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DMDP acetic acid [N-carboxymethyl-2,5-dideoxy-2,5-imino-d-mannitol] 5 from Stevia rebaudiana is the first isolated natural amino acid derived from iminosugars bearing an N-alkyl acid side chain; it is clear from GCMS studies that such derivatives with acetic and propionic acids are common in a broad range of plants including mulberry, Baphia, and English bluebells, but that they are very difficult to purify. Reaction of unprotected pyrrolidine iminosugars with aqueous glyoxal gives the corresponding N-acetic acids in very high yield; Michael addition of both pyrrolidine and piperidine iminosugars and that of polyhydroxylated prolines to tert-butyl acrylate give the corresponding N-propionic acids in which the amino group of β-alanine is incorporated into the heterocyclic ring. These easy syntheses allow the identification of this new class of amino acid in plant extracts and provide pure samples for biological evaluation. DMDP N-acetic and propionic acids are potent α-galactosidase inhibitors in contrast to potent β-galactosidase inhibition by DMDP. [ABSTRACT FROM AUTHOR]

In order to emphasize the importance of electrolyte-tuning in the nitroxyl radicals mediated electrocatalytic reactions, methanol and glycine electrooxidation reactions catalyzed by TEMPO under different properties (pH, identity, concentration) of buffer solutions were investigated by cyclic voltammetry. It was discovered that in both carbonate buffer solutions and borate buffer solutions, catalytic abilities increase with the rising of pH for both glycine electrooxidation and methanol electrooxidation. The electrocatalytic performance is also affected by the identity of buffer, for both cases of glycine and methanol, the electrooxidation activities in borate buffer solutions are apparently higher than those in carbonate buffer solutions. For both glycine and methanol electrooxidation, relationships between concentrations of carbonate ions and relative catalytic current densities were observed to be volcano-shaped, while electrocatalytic abilities increase with the increasing of concentrations of borate ions within the studied concentration range. These findings suggest that the electrolyte should be treated as important as the catalyst in the designing of nitroxyl radicals mediated electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Background Several acylcarnitines used as primary markers on dried blood filter papers (DBS) for newborn screening lack specificity and contribute to a higher false positive rate. The analysis of urine acylglycines is useful in the diagnosis of inborn errors of metabolism (IEM) including medium chain acyl-CoA dehydrogenase deficiency (MCADD), isovaleric acidemia, and beta-ketothiolase deficiency (BKTD). Currently, no method for analyzing acylglycines from DBS has been published. Methods Acylglycines were extracted from two 3.2 mm DBS punches and butylated using Butanol-HCl. Ultra Performance Liquid Chromatography (UPLC-MS/MS) with run time of 10 min permits resolution and quantitation of 15 acylglycines; including several isobaric. Method development was completed. Reference intervals (n = 573) were established for four birth weight groups. Furthermore, samples from patients with a confirmed IEM (n = 11), and false positive screens (n = 78) were analyzed to validate the interpretation obtained from the newly established reference intervals. Results Calibration curves were linear from 0.005 to 25.0 μM. Ion suppression was evaluated as minimal (2 to 10%). Samples from known patients were used to validate the reference intervals. For C5OH-related disorders, tiglylglycine (TG), TG/acetylglycine (AG) ratio, 3methylcrotonylglycine (3MCG) and 3MCG/AG ratio increased specificity. Propionylglycine (PG) and PG/acetylglycine ratio were two discriminatory markers in the investigation of C3-related disorders. Hexanoylglycine (HG), octanoylglycine (OG), suberylglycine (SG), and the ratios HG/AG, OC/AG and SG/AG were excellent markers of MCADD deficiency. Conclusion This method shows potential application as a second tier screen in order to reduce the false positive rate for a number of IEM targeted by newborn screening. [ABSTRACT FROM AUTHOR]

Isotopic labeling strategies are coupled with solid-state NMR spectroscopy to characterize elastin's abundant glycines (Gly) and prolines (Pro) and the sequences that include these residues. Elastin is prepared with isotopic labels at Gly, Pro, and Val--three of its four most abundant amino acids. Solid-state 15N-¹H nuclear magnetic resonance (NMR) spectra show four resolved glycine populations, whereas three features are observed for the prolines. Selection of the Val-Pro and Gly-Gly pairs found exclusively and abundantly in the hydrophobic domains confirms these assignments and also provides more information on the conformational ensembles of elastin. The ¹HN and 15N temperature coefficients indicate that discrete secondary structures are present, even among significant populations with rapid conformational fluctuations typical of a random coil. 13C-15N couplings and the 13C chemical shift anisotropy (CSA) are also utilized to confirm assignments and structure, respectively. Implications for the evolving conformational ensemble model for elastin are also discussed. [ABSTRACT FROM AUTHOR]

The cysteine- and glycine-rich protein (CRP) family members, including the cysteine- and glycine-rich protein 1 ( CSRP1 ), cysteine- and glycine-rich protein 2 ( CSRP2 ), and the cysteine- and glycine-rich protein 3 ( CSRP3 ), have exhibited various cellular functions during cell development and differentiation. However, the sequences of the three CSRP genes and their functions are still poorly understood in newts. In this study, we cloned the complete open reading frame (ORF) sequences of the three CSRP genes from the Chinese fire-bellied newt, Cynops orientalis (C. orientalis) . The complete ORF sequences of Co-CSRP1 , Co-CSRP2 , and Co-CSRP3 were 582, 582, and 576 bp, respectively, and encoded 193, 193, and 191 amino acids, respectively. The deduced amino acid sequences of the three CRP members showed high similarities with that of other species, particularly, with amphibians. Co-CSRP1 was highly expressed in the kidney, limb, and stomach, however, the expression was low in the spleen, heart, intestine, liver, and tail ( P < 0.05). The mRNA expression of Co-CSRP2 was higher in the kidney and heart than that in other organs ( P < 0.05). It was observed that Co-CSRP3 was only expressed in the heart, limb, and tail. The mRNA expression of Co-CSRP1 and Co-CSRP3 was lower in the digits in comparison to other limb segments. However, there was no significant difference of Co-CSRP2 mRNA expression in the four limb segments. The Co-CSRP1 and Co-CSRP2 mRNA expressions were significantly increased, whereas the expression of Co-CSRP3 was remarkably decreased during the limb regeneration. This study will provide useful information for further elucidating the role of Co-CSRP genes during newt limb regeneration. [ABSTRACT FROM AUTHOR]

In a recent computational study, we found that hydrogen bonding/partial deprotonation facilitates subsequent electron transfer from amides to HO•. We have now analyzed these and related reactions with a glycine derivative as a model peptide, investigating not only reaction energies but also barriers for the individual steps. We find that partial deprotonation not only assists subsequent electron transfer (a sequential proton-loss electron-transfer (SPLET)-type reaction pathway) but also promotes sequential hydrogen-atom transfer (HAT, in a sequential proton-loss hydrogen-atom-transfer (SPLHAT)-type process), both being potential alternatives to direct HAT as routes for peptide oxidation. Each of these alternative pathways is calculated to have energy requirements that make them accessible and competitive. These oxidative processes may produce α-carbon-centered peptide radicals that, through deprotonation, are readily oxidized to the corresponding imines. We have also examined the possibility of competing reactions of amino acid side chains by comparing reactions of the glycine model with those of an analogous valine derivative. We find that, while the side chains of amino acids are more reactive toward direct HAT, a preceding partial deprotonation instead continues to favor the SPLET- and SPLHAT-type reactions, leading to the production of α-carbon-centered peptide radicals. Taken together, these processes have broad implications that impact many aspects of the science and utility of peptides. [ABSTRACT FROM AUTHOR]

Imino derivatives of glycine ester were prepared from methyl glycinate by the known procedure and then they reacted with several amines under microwave irradiation without solvent that gave the corresponding glycine amides. By the one-component cyclocondensation, the obtained amide derivatives were transformed into thiohydantoin-type imidazolinones using solvent-free microwave procedure. All imine-ester derivatives and most of the imidazolinone derivatives were synthesized for the first time. This eco-friendly protocol can provide a suitable way for synthesizing new potentially bioactive imidazolinone derivatives. [ABSTRACT FROM AUTHOR]

Corrosion is a severe challenge which restricts the use of mild steel (MS) in various application where it comes in contact with aggressive chemicals and conditions. In this regard, different inhibitors were chosen, but environment unfriendliness of such inhibitors is a primary cause of concern. In this study, we present the systematic investigation of an environmentally benign compound, a glycine derivative N-benzylidine-2((2-oxo-2-(10H-phenothiazine-10yl)ethyl)amino) acetohydrazide (BPAA), as potential corrosion inhibitor at different temperature (30, 40, 50, and 60 °C). The investigation is accomplished by using the techniques including electrochemical polarization, electrochemical impedance spectroscopy (EIS), gravimetric, UV-visible spectrophotometry, FT-IR spectroscopy. The morphological characterization of the samples has been done by using high resolution SEM. The evaluated compound works as effective inhibitor for acid corrosion at substantially lower concentration and its adsorption on the MS surface was found to followed the Langmuir adsorption isotherm. Calculated thermodynamic parameters for adsorption unveiled a strong interaction amongst the inhibitor-MS surface. The electrochemical results revealed that the inhibitor act as mixed-type. The corrosion inhibition efficiency (IE) of the inhibitor was synergistically enhanced in the presence of surfactant additives sodium dodecyl sulfate and cetyl pyridinium chloride at quite lower concentration and showed that the addition of surfactant is an alternate strategy to enhance the IE and reduce the cost. The order of IE acquired from experimental results is successfully verified by theoretical calculations. [ABSTRACT FROM PUBLISHER]

Abstract: To control supramolecular chirality of the co‐assembled nanostructures, one of the remaining issues is how stoichiometry of the different molecules involved in co‐assembly influence chiral transformation. Through co‐assembly of achiral 1,4‐bis(pyrid‐4‐yl)benzene and chiral phenylalanine‐glycine derivative hydrogelators, stoichiometry is found to be an effective tool for controlling supramolecular chirality inversion processes. This inversion is mainly mediated by a delicate balance between intermolecular hydrogen bonding interactions and π–π stacking of the two components, which may subtly change the stacking of the molecules, in turn, the self‐assembled nanostructures. This study exemplifies a simplistic way to invert the handedness of chiral nanostructures and provide fundamental understanding of the inherent principles of supramolecular chirality. [ABSTRACT FROM AUTHOR]

Cyanobacterial blooms have affected Lake Winnipeg since the mid-1990s due to an increased phosphorus loading into the lake, which has been exacerbated by stressors such as climate change and eutrophication. Aquatic ecosystems involving cyanobacteria have been found to contain N-β-methylamino-L-alanine (BMAA) and 2,4-diaminobutyric acid (DAB), non-protein amino acids that are associated with neurodegenerative disease, as well as two of the naturally occurring isomers, N-2(amino)ethylglycine (AEG) and β-amino- N-methylalanine (BAMA). We hypothesized that the cyanobacterial bloom in Lake Winnipeg produces BMAA and/or its naturally occurring isomers. Samples of cyanobacteria were collected by the Lake Winnipeg Research Consortium from standard sampling stations and blooms in July and September of 2016 and were analyzed for BMAA, DAB, AEG, and BAMA using previously published validated analytical methods. BMAA and BAMA were found in the highest concentration in the center of the north basin, the deepest and lowest-nitrogen zone of the lake, at an average concentration of 4 μg/g (collected in July and September 2016) and 1.5 mg/g (collected in July 2016), respectively. AEG and DAB were found in the highest concentration in cyanobacterial blooms from the nearshore region of the north basin, the slightly shallower and more nitrogen-rich zone of the lake, at 2.1 mg/g (collected in July 2016) and 0.2 mg/g (collected in July and September 2016), respectively. These findings indicate that the production of non-protein amino acids varies with the depth and nutrient contents of the bloom. It is important to note that we did not measure food or water samples directly and further study of the Lake Winnipeg food web is required to determine whether BMAA bioaccumulation represents an increased risk factor for neurodegenerative disease in the region. [ABSTRACT FROM AUTHOR]

The non-protein amino acid (NPAA) ß-methylamino- l-alanine (BMAA) is produced by a diverse range of cyanobacteria, diatoms and dinoflagellates, and is present in both aquatic and terrestrial ecosystems globally. Exposure to BMAA has been implicated in the development of neurodegenerative diseases including amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD) and Parkinson's disease (PD). BMAA is often found in nature along with its structural isomers 2,4-diaminobutyric acid (2,4-DAB) and aminoethylglycine (AEG); however, the toxicity of these NPAAs in combination has not been examined. We have previously demonstrated that BMAA induces endoplasmic reticulum (ER) stress and increases caspase and cathepsin activity in human neuroblastoma cells (SH-SY5Y), effects consistent with proteotoxic stress due to disturbances in protein synthesis, folding or turnover. The current study investigates whether 2,4-DAB and AEG share a similar mechanism of toxicity to BMAA, and if simultaneous exposure of cells to BMAA and its isomers results in increased toxicity in vitro. We show that a 48-h treatment with both 500 μM BMAA and 2,4-DAB decreases cell viability in vitro whereas AEG was not cytotoxic under the same conditions . Treatment of SH-SY5Y cells with 2,4-DAB did not increase expression of ER stress markers. Combined treatment of cells with BMAA and 2,4-DAB resulted in increased caspase activity and increased apoptosis above that of BMAA or 2,4-DAB on their own. These results suggest that 2,4-DAB does not share the same mechanism of toxicity as BMAA but the presence of 2,4-DAB increases the toxicity of BMAA to human cells in vitro. [ABSTRACT FROM AUTHOR]

Photoinduced debenzylations of phenylalanine and tyrosine derivatives with dicyanoarenes afford glycine derivatives by the generation of radical cations. Despite the limited substrate scope, the radical cation of phenylalanine and tyrosine derivatives bearing both a carbamate (without an aromatic group) at the N -terminal and an amide at the C -terminal could promote the breaking C–C bond at the benzylic position by a photoinduced electron transfer. It is important to understand the chemical behavior of the radical cations of phenylalanine and tyrosine in enzymes involving electron transfer. [ABSTRACT FROM AUTHOR]

The effects of selenium and glycine (either separately or in combination) on hydrogen peroxide-induced cell death on U937 cells and activation of U937-derived macrophages were investigated. In the first instance, U937 cells were incubated with or without selenium (Se) or glycine (GLY) or both (Se + GLY) for 24 h before exposure to hydrogen peroxide. Control cells were not incubated with Se, GLY or exposed to hydrogen peroxide. Cell viability was later assessed via trypan blue and MTT assays. For the other experiment, U937 cells were transformed to the macrophage form using phorbol 12-myristate 13-acetate before incubating with or without Se, GLY, Se + GLY. Contents were subsequently exposed to hydrogen peroxide and 24 h later assessed for the production of TNF-α, IL-1, IL-6 and the expression of iNOS and NF-κB. The results revealed that hydrogen peroxide caused significant cell death which was ameliorated by both Se and GLY. Pre-incubation of the cells with both Se and GLY did not significantly enhance cell numbers compared to GLY ( p > 0.05). On the other hand, Se and GLY reduced hydrogen peroxide-mediated production of TNF-α, IL-1, IL-6 and expression of iNOS and NF-κB. Incubating the U937-derived macrophages with Se + GLY significantly ameliorated hydrogen peroxide-mediated activation of macrophages when compared to pre-treatments with Se or GLY ( p < 0.05). The findings demonstrate that both Se and GLY reduced hydrogen peroxide-induced alterations in U937 cells and U937-derived macrophages. Implications of the findings are discussed. [ABSTRACT FROM AUTHOR]

N -Acylglycines (NAGs), the endogenous single-tailed lipids present in rat brain and other mammalian tissues, play significant roles in cell physiology and exhibit interesting pharmacological properties. In the present study, a homologous series of N -acylglycine alkyl esters (NAGEs) with matched chains were synthesized and characterized. Results of differential scanning calorimetric studies revealed that all NAGEs exhibit a single sharp phase transition and that the transition enthalpy and entropy show a linear dependence on the N -acyl and ester alkyl chain length. The structure of N -myristoylglycine myristyl ester (NMGME), solved by single-crystal X-ray diffraction, showed that the molecule adopts a linear geometry and revealed that the structure of N- myristoyl glycyl moiety in NMGME is identical to that in N -myristoylglycine. The molecules are packed in layers with the polar functional groups of the ester and amide functionalities located at the center of the layer. The crystal packing is stabilized by N H⋯O hydrogen bonds between the amide C O and N H groups of adjacent molecules as well as by C H⋯O hydrogen bonds between the amide carbonyl and the methylene C H adjacent to the ester carbonyl of neighboring molecules as well as between ester carbonyl and methylene group of the glycine moiety of adjacent molecules. Powder X-ray diffraction studies showed a linear dependence of the d -spacings on the acyl chain length, suggesting that all NAGEs adopt a structure similar to the packing exhibited in the crystal lattice of NMGME. [ABSTRACT FROM AUTHOR]

The skyllamycins are a family of highly functionalized non-ribosomal cyclic depsipeptide natural products which contain the extremely rare α-OH-glycine functionality. Herein the first total synthesis of skyllamycins A-C is reported, together with the biofilm inhibitory activity of the natural products. Linear peptide precursors for each natural product were prepared through an efficient solid-phase route incorporating a number of synthetic modified amino acids. A novel macrocyclization step between a C-terminal amide and an N-terminal glyoxylamide moiety served as a key transformation to install the unique α-OH-glycine unit and generate the natural products in the final step of the synthesis. [ABSTRACT FROM AUTHOR]

The asymmetric α-sulfenylation of Ni( II) complex of glycine with S-substituted 4-methylbenzenesulfonothioate is reported. Due to the mild and simple reaction conditions, this asymmetric reaction is compatible with various functional groups. [ABSTRACT FROM AUTHOR]

Interest in lipoamino acids as endogenous modulators of G-protein coupled receptors has escalated due to their involvement in a variety of physiologic processes. In particular, a role for these amino acid conjugates has emerged in the endocannabinoid system. The study presented herein investigated the effects of N-arachidonoyl glycine (NAGly) on a candidate endocannabinoid receptor, GPR55. Our novel findings reveal that NAGly induces concentration dependent increases in calcium mobilization and mitogen-activated protein kinase activities in HAGPR55/CHO cells. These increases were attenuated by the selective GPR55 antagonist ML193 (N-[4-[[(3,4-Dimethyl-5-isoxazolyl)amino]sulfonyl]phenyl]-6,8-dimethyl-2-(2-pyridinyl)-4-quinolinecarboxamide), supporting receptor mediated signaling. To our knowledge this is the first report identifying GPR55 as a target of the endogenous lipoamino acid, NAGly. [ABSTRACT FROM AUTHOR]

Herein, we report the kinetic study of nickel-glycylglycine with ninhydrin in alkanediyl-α,ω-gemini (m = 16 and s = 4, 5, 6) surfactant system using UV–vis spectrophotometer. From the results, different rates, binding constants and thermodynamic parameters were evaluated. The critical micelle concentration (cmc) value of geminis with and without both the substrates (ninhydrin and nickel-glycylglycine) was determined by conductivity measurements. The reaction kinetics show first- and fractional-order dependencies on nickel-glycylglycine and ninhydrin, respectively. Effect of gemini surfactants on the title reaction was also seen and pointed out that they are superior over their corresponding conventional surfactant. The catalytic role of gemini surfactants has been discussed in detail. Quantitative analysis of kinetic data was explained by applying Menger-Portnoy model of the micelles. [ABSTRACT FROM AUTHOR]

Previously unknown substituted 4-aryl-2,7,9-triazaspiro[4.5]decane-6,8,10-triones were synthesized in 50-70% yield by heating 5-(arylmethylidene)barbituric acids with N-methyl- or N-phenylglycine and para-formaldehyde or 4-methoxybenzaldehyde in boiling toluene for 14 h. [ABSTRACT FROM AUTHOR]

Coumarin-oxazol-5-one (COX), 3a-d, were synthesized with 7-methoxy-2-oxo-2H-chromene-4-carbaldehyde and benzoylglycine derivatives. The characterizations of the COX derivatives by H NMR, FT-IR and elemental analysis were achieved. To obtain the photophysical data of the synthesized COX derivatives were used spectrophotometric and spectrofluorimetric methods. Evaluation of the absorption and emission properties of the structures was carried out in six different solvents. Maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm M), Stoke's shifts (Δλ nm) and quantum yields (ϕ), of the COX derivatives were declared. [ABSTRACT FROM AUTHOR]

Calcite growth rate has been previously shown to be the dominating parameter controlling both Mg partitioning and Mg isotope fractionation during calcite growth. In natural calcite precipitation environments - characterized by abundant organic material - the presence of dissolved organic molecules may affect these two parameters. In order to assess the role of organic molecules, steady state calcite growth experiments have been performed at 25 °C, 1 bar pCO 2 and constant, within analytical uncertainty growth rate ( r p = 10 −7.4 mol m −2 s −1 ) in the presence of aqueous Mg and six organic ligands in the concentration range from 0.01 to 10 mM. The organic ligands used in this study are: (i) acetic acid, (ii) citric acid, (iii) glutamic acid, (iv) salycilic acid, (v) glycine, and (vi) ethylenediaminetetraacetic acid (EDTA). These contain one or more carboxyl- and amino-groups that are commonly present in natural organic substances found in lacustrine, fluvial, soil, cave, as well as in marine and earliest diagenetic porewater environments. Results shown here indicate that the presence of these carboxyl- and amino-groups promotes an increase in the partition coefficient of Mg in calcite D Mg = ( Mg / Ca ) calcite ( Mg / Ca ) fluid that can be attributed to their adsorption onto the calcite surfaces and the subsequent reduction of the active sites of growth. This increase of D Mg values as a function of the supersaturation degree of calcite in the fluid phase can be described by the linear equation: Log D Mg = 0.3694 ( ± 0.0329 ) × SI calcite - 1.9066 ( ± 0.0147 ) R 2 = 0.92 In contrast, data shown here suggest that the presence of organic ligands, with exception of citric acid, does not significantly affect the Mg isotope fractionation factor between calcite and reactive fluid. Citric acid likely exhibits larger fractionation between the Mg-ligand complexes and free aqueous Mg, compared to the other organic ligands studied in this work, as evidenced from the smaller Δ 26 Mg calcite-fluid values. The main result shown here is that in Earth’s surface precipitation environments the presence of organic ligands is not a major factor affecting the Mg content or Mg-isotope composition of inorganic calcite. But in the presence of higher contents of organic macromolecules from byproducts of metabolic activities, humid, and fulvic acids and/or exopolymeric substances and matrices, an impact on Mg content or Mg isotope composition of calcite cannot be ruled out. [ABSTRACT FROM AUTHOR]

Controllable assembly of the hybrids composed of various types of nanoscale objects provides new opportunities for material fabrication. Herein, the tunable bi-functionalities of fluorescence and surface enhanced Raman scattering (SERS) signals were collected by the assembled composites of gold nanoparticles (AuNPs)/glycine derivatives (G n , n = 0, 3, 4, 5, 6 and 9)/graphene quantum dots (GQDs). The composition and structure of the AuNPs/G n /GQDs composites were characterized by Fourier-transform infrared (FT-IR) spectroscopy and high resolution transmission electron microscope (HRTEM). Results indicated that the fluorescence and SERS response could be tuned effectively by changing the chain length of G n . Also, the AuNPs/G n /GQDs composites could be used in a wide pH range and exhibited good stability at room and physiological temperatures. Moreover, the AuNPs/G n /GQDs composites displayed low cytotoxicity in A549 cells, and the cell viability was found to be above 90% at concentrations ranging from 6.42 to 200 μg/mL, which made AuNPs/G n /GQDs composites very attractive for biological imaging applications in vivo. [ABSTRACT FROM AUTHOR]

A novel reaction involving in situ redox conversion of glyoxylate esters to glycine is described. Simple starting materials and mild conditions for the synthesis of glycine derivatives probably indicate a pathway towards prebiotic chemistry. This proceeds analogous to Cannizzaro reaction involving ammonia therefore it can be termed as intramolecular Aza-Cannizzaro type reaction. This reaction is examined in detail with an aid of computational analysis to corroborate the proposed mechanism. [ABSTRACT FROM AUTHOR]

A gold-oxazoline complex-catalyzed dehydrogenative Povarov/oxidation tandem reaction for the synthesis of decorated quinolines has been developed from glycine derivatives and alkenes. The reaction performs under mild reaction conditions in the presence of oxygen as the oxidant and features a broad substrate scope and excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

We previously identified an N-terminal fragment of progastrin in human antrum and plasma, where it circulates in high concentrations. In this study, we examined the effects of N-terminal progastrin fragments on gastric acid secretion by infusion in healthy individuals. Increasing doses of progastrin fragment 1-35 were infused intravenously during constant gastric acid stimulation by gastrin-17. In addition, the effects of progastrin fragment 1-35, fragment 6-35, and fragment 1-19 on gastrin-17 stimulated acid secretion were tested. The gastrin-17 stimulated acid secretion decreased 30% after administration of a high dose of progastrin fragment 1-35 (P < 0.05). In extension, a 1-h infusion of fragment 1-35 also decreased gastric acid output. In contrast, fragment 6-35 did not affect acid secretion, and a single infusion of gastrin-17 alone did not reveal fading of gastric acid output during the time course of the experiments. The results show that N-terminal fragments of progastrin may acutely affect gastrin-stimulated gastric acid secretion in vivo. Structurefunction analysis suggests that the N-terminal pentapeptide of progastrin is required for the effect. [ABSTRACT FROM AUTHOR]

This newly designed route assembled a pyrazole ring with an aldehydic functionality over another pyrazole moiety. Further, formyl group was exploited in different routes such as condensation reactions, imidazole and pyrimidone/thione synthesis. The present reactions were performed with glycine, a facile catalyst, and the results were compared well with those of conventional methods. [ABSTRACT FROM AUTHOR]

The first diastereoselective synthesis of the 5-hydroxy-pyrrolidinone amino acid common to eight members of the microsclerodermin family is presented. Our strategy involves formal hydration of an unsaturated precursor via the use of a two-step hydroxybromination-debromination protocol; this procedure provides exclusively the requisite 4,5- cis -pyrrolidinone. Furthermore model studies are presented that indicated the potential viability of this hydration strategy in the context of a synthesis of microsclerodermin B. [ABSTRACT FROM AUTHOR]

Enantiomerically enriched coordination compounds of aspartic acid and racemic mixtures of coordination compounds of glycine metal-ligand ratio 1 : 3 were synthesized and characterized using infrared and UV-Vis spectrophotometric techniques and magnetic susceptibility measurements. Five of the complexes were resolved using (+)-cis-dichlorobis(ethylenediamine)cobalt(III) chloride, (+)-bis(glycinato)(1,10-phenanthroline)cobalt(III) chloride, and (+)-tris(1,10-phenanthroline)nickel(II) chloride as resolving agents. The antimicrobial and cytotoxic activities of these complexes were then determined. The results obtained indicated that aspartic acid and glycine coordinated in a bidentate fashion. The enantiomeric purity of the compounds was in the range of 22.10–32.10%, with (+)-cis-dichlorobis(ethylenediamine)cobalt(III) complex as the more efficient resolving agent. The resolved complexes exhibited better activity in some cases compared to the parent complexes for both biological activities. It was therefore inferred that although the increase in the lipophilicity of the complexes may assist in the permeability of the complexes through the cell membrane of the pathogens, the enantiomeric purity of the complexes is also of importance in their activity as antimicrobial and cytotoxic agents. [ABSTRACT FROM AUTHOR]

An article presents abstracts of several chemistry articles published in the periodical on topics including biosynthesis of the carbonylmethylene structure, structure of glycine dihydrate, and synthesis of optically pure helicene metallocenes.

Apparent molar properties ( V ∅ and K ∅ , s ) of amino acids (glycine, L -alanine and L -valine) within the concentration range of (0.02–0.20) mol·kg −1 in aqueous (0.005, 0.01 and 0.03) mol·kg −1 Levofloxacin (LVFX) solutions are computed from the experimental density ( ρ ) and ultrasonic speed ( c ) values at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K and P = 0.1 MPa. Derived parameters such as partial molar properties ( V ∅ 0 and K ∅ , s 0 ) and their experimental slopes ( S V and S K ) , transfer partial molar properties ( Δ V ∅ 0 and Δ K ∅ , s 0 ), hydration numbers ( n H ) and Hepler’s constant are computed from the data of apparent molar properties. The pair and triplet interaction coefficients have also been evaluated from transfer parameters. The linear variation of V ∅ 0 with the number of carbon atoms in the alkyl chain of amino acids has been utilized to calculate the contribution of the charged end groups ( NH 3 + , COO - ) , ( CH 2 ) group and other alkyl chains of the amino acids to V ∅ 0 . From the obtained parameters, some information in regard with the solute-solvent interaction in the systems studied was obtained. The co-sphere overlap model was used to interpret the positive transfer properties ( Δ V ∅ 0 and Δ K ∅ , s 0 ). The volume and compression data suggest that there exist strong solute-solvent interactions in these systems, which increase with increase in temperature. It is inferred that amino acids studied act as structure-breaker (chaotropic effect) in aqueous LVFX solutions. [ABSTRACT FROM AUTHOR]

The inhibition of gastric cyclooxygenase 1 (COX-1) enzyme was believed to be the major cause of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastric ulcer. Recent studies disproved this belief and showed that the gastric tissues vulnerability is not solely connected to COX-1 inhibition. This work aimed at exploring and rationalizing the differential analgesic and anti-inflammatory activities of novel selective COX-1 inhibitors with improved gastric profile. Two novel series of 4,5-diarylthiazole and diarylimidazole were designed, synthesized in analogy to selective COX-1 inhibitors (mofezolac and FR122047) which lack gastric damaging effects. The new compounds were evaluated in vitro for their COXs inhibitory activity and in vivo for their anti-inflammatory and analgesic potentials. Four compounds; diphenylthiazole glycine derivatives ( 15a , 15b ) and diphenylimidazolo acetic acid derivatives ( 19a , 19b ), which possess carboxylic acid group exhibited significant activity and selectivity against COX-1 over COX-2. Of these compounds, (4,5-bis(4-methoxyphenyl)thiazol-2-yl)glycine 15b was the most potent compound against COX-1 with an inhibitory half maximal concentration (IC 50 ) of 0.32 μM and a selectivity index (COX-2 IC 50 /COX-1 IC 50 ) of 28.84. Furthermore, an ulcerogenicity study was performed where the tested compounds demonstrated a significant gastric tolerance. Interestingly, the most selective COX-1 inhibitor showed higher analgesic activity in vivo as expected compared to their moderate anti-inflammatory activity. This study underscores the need for further design and development of novel analgesic agents with low tendency to cause gastric damage based on improving their COX-1 affinity and selectivity profile. [ABSTRACT FROM AUTHOR]

The solution chemistry of aluminum has long interested scientists due to its relevance to materials chemistry and geochemistry. The dynamic behavior of large aluminum-oxo-hydroxo clusters, specifically [Al13O4(OH)24(H2O)12]7+ ( Al13), is the focus of this paper. 27Al NMR, 1H NMR, and 1H DOSY techniques were used to follow the isomerization of the ϵ-Al13 in the presence of glycine and Ca2+ at 90 °C. Although the conversion of ϵ-Al13 to new clusters and/or Baker-Figgis-Keggin isomers has been studied previously, new 1H NMR and 1H DOSY analyses provided information about the role of glycine, the ligated intermediates, and the mechanism of isomerization. New 1H NMR data suggest that glycine plays a critical role in the isomerization. Surprisingly, glycine does not bind to Al30 clusters, which were previously proposed as an intermediate in the isomerization. Additionally, a highly symmetric tetrahedral signal ( δ=72 ppm) appeared during the isomerization process, which evidence suggests corresponds to the long-sought α-Al13 isomer in solution. [ABSTRACT FROM AUTHOR]

Amphiphiles and, in particular, PEGylated lipids or alkyl ethers represent an important class of non-ionic surfactants and have become key ingredients for long-circulating ("stealth") liposomes. While poly-(ethylene glycol) (PEG) can be considered the gold standard for stealth-like materials, it is known to be neither a bio-based nor biodegradable material. In contrast to PEG, polysarcosine (PSar) is based on the endogenous amino acid sarcosine (N-methylated glycine), but has also demonstrated stealth-like properties in vitro, as well as in vivo. In this respect, we report on the synthesis and characterization of polysarcosine based lipids with C14 and C18 hydrocarbon chains and their end group functionalization. Size exclusion chromatography (SEC) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis reveals that lipopeptoids with a degree of polymerization between 10 and 100, dispersity indices around 1.1, and the absence of detectable side products are directly accessible by nucleophilic ring opening polymerization (ROP). The values for the critical micelle concentration for these lipopolymers are between 27 and 1181 mg/L for the ones with C18 hydrocarbon chain or even higher for the C14 counterparts. The lipopolypeptoid based micelles have hydrodynamic diameters between 10 and 25 nm, in which the size scales with the length of the PSar block. In addition, C18PSar50 can be incorporated in 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) monolayers up to a polymer content of 3%. Cyclic compression and expansion of the monolayer showed no significant loss of polymer, indicating a stable monolayer. Therefore, lipopolypeptoids can not only be synthesized under living conditions, but my also provide a platform to substitute PEG-based lipopolymers as excipients and/or in lipid formulations. [ABSTRACT FROM AUTHOR]

Polyaspartic acid (PASP) is regarded as a kind of environmentally friendly and multifunctional polymer material, which possesses the property of biodegradation, chelation and dispersion. In this work, polyaspartic acid derivative such as GLY–PASP was synthesized and characterized by FTIR and 1 H NMR spectroscopic techniques. The performance of the synthesized polymer as corrosion inhibitor was evaluated by potentiodynamic polarization and EIS techniques. The performance as a scale inhibitor was tested by complexometric titration with standard solution of EDTA. Finally, SEM and EDX were used as surface analysis tools to study the surface morphology of carbon steel alloy in the absence and presence of the inhibitor molecules. The maximum corrosion inhibition efficiency for GLY-PASP adduct reaches for 83.8% at 250 ppm, while its scale inhibition efficiency reaches 90.2% at 125 ppm dosage. [ABSTRACT FROM AUTHOR]

A concise organocatalytic route toward the synthesis of furanose and pyranose substituted glycine and alanine derivatives is reported. These compounds are core structural units of some of the naturally available antibiotics and antifungal agents. Proline-catalyzed asymmetric α-amination of aldehydes derived from sugars is used as the key reaction to synthesize twelve sugar amino acid derivatives. The asymmetric transformations proceeded in good yields and with good to excellent diastereoselectivity. The application of the synthesized amino acids is demonstrated by synthesizing a tripeptide containing one of them. [ABSTRACT FROM AUTHOR]

A straightforward and transition-metal-free approach for the efficient synthesis of α-arylglycine derivatives from aromatic imines and carbon dioxide was enabled by an umpolung carboxylation reaction. Various substituted diphenylmethimines underwent the carboxylation smoothly with carbon dioxide in the presence of potassium tert-butoxide and 18-crown-6 to give the corresponding carboxylated products in good to high yields. Besides the enhancement of the solubility of potassium tert-butoxide in THF, 18-crown-6 also plays key roles in suppressing the reverse protonation or 1, 3-proton shift isomerization as well as by stabilizing the carboxylated intermediate. [ABSTRACT FROM AUTHOR]

A conformationally restricted monofluorinated α-amino acid, (3-fluorobicyclo[1.1.1]pentyl)glycine (F-Bpg), was designed as a label for the structural analysis of membrane-bound peptides by solid-state 19F NMR spectroscopy. The compound was synthesized and validated as a 19F label for replacing natural aliphatic α-amino acids. Calculations suggested that F-Bpg is similar to Leu/Ile in terms of size and lipophilicity. The 19F NMR label was incorporated into the membrane-active antimicrobial peptide PGLa and provided information on the structure of the peptide in a lipid bilayer. [ABSTRACT FROM AUTHOR]

This paper describes a nanocrystalline scandium oxide powder combustion synthesis and its sintering to transparent ceramics. The effect of the fuel type on the powder characteristics was investigated. Scandium acetate and acetylacetonate as well as glycine were chosen as a fuel. The obtained scandium oxide powders were characterized by powder X-ray diffraction, BET, scanning electron microscopy, and static light scattering. The best properties were observed for the powders prepared using glycine as a fuel. This product has a crystallite size of about 16 nm and a surface area of about 32 m 2 /g and could be deagglomerated under ultrasonication to submicron particles. The transparent scandium oxide ceramics was produced by vacuum microwave sintering of the glycine-derived powders with the ZrO 2 and Y 2 O 3 additives at 1750 °C for 3 h. [ABSTRACT FROM AUTHOR]

BACKGROUND Scandium (Sc) is an important metal element in high-technology industries and the demand for Sc has been increasing annually. However, because metallurgical processes for its purification and recovery are complex, an effective technique for its separation is required. This paper reports on the development of novel adsorbents that are capable of separating Sc efficiently. RESULTS Novel adsorbents were prepared by introducing aminocarbonylmethylglycine functional groups onto two types of support materials, silica gels for determining suitable preparation conditions and an organic resin for practical use. Scandium adsorption and separation were carried out in sulfuric media using these adsorbents. The adsorbents exhibited high selectivity to Sc from Mg, Al, Ca, Cr, Mn, Co and Ni except for Fe( III). Adsorption-desorption experiments were conducted to examine the adsorbent reusability. The adsorbents showed similar results in reuse tests without any obvious loss. CONCLUSIONS Aminocarbonylmethylglycine functional group introduction proved effective and efficient for Sc adsorption. The newly synthesized adsorbents showed high affinity for Sc and Fe( III). Sc was separated selectively from Fe by reducing Fe( III) to Fe( II) because the adsorbent showed no affinity for divalent Fe( II). The new resin based adsorbent can be used for the practical separation of Sc. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The mechanistic target of rapamycin complex 1 (mTORC1) coordinates cell growth with its nutritional, hormonal, energy, and stress status. Amino acids are critical regulators of mTORC1 that permit other inputs to mTORC1 activity. However, the roles of individual amino acids and their interactions in mTORC1 activation are not well understood. Here we demonstrate that activation of mTORC1 by amino acids includes two discrete and separable steps: priming and activation. Sensitizing mTORC1activation by priming amino acids is a prerequisite for subsequent stimulation of mTORC1 by activating amino acids. Priming is achieved by a group of amino acids that includes L-asparagine, L-glutamine, L-threonine, L-arginine, L-glycine, L-proline, L-serine, L-alanine, and L-glutamic acid. The group of activating amino acids is dominated by L-leucine but also includes L-methionine, L-isoleucine, and L-valine. L-Cysteine predominantly inhibits priming but not the activating step. Priming and activating steps differ in their requirements for amino acid concentration and duration of treatment. Priming and activating amino acids use mechanisms that are distinct both from each other and from growth factor signaling. Neither step requires intact tuberous sclerosis complex of proteins to activate mTORC1. Concerted action of priming and activating amino acids is required to localize mTORC1 to lysosomes and achieve its activation. [ABSTRACT FROM AUTHOR]

We present a laboratory reproduction of hypervelocity impacts of a carbon containing meteorite on a mineral substance representative of planetary surfaces. The physical conditions of the resulting impact plasma torch provide favorable conditions for abiogenic synthesis of protein amino acids: We identified glycine and alanine, and in smaller quantities serine, in the produced material. Moreover, we observe breaking of alanine mirror symmetry with L excess, which coincides with the bioorganic world. Therefore the selection of L-amino acids for the formation of proteins for living matter could have been the result from plasma processes occurring during the impact meteorites on the surface. This indicates that the plasma torch from meteorite impacts could play an important role in the formation of biomolecular homochirality. Thus, meteorite impacts possibly were the initial stage of this process and promoted conditions for the emergence of a living matter. [ABSTRACT FROM AUTHOR]

We have developed a novel, rapid and easy calculation procedure for Mass Isotopomer Distribution Analysis based on multiple linear regression which allows the simultaneous calculation of the precursor pool enrichment and the fraction of newly synthesized labelled proteins (fractional synthesis) using linear algebra. To test this approach, we used the peptide RGGGLK as a model tryptic peptide containing three subunits of glycine. We selected glycine labelled in two 13C atoms (13C2-glycine) as labelled amino acid to demonstrate that spectral overlap is not a problem in the proposed methodology. The developed methodology was tested first in vitro by changing the precursor pool enrichment from 10 to 40%of 13C2-glycine. Secondly, a simulated in vivo synthesis of proteins was designed by combining the natural abundance RGGGLK peptide and 10 or 20% 13C2-glycine at 1 : 1, 1 : 3 and 3 : 1 ratios. Precursor pool enrichments and fractional synthesis values were calculated with satisfactory precision and accuracy using a simple spreadsheet. This novel approach can provide a relatively rapid and easy means to measure protein turnover based on stable isotope tracers. [ABSTRACT FROM AUTHOR]

α-Ethynyl glycine derivatives have a high potential for functionalization by derivatization of the amino acid or acetylene moiety, and, as a result, are important intermediates in the construction of biologically active compounds, including natural products. The main methods for the synthesis of ethynyl glycines and glycinols can be divided into six different transformations: (a) homologations of serinal derivatives, (b) nucleophilic alkynylations of α-imino esters/alcohols or their precursors α-halo glycinates, (c) derivatizations of alkynyl imino esters, (d) electrophilic alkynylations of α-nitro esters and azlactones by using hypervalent iodine reagents, (e) intra- and intermolecular aminolysis reactions of epoxides, and (f) propargylic aminations through the cyclization of bis(imidate). This microreview summarizes the methods that were published from 1996 to 2015. [ABSTRACT FROM AUTHOR]

Detecting genetic variation such as Copy Number Variants (CNVs) in cattle provides the opportunity to study their association with quantitative traits. CNVs are DNA sequences of 50 bp up to several Mb long, which can vary in copy number in comparison with a reference genome. The aim of this study was to investigate CNVs in 1410 samples of the Brown Swiss cattle breed using Illumina Bovine HD SNP chip information, which includes 777,962 SNPs. After stringent quality control, CNVs were called with the Golden Helix SVS 8.3.1 (SVS) and PennCNV software and were summarized to CNV regions (CNVRs) at a population level (i.e. overlapping CNVs), using BEDTools. Additionally, common CNVRs between the two software were set as consensus regions. Genes within consensus CNVRs were annotated with a GO analysis using the DAVID Bioinformatics Resources 6.7. In order to validate these results, quantitative PCRs were executed on 15 selected CNVRs. The SVS software identified 25,030 CNVs summarized to 398 CNVRs, which comprised 30 gains, 344 losses and 24 complex CNVRs (i.e. containing both losses and gains), covering 3.92% of the bovine genome. The PennCNV software identified 62,341 CNVs summarized to 5578 CNVRs, which comprised 2638 gains, 2404 losses and 537 complex CNVRs, covering 7.68% of the bovine genome. The length of these CNVRs ranged from 1244 bp to 1,381,355 bp. A total of 563 consensus CNVRs were found covering 2.29% of the UMD 3.1 bovine genome assembly. Of these, 24 were gains, 300 were losses and 239 were complex CNVRs. A total of 775 official gene IDs were annotated in the consensus CNVRs. Among the 537 genes with functional information, the GO and pathway analysis was reported for those who clustered with a p-value <0.05. The quantitative PCRs successfully validated 14 (93.33%) of the selected CNVRs. The result of this study is the first comprehensive genomic analysis of the Brown Swiss breed based on the Illumina Bovine HD SNP chip on such a large number of animals that enriches the CNV map in the bovine genome. These findings also provide valuable information for further CNV studies. Finally, the results of the CNVR map delivers new information for functional, health and productive traits considered in selection programs of the Brown Swiss breed. [ABSTRACT FROM AUTHOR]

A total of 250 one-day-old male broilers (Ross 308) were used to investigate the effects of dietary Zn-Gly (zinc glycine chelate) supplementation on growth performance, carcass characteristics, bone quality, and mineral content in bones. All broilers were randomly assigned to five treatment groups, each of which was replicated five times (10 birds in each cage). 5 groups were formed: control negative – CN (corn-wheat and soybean meal control diet with no supplementation of Zn), control positive – CP (CN+100 mg of Zn as oxide/kg of diet), and 3 groups with Zn-Gly supplementation at three doses: 25, 50, or 100 mg kg −1 (CN +25, 50, or 100 mg of Zn as glycine chelate/kg of diet). The experimental diets were fed to chicks for over 6 weeks. In the study, a positive trend to gain body weight and the weight of breast, thigh, and drumstick muscles was observed when organic Zn was introduced, in particular at a dose of 50 and 25 mg. The addition of Zn, regardless of its source, had an effect on the increase ( P <0.05) in the intake of feed. A considerable increase in values such as cross-sectional area (A), second moment of inertia (Ix), and mean relative wall thickness (MRWT) was found both in the femur and in the tibia in the group supplemented with 50 mg Zn-Gly. The use of Zn-Gly improved the quality of the tibia and femur and their strength parameters, perhaps due to the increased deposition of Ca and P in bones. The addition of Zn-Gly increased (P<0.05) the accumulation of Zn in bones. In conclusion, these results suggest that the supplementation of Zn-Gly in amounts lower than recommended has no negative effect on the production performance of Ross broiler chickens, which in turn suggests that such an amount of Zn is sufficient to ensure the optimum body weight and positive production performance and is the condition of correct ossification and mineralisation of the bone tissue. [ABSTRACT FROM AUTHOR]

DPP-4 inhibition is one of the most extensively explored approaches for the management of type 2 diabetes (T2D). Most DPP-4 inhibitors in the market contain a proline mimetic active pharmacophore. Herein, we report the design, synthesis, and preliminary evaluation of a series of novel diamide derivatives of glycine, devoid of the proline mimic, for the treatment of T2D. As predicted fromin silicostudies, the diamide derivatives of glycine exhibited comparable DPP-4 inhibition with the standard as confirmed by the preliminaryin vitrostudies. Compound6bwas found to be the most potent (IC5094.82 nM) DPP-4 inhibitor among all the molecules synthesized in the series. [ABSTRACT FROM AUTHOR]

Native human adult hemoglobin (Hb A) has mostly normal orientation of heme, whereas recombinant Hb A (rHb A) expressed in E. coli contains both normal and reversed orientations of heme. Hb A with the normal heme exhibits positive circular dichroism (CD) bands at both the Soret and 260-nm regions, while rHb A with the reversed heme shows a negative Soret and decreased 260-nm CD bands. In order to examine involvement of the proximal histidine (His F8) of either α or β subunits in determining the heme orientation, we prepared two cavity mutant Hbs, rHb(αH87G) and rHb(βH92G), with substitution of glycine for His F8 in the presence of imidazole. CD spectra of both cavity mutant Hbs did not show a negative Soret band, but instead exhibited positive bands with strong intensity at the both Soret and 260-nm regions, suggesting that the reversed heme scarcely exists in the cavity mutant Hbs. We confirmed by 1H NMR and resonance Raman (RR) spectroscopies that the cavity mutant Hbs have mainly the normal heme orientation in both the mutated and native subunits. These results indicate that the heme Fe-His F8 linkage in both α and β subunits influences the heme orientation, and that the heme orientation of one type of subunit is related to the heme orientation of the complementary subunits to be the same. The present study showed that CD and RR spectroscopies also provided powerful tools for the examination of the heme rotational disorder of Hb A, in addition to the usual 1H NMR technique. Chirality 28:585-592, 2016. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Deficiency of guanidinoacetate methyltransferase (GAMT) causes creatine depletion and guanidinoacetate accumulation in brain with the latter deemed to be responsible for the severe seizure disorder seen in affected patients. We studied electrical brain activity and GABA mediated mechanisms of B6J.Cg-Gamt mice. Electrocorticographic (ECoG) monitoring of pharmacological treatments with ornithine (5 % in drinking water for 5-18 days) and/or Picrotoxin (PTX) (a GABA receptor antagonist) (1.5 mg/kg, I.P.) in Gamt and Gamt groups [ n = 3, mean age (SEM) = 6.9 (0.2) weeks]. Mice were fitted with two frontal and two parietal epidural electrodes under ketamine/xylazine anesthesia. Baseline and test recordings were performed for determination of seizure activity over a 2 h period. The ECoG baseline of Gamt exhibited an abnormal monotonous cortical rhythm (7-8 Hz) with little variability during awake and sleep states compared to wild type recordings. Ornithine treatment and also PTX administration led to a relative normalization of the Gamt ECoG phenotype. Gamt on PTX exhibited electro-behavioral seizures, whereas the Gamt did not have PTX induced seizures at the same PTX dose. Gamt treated with both ornithine and PTX did not show electro-behavioral seizures while ornithine elevated the PTX seizure threshold of Gamt mice even further. These data demonstrate: (1) that there is expression of electrical seizure activity in this Gamt-deficient transgenic mouse strain, and (2) that the systemic availability of guanidinoacetate affects GABA receptor function and seizure thresholds. These findings are directly and clinically relevant for patients with a creatine-deficiency syndrome due to genetic defects in GAMT and provide a rational basis for a combined ornithine/picrotoxin therapeutic intervention. [ABSTRACT FROM AUTHOR]

Guanidinoacetic acid (GAA; also known as glycocyamine or guanidinoacetate) is the natural precursor of creatine, and under investigation as a novel dietary agent. It was first identified as a natural compound in humans ~80 years ago. In the 1950s, GAA's use as a therapeutic agent was explored, showing that supplemental GAA improved patient-reported outcomes and work capacity in clinical populations. Recently, a few studies have examined the safety and efficacy of GAA and suggest potential ergogenic benefits for physically active men and women. The purpose of this review is to examine possible applications of GAA supplementation for exercise performance enhancement, safety, and legislation issues. [ABSTRACT FROM AUTHOR]

A simple and efficient one-pot approach has been developed for a copper-catalyzed phosphorylation of glycine derivatives under air and at room temperature. The present cross-dehydrogenative coupling allows various methoxyphenyl-protected glycine derivatives to be phosphorylated using diverse alkyl and aryl phosphites through an oxidative coupling between C sp3−H and P−H bonds catalyzed by copper iodide. This method provides a new synthetic tool to obtain biologically active α-aminophosphonates. [ABSTRACT FROM AUTHOR]