamide, in rat acute inflammation: inhibition of nitric oxide and cyclo-oxygenase systems

    Costa, Barbara; Conti, Silvia; Giagnoni, Gabriella; Colleoni, Mariapia

    2002-01-01

    The anti-inflammatory activity of the endogenous fatty acid amide palmitoylethanolamide and its relationship to cyclo-oxygenase (COX) activity, nitric oxide (NO) and oxygen free radical production were investigated in the rat model of carrageenan-induced acute paw inflammation and compared with the nonsteroidal anti-inflammatory drug (NSAID) indomethacin. Palmitoylethanolamide (1, 3, 5, 10 mg kg−1; p.o.) and indomethacin (5 mg kg−1; p.o.) were administered daily after the onset of inflammation for three days and the paw oedema was measured daily; 24 h after the last dose (fourth day) the rats were killed and the COX activity and the content of nitrite/nitrate (NO2−/NO3−), malondialdehyde (MDA), endothelial and inducible nitric oxide synthase (eNOS and iNOS) were evaluated in the paw tissues. Palmitoylethanolamide had a curative effect on inflammation, inhibiting the carrageenan-induced oedema in a dose- and time-dependent manner. This effect was not reversed by the selective CB2 receptor antagonist (N-[(1S)-endo-1,3,3-trimethylbicyclo[2.2.1]heptan-2yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)pyrazole-3 carboxamide) (SR144528), 3 mg kg−1 p.o. On the fourth day after carrageenan injection, COX activity and the level of NO2−/NO3−, eNOS and MDA were increased in the inflamed paw, but iNOS was not present. Palmitoylethanolamide (10 mg kg−1) and indomethacin markedly reduced these increases. Our findings show, for the first time, that palmitoylethanolamide has a curative effect in a model of acute inflammation. The inhibition of COX activity and of NO and free radical production at the site of inflammation might account for this activity. PMID:12359622

  17. Variation of protein backbone amide resonance by electrostatic field

    Sharley, John N

    2015-01-01

    Amide resonance is found to be sensitive to electrostatic field with component parallel or antiparallel the amide C-N bond. This effect is linear and without threshold in the biologically plausible electrostatic field range -0.005 to 0.005 au. Variation of amide resonance varies Resonance Assisted Hydrogen Bonding such as occurs in the hydrogen bonded chains of backbone amides of protein secondary structures such as beta sheet and non-polyproline helix such as alpha helix, varying the stability of the secondary structure. The electrostatic properties including permittivity of amino acid residue sidegroups influence the electrostatic field component parallel or antiparallel the C-N bond of each amide. The significance of this factor relative to other factors in protein folding depends on the magnitude of electrostatic field component parallel or antiparallel the C-N bond of each amide, and preliminary protein-scale calculations of the magnitude of these components suggest this factor warrants investigation in ...

  18. Biodegradable poly(ester amide)s – A remarkable opportunity for the biomedical area: Review on the synthesis, characterization and

    Fonseca, Ana C.; Gil, Maria H.; Simões, Pedro N.

    2014-01-01

    Poly(ester amide)s have emerged in the last years as an important family of biodegradable synthetic polymers. These polymers present both ester and amide linkages in their structure and they gather in the same entity the good degradability of polyesters with the good thermo-mechanical properties of polyamides. Particularly, poly(ester amide)s containing α-amino acids have risen as important materials in the biomedical field. The presence of the α-amino acid contributes to better cell–polymer ...

  19. Conformation-Specific IR and UV Spectroscopy of the Amino Acid Glutamine: Amide-Stacking and Hydrogen Bonding in AN Important Residue in Neurodegenerative Diseases

    Walsh, Patrick S.; Dean, Jacob C.; Zwier, Timothy S.

    2014-06-01

    Glutamine plays an important role in several neurodegenerative diseases including Huntington's disease (HD) and Alzheimer's disease (AD). An intriguing aspect of the structure of glutamine is its incorporation of an amide group in its side chain, thereby opening up the possibility of forming amide-amide H-bonds between the peptide backbone and side chain. In this study the conformational preferences of two capped gluatamines Z(carboxybenzyl)-Glutamine-X (X=OH, NHMe) are studied under jet-cooled conditions in the gas phase in order to unlock the intrinsic structural motifs that are favored by this flexible sidechain. Conformational assignments are made by comparing the hydride stretch ( 3100-3700 cm-1) and amide I and II ( 1400-1800 cm-1) resonant ion-dip infrared spectra with predictions from harmonic frequency calculations. Assigned structures will be compared to previously published results on both natural and unnatural residues. Particular emphasis will be placed on the comparison between glutamine and unconstrained γ-peptides due to the similar three-carbon spacing between backbone and side chain in glutamine to the backbone spacing in γ-peptides. The ability of the glutamine side-chain to form amide stacked conformations will be a main focus, along with the prevalence of extended backbone type structures. W. H. James, III, C W. Müller, E. G. Buchanan, M. G. D. Nix, L. Guo, L. Roskop, M. S. Gordon, L. V. Slipchenko, S. H. Gellman, and T. S. Zwier, J. Am. Chem. Soc., 2009, 131(40), 14243-14245.

  20. Backbone amide linker strategy

    Shelton, Anne Pernille Tofteng; Jensen, Knud Jørgen

    2013-01-01

    In the backbone amide linker (BAL) strategy, the peptide is anchored not at the C-terminus but through a backbone amide, which leaves the C-terminal available for various modifications. This is thus a very general strategy for the introduction of C-terminal modifications. The BAL strategy was...... assemble the final peptide. One useful application of this strategy is in the synthesis of C-terminal peptide aldehydes. The C-terminal aldehyde is masked as an acetal during synthesis and then conveniently demasked in the final cleavage step to generate the free aldehyde. Another application is in the...

  1. Microwave-assisted synthesis and characterization of camphoric acid chitosan amide%樟脑酸酰化壳聚糖的微波合成及性能表征

    刘振明; 杨艳忠; 李静宇; 谢磊; 杨盛春

    2012-01-01

    以壳聚糖和樟脑酸为原料,在微波辐射下合成了一种新型壳聚糖衍生物——樟脑酸酰化壳聚糖,通过红外(FT-IR)、核磁(1H-NMR)、X-射线衍射(XRD)和热失重(TG)等测试手段对产物结构和性能进行了表征.结果表明樟脑酸通过酰胺键与壳聚糖结合,X-射线结果表明樟脑酸酰化壳聚糖的晶体结构发生了很大的改变,TG分析表明其热稳定性好于壳聚糖.%A new type chitosan derivative,camphoric acid chitosan amide, was synthesized by using of chitosan and camphoric acid as raw materials under microwave irradiation. The chemical structures and properties of the target product were investigated by fourier transform infrared (FT-IR), proton nuclear magnetic resonance spectra CH-NMR), thermogravimetric analyses (TG),and X-ray diffraction (XRD)measurements. The results showed that the camphoric acid is bonded with chitosan by amide-bond. The XRD pattern of product is signicantly different from the crystalline structure of chitosan. TG result demonstrated that thermal stability of the product is better than that of chitosan.

  2. A New Derivative of Valproic Acid Amide Possesses a Broad-spectrum Antiseizure Profile and Unique Activity Against Status Epilepticus and Organophosphate Neuronal Damage

    White, H. Steve; Alex, Anitha B.; Pollock, Amanda; Hen, Naama; Shekh-Ahmad, Tawfeeq; Wilcox, Karen S.; McDonough, John H.; Stables, James P.; Kaufmann, Dan; Yagen, Boris; Bialer, Meir

    2011-01-01

    Summary Purpose sec-Butyl-propylacetamide (SPD) is a one-carbon homologue of valnoctamide (VCD), a CNS-active amide derivative of valproic acid (VPA) currently in phase II clinical trials. The current study evaluated the anticonvulsant activity of SPD in a battery of rodent seizure and epilepsy models and assessed its efficacy in rat and guinea pig models of status epilepticus (SE) and neuroprotection in an organotypic hippocampal slice model of excitotoxic cell death. Methods SPD’s anticonvulsant activity was evaluated in several rodent seizure and epilepsy models including: maximal electroshock (MES), 6Hz psychomotor, subcutaneous (s.c.) metrazol-, s.c., picrotoxin, s.c. bicuculline, audiogenic and corneal and hippocampal kindled seizures following intraperitoneal administration. Results obtained with SPD are discussed in relationship to those obtained with VPA and VCD. SPD was also evaluated for its ability to block benzodiazepine-resistant SE induced by pilocarpine (rats) and soman (rats and guinea pigs) following intraperitoneal administration. SPD was tested for its ability to block excitotoxic cell death induced by the glutamate agonists N-methyl-D-Aspartate (NMDA) and kainic acid (KA) using organotypic hippocampal slices and SE-induced hippocampal cell death using FluoroJade B staining. The cognitive function of SPD-treated rats that were protected against pilocarpine-induced convulsive SE was examined 10-14 days post SE using the Morris water maze (MWM). The relationship between the pharmacokinetic profile of SPD and its efficacy against soman-induced SE was evaluated in two parallel studies following SPD (60 mg/kg, i.p.) administration in the soman SE rat model. Key Findings SPD was highly effective and displayed a wide protective index (PI=TD50/ED50) in the standardized seizure and epilepsy models employed. SPD’s wide PI values demonstrate that it is effective at doses well below those that produce behavioral impairment. Unlike VCD, SPD also

  3. Tertiary fatty amides as diesel fuel substitutes

    Serdari, Aikaterini; Lois, Euripides; Stournas, Stamoulis [National Technical Univ. of Athens, Dept. of Chemical Engineering, Athens (Greece)

    2000-07-01

    This paper presents experimental results regarding the impact of adding different tertiary amides of fatty acids to mineral diesel fuel; an assessment of the behaviour of these compounds as possible diesel fuel extenders is also included. Measurements of cetane number, cold flow properties (cloud point, pour point and CFPP), density, kinematic viscosity, flash point and distillation temperatures are reported, while initial experiments concerning the effects on particulate emissions are also described. Most of the examined tertiary fatty amides esters have very good performance and they can be easily prepared from fatty acids (biomass). Such compounds or their blends could be used as mineral diesel fuel or even fatty acid methylesters (FAME, biodiesel) substitutes or extenders. (Author)

  4. Peptidyl-urea based inhibitors of soluble epoxide hydrolases

    We prepared a series of amino acid derived cyclohexyl and adamantyl ureas and tested them as inhibitors of the human soluble epoxide hydrolase, and obtained very potent compounds (K(I)=15nM) that are >10-fold more soluble than previously described sEH inhibitors. While our lead compound 2 showed low...

  5. Limonene-1,2-Epoxide Hydrolase from Rhodococcus erythropolis DCL14 Belongs to a Novel Class of Epoxide Hydrolases

    van der Werf, Mariët J.; Overkamp, Karin M; de Bont, Jan A. M.

    1998-01-01

    An epoxide hydrolase from Rhodococcus erythropolis DCL14 catalyzes the hydrolysis of limonene-1,2-epoxide to limonene-1,2-diol. The enzyme is induced when R. erythropolis is grown on monoterpenes, reflecting its role in the limonene degradation pathway of this microorganism. Limonene-1,2-epoxide hydrolase was purified to homogeneity. It is a monomeric cytoplasmic enzyme of 17 kDa, and its N-terminal amino acid sequence was determined. No cofactor was required for activity of this colorless en...

  6. Transcription of the Human Microsomal Epoxide Hydrolase Gene (EPHX1 Is Regulated by PARP-1 and Histone H1.2. Association with Sodium-Dependent Bile Acid Transport.

    Hui Peng

    Full Text Available Microsomal epoxide hydrolase (mEH is a bifunctional protein that plays a central role in the metabolism of numerous xenobiotics as well as mediating the sodium-dependent transport of bile acids into hepatocytes. These compounds are involved in cholesterol homeostasis, lipid digestion, excretion of xenobiotics and the regulation of several nuclear receptors and signaling transduction pathways. Previous studies have demonstrated the critical role of GATA-4, a C/EBPα-NF/Y complex and an HNF-4α/CAR/RXR/PSF complex in the transcriptional regulation of the mEH gene (EPHX1. Studies also identified heterozygous mutations in human EPHX1 that resulted in a 95% decrease in mEH expression levels which was associated with a decrease in bile acid transport and severe hypercholanemia. In the present investigation we demonstrate that EPHX1 transcription is significantly inhibited by two heterozygous mutations observed in the Old Order Amish population that present numerous hypercholanemic subjects in the absence of liver damage suggesting a defect in bile acid transport into the hepatocyte. The identity of the regulatory proteins binding to these sites, established using biotinylated oligonucleotides in conjunction with mass spectrometry was shown to be poly(ADP-ribosepolymerase-1 (PARP-1 bound to the EPHX1 proximal promoter and a linker histone complex, H1.2/Aly, bound to a regulatory intron 1 site. These sites exhibited 71% homology and may represent potential nucleosome positioning domains. The high frequency of the H1.2 site polymorphism in the Amish population results in a potential genetic predisposition to hypercholanemia and in conjunction with our previous studies, further supports the critical role of mEH in mediating bile acid transport into hepatocytes.

  7. Role of soluble epoxide hydrolase in the sex-specific vascular response to cerebral ischemia

    Zhang, Wenri; Iliff, Jeffrey J.; Campbell, Caitlyn J; Wang, Ruikang K.; Hurn, Patricia D.; Alkayed, Nabil J.

    2009-01-01

    Soluble epoxide hydrolase (sEH), a key enzyme in the metabolism of vasodilator eicosanoids called epoxyeicosatrienoic acids (EETs), is sexually dimorphic and suppressed by estrogen. We determined if the sex difference in blood flow during focal cerebral ischemia is linked to sEH. Soluble epoxide hydrolase expression in brain, hydrolase activity in cerebral vessels, and plasma 14,15-dihydroxyeicosatrienoic acid (14,15-DHET) were determined in male and female wild-type (WT) and sEH knockout (sE...

  8. Hydrogen Bonds between Acidic Protons from Alkynes (C–H···O and Amides (N–H···O and Carbonyl Oxygen Atoms as Acceptor Partners

    Pierre Baillargeon

    2014-01-01

    Full Text Available Crystals of tert-butyl (2S-2-(prop-2-yn-1-ylcarbamoylpyrrolidine-1-carboxylate (Boc-L-Pro-NHCH2CCH have been obtained. The title compound crystallizes easily as sharp needles in orthorhombic system, space group P 21 21 21 with a = 9.2890(2, b = 9.7292(2, c = 15.7918(4 Å, V = 1427.18(6 Å3, and Z = 4. The main feature of the structure is the orientation of the carbamate and amide. Their dipoles add up and the molecule displays an electric dipole moment of 5.61 D from B3LYP/6-31G(d calculations. The antiparallel H bonding of amides and the alignment of dipoles induce columnar stacking (the dipole moment along the columnar a axis is 4.46 D for each molecule. The other components across the other axes are, therefore weaker, (3.17 D and 1.23 D along the b and c axes, resp.. The resulting anisotropic columns pack side by side, in an antiparallel fashion mostly by (alkyne CH···O=C (carbamate interactions.

  9. Polyglycine hydrolases secreted by pathogenic fungi

    Pathogens are known to produce proteases that target host defense proteins. Here we describe polyglycine hydrolases, fungal proteases that selectively cleave glycine-glycine peptide bonds within the polyglycine interdomain linker of targeted plant defense chitinases. Polyglycine hydrolases were puri...

  10. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH), endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide) were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD) and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR), adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity. PMID:26561012

  11. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enz...

  12. Fatty Acid Amide Hydrolase (FAAH), Acetylcholinesterase (AChE), and Butyrylcholinesterase (BuChE): Networked Targets for the Development of Carbamates as Potential Anti-Alzheimer's Disease Agents.

    Montanari, Serena; Scalvini, Laura; Bartolini, Manuela; Belluti, Federica; Gobbi, Silvia; Andrisano, Vincenza; Ligresti, Alessia; Di Marzo, Vincenzo; Rivara, Silvia; Mor, Marco; Bisi, Alessandra; Rampa, Angela

    2016-07-14

    The modulation of the endocannabinoid system is emerging as a viable avenue for the treatment of neurodegeneration, being involved in neuroprotective and anti-inflammatory processes. In particular, indirectly enhancing endocannabinoid signaling to therapeutic levels through FAAH inhibition might be beneficial for neurodegenerative disorders such as Alzheimer's disease, effectively preventing or slowing the progression of the disease. Hence, in the search for a more effective treatment for Alzheimer's disease, in this paper, the multitarget-directed ligand paradigm was applied to the design of carbamates able to simultaneously target the recently proposed endocannabinoid system and the classic cholinesterase system, and achieve effective dual FAAH/cholinesterase inhibitors. Among the two series of synthesized compounds, while some derivatives proved to be extremely potent on a single target, compounds 9 and 19 were identified as effective dual FAAH/ChE inhibitors, with well-balanced nanomolar activities. Thus, 9 and 19 might be considered as new promising candidates for Alzheimer's disease treatment. PMID:27309570

  13. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Cyro José de Moraes Martins

    Full Text Available The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH, endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR, adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity.

  14. Advances in the discovery of N-acylethanolamine acid amidase inhibitors.

    Bandiera, Tiziano; Ponzano, Stefano; Piomelli, Daniele

    2014-08-01

    N-Acylethanolamine acid amidase (NAAA) is a cysteine amidase that hydrolyzes saturated or monounsaturated fatty acid ethanolamides, such as palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). PEA has been shown to exert analgesic and anti-inflammatory effects by engaging peroxisome proliferator-activated receptor-α. Like other fatty acid ethanolamides, PEA is not stored in cells, but produced on demand from cell membrane precursors, and its actions are terminated by intracellular hydrolysis by either fatty acid amide hydrolase or NAAA. Endogenous levels of PEA and OEA have been shown to decrease during inflammation. Modulation of the tissue levels of PEA by inhibition of enzymes responsible for the breakdown of this lipid mediator may represent therefore a new therapeutic strategy for the treatment of pain and inflammation. While a large number of inhibitors of fatty acid amide hydrolase have been discovered, few compounds have been reported to inhibit NAAA activity. Here, we describe the most representative NAAA inhibitors and briefly highlight their pharmacological profile. A recent study has shown that a NAAA inhibitor attenuated heat hyperalgesia and mechanical allodynia caused by local inflammation or nerve damage in animal models of pain and inflammation. This finding encourages further exploration of the pharmacology of NAAA inhibitors. PMID:24798679

  15. Cloning of a Novel Arylamidase Gene from Paracoccus sp. Strain FLN-7 That Hydrolyzes Amide Pesticides

    Zhang, Jun; Yin, Jin-Gang; Hang, Bao-Jian; Cai, Shu; He, Jian; Zhou, Shun-Gui; Li, Shun-Peng

    2012-01-01

    The bacterial isolate Paracoccus sp. strain FLN-7 hydrolyzes amide pesticides such as diflubenzuron, propanil, chlorpropham, and dimethoate through amide bond cleavage. A gene, ampA, encoding a novel arylamidase that catalyzes the amide bond cleavage in the amide pesticides was cloned from the strain. ampA contains a 1,395-bp open reading frame that encodes a 465-amino-acid protein. AmpA was expressed in Escherichia coli BL21 and homogenously purified using Ni-nitrilotriacetic acid affinity c...

  16. Primary structure and catalytic mechanism of the epoxide hydrolase from Agrobacterium radiobacter AD1

    Rink, R; Fennema, M.; Smids, M; Dehmel, U; Janssen, DB

    1997-01-01

    The epoxide hydrolase gene from Agrobacterium radiobacter AD1, a bacterium that is able to grow on epichlorohydrin as the sole carbon source, was cloned by means of the polymerase chain reaction with two degenerate primers based on the N-terminal and C-terminal sequences of the enzyme, The epoxide hydrolase gene coded for a protein of 294 amino acids with a molecular mass of 34 kDa, An identical epoxide hydrolase gene was cloned from chromosomal DNA of the closely related strain A, radiobacte...

  17. [Amides of creatine: perspectives of neuroprotection].

    Vlasov, T D; Chefu, S G; Baĭsa, A E; Leko, M V; Burov, S V; Veselkina, O S

    2011-07-01

    We evaluated the efficacy of derivatives of creatine and amino acids (CrAA) for decreasing cerebral injury in rats with transient middle cerebral artery occlusion (MCAO). Neuroprotective effects of amides of creatine and glycine (CrGlyOEt), phenylalanine (CrPheNH2), thyrosine (CrTyrNH2), and GABA (CrGABAOEt) were investigated. Brain injury was evaluated on day 2 after transient MCAO using a TTC staining of brain slices. Compared with the MCAO control group, all the CrAms showed decreased cerebral injury (p < 0.05). However CrPheNH2, CrTyrNH2, and CrGABAOEt were toxic after intravenous administration and investigated only after intraperitoneal injection. CrGlyOEt did not show any toxicity at dose of 1 mmol/kg. These data evidenced that creatinyl amides can represent promising candidates for the development of new drugs useful in brain ischemia treatment. PMID:21961295

  18. Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

    Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with [3H] ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major [3H]ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release [3H]ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues

  19. CREST - a large and diverse superfamily of putative transmembrane hydrolases

    Olson Eric N

    2011-07-01

    Full Text Available Abstract Background A number of membrane-spanning proteins possess enzymatic activity and catalyze important reactions involving proteins, lipids or other substrates located within or near lipid bilayers. Alkaline ceramidases are seven-transmembrane proteins that hydrolyze the amide bond in ceramide to form sphingosine. Recently, a group of putative transmembrane receptors called progestin and adipoQ receptors (PAQRs were found to be distantly related to alkaline ceramidases, raising the possibility that they may also function as membrane enzymes. Results Using sensitive similarity search methods, we identified statistically significant sequence similarities among several transmembrane protein families including alkaline ceramidases and PAQRs. They were unified into a large and diverse superfamily of putative membrane-bound hydrolases called CREST (alkaline ceramidase, PAQR receptor, Per1, SID-1 and TMEM8. The CREST superfamily embraces a plethora of cellular functions and biochemical activities, including putative lipid-modifying enzymes such as ceramidases and the Per1 family of putative phospholipases involved in lipid remodeling of GPI-anchored proteins, putative hormone receptors, bacterial hemolysins, the TMEM8 family of putative tumor suppressors, and the SID-1 family of putative double-stranded RNA transporters involved in RNA interference. Extensive similarity searches and clustering analysis also revealed several groups of proteins with unknown function in the CREST superfamily. Members of the CREST superfamily share seven predicted core transmembrane segments with several conserved sequence motifs. Conclusions Universal conservation of a set of histidine and aspartate residues across all groups in the CREST superfamily, coupled with independent discoveries of hydrolase activities in alkaline ceramidases and the Per1 family as well as results from previous mutational studies of Per1, suggests that the majority of CREST members are

  20. Detoxification Strategy of Epoxide Hydrolase

    Arand, Michael; Cronin, Annette; Hengstler, Jan G.; Herrero Plana, Maria Elena; Lohmann, Matthias; Oesch, Franz

    2003-01-01

    The human microsomal epoxide hydrolase, a single enzyme, has to detoxify a broad range of structurally diverse, potentially genotoxic epoxides that are formed in the course of xenobiotic metabolism. The enzyme has developed a unique strategy to combine a broad substrate specificity with a high detoxification efficacy, by immediately trapping the reactive compounds as covalent intermediates and by being expressed at high levels for high trapping capacity. Computer simulation and experimental d...

  1. Tandem dissolution of UO3 in amide-based acidic ionic liquid and in situ electrodeposition of UO2 with regeneration of the ionic liquid: a closed cycle.

    Wanigasekara, Eranda; Freiderich, John W; Sun, Xiao-Guang; Meisner, Roberta A; Luo, Huimin; Delmau, Lætitia H; Dai, Sheng; Moyer, Bruce A

    2016-06-21

    A closed cycle is demonstrated for the tandem dissolution and electroreduction of UO3 to UO2 with regeneration of the acidic ionic liquid. The dissolution is achieved by use of the acidic ionic liquid [DMAH][NTf2] in [EMIM][NTf2] serving as the diluent. A sequential dissolution, electroreduction, and regeneration cycle is presented. PMID:27255672

  2. Possible evidence of amide bond formation between sinapinic acid and lysine-containing bacterial proteins by matrix-assisted laser desorption/ionization (MALDI) at 355 nm

    We previously reported the apparent formation of matrix adducts of 3,5-dimethoxy-4-hydroxy-cinnamic acid (sinapinic acid or SA) via covalent attachment to disulfide bond-containing proteins (HdeA, HdeB and YbgS) from bacterial cell lysates ionized by matrix-assisted laser desorption/ionization (MALD...

  3. Les lipases sont des hydrolases atypiques : principales caractéristiques et applications

    Fickers P.

    2008-01-01

    Full Text Available ipases are atypical hydrolases: principal characteristics and applications. Due to their kinetic and substrate specificities, triacylglycerol acyl-hydrolases or lipases are atypical enzymes. In function of their microenvironment, lipases are able to act as hydrolases in aqueous solution or as biocatalysts in organic synthesis. As hydrolases, they are responsible of the triglycerids catabolism into fatty acids and glycerol. In many organisms, this reaction plays a major role in the fat and lipid metabolism. In addition, lipases are also able to hydrolyse phospholipids and cholesterol esters. In organic solvent, lipases could catalyse reactions such as esterifications, acidolysis or alcoolysis with enantio-, regio- and chimioselectivity. Lipases form a mixed class of enzyme due to their animal, vegetal or microbial origins. All those properties led to the development of many applications in the food and chemical industries but also in the medical and therapeutic field.

  4. The ortho backbone amide linker (o-BAL) is an easily prepared and highly acid-labile handle for solid-phase synthesis

    Boas, Ulrik; Brask, Jesper; Christensen, J.B.;

    2002-01-01

    , followed by purification through steam distillation, Cleavage studies of Leu-enkephalin anchored to either o-BAL or p-BAL handles revealed that both handles were surprisingly acid-labile and released the peptide with dilute TFA (5% and even 1% TFA in CH2Cl2). This useful property allowed the synthesis of...

  5. Ability of Serum Glial Fibrillary Acidic Protein, Ubiquitin C-Terminal Hydrolase-L1, and S100B To Differentiate Normal and Abnormal Head Computed Tomography Findings in Patients with Suspected Mild or Moderate Traumatic Brain Injury.

    Welch, Robert D; Ayaz, Syed I; Lewis, Lawrence M; Unden, Johan; Chen, James Y; Mika, Valerie H; Saville, Ben; Tyndall, Joseph A; Nash, Marshall; Buki, Andras; Barzo, Pal; Hack, Dallas; Tortella, Frank C; Schmid, Kara; Hayes, Ronald L; Vossough, Arastoo; Sweriduk, Stephen T; Bazarian, Jeffrey J

    2016-01-15

    Head computed tomography (CT) imaging is still a commonly obtained diagnostic test for patients with minor head injury despite availability of clinical decision rules to guide imaging use and recommendations to reduce radiation exposure resulting from unnecessary imaging. This prospective multicenter observational study of 251 patients with suspected mild to moderate traumatic brain injury (TBI) evaluated three serum biomarkers' (glial fibrillary acidic protein [GFAP], ubiquitin C-terminal hydrolase-L1 [UCH-L1] and S100B measured within 6 h of injury) ability to differentiate CT negative and CT positive findings. Of the 251 patients, 60.2% were male and 225 (89.6%) had a presenting Glasgow Coma Scale score of 15. A positive head CT (intracranial injury) was found in 36 (14.3%). UCH-L1 was 100% sensitive and 39% specific at a cutoff value >40 pg/mL. To retain 100% sensitivity, GFAP was 0% specific (cutoff value 0 pg/mL) and S100B had a specificity of only 2% (cutoff value 30 pg/mL). All three biomarkers had similar values for areas under the receiver operator characteristic curve: 0.79 (95% confidence interval; 0.70-0.88) for GFAP, 0.80 (0.71-0.89) for UCH-L1, and 0.75 (0.65-0.85) for S100B. Neither GFAP nor UCH-L1 curve values differed significantly from S100B (p = 0.21 and p = 0.77, respectively). In our patient cohort, UCH-L1 outperformed GFAP and S100B when the goal was to reduce CT use without sacrificing sensitivity. UCH-L1 values <40 pg/mL could potentially have aided in eliminating 83 of the 215 negative CT scans. These results require replication in other studies before the test is used in actual clinical practice. PMID:26467555

  6. Design and synthesis of isoniazide mimetic conjugated with DTPA, potential ligand of novel radiopharmaceutical and contrast agent for medical imaging, bis (amide) of diethylenetriaminepentaacetic acid: DTPA-Bis(INH)

    The structure of isonicotinic acid hydrazide (INH) was coupled to diethylenetriaminepentaacetic acid (DTPA) via amide linkage. The overall yield of three steps synthesis starting from DTPA is above 80%. In particular, complexation of DTPA moiety with 99mTc showed excellent results as the metallopharmaceutical for medical imaging. The main objective of the present research was to develop a novel INH derivative based on DTPA, which forms stable complexes with most of the lanthanides and transition metals in the periodic table. A second objective was to introduce a chelating group without compromising the biological activity of the anti-infective drug for the diagnosis of infection using nuclear medicine. The DTPA-Bis(INH) was synthesized in high yield using a simple synthetic procedure and was characterized using mass spectroscopy in ESI positive mode ([M+H+] was found to be 632.2). Moreover, the complex with the DTPA-Bis(INH) is reflected in increased kinetic ability of the stabilized 99mTc complex compared with the unmodified INH. The complex was successfully labelled with the 99mTc radionuclide with more than 95% labelling efficiency. Radiochemical purity was ascertained chromatographically (ITLC and C18 RP chromatography) using different solvent systems. Blood kinetics in rabbits and biodistribution in mice was studied. Blood kinetics showed rapid first pass clearance with a biological half-life, t1/2 (F), of 11 min. The ability of DTPA-Bis(INH) to target the infection site in vivo was assessed in gamma scintigraphic studies of normal rabbit and a rabbit with induced infections. From the present work it can be concluded that the radiolabelled DTPABis( INH) accumulates at the site of infection. (author)

  7. [Effect of anti-arteriosclerosis diet, containing soya protein isolate and omega-3 polyunsaturated fatty acids on the activity of mononuclear and platelet lysosomal hydrolases in patients with hypertension and ischemic heart disease].

    Samsonov, M A; Pogozhaeva, A V; Vasilév, A V; Bogdanova, S N; Pokrovskaia, G R; Varsanovich, E A; Orlova, L A

    1993-01-01

    In response to antiatherosclerosis dietotherapy containing 20 g of ichthyenic oil, coronary and hypertensive subjects showed lowered serum levels of cholesterol, triglycerides and atherogenic index, elevated HDLP cholesterol and corrected immunochemical shifts. SPI-containing diet resulted in changes of CIC IgM levels only. Shifts in the activity of mononuclear and platelet lysosomal hydrolases which occurred in the above patients due to relevant diets reflect higher sensitivity of this parameter in assessment of the dietotherapy effectiveness. PMID:7975402

  8. Endocannabinoid and cannabinoid-like fatty acid amide levels correlate with pain-related symptoms in patients with IBS-D and IBS-C: a pilot study.

    Jakub Fichna

    Full Text Available AIMS: Irritable bowel syndrome (IBS is a functional gastrointestinal (GI disorder, associated with alterations of bowel function, abdominal pain and other symptoms related to the GI tract. Recently the endogenous cannabinoid system (ECS was shown to be involved in the physiological and pathophysiological control of the GI function. The aim of this pilot study was to investigate whether IBS defining symptoms correlate with changes in endocannabinoids or cannabinoid like fatty acid levels in IBS patients. METHODS: AEA, 2-AG, OEA and PEA plasma levels were determined in diarrhoea-predominant (IBS-D and constipation-predominant (IBS-C patients and were compared to healthy subjects, following the establishment of correlations between biolipid contents and disease symptoms. FAAH mRNA levels were evaluated in colonic biopsies from IBS-D and IBS-C patients and matched controls. RESULTS: Patients with IBS-D had higher levels of 2AG and lower levels of OEA and PEA. In contrast, patients with IBS-C had higher levels of OEA. Multivariate analysis found that lower PEA levels are associated with cramping abdominal pain. FAAH mRNA levels were lower in patients with IBS-C. CONCLUSION: IBS subtypes and their symptoms show distinct alterations of endocannabinoid and endocannabinoid-like fatty acid levels. These changes may partially result from reduced FAAH expression. The here reported changes support the notion that the ECS is involved in the pathophysiology of IBS and the development of IBS symptoms.

  9. On DABAL-Me₃ promoted formation of amides

    Dubois, Nathalie; Glynn, Daniel; McInally, Thomas; Rhodes, Barrie; Woodward, Simon; Irvine, Derek; Dodds, Chris

    2013-01-01

    The range and utility of DABAL-Me3 couplings of methyl esters and free carboxylic acids with primary and secondary amines under a variety of conditions (reflux, sealed tube, microwave) has been compared for a significant range of coupling partners of relevance to the preparation of amides of interest in pharmaceutical chemistry. Commercial microwave reactors promote the fastest couplings and allow the use of significantly sterically hindered amines (primary and secondary) and carboxylic acids...

  10. Cellular Inhibition of Checkpoint Kinase 2 (Chk2) and Potentiation of Camptothecins and Radiation by the Novel Chk2 Inhibitor PV1019 [7-Nitro-1H-indole-2-carboxylic acid {4-[1-(guanidinohydrazone)-ethyl]-phenyl}-amide

    Jobson, Andrew G.; Lountos, George T.; Lorenzi, Philip L.; Llamas, Jenny; Connelly, John; Cerna, David; Tropea, Joseph E.; Onda, Akikazu; Zoppoli, Gabriele; Kondapaka, Sudhir; Zhang, Guangtao; Caplen, Natasha J.; Cardellina, II, John H.; Yoo, Stephen S.; Monks, Anne; Self, Christopher; Waugh, David S.; Shoemaker, Robert H.; Pommier, Yves; (NIH)

    2010-04-05

    Chk2 is a checkpoint kinase involved in the ataxia telangiectasia mutated pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported 4,4'-diacetyldiphenylurea-bis(guanylhydrazone) (NSC 109555) as a novel chemotype Chk2 inhibitor. We have now synthesized a derivative of NSC 109555, PV1019 (NSC 744039) [7-nitro-1H-indole-2-carboxylic acid {l_brace}4-[1-(guanidinohydrazone)-ethyl]-phenyl{r_brace}-amide], which is a selective submicromolar inhibitor of Chk2 in vitro. The cocrystal structure of PV1019 bound in the ATP binding pocket of Chk2 confirmed enzymatic/biochemical observations that PV1019 acts as a competitive inhibitor of Chk2 with respect to ATP. PV1019 was found to inhibit Chk2 in cells. It inhibits Chk2 autophosphorylation (which represents the cellular kinase activation of Chk2), Cdc25C phosphorylation, and HDMX degradation in response to DNA damage. PV1019 also protects normal mouse thymocytes against ionizing radiation-induced apoptosis, and it shows synergistic antiproliferative activity with topotecan, camptothecin, and radiation in human tumor cell lines. We also show that PV1019 and Chk2 small interfering RNAs can exert antiproliferative activity themselves in the cancer cells with high Chk2 expression in the NCI-60 screen. These data indicate that PV1019 is a potent and selective inhibitor of Chk2 with chemotherapeutic and radiosensitization potential.

  11. Polymer amide as an early topology.

    Julie E M McGeoch

    Full Text Available Hydrophobic polymer amide (HPA could have been one of the first normal density materials to accrete in space. We present ab initio calculations of the energetics of amino acid polymerization via gas phase collisions. The initial hydrogen-bonded di-peptide is sufficiently stable to proceed in many cases via a transition state into a di-peptide with an associated bound water molecule of condensation. The energetics of polymerization are only favorable when the water remains bound. Further polymerization leads to a hydrophobic surface that is phase-separated from, but hydrogen bonded to, a small bulk water complex. The kinetics of the collision and subsequent polymerization are discussed for the low-density conditions of a molecular cloud. This polymer in the gas phase has the properties to make a topology, viz. hydrophobicity allowing phase separation from bulk water, capability to withstand large temperature ranges, versatility of form and charge separation. Its flexible tetrahedral carbon atoms that alternate with more rigid amide groups allow it to deform and reform in hazardous conditions and its density of hydrogen bonds provides adhesion that would support accretion to it of silicon and metal elements to form a stellar dust material.

  12. Generation of a novel monoclonal antibody that recognizes the alpha (α)-amidated isoform of a valine residue

    Antón Palma, Benito; Leff Gelman, Philippe; Medecigo Ríos, Mayra; Calva Nieves, Juan Carlos; Acevedo Ortuño, Rodolfo; Matus Ortega, Maura Epifanía; Hernández Calderón, Jorge Alberto; Hernández Miramontes, Ricardo; Flores Zamora, Anabel; Salazar Juárez, Alberto

    2015-01-01

    Background Alpha (α)-amidation of peptides is a mechanism required for the conversion of prohormones into functional peptide sequences that display biological activities, receptor recognition and signal transduction on target cells. Alpha (α)-amidation occurs in almost all species and amino acids identified in nature. C-terminal valine amide neuropeptides constitute the smallest group of functional peptide compounds identified in neurosecretory structures in vertebrate and invertebrate specie...

  13. Synthesis of Glycosyl Amides Using Selenocarboxylates as Traceless Reagents for Amide Bond Formation.

    Silva, Luana; Affeldt, Ricardo F; Lüdtke, Diogo S

    2016-07-01

    Carbohydrate-derived amides were successfully prepared in good yields from a broad range of substrates, including furanosyl and pyranosyl derivatives. The methodology successfully relied on the in situ generation of lithium selenocarboxylates from Se/LiEt3BH and acyl chlorides or carboxylic acids and their reaction with sugar azides. A key aspect of the present protocol is that we start from elemental selenium; isolation and handling of all reactive and sensitive selenium-containing intermediates is avoided, therefore providing the selenocarboxylate the status of a traceless reagent. PMID:27275515

  14. Synthesis of novel naphthoquinone aliphatic amides and esters and their anticancer evaluation.

    Kongkathip, Boonsong; Akkarasamiyo, Sunisa; Hasitapan, Komkrit; Sittikul, Pichamon; Boonyalai, Nonlawat; Kongkathip, Ngampong

    2013-02-01

    Fourteen new naphthoquinone aliphatic amides and seventeen naphthoquinone aliphatic esters were synthesized in nine to ten steps from 1-hydroxy-2-naphthoic acid with 9-25% overall yield for the amides, and 16-21% overall yield for the esters. The key step of the amide synthesis is a coupling reaction between amine and various aliphatic acids using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) as a coupling agent while for the ester synthesis, DCC/DMAP or CDI was used as the coupling reagent between aliphatic acids and naphthoquinone alcohol. Both naphthoquinone amides and esters were evaluated for their anticancer activity against KB cells. It was found that naphthoquinone aliphatic amides showed stronger anticancer activity than those of the esters when the chains are longer than 7-carbon atoms. The optimum chain of amides is expected to be 16-carbon atoms. In addition, naphthoquinone aliphatic esters with α-methyl on the ester moiety possessed much stronger anticancer activity than the straight chains. Decatenation assay revealed that naphthoquinone amide with 16-carbon atoms chain at 15 μM and 20 μM can completely inhibit hTopoIIα activity while at 10 μM the enzyme activity was moderately inhibited. Molecular docking result also showed the same trend as the cytotoxicity and decatenation assay. PMID:23313636

  15. The Wood Rot Ascomycete Xylaria polymorpha Produces a Novel GH78 Glycoside Hydrolase That Exhibits α-l-Rhamnosidase and Feruloyl Esterase Activities and Releases Hydroxycinnamic Acids from Lignocelluloses

    Nghi, Do Huu; Bittner, Britta; Kellner, Harald; Jehmlich, Nico; Ullrich, René; Pecyna, Marek J.; Nousiainen, Paula; Sipilä, Jussi; Huong, Le Mai; Hofrichter, Martin; Liers, Christiane

    2012-01-01

    Soft rot (type II) fungi belonging to the family Xylariaceae are known to substantially degrade hardwood by means of their poorly understood lignocellulolytic system, which comprises various hydrolases, including feruloyl esterases and laccase. In the present study, several members of the Xylariaceae were found to exhibit high feruloyl esterase activity during growth on lignocellulosic materials such as wheat straw (up to 1,675 mU g−1) or beech wood (up to 80 mU g−1). Following the ester-clea...

  16. Design and synthesis of isoniazide mimetic conjugated with DTPA, potential ligand of novel radiopharmaceutical and contrast agent for medical imaging, Bis (amide) of diethyelene triaminepentaacetic acid: DTPA-Bis(INH)

    The structure of isonicotinic acid hydrazide was coupled to diethylenetriaminepentaacetic acid (DTPA) via amide linkage. The Overall yield of three steps synthesis starting from DTPA is above 80%. The new ligand binds with infection site through specific interaction with gene iniA, iniB and iniC under pathological conditions. In particular, complexation of DTPA moiety with 99mTc and Gd+III showed excellent results as metallopharmaceutical for medical imaging. Primary object of the present invention is to propose a novel INH derivative based on DTPA, which form stable complexes with most of lanthanides and transition metals in periodic table. Another object of the present invention is to introduce a chelating group without compromising its biological activity for early diagnosis of infection using nuclear medicine and MR techniques. The DTPA-Bis(INH) was synthesized in high yield using simple synthetic procedure. Radiochemical purity was ascertained chromatographically using different solvent system. Blood kinetics in rabbits and biodistribution in mice was studied. The ability of DTPA-Bis(INH) to target infection site in vivo was assessed in gamma scintigraphic studies of normal rabbit and a rabbit with induced tuberculosis. The DTPA-Bis(INH) was characterized by Mass spectroscopy in ESI positive mode, M+H+ was found to be 632.2.The complex was successfully labeled with 99mTc radionuclide with more than 95% labeling efficiency.It was found stable up to 24h. Blood kinetics showed rapid first pass clearance with biological half life t1/2 (F) = 11 min. Imaging of a normal rabbit and a rabbit with induced tuberculosis was carried out. An appreciable activity was visualized in liver and kidneys. In diseased rabbit similar pattern was observed with the accumulation of activity at the tubercular site at 24 h post injection. Biodistribution revealed major accumulation in liver 6.30±0.58%ID/g at 1 h and 6.25±0.11 at 4h and in kidneys 7.65±0.52%ID/g at 1h and 6.70±0

  17. Langmuir films of an amide extracted from Piperaceae and its interaction with phospholipids

    Antunes, P. A.; Oliveira, O. N.; Aroca, R. F.; Chierice, G. O.; Constantino, C. J. L.

    2005-06-01

    In this work, we investigate Langmuir monolayers from an amide extracted from dried roots of Ottonia propinqua, a native Brazilian plant believed to exhibit anesthetic and hallucinogen activities. In addition to producing monolayers from the amide itself, we probe the molecular-level action of the amide on phospholipids employed as simple membrane models. The surface pressure-molecular area ( π- A) isotherms for the amide were little affected by a number of subphase conditions. Almost no changes were observed upon varying the compression speed, spreading volume onto the surface, ions in the subphase, ionic strength and the solution solvent. However, stronger effects occurred when the subphase temperature and pH were altered, as the isotherms were shifted to larger areas with increasing temperatures and decreasing pHs. These results are discussed in terms of the molecular packing adopted by the amide at the air-water interface. In the mixed films with arachidic acid, the area per molecule varied linearly with the concentration of amide, probably due to phase separation. On the other hand, in the mixed films with dipalmitoyl phosphatidyl choline (DPPC), small amounts of the amide were sufficient to change the π- A isotherms significantly. This points to a strong molecular-level interaction, probably between the phosphate group in the zwitterion of DPPC and the nitrogen from the amidic group.

  18. A Novel Saponin Hydrolase from Neocosmospora vasinfecta var. vasinfecta

    Watanabe, Manabu; Sumida, Naomi; Yanai, Koji; Murakami, Takeshi

    2004-01-01

    We isolated a soybean saponin hydrolase from Neocosmospora vasinfecta var. vasinfecta PF1225, a filamentous fungus that can degrade soybean saponin and generate soyasapogenol B. This enzyme was found to be a monomer with a molecular mass of about 77 kDa and a glycoprotein. Nucleotide sequence analysis of the corresponding gene (sdn1) indicated that this enzyme consisted of 612 amino acids and had a molecular mass of 65,724 Da, in close agreement with that of the apoenzyme after the removal of...

  19. Isolation, purification and characterization of a new organphosphorus hydrolase OPHC2

    WU Ningfeng; DENG Minjie; SHI Xiuyun; LIANG Guoyi; YAO Bin; FAN Yunliu

    2004-01-01

    A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoalcaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified and characterized. OPHC2 has optimum activity for the reaction at 65℃ and pH 9.0 with methyl parathion as a substrate, it also shows good thermal and pH stability. Most metal ions and chemicals have no effect on the activity of OPHC2. The analyses of nucleotide sequence encoding OPHC2 and amino acid sequence of OPHC2 show that there are lower homologies with those of organphosphorus hydrolase reported in GenBank.

  20. Structure-guided engineering of molinate hydrolase for the degradation of thiocarbamate pesticides.

    José P Leite

    Full Text Available Molinate is a recalcitrant thiocarbamate used to control grass weeds in rice fields. The recently described molinate hydrolase, from Gulosibacter molinativorax ON4T, plays a key role in the only known molinate degradation pathway ending in the formation of innocuous compounds. Here we report the crystal structure of recombinant molinate hydrolase at 2.27 Å. The structure reveals a homotetramer with a single mononuclear metal-dependent active site per monomer. The active site architecture shows similarities with other amidohydrolases and enables us to propose a general acid-base catalysis mechanism for molinate hydrolysis. Molinate hydrolase is unable to degrade bulkier thiocarbamate pesticides such as thiobencarb which is used mostly in rice crops. Using a structural-based approach, we were able to generate a mutant (Arg187Ala that efficiently degrades thiobencarb. The engineered enzyme is suitable for the development of a broader thiocarbamate bioremediation system.

  1. Genetically reduced soluble epoxide hydrolase activity and risk of stroke and other cardiovascular disease

    Lee, Julie; Dahl, Morten; Grande, Peer; Tybjaerg-Hansen, Anne; Nordestgaard, Børge G

    2010-01-01

    BACKGROUND AND PURPOSE: The development of stroke has been linked to lowered levels of epoxyeicosatrienoic acids in the cerebral microvasculature. These substances are metabolized by the enzyme-soluble epoxide hydrolase encoded by the EPHX2 gene. We tested whether genetically reduced soluble...... epoxide hydrolase activity is associated with risk of ischemic stroke, myocardial infarction, and ischemic heart disease. METHODS: We genotyped participants from the Copenhagen City Heart Study (n=10 352), the Copenhagen General Population Study (n=26 042), the Copenhagen Carotid Stroke Study (n=398 cases......=0.08 to 1.00). Similar results were obtained for myocardial infarction and ischemic heart disease in the 3 studies. CONCLUSIONS: Our results show with significant power that genetically reduced soluble epoxide hydrolase activity is not a major risk factor for ischemic stroke, myocardial infarction...

  2. Bifunctional Brønsted Base Catalyzes Direct Asymmetric Aldol Reaction of α-Keto Amides.

    Echave, Haizea; López, Rosa; Palomo, Claudio

    2016-03-01

    The first enantioselective direct cross-aldol reaction of α-keto amides with aldehydes, mediated by a bifunctional ureidopeptide-based Brønsted base catalyst, is described. The appropriate combination of a tertiary amine base and an aminal, and urea hydrogen-bond donor groups in the catalyst structure promoted the exclusive generation of the α-keto amide enolate which reacted with either non-enolizable or enolizable aldehydes to produce highly enantioenriched polyoxygenated aldol adducts without side-products resulting from dehydration, α-keto amide self-condensation, aldehyde enolization, and isotetronic acid formation. PMID:26835655

  3. Structure Determination and Characterization of the Vitamin B[superscript 6] Degradative Enzyme (E)-2-(Acetamidomethylene)succinate Hydrolase

    McCulloch, Kathryn M.; Mukherjee, Tathagata; Begley, Tadhg P.; Ealick, Steven E. (Cornell); (TAM)

    2010-06-22

    The gene identification and kinetic characterization of (E)-2-(acetamidomethylene)succinate (E-2AMS) hydrolase has recently been described. This enzyme catalyzes the final reaction in the degradation of vitamin B{sub 6} and produces succinic semialdehyde, acetate, ammonia, and carbon dioxide from E-2AMS. The structure of E-2AMS hydrolase was determined to 2.3 {angstrom} using SAD phasing. E-2AMS hydrolase is a member of the {alpha}/{beta} hydrolase superfamily and utilizes a serine/histidine/aspartic acid catalytic triad. Mutation of either the nucleophilic serine or the aspartate resulted in inactive enzyme. Mutation of an additional serine residue in the active site causes the enzyme to be unstable and is likely structurally important. The structure also provides insight into the mechanism of hydrolysis of E-2AMS and identifies several potential catalytically important residues.

  4. Optimization of amide-based EP3 receptor antagonists.

    Lee, Esther C Y; Futatsugi, Kentaro; Arcari, Joel T; Bahnck, Kevin; Coffey, Steven B; Derksen, David R; Kalgutkar, Amit S; Loria, Paula M; Sharma, Raman

    2016-06-01

    Prostaglandin E receptor subtype 3 (EP3) antagonism may treat a variety of symptoms from inflammation to cardiovascular and metabolic diseases. Previously, most EP3 antagonists were large acidic ligands that mimic the substrate, prostaglandin E2 (PGE2). This manuscript describes the optimization of a neutral small molecule amide series with improved lipophilic efficiency (LipE) also known as lipophilic ligand efficiency (LLE) ((a) Nat. Rev. Drug Disc.2007, 6, 881; (b) Annu. Rep. Med. Chem.2010, 45, 380). PMID:27107947

  5. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Styrene

    Hasmukh S. Patel; Panchal, Kumar K.

    2004-01-01

    Novel unsaturated poly (ester-amide) resins (UPEAs) were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA) and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Styrene (STY.) to produce a homogeneous resin syrup. The curing of these UPEAs-STY. resin blends was carried out by using benzoyl peroxide (BPO) as a catalyst and was monitored by using a differential scanning calorimeter ...

  6. Synthesis and characterization of alternating poly(amide urethane)s

    Sharma, Bhaskar

    2004-01-01

    This thesis deals with the preparation of alternating poly(amide urethane)s which might be of interest for the manufacture of powder coatings. The synthesis of poly(amide urethane)s was performed in environmentally friendly way without using isocyanates or phosgene. The starting materials for the synthesis were e-caprolactam, e-caprolactone, amino alcohols, diamines and carbonic acid derivatives, i.e. diphenyl carbonate and ethylene carbonate as substitutes for phosgene. A new synthesis was d...

  7. Zirconyl chloride promoted highly efficient solid phase synthesis of amide derivatives

    2007-01-01

    An efficient solid phase route for the synthesis of amide derivatives by the reaction of carboxylic acids with urea in the presence of catalytic amount of zirconyl chloride under microwave irradiation conditions was described. In this way, a range of interesting amide derivatives was obtained in good to excellent yields. The catalyst was recycled with fresh reactants and it gave almost similar results without significant loss of activity up to the third run.

  8. Soluble epoxide hydrolase: A potential target for metabolic diseases.

    He, Jinlong; Wang, Chunjiong; Zhu, Yi; Ai, Ding

    2016-05-01

    Epoxyeicosatrienoic acids (EETs), important lipid mediators derived from arachidonic acid, have many beneficial effects in metabolic diseases, including atherosclerosis, hypertension, cardiac hypertrophy, diabetes, non-alcoholic fatty liver disease, and kidney disease. Epoxyeicosatrienoic acids can be further hydrolyzed to less active diols by the enzyme soluble epoxide hydrolase (sEH). Increasing evidence suggests that inhibition of sEH increases levels of EETs, which have anti-inflammatory effects and can prevent the development of hypertension, atherosclerosis, heart failure, fatty liver, and multiple organ fibrosis. Arachidonic acid is the most abundant omega-6 polyunsaturated fatty acid (PUFA) and shares the same set of enzymes with omega-3 PUFAs, such as docosahexaenoic acid and eicosapentaenoic acid. The omega-3 PUFAs and metabolites, such as regioisomeric epoxyeicosatetraenoic acids and epoxydocosapentaenoic acids, have been reported to have strong vasodilatory and anti-inflammatory effects. Therefore, sEH may be a potential therapeutic target for metabolic disorders. In this review, we focus on our and other recent studies of the functions of sEH, including the effects of its eicosanoid products from both omega-3 and omega-6 PUFAs, in various metabolic diseases. We also discuss the possible cellular and molecular mechanisms underlying the regulation of sEH. PMID:26621325

  9. Orientation Preferences of Backbone Secondary Amide Functional Groups in Peptide Nucleic Acid Complexes: Quantum Chemical Calculations Reveal an Intrinsic Preference of Cationic D-Amino Acid-Based Chiral PNA Analogues for the P-form

    Topham, Christopher M.; Smith, Jeremy C.

    2006-01-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like basepair stacking. Quantum chemical calculations on the bindin...

  10. Active site and laminarin binding in glycoside hydrolase family 55.

    Bianchetti, Christopher M; Takasuka, Taichi E; Deutsch, Sam; Udell, Hannah S; Yik, Eric J; Bergeman, Lai F; Fox, Brian G

    2015-05-01

    The Carbohydrate Active Enzyme (CAZy) database indicates that glycoside hydrolase family 55 (GH55) contains both endo- and exo-β-1,3-glucanases. The founding structure in the GH55 is PcLam55A from the white rot fungus Phanerochaete chrysosporium (Ishida, T., Fushinobu, S., Kawai, R., Kitaoka, M., Igarashi, K., and Samejima, M. (2009) Crystal structure of glycoside hydrolase family 55 β-1,3-glucanase from the basidiomycete Phanerochaete chrysosporium. J. Biol. Chem. 284, 10100-10109). Here, we present high resolution crystal structures of bacterial SacteLam55A from the highly cellulolytic Streptomyces sp. SirexAA-E with bound substrates and product. These structures, along with mutagenesis and kinetic studies, implicate Glu-502 as the catalytic acid (as proposed earlier for Glu-663 in PcLam55A) and a proton relay network of four residues in activating water as the nucleophile. Further, a set of conserved aromatic residues that define the active site apparently enforce an exo-glucanase reactivity as demonstrated by exhaustive hydrolysis reactions with purified laminarioligosaccharides. Two additional aromatic residues that line the substrate-binding channel show substrate-dependent conformational flexibility that may promote processive reactivity of the bound oligosaccharide in the bacterial enzymes. Gene synthesis carried out on ∼30% of the GH55 family gave 34 active enzymes (19% functional coverage of the nonredundant members of GH55). These active enzymes reacted with only laminarin from a panel of 10 different soluble and insoluble polysaccharides and displayed a broad range of specific activities and optima for pH and temperature. Application of this experimental method provides a new, systematic way to annotate glycoside hydrolase phylogenetic space for functional properties. PMID:25752603

  11. Development of an efficient 18O epoxide labeling method: Investigation of the cytosolic expoxide hydrolase mechanism

    Mechanistic studies of Cytosolic Epoxide Hydrolase (CEH) reveal an anti opening of the epoxide arising from base catalyzed activation of H2O, possibly in concert with acidic activation of the epoxide oxygen. Preliminary data on the hydrolysis of fatty acid oxides shows the CEH is able to discriminate between chemically equivalent epoxide carbons. The research is geared toward methodology development in which CEH could be used as a organic synthetic tool, with substrate and product regio-, stereo-, and enantioselectivity

  12. Efficient Calculation of Enzyme Reaction Free Energy Profiles Using a Hybrid Differential Relaxation Algorithm: Application to Mycobacterial Zinc Hydrolases.

    Romero, Juan Manuel; Martin, Mariano; Ramirez, Claudia Lilián; Dumas, Victoria Gisel; Marti, Marcelo Adrián

    2015-01-01

    Determination of the free energy profile for an enzyme reaction mechanism is of primordial relevance, paving the way for our understanding of the enzyme's catalytic power at the molecular level. Although hybrid, mostly DFT-based, QM/MM methods have been extensively applied to this type of studies, achieving accurate and statistically converged results at a moderate computational cost is still an open challenge. Recently, we have shown that accurate results can be achieved in less computational time, combining Jarzynski's relationship with a hybrid differential relaxation algorithm (HyDRA), which allows partial relaxation of the solvent during the nonequilibrium steering of the reaction. In this work, we have applied this strategy to study two mycobacterial zinc hydrolases. Mycobacterium tuberculosis infections are still a worldwide problem and thus characterization and validation of new drug targets is an intense field of research. Among possible drug targets, recently two essential zinc hydrolases, MshB (Rv1170) and MA-amidase (Rv3717), have been proposed and structurally characterized. Although possible mechanisms have been proposed by analogy to the widely studied human Zn hydrolases, several key issues, particularly those related to Zn coordination sphere and its role in catalysis, remained unanswered. Our results show that mycobacterial Zn hydrolases share a basic two-step mechanism. First, the attacking water becomes deprotonated by the conserved base and establishes the new C-O bond leading to a tetrahedral intermediate. The intermediate requires moderate reorganization to allow for proton transfer to the amide N and C-N bond breaking to occur in the second step. Zn ion plays a key role in stabilizing the tetrahedral intermediate and balancing the negative charge of the substrate during hydroxide ion attack. Finally, comparative analysis of other Zn hydrolases points to a convergent mechanistic evolution. PMID:26415840

  13. Supercritical fluid extraction of uranium and thorium employing dialkyl amides

    Extraction and purification of actinides from different matrices is of utmost importance to the nuclear industry. In recent decades, supercritical fluid extraction (SFE) has emerged as a promising alternative to solvent extraction owing to its inherent potential of minimization of liquid waste generation. N,N-dialkyl aliphatic amides have been proposed to be an alternative to TBP in the reprocessing of spent nuclear fuel due to several attractive features like innocuous nature of degradation products (mainly carboxylic acids/ amines), possibility of complete incineration of the used extractant leading to reduction in volume of secondary waste. Also, physico-chemical properties of this class of extractants can be tuned by the judicious choice of alkyl groups. In the present work, N,N-dialkyl aliphatic amides with varying alkyl groups viz. N,N-dibutyl-2-ethylhexanamide (DBEHA), N,N-dibutyl-3,3-dimethylbutanamide (DBDMBA), N,N-dihexyloctanamide (DHOA), N,N-disecbutylpentamide (DBPA), N,N-dibutyloctanamide (DBOA), have been evaluated for supercritical fluid extraction (SFE) of uranium and thorium from nitric acid medium as well as tissue paper matrix. Amides were obtained from Department of Chemistry, Delhi University and were used as such. This fact could be exploited for separation of thorium and uranium

  14. Characterization and purification of bile salt hydrolase from Lactobacillus sp. strain 100-100

    The authors have characterized and purified the bile salt hydrolase from Lactobacillus sp. strain 100-100. Bile salt hydrolase from cells of the strain was purified with column and high-performance liquid chromatography. The activity was assayed in whole cells and cell-free extracts with either a radiochemical assay involving [14C]taurocholic acid or a nonradioactive assay involving trinitrobenzene sulfonate. The activity was detectable only in stationary-phase cells. Within 20 min after conjugated bile acids were added to stationary-phase cultures of strain 100-100, the activity in whole cells increased to levels three- to fivefold higher than in cells from cultures grown in medium free of bile salts. In cell-free extracts, however, the activity was about equal whether or not the cells have been grown with bile salts present. When supernatant solutions from cultures grown in medium containing taurocholic acid were used to suspend cells grown in medium free of the bile salt, the bile salt hydrolase activity detected in whole cells increased two- to threefold. Two forms of the hydrolase were purified from the cells and designated hydrolases A and B. They eluted from anion-exchange high-performance liquid chromatography in two sets of fractions, A at 0.15 M NaCl and B at 0.18 M NaCl. Their apparent molecular weights in nondenaturing polyacrylamide gel electrophoresis were 115,000 and 105,000, respectively. However, discrepancies existed in the apparent molecular weights and number of peptides detected in sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the two forms. Whether the enzyme exists in two forms in the cells remains to be determined

  15. A two-step approach to achieve secondary amide transamidation enabled by nickel catalysis

    Baker, Emma L.; Yamano, Michael M.; Zhou, Yujing; Anthony, Sarah M.; Garg, Neil K.

    2016-01-01

    A long-standing challenge in synthetic chemistry is the development of the transamidation reaction. This process, which involves the conversion of one amide to another, is typically plagued by unfavourable kinetic and thermodynamic factors. Although some advances have been made with regard to the transamidation of primary amide substrates, secondary amide transamidation has remained elusive. Here we present a simple two-step approach that allows for the elusive overall transformation to take place using non-precious metal catalysis. The methodology proceeds under exceptionally mild reaction conditions and is tolerant of amino-acid-derived nucleophiles. In addition to overcoming the classic problem of secondary amide transamidation, our studies expand the growing repertoire of new transformations mediated by base metal catalysis. PMID:27199089

  16. Orientation Preferences of Backbone Secondary Amide Functional Groups in Peptide Nucleic Acid Complexes: Quantum Chemical Calculations Reveal an Intrinsic Preference of Cationic D-Amino Acid-Based Chiral PNA Analogues for the P-form

    Smith, Jeremy C [ORNL; Topham, Christopher [University of Heidelberg

    2007-01-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like base pair stacking. Quantum chemical calculations on the binding of a water molecule to an O2 base atom in glycine-based PNA thymine dimers indicate that junctions modeled with P-form backbone conformations are lower in energy than a dimer comprising the predominant conformation observed in A-like helices. It is further shown in model systems that PNA analogs based on D-lysine are better able to preorganize in a conformation exclusive to P-form helices than is glycine-based PNA. An intrinsic preference for this conformation is also exhibited by positively charged chiral PNA dimers carrying 3-amino-D-alanine or 4-aza-D-leucine residue units that provide for additional rigidity by side-chain hydrogen bonding to the backbone carbonyl oxygen. Structural modifications stabilizing P-form helices may obviate the need for large heterocycles to target DNA pyrimidine bases via PNADNA-PNA triplex formation. Quantum chemical modeling methods are used to propose candidate PNA Hoogsteen strand designs.

  17. Orientation preferences of backbone secondary amide functional groups in peptide nucleic acid complexes: quantum chemical calculations reveal an intrinsic preference of cationic D-amino acid-based chiral PNA analogues for the P-form.

    Topham, Christopher M; Smith, Jeremy C

    2007-02-01

    Geometric descriptions of nonideal interresidue hydrogen bonding and backbone-base water bridging in the minor groove are established in terms of polyamide backbone carbonyl group orientation from analyses of residue junction conformers in experimentally determined peptide nucleic acid (PNA) complexes. Two types of interresidue hydrogen bonding are identified in PNA conformers in heteroduplexes with nucleic acids that adopt A-like basepair stacking. Quantum chemical calculations on the binding of a water molecule to an O2 base atom in glycine-based PNA thymine dimers indicate that junctions modeled with P-form backbone conformations are lower in energy than a dimer comprising the predominant conformation observed in A-like helices. It is further shown in model systems that PNA analogs based on D-lysine are better able to preorganize in a conformation exclusive to P-form helices than is glycine-based PNA. An intrinsic preference for this conformation is also exhibited by positively charged chiral PNA dimers carrying 3-amino-D-alanine or 4-aza-D-leucine residue units that provide for additional rigidity by side-chain hydrogen bonding to the backbone carbonyl oxygen. Structural modifications stabilizing P-form helices may obviate the need for large heterocycles to target DNA pyrimidine bases via PNA.DNA-PNA triplex formation. Quantum chemical modeling methods are used to propose candidate PNA Hoogsteen strand designs. PMID:17071666

  18. Mechanistic insight into benzenethiol catalyzed amide bond formations from thioesters and primary amines

    Stuhr-Hansen, Nicolai; Bork, Nicolai; Strømgaard, Kristian

    2014-01-01

    The influence of arylthiols on cysteine-free ligation, i.e. the reaction between an alkyl thioester and a primary amine forming an amide bond, was studied in a polar aprotic solvent. We reacted the ethylthioester of hippuric acid with cyclohexylamine in the absence or presence of various quantities...... state in the aromatic thioester amidation reaction. Under similar conditions, cysteine-free ligation was achieved by coupling a fully side-chain protected 15 amino acid phosphopeptide thioester to the free N-terminal of a side-chain protected 9 amino acid peptide producing the corresponding 24 amino...... of thiophenol (PhSH) in a slurry of disodium hydrogen phosphate in dry DMF. Quantitative conversions into the resulting amide were observed within a few hours in the presence of equimolar amounts of thiophenol. Ab initio calculations showed that the reaction mechanism in DMF is similar to the well...

  19. Characteristics, protein engineering and applications of microbial thermostable pullulanases and pullulan hydrolases.

    Nisha, M; Satyanarayana, T

    2016-07-01

    Pullulan hydrolyzing enzymes are endoacting, classified based on the substrate specificity and hydrolysis products as pullulanases (type I and II) and pullulan hydrolases (type I, II and III). Pullulanases and pullulan hydrolase type I are produced by bacteria and archaea. Among bacteria, many mesophilic, thermophilic and hyperthermophilic bacteria produce pullulanases and neopullulanases. While pullulan hydrolase type II and type III are produced by fungi and archaea, respectively. These are multi-domain proteins with three conserved catalytic acidic residues of the glycosyl hydrolases. The recent advances in molecular biology and protein engineering via mutagenesis and truncation led to improvement in thermostability, catalytic activity and substrate specificity. Pullulanases are debranching enzymes, which are widely employed in starch saccharification that minimizes the use of glucoamylase (approx. 50 %) and reduces the total reaction time of the industrial starch conversion process. The thermostable amylopullulanases are useful in one-step starch liquefaction and saccharification, which replaces amylolytic enzymes like α-amylase and glucoamylase, thus resulting in the reduction in the cost of sugar production. The enzymes also find application in making resistant starches and as an antistale in bread making. Panose and isopanose containing syrups are useful as prebiotics, while panose has also been reported to display anticarcinogenic activity. This review focuses on the distinguishing features of these enzymes based on the analysis of amino acid sequences and domain structure, besides highlighting recent advances in the molecular biology and protein engineering for enhancing their thermostability, catalytic activity and substrate specificity. This review also briefly summarizes the potential applications of pullulanases and pullulan hydrolases. PMID:27142298

  20. Novel endogenous N-acyl amides activate TRPV1-4 receptors, BV-2 microglia, and are regulated in brain in an acute model of inflammation

    Siham eRaboune

    2014-08-01

    Full Text Available A family of endogenous lipids, structurally analogous to the endogenous cannabinoid, N-arachidonoyl ethanolamine (Anandamide, and called N-acyl amides have emerged as a family of biologically active compounds at TRP receptors. N-acyl amides are constructed from an acyl group and an amine via an amide bond. This same structure can be modified by changing either the fatty acid or the amide to form potentially hundreds of lipids. More than 70 N-acyl amides have been identified in nature. We have ongoing studies aimed at isolating and characterizing additional members of the family of N-acyl amides in both central and peripheral tissues in mammalian systems. Here, using a unique in-house library of over 70 N-acyl amides we tested the following three hypotheses: 1 Additional N-acyl amides will have activity at TRPV1-4, 2 Acute peripheral injury will drive changes in CNS levels of N-acyl amides, and 3 N-acyl amides will regulate calcium in CNS-derived microglia. Through these studies, we have identified 20 novel N-acyl amides that collectively activate (stimulating or inhibiting TRPV1-4. Using lipid extraction and HPLC coupled to tandem mass spectrometry we showed that levels of at least 10 of these N-acyl amides that activate TRPVs are regulated in brain after intraplantar carrageenan injection. We then screened the BV2 microglial cell line for activity with this N-acyl amide library and found overlap with TRPV receptor activity as well as additional activators of calcium mobilization from these lipids. Together these data provide new insight into the family of N-acyl amides and their roles as signaling molecules at ion channels, in microglia, and in the brain in the context of inflammation.

  1. Structure of the minimized α/β-hydrolase fold protein from Thermus thermophilus HB8

    The crystal structure of the minimized α/β-hydrolase fold protein encoded by the gene TTHA1544 from T. thermophilus HB8 has been determined at 2.0 Å resolution. The gene encoding TTHA1544 is a singleton found in the Thermus thermophilus HB8 genome and encodes a 131-amino-acid protein. The crystal structure of TTHA1544 has been determined at 2.0 Å resolution by the single-wavelength anomalous dispersion method in order to elucidate its function. There are two molecules in the asymmetric unit. Each molecule consists of four α-helices and six β-strands, with the β-strands composing a central β-sheet. A structural homology search revealed that the overall structure of TTHA1544 resembles the α/β-hydrolase fold, although TTHA1544 lacks the catalytic residues of a hydrolase. These results suggest that TTHA1544 represents the minimized α/β-hydrolase fold and that an additional component would be required for its activity

  2. Novel carbon-11 labeled 4-dimethylamino-but-2-enoic acid [4-(phenylamino)-quinazoline-6-yl]-amides: potential PET bioprobes for molecular imaging of EGFR-positive tumors

    We have previously reported of labeled reversible and irreversible EGFR inhibitors, such as 4-(3,4-dichloro-6-fluoroanilino)-6,7-dimethoxyquinazoline (ML01) and 6-acrylamido-4-(3,4-dichloro-6-fluoroanilino)quinazoline (ML03), to be suboptimal as imaging agents. On the basis of these studies, a new generation of novel, more chemically stable irreversible inhibitors was labeled with carbon-11 as potential positron emission tomography (PET) biomarkers for molecular imaging of epidermal growth factor receptor (EGFR)-positive tumors. In these new labeled, irreversible inhibitors the acryl-amide group at the 6-position of the quinazoline ring was replaced with a 4-dimethylamino-but-2-enoic amide. The nonlabeled compounds were evaluated in vitro to determine their EGFR autophosphorylation IC50 values. The IC50 values indicated that these new irreversible compounds possess similar potencies towards the EGFR, as the parent compound, ML03. These compounds were labeled with carbon-11 at the dimethylamine moiety, using the well known labeling reagent C-11 MeI. The labeling procedure was automated using a commercial module. The final products were obtained with 10% decay corrected radiochemical yield, 99% radiochemical purity, 96% chemical purity, and a high specific activity of 2.7 Ci/μmol EOB. The high potency of these new labeled bioprobes towards the EGFR establishes their potential to serve as PET agents for molecular imaging of EGFR-positive tumors

  3. The grafting and release behavior of doxorubincin from Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles via an acid cleaving amide bond: the potential for magnetic targeting drug delivery

    Chen, F H; Gao, Q; Ni, J Z [State Key Laboratory of Rare Earth Resources and Application, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)], E-mail: jzni@ciac.jl.cn

    2008-04-23

    Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles were first prepared and characterized by TEM, FTIR, XPS and XRD. Subsequently the widely used anticancer agent doxorubincin (DOX) was successfully grafted to the surface of the core-shell nanoparticles via an amide bond with the aid of a spacer arm we synthesized. The spacer arm met two needs: one end can couple to the core-shell nanoparticles' surface while the other end was the active -COOH group, which can react with the -NH{sub 2} group of DOX molecules. The synthesized spacer arm and the conjugation of the drug with nanoparticles through amidation were confirmed by FTIR. The DOX-loading efficiency determined by UV-vis spectrometer was 86.5%. Drug release experiments displayed a pH-dependent behavior that DOX was cleaved from the nanoparticles easily under low pH conditions in the presence of protease and that most of the conjugated doxorubincin were released within the first 12 h. The prepared DOX-grafted Fe{sub 3}O{sub 4}-SiO{sub 2} core-shell structure nanoparticles showed a superparamagnetic property with a saturation magnetization value of 49.3 emu g{sup -1}, indicating a great potential application in the treatment of cancer using magnetic targeting drug-delivery technology.

  4. First synthesis and anticancer activity of novel naphthoquinone amides.

    Pradidphol, Narathip; Kongkathip, Ngampong; Sittikul, Pichamon; Boonyalai, Nonlawat; Kongkathip, Boonsong

    2012-03-01

    Sixteen novel naphthoquinone aromatic amides were synthesized by a new route starting from 1-hydroxy-2-naphthoic acid in nine or ten steps with good to excellent yield. Amide formation reaction was carried out by using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) as an efficient condensing agent leading to carboxamides in high yield. The key step for converting naphthol to 3-hydroxynaphthoquinone was the Fremy's salt oxidation followed by hydroxylation with tert-butyl hydroperoxide and triton B. Anticancer activity of these new naphthoquinone amides were evaluated and benzamide 22 showed potent inhibition against NCI-H187 cell lines while naphthamides 23 and 43 were the most potent inhibition against KB cells. The decatenation assay revealed that compounds 24 and 43 at 20 μM can inhibit hTopoIIα activity while three other compounds, namely compounds 22, 23, and 45, exhibited hTopoIIα inhibitory activity at final concentration of 50 μM. Docking experiment revealed the same trend as the cytotoxicity and decatenation assay. Therefore, naphthamides 24 and 43 can be promising target molecules for anticancer drug development. PMID:22280818

  5. Amide functionalized MWNT/SPEEK composite membrane for better electrochemical performance

    Gahlot, Swati; Sharma, Prem P.; Kulshrestha, Vaibhav

    2016-05-01

    Nanocomposite membranes based on multiwalled carbon nanotube /SPEEK (sulfonated poly ether ether ketone) have been synthesized via simple solution casting. Prior to use CNT have been purified and grafted with carboxylic acid groups onto its walls by means of sulfuric and nitric acid. Afterwards, amidation of carboxylated CNTs (c-CNT) has been done. Amidated CNT (a-CNT) is then incorporated in SPEEK polymer matrix to synthesize nanocomposite membranes. Physicochemical, structural, thermal and mechanical characterizations are done through the respective techniques. Electric and ionic conductivities have also been evaluated. Composites membranes show the enhanced electrochemical performance with higher electric conductivity.

  6. Alpha-amidated peptides derived from pro-opiomelanocortin in normal human pituitary

    Fenger, M; Johnsen, A H

    1988-01-01

    Normal human pituitaries were extracted in boiling water and acetic acid, and the alpha-amidated peptide products of pro-opiomelanocortin (POMC), alpha-melanocyte-stimulating hormone (alpha MSH), gamma-melanocyte-stimulating hormone (gamma 1MSH), and amidated hinge peptide (HP-N), as well as their...... glycine-extended precursors, were characterized by sequence-specific radioimmunoassays, gel-chromatography, h.p.l.c. and amino acid sequencing. alpha MSH and gamma 1MSH constituted 0.27-1.32% and 0.10-5.10%, respectively, of the POMC-derived products [calculated as the sum of adrenocorticotropic hormone...

  7. Structure-property relationship of aliphatic segmented poly(ester amide)s

    Garg, Priya

    2010-01-01

    This thesis focuses on the synthesis, characterization and applications of aliphatic segmented poly(ester amide)s (PEA)s for use as potential biomaterials. Three different series of PEAs with different microstructures containing isolated, two and three adjacent amide groups within a polybutylene adipate (PBA) chain have been synthesized. Analytical techniques such as NMR (liquid and solid-state), SEC, DSC, FT-IR, WAXD and microscopy (AFM, SEM, optical) have been extensively used to characteri...

  8. Orthogonal dipolar interactions between amide carbonyl groups

    Fischer, Felix R.; Wood, Peter A.; Allen, Frank H; Diederich, François

    2008-01-01

    Orthogonal dipolar interactions between amide C=O bond dipoles are commonly found in crystal structures of small molecules, proteins, and protein–ligand complexes. We herein present the experimental quantification of such interactions by employing a model system based on a molecular torsion balance. Application of a thermodynamic double-mutant cycle allows for the determination of the incremental energetic contributions attributed to the dipolar contact between 2 amide C=O groups. The stabili...

  9. GENETIC VARIATION IN SOLUBLE EPOXIDE HYDROLASE (EPHX2) IS ASSOCIATED WITH FOREARM VASODILATOR RESPONSES IN HUMANS

    Lee, Craig R.; Pretorius, Mias; Schuck, Robert N.; Burch, Lauranell H.; Bartlett, Jackie; Williams, Scott M.; ZELDIN, DARRYL C.; Brown, Nancy J.

    2010-01-01

    Cytochrome P450-derived epoxyeicosatrienoic acids are potent vasodilators in preclinical models and are hydrolyzed by soluble epoxide hydrolase (EPHX2). Associations between the EPHX2 Lys55Arg and Arg287Gln polymorphisms and cardiovascular disease risk have been reported; however, their impact on vascular function in humans has not been investigated. In 265 volunteers (198 white, 67 black American), forearm blood flow was measured by strain-gauge venous occlusion plethysmography at baseline a...

  10. Soluble Epoxide Hydrolase Inhibition: Targeting Multiple Mechanisms of Ischemic Brain Injury with a Single Agent

    Iliff, Jeffrey J.; Alkayed, Nabil J.

    2009-01-01

    Soluble epoxide hydrolase (sEH) is a key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids (EETs). Genetic variations in the sEH gene, designated EPHX2, are associated with ischemic stroke risk. In experimental studies, sEH inhibition and gene deletion reduce infarct size after focal cerebral ischemia in mice. Although the precise mechanism of protection afforded by sEH inhibition remains under investigation, EETs exhibit a wide array of p...

  11. Soluble epoxide hydrolase inhibition and gene deletion are protective against myocardial ischemia-reperfusion injury in vivo

    Motoki, Atsuko; Merkel, Matthias J.; Packwood, William H.; Cao, Zhiping; Liu, Lijuan; Iliff, Jeffrey; Alkayed, Nabil J.; Van Winkle, Donna M.

    2008-01-01

    Soluble epoxide hydrolase (sEH) metabolizes epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids. EETs are formed from arachidonic acid during myocardial ischemia and play a protective role against ischemic cell death. Deletion of sEH has been shown to be protective against myocardial ischemia in the isolated heart preparation. We tested the hypothesis that sEH inactivation by targeted gene deletion or pharmacological inhibition reduces infarct size (I) after regional myocardial ...

  12. Molecular Identification of β-Citrylglutamate Hydrolase as Glutamate Carboxypeptidase 3*

    Collard, François; Vertommen, Didier; Constantinescu, Stefan; Buts, Lieven; Van Schaftingen, Emile

    2011-01-01

    β-Citrylglutamate (BCG), a compound present in adult testis and in the CNS during the pre- and perinatal periods is synthesized by an intracellular enzyme encoded by the RIMKLB gene and hydrolyzed by an as yet unidentified ectoenzyme. To identify β-citrylglutamate hydrolase, this enzyme was partially purified from mouse testis and characterized. Interestingly, in the presence of Ca2+, the purified enzyme specifically hydrolyzed β-citrylglutamate and did not act on N-acetyl-aspartylglutamate (NAAG). However, both compounds were hydrolyzed in the presence of Mn2+. This behavior and the fact that the enzyme was glycosylated and membrane-bound suggested that β-citrylglutamate hydrolase belonged to the same family of protein as glutamate carboxypeptidase 2 (GCP2), the enzyme that catalyzes the hydrolysis of N-acetyl-aspartylglutamate. The mouse tissue distribution of β-citrylglutamate hydrolase was strikingly similar to that of the glutamate carboxypeptidase 3 (GCP3) mRNA, but not that of the GCP2 mRNA. Furthermore, similarly to β-citrylglutamate hydrolase purified from testis, recombinant GCP3 specifically hydrolyzed β-citrylglutamate in the presence of Ca2+, and acted on both N-acetyl-aspartylglutamate and β-citrylglutamate in the presence of Mn2+, whereas recombinant GCP2 only hydrolyzed N-acetyl-aspartylglutamate and this, in a metal-independent manner. A comparison of the structures of the catalytic sites of GCP2 and GCP3, as well as mutagenesis experiments revealed that a single amino acid substitution (Asn-519 in GCP2, Ser-509 in GCP3) is largely responsible for GCP3 being able to hydrolyze β-citrylglutamate. Based on the crystal structure of GCP3 and kinetic analysis, we propose that GCP3 forms a labile catalytic Zn-Ca cluster that is critical for its β-citrylglutamate hydrolase activity. PMID:21908619

  13. Molecular identification of β-citrylglutamate hydrolase as glutamate carboxypeptidase 3.

    Collard, François; Vertommen, Didier; Constantinescu, Stefan; Buts, Lieven; Van Schaftingen, Emile

    2011-11-01

    β-Citrylglutamate (BCG), a compound present in adult testis and in the CNS during the pre- and perinatal periods is synthesized by an intracellular enzyme encoded by the RIMKLB gene and hydrolyzed by an as yet unidentified ectoenzyme. To identify β-citrylglutamate hydrolase, this enzyme was partially purified from mouse testis and characterized. Interestingly, in the presence of Ca(2+), the purified enzyme specifically hydrolyzed β-citrylglutamate and did not act on N-acetyl-aspartylglutamate (NAAG). However, both compounds were hydrolyzed in the presence of Mn(2+). This behavior and the fact that the enzyme was glycosylated and membrane-bound suggested that β-citrylglutamate hydrolase belonged to the same family of protein as glutamate carboxypeptidase 2 (GCP2), the enzyme that catalyzes the hydrolysis of N-acetyl-aspartylglutamate. The mouse tissue distribution of β-citrylglutamate hydrolase was strikingly similar to that of the glutamate carboxypeptidase 3 (GCP3) mRNA, but not that of the GCP2 mRNA. Furthermore, similarly to β-citrylglutamate hydrolase purified from testis, recombinant GCP3 specifically hydrolyzed β-citrylglutamate in the presence of Ca(2+), and acted on both N-acetyl-aspartylglutamate and β-citrylglutamate in the presence of Mn(2+), whereas recombinant GCP2 only hydrolyzed N-acetyl-aspartylglutamate and this, in a metal-independent manner. A comparison of the structures of the catalytic sites of GCP2 and GCP3, as well as mutagenesis experiments revealed that a single amino acid substitution (Asn-519 in GCP2, Ser-509 in GCP3) is largely responsible for GCP3 being able to hydrolyze β-citrylglutamate. Based on the crystal structure of GCP3 and kinetic analysis, we propose that GCP3 forms a labile catalytic Zn-Ca cluster that is critical for its β-citrylglutamate hydrolase activity. PMID:21908619

  14. High levels of γ-glutamyl hydrolase (GGH) are associated with poor prognosis and unfavorable clinical outcomes in invasive breast cancer

    Previously, we performed analysis of gene expression in 46 axillary lymph node negative tumors and identified molecular gene signatures that resulted in different clinical outcomes. The aim of this study was to determine the correlation of γ-glutamyl hydrolase (GGH), fatty acid amide hydrolase (FAAH), Pirin (PIR) and TAF5-like RNA polymerase II, p300/CBP-associated factor (PCAF)-associated factor, 65 kDa (TAF5L), selected from identified gene signatures, with clinical outcomes as well as classical clinicopathological characteristics in primary invasive breast cancer patients. The protein levels of GGH, FAAH, PIR and TAF5L were assessed by immunohistochemistry (IHC) on a panel of 80 primary invasive breast tumors. Quantitative real-time PCR (qRT-PCR) and western blot analysis were performed to verify the expression levels of the candidate biomarkers. Patient disease-specific survival (DSS) and recurrence-free survival (RFS) were evaluated using the Kaplan-Meier method. The prognostic biomarkers were identified by univariate analysis with a log-rank test and by multivariate analysis with Cox proportional hazards regression models. The GGH and FAAH protein levels were significantly up-regulated in invasive breast cancer tumors compared with adjacent non-cancerous tissues. Furthermore, the protein levels of GGH and FAAH were significantly correlated in tumor tissues. Tumoral GGH protein expression was significantly correlated with shorter DSS and RFS. Furthermore, the protein expression of GGH was positively correlated with undifferentiated tumors (BRE grade III) and ER/PR expressing tumors. Multivariate regression analysis showed that only GGH protein expression independently predicts DSS. No such correlations were found for FAAH, PIR and TAF5L protein expression. However, elevated protein levels of FAAH were positively associated with high number of lymph node involvement and upregulated levels of PIR were positively related with lymph node metastasis. The TAF5L was

  15. Synthesis of amide derivatives of 6{alpha},7{beta}-di-hydroxyvouacapan-17{beta}-oic acid isolated from the Pterodon polygalaeflorus Benth fruits (leguminosae); Sintese de amidas derivadas do acido 6{alpha},7{beta}-di-hidroxivouacapan-17{beta}-oico isolado dos frutos de Pterodon polygalaeflorus Benth (leguminosae)

    Teixeira, A.L.; Belinelo, V.J.; Stefani, G.M.; Pilo-Veloso, D. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica]. E-mail: dorila@dedalus.lcc.ufmg.br; Reis, G.T. [Universidade de Itauna, MG (Brazil). Dept. de Ciencias; Ferreira-Alves, D.L. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Farmacologia

    2001-04-01

    Hydro-alcoholic infusions from fruits of Pterodon polygalaeflorus Benth, commonly known as 'Sucupira branca', are used in Brazilian folk medicine for rheumatic problems and throat infections. Since it has been verified that furanediterpene 6?,7?-di-hydroxyvouacapan-17?-oic acid (ADV), isolated from the hexane extract of these fruits presents anti-inflammatory, analgesic, and plant growth regulatory activity, a variety of ADV derivatives has been synthesized with the aim of obtaining more information about the structure-activity relationships of this series of compounds. In this work four new amide (4-7) derivatives of ADV have been synthesized. Their structures were established by spectroscopic data, including 2D-NMR methods. (author)

  16. Structural analysis of Clostridium acetobutylicum ATCC 824 glycoside hydrolase from CAZy family GH105

    Germane, Katherine L., E-mail: katherine.germane.civ@mail.mil [Oak Ridge Associated Universities, 4692 Millennium Drive, Suite 101, Belcamp, MD 21017 (United States); Servinsky, Matthew D. [US Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783 (United States); Gerlach, Elliot S. [Federal Staffing Resources, 2200 Somerville Road, Annapolis, MD 21401 (United States); Sund, Christian J. [US Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD 20783 (United States); Hurley, Margaret M., E-mail: katherine.germane.civ@mail.mil [US Army Research Laboratory, 4600 Deer Creek Loop, Aberdeen Proving Ground, MD 21005 (United States); Oak Ridge Associated Universities, 4692 Millennium Drive, Suite 101, Belcamp, MD 21017 (United States)

    2015-07-29

    The crystal structure of the protein product of the C. acetobutylicum ATCC 824 gene CA-C0359 is structurally similar to YteR, an unsaturated rhamnogalacturonyl hydrolase from B. subtilis strain 168. Substrate modeling and electrostatic studies of the active site of the structure of CA-C0359 suggests that the protein can now be considered to be part of CAZy glycoside hydrolase family 105. Clostridium acetobutylicum ATCC 824 gene CA-C0359 encodes a putative unsaturated rhamnogalacturonyl hydrolase (URH) with distant amino-acid sequence homology to YteR of Bacillus subtilis strain 168. YteR, like other URHs, has core structural homology to unsaturated glucuronyl hydrolases, but hydrolyzes the unsaturated disaccharide derivative of rhamnogalacturonan I. The crystal structure of the recombinant CA-C0359 protein was solved to 1.6 Å resolution by molecular replacement using the phase information of the previously reported structure of YteR (PDB entry (http://scripts.iucr.org/cgi-bin/cr.cgi?rm)) from Bacillus subtilis strain 168. The YteR-like protein is a six-α-hairpin barrel with two β-sheet strands and a small helix overlaying the end of the hairpins next to the active site. The protein has low primary protein sequence identity to YteR but is structurally similar. The two tertiary structures align with a root-mean-square deviation of 1.4 Å and contain a highly conserved active pocket. There is a conserved aspartic acid residue in both structures, which has been shown to be important for hydration of the C=C bond during the release of unsaturated galacturonic acid by YteR. A surface electrostatic potential comparison of CA-C0359 and proteins from CAZy families GH88 and GH105 reveals the make-up of the active site to be a combination of the unsaturated rhamnogalacturonyl hydrolase and the unsaturated glucuronyl hydrolase from Bacillus subtilis strain 168. Structural and electrostatic comparisons suggests that the protein may have a slightly different substrate

  17. X-Ray Diffraction Structure of a plant Glycosyl Hydrolase family 32 protein: Fructan 1-Exohydrolase IIa of Cichorium intybus

    Verhaest, Maureen; Van den Ende, Wim; Le Roy, Katrien; De Ranter, Camiel; Van Laere, André; Rabijns, Anja

    2005-01-01

    Fructan 1-exohydrolase, an enzyme involved in fructan degradation, belongs to the glycosyl hydrolase family 32. The structure of isoenzyme 1-FEH IIa from Cichorium intybus is described at a resolution of 2.35 Å. The structure consists of an N-terminal fivefold β-propeller domain connected to two C-terminal β-sheets. The putative active site is located entirely in the β-propeller domain and is formed by amino acids which are highly conserved within glycosyl hydrolase family 32. The fructan-bin...

  18. Crystal structure of bile salt hydrolase from Lactobacillus salivarius.

    Xu, Fuzhou; Guo, Fangfang; Hu, Xiao Jian; Lin, Jun

    2016-05-01

    Bile salt hydrolase (BSH) is a gut-bacterial enzyme that negatively influences host fat digestion and energy harvesting. The BSH enzyme activity functions as a gateway reaction in the small intestine by the deconjugation of glycine-conjugated or taurine-conjugated bile acids. Extensive gut-microbiota studies have suggested that BSH is a key mechanistic microbiome target for the development of novel non-antibiotic food additives to improve animal feed production and for the design of new measures to control obesity in humans. However, research on BSH is still in its infancy, particularly in terms of the structural basis of BSH function, which has hampered the development of BSH-based strategies for improving human and animal health. As an initial step towards the structure-function analysis of BSH, C-terminally His-tagged BSH from Lactobacillus salivarius NRRL B-30514 was crystallized in this study. The 1.90 Å resolution crystal structure of L. salivarius BSH was determined by molecular replacement using the structure of Clostridium perfringens BSH as a starting model. It revealed this BSH to be a member of the N-terminal nucleophile hydrolase superfamily. Crystals of apo BSH belonged to space group P21212, with unit-cell parameters a = 90.79, b = 87.35, c = 86.76 Å (PDB entry 5hke). Two BSH molecules packed perfectly as a dimer in one asymmetric unit. Comparative structural analysis of L. salivarius BSH also identified potential residues that contribute to catalysis and substrate specificity. PMID:27139829

  19. Characterization of intracellular pteroylpolyglutamate hydrolase (PPH) from human intestinal mucosa

    Wang, T.T.Y.; Chandler, C.J.; Halsted, C.H.

    1986-03-01

    There are two forms of pteroylpolyglutamate hydrolase (PPH) in the human intestinal mucosa, one in the brush border membrane and the other intracellular; brush border PPH is an exopeptidase with optimal activity at pH 6.5 and a requirement for zinc. The presence study characterized human intracellular PPH and compared its properties to those of brush border PPH. Intracellular PPH was purified 30-fold. The enzyme had a MW of 75,000 by gel filtration, was optimally active at pH 4.5, and had an isoelectric point at pH 8.0. In contrast to brush border PPH, intracellular PPH was unstable at increasing temperatures, was unaffected by dialysis against chelating agents and showed no requirement for Zn/sup 2 +/. Using PteGlu/sub 2/(/sup 14/C)Glu as substrate, they demonstrated a K/sub m/ of 1.2 ..mu..M and increasing affinity for folates with longer glutamate chains. Intracellular PPH required the complete folic acid (PteGlu) moiety and a ..gamma..-glutamyl linkage for activity. Using ion exchange chromatography and an HPLC method to determine the hydrolytic products of the reaction, they found intracellular PPH could cleave both internal and terminal ..gamma..-glutamyl linkages, with PteGlu as an end product. After subcellular fractionation of the mucosa, PPH was found in the lysosomes. In summary, the distinct characteristics of brush border and intracellular PPH suggest that the two hydrolases serve different roles in folate metabolism.

  20. Convergent synthesis of digitally-encoded poly(alkoxyamine amide)s.

    Roy, Raj Kumar; Laure, Chloé; Fischer-Krauser, Diane; Charles, Laurence; Lutz, Jean-François

    2015-11-01

    Binary-encoded poly(alkoxyamine amide)s were prepared by oligomer ligation. These polymers contain digital sequences based on two monomers defined as 0 and 1 bits. A library of oligomers containing all possible dyads 00, 01, 10 and 11 was prepared and used to construct long coded sequences. PMID:26359908

  1. Aspergillus niger DLFCC-90 Rhamnoside Hydrolase, a New Type of Flavonoid Glycoside Hydrolase

    Liu, Tingqiang; Yu, Hongshan; Zhang, Chunzhi; Lu, Mingchun; Piao, Yongzhe; Ohba, Masashi; Tang, Minqian; Yuan, Xiaodong; Wei, Shenghua; Wang, Kan; Ma, Anzhou; Feng, Xue; Qin, Siqing; Mukai, Chisato; Tsuji, Akira

    2012-01-01

    A novel rutin-α-l-rhamnosidase hydrolyzing α-l-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the α-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13.

  2. Hydrolase activity in Jerusalem artichoke and chicory

    Klaushofer, H.; Abraham, B.; Leichtfried, G.

    1988-03-01

    Post-harvest storage of chicory and Jerusalem artichoke and overwintering of Jerusalem artichoke in the soil cause a more or less pronounced shortening of the fructan chain, depending on the variety. The proportion of fructose in the total fructan thus shifts towards glucose. This reduction on the fructose/glucose ratio is undesirable if the intention is to obtain a sweetener of high fructose content. In this work an attempt was made, via the quantity of fructose formed after a 4(3)-hour reaction of a tuber (root) extract with inulin, to assign a characteristic value to the depolymerization tendency of the material in question. However, since the plant extract not only contains enzymes (hydrolase A and B) that shorten the fructan chains but the activity of fructosyltransferase (SST, FFT) and enzymes of microbial origin (inulinase II, invertase) must also be considered, the concept of 'hydrolase activity' used by the authors is essentially an expression of 'total activity'. The activity unit (EU) is defined as the ability to split of 1 ..mu..mol of fructose from (chicory) inulin per minute under experimental conditions. Values of 0.25 to 0.77 EU/g dry solids were found in Jerusalem artichoke. Considerable differences may occur between varieties from the same cultivated area and the same harvest period. With one and the same variety, the activity appears to be subject to marked yearly fluctuations, so that at present, because of hydrolase activity, nothing certain can be said about the depolymerization tendency of a variety.

  3. A Two-Dimensional Zinc Coordination Polymer Based on a Pyridyl-Carboxylate Linking Ligand Containing an Intervening Amide Group: [ZnCl(L)]∞ (HL = 6-(nicotinamido)-2-naphthoic acid)

    According to the very recent IUPAC recommendations for the terminology, CPs are coordination compounds with repeating coordination entities extending in 1, 2, or 3 dimensions, and MOFs are coordination networks with organic ligands containing potential voids. IUPAC also recommended the use of the term 'coordination networks' to indicate coordination compounds extending, through repeating coordination entities, in 1 dimension, but with cross-links between two or more individual chains, loops, or spiro-links, or coordination compounds extending through repeating coordination entities in 2 or 3 dimensions. For the successful preparation of such polymeric species, the choice or design of proper linking ligands is essential, and those possessing either pyridyl or carboxylate terminals are typically employed. In particular, we became interested in the pyridyl.carboxylate-type ligands containing an amide (-C(O)-NH-) fragment, which might be utilized further for the so-called post-synthetic modification of CPs and MOFs. In this context, our group recently prepared two ligands of this type (HL and HL' in Chart 1), both of which contain a 3-pyridyl and a carboxylate terminals

  4. Production of R-(-)-Ketoprofen from an Amide Compound by Comamonas acidovorans KPO-2771-4

    Yamamoto, K; Otsubo, K; Matsuo, A.; T Hayashi; Fujimatsu, I; Komatsu, K.

    1996-01-01

    R-(-)-2-(3(prm1)-Benzoylphenyl)propionic acid [R-(-)-ketoprofen] was produced from racemic 2-(3(prm1)-benzoylphenyl)propionamide (keto-amide) by the isolated bacterial strain Comamonas acidovorans KPO-2771-4. Sodium fumarate as the carbon source and 2-azacyclononanone or isobutyronitrile as the enhancer in the culture medium were effective for bacterial growth and the enhancement of R-(-)-ketoprofen-producing activity. R-(-)-Ketoprofen produced from the keto-amide by resting cells was present...

  5. Tuning the thermoresponsive properties of Hyperbranched Poly(ester amide)s based on diisopropanolamine and cyclic dicarboxylic anhydrides

    Kelland, Malcolm

    2011-01-01

    A range of water-soluble hyperbranched poly(ester amide)s has been synthesized with a view to studying their thermoresponsive behavior in water. Poly(ester amide)s with lower critical solution temperature (LCST) values around physiological temperatures are of interest for biological and medical applications, whereas poly(ester amide)s with high LCST values may be useful as kinetic hydrate inhibitors for high salinity produced fluids in the oil and gas industry. The LCST of these p...

  6. The design, synthesis of amide KARI inhibitors and their biological activities

    Baolei WANG; Yi MA; Yonghong LI; Suhua WANG; Zhengming LI

    2009-01-01

    Ketol-acid reductoisomerase(KARI) is a promising target for the design of herbicides yet there are only few reports on the molecular design of KARI inhibitors. In this paper, based on the reported 0.165 nm high resolution crystal structure of the spinach KARI complex, 279 molecules with low binding energy toward KARI were obtained from an MDL/ACD 3D database search using the program DOCK 4.0. According to the structural information of 279 molecules provided, some amide compounds have been designed and synthesized. The bioassay results show that most of these amides had inhibitory activity to rice KARI at a test concentration of 200 μg/mL. Among which eight amides, compounds 1 and 6 show 57.4% and 48.1% inhibitory activity to KARI. The herbicidal activities of these amides were further investigated on di-cotyledonous rape (Brassica campestris) and mono-cotyledonous bar-nyardgrass (Echinochloa crusgalli). Compounds 1 and 6 were more favorable than others and showed 52.0% and 72.6% inhibitory activity on rape root at 100 μg/mL concentration, respectively. These amides could be further optimized for finding more potent candidates.

  7. Discovery of enantioselectivity of urea inhibitors of soluble epoxide hydrolase.

    Manickam, Manoj; Pillaiyar, Thanigaimalai; Boggu, PullaReddy; Venkateswararao, Eeda; Jalani, Hitesh B; Kim, Nam-Doo; Lee, Seul Ki; Jeon, Jang Su; Kim, Sang Kyum; Jung, Sang-Hun

    2016-07-19

    Soluble epoxide hydrolase (sEH) hydrolyzes epoxyeicosatrienoic acids (EETs) in the metabolic pathway of arachidonic acid and has been considered as an important therapeutic target for chronic diseases such as hypertension, diabetes and inflammation. Although many urea derivatives are known as sEH inhibitors, the enantioselectivity of the inhibitors is not highlighted in spite of the stereoselective hydrolysis of EETs by sEH. In an effort to explore the importance of enantioselectivity in the urea scaffold, a series of enantiomers with the stereocenter adjacent to the urea nitrogen atom were prepared. The selectivity of enantiomers of 1-(α-alkyl-α-phenylmethyl)-3-(3-phenylpropyl)ureas showed wide range differences up to 125 fold with the low IC50 value up to 13 nM. The S-configuration with planar phenyl and small alkyl groups at α-position is crucial for the activity and selectivity. However, restriction of the free rotation of two α-groups with indan-1-yl or 1,2,3,4-tetrahydronaphthalen-1-yl moiety abolishes the selectivity between the enantiomers, despite the increase in activity up to 13 nM. The hydrophilic group like sulfonamido group at para position of 3-phenylpropyl motif of 1-(α-alkyl-α-phenylmethyl-3-(3-phenylpropyl)urea improves the activity as well as enantiomeric selectivity. All these ureas are proved to be specific inhibitor of sEH without inhibition against mEH. PMID:27092411

  8. Epoxide hydrolase of Trichoderma reesei: Biochemical properties and conformational characterization.

    de Oliveira, Gabriel Stephani; Adriani, Patricia Pereira; Borges, Flavia Garcia; Lopes, Adriana Rios; Campana, Patricia T; Chambergo, Felipe S

    2016-08-01

    Epoxide hydrolases (EHs) are enzymes that are present in all living organisms and catalyze the hydrolysis of epoxides to the corresponding vicinal diols. EHs have biotechnological potential in chiral chemistry. We report the cloning, purification, enzymatic activity, and conformational analysis of the TrEH gene from Trichoderma reesei strain QM9414 using circular dichroism spectroscopy. The EH gene has an open reading frame encoding a protein of 343 amino acid residues, resulting in a molecular mass of 38.2kDa. The enzyme presents an optimum pH of 7.2, and it is highly active at temperatures ranging from 23 to 50°C and thermally inactivated at 70°C (t1/2=7.4min). The Michaelis constants (Km) were 4.6mM for racemic substrate, 21.7mM for (R)-(+)-styrene oxide and 3.0mM for (S)-(-)-styrene oxide. The kcat/Km analysis indicated that TrEH is enantioselective and preferentially hydrolyzes (S)-(-)-styrene oxide. The conformational stability studies suggested that, despite the extreme conditions (high temperatures and extremely acid and basic pHs), TrEH is able to maintain a considerable part of its regular structures, including the preservation of the native cores in some cases. The recombinant protein showed enantioselectivity that was distinct from other fungus EHs, making this protein a potential biotechnological tool. PMID:27177457

  9. Disrupting Dimerization Translocates Soluble Epoxide Hydrolase to Peroxisomes.

    Jonathan W Nelson

    Full Text Available The epoxyeicosatrienoic acid (EET neutralizing enzyme soluble epoxide hydrolase (sEH is a neuronal enzyme, which has been localized in both the cytosol and peroxisomes. The molecular basis for its dual localization remains unclear as sEH contains a functional peroxisomal targeting sequence (PTS. Recently, a missense polymorphism was identified in human sEH (R287Q that enhances its peroxisomal localization. This same polymorphism has also been shown to generate weaker sEH homo-dimers. Taken together, these observations suggest that dimerization may mask the sEH PTS and prevent peroxisome translocation. In the current study, we test the hypothesis that dimerization is a key regulator of sEH subcellular localization. Specifically, we altered the dimerization state of sEH by introducing substitutions in amino acids responsible for the dimer-stabilizing salt-bridge. Green Fluorescent Protein (GFP fusions of each of mutants were co-transfected into mouse primary cultured cortical neurons together with a PTS-linked red fluorescent protein to constitutively label peroxisomes. Labeled neurons were analyzed using confocal microscopy and co-localization of sEH with peroxisomes was quantified using Pearson's correlation coefficient. We find that dimer-competent sEH constructs preferentially localize to the cytosol, whereas constructs with weakened or disrupted dimerization were preferentially targeted to peroxisomes. We conclude that the sEH dimerization status is a key regulator of its peroxisomal localization.

  10. Direct Lactamization of Azido Amides via Staudinger-Type Reductive Cyclization

    Heo, In Jung; Lee, Su Jeong; Cho, Chang Woo [Kyungpook National University, Daegu (Korea, Republic of)

    2012-01-15

    The direct lactamization of 1,3- and 1,4-azido amides has been achieved using triphenylphosphine and water, affording various γ- and δ-lactams in good to excellent yields. The direct lactamization of the azido amides was performed via the Staudinger-type reductive cyclization in which the amide group acts as the electrophile for lactam synthesis. This lactamization provides a mild, functional group tolerant and efficient route for the synthesis of various γ- and δ-lactams found in natural products and pharmaceuticals. Further studies will be conducted to develop new synthetic routes for the synthesis of various lactams. The lactam ring system is one of the most ubiquitous structural motifs found in natural products and pharmaceuticals. Owing to the prevalence of lactams, their synthesis has attracted considerable attention. Lactams are usually prepared by the coupling of activated carboxylic acid derivatives with amines. Alternative routes include the Beckmann rearrangement of oximes, the Schmidt reaction of cyclic ketones and hydrazoic acid, the Kinugasa reaction of nitrones and terminal acetylenes, the Diels-Alder reaction of cyclopentadiene and chlorosulfonyl isocyanate, transition metal catalyzed lactamization of amino alcohols, and iodolactamization of amides and alkenes. In particular, the intramolecular Staudinger ligation of azides and activated carboxy acids, including esters, is well known as an environmentally friendly and mild protocol for lactam synthesis.