Journal articles: 'Guanidinium groups'

1

Malinska, Maura, Miroslawa Dauter, and Zbigniew Dauter. "Geometry of guanidinium groups in arginines." Protein Science 25, no. 9 (July 4, 2016): 1753–56. http://dx.doi.org/10.1002/pro.2970.

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2

Galukhin, Andrey, Ilnaz Imatdinov, and Yuri Osin. "p-tert-Butylthiacalix[4]arenes equipped with guanidinium fragments: aggregation, cytotoxicity, and DNA binding abilities." RSC Advances 6, no. 39 (2016): 32722–26. http://dx.doi.org/10.1039/c6ra04733e.

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Thiacalix[4]arenes in 1,3-alternate conformation functionalized with guanidinium groups showed a strong dependence of the aggregation properties with the ratio of guanidinium/n-decyl fragments attached to phenolic groups.

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3

Balos, V., M. Bonn, and J. Hunger. "Quantifying transient interactions between amide groups and the guanidinium cation." Physical Chemistry Chemical Physics 17, no. 43 (2015): 28539–43. http://dx.doi.org/10.1039/c5cp04619j.

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4

Szabo, Jan, and Gerhard Maas. "Derivatives of the triaminoguanidinium ion, 4. O-Sulfonylation of N,N′,N″-tris(hydroxybenzylidenamino)guanidinium ions." Zeitschrift für Naturforschung B 71, no. 6 (June 1, 2016): 697–703. http://dx.doi.org/10.1515/znb-2016-0035.

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AbstractAll hydroxy groups of the N,N′,N″-tris(4-hydroxybenzylidenamino)guanidinium and N,N′,N″-tris(2,4-dihydroxybenzylidenamino)guanidinium ions could be sulfonylated in good yields to obtain three-fold or six-fold substituted and functionalized derivatives. The 2,4-dihydroxyphenyl containing precursors have been used to construct branched three-armed guanidinium derivatives bearing six dansyl or anthraquinone moieties.

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5

Hanke, Marcel, Niklas Hansen, Emilia Tomm, Guido Grundmeier, and Adrian Keller. "Time-Dependent DNA Origami Denaturation by Guanidinium Chloride, Guanidinium Sulfate, and Guanidinium Thiocyanate." International Journal of Molecular Sciences 23, no. 15 (August 1, 2022): 8547. http://dx.doi.org/10.3390/ijms23158547.

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Guanidinium (Gdm) undergoes interactions with both hydrophilic and hydrophobic groups and, thus, is a highly potent denaturant of biomolecular structure. However, our molecular understanding of the interaction of Gdm with proteins and DNA is still rather limited. Here, we investigated the denaturation of DNA origami nanostructures by three Gdm salts, i.e., guanidinium chloride (GdmCl), guanidinium sulfate (Gdm2SO4), and guanidinium thiocyanate (GdmSCN), at different temperatures and in dependence of incubation time. Using DNA origami nanostructures as sensors that translate small molecular transitions into nanostructural changes, the denaturing effects of the Gdm salts were directly visualized by atomic force microscopy. GdmSCN was the most potent DNA denaturant, which caused complete DNA origami denaturation at 50 °C already at a concentration of 2 M. Under such harsh conditions, denaturation occurred within the first 15 min of Gdm exposure, whereas much slower kinetics were observed for the more weakly denaturing salt Gdm2SO4 at 25 °C. Lastly, we observed a novel non-monotonous temperature dependence of DNA origami denaturation in Gdm2SO4 with the fraction of intact nanostructures having an intermediate minimum at about 40 °C. Our results, thus, provide further insights into the highly complex Gdm–DNA interaction and underscore the importance of the counteranion species.

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6

Matulková, Irena, Jan Fábry, Václav Eigner, Michal Dušek, Jan Kroupa, and Ivan Němec. "Isostructural Crystals of Bis(Guanidinium) Trioxofluoro-Phosphate/Phosphite in the Ratio 1/0, 0.716/0.284, 0.501/0.499, 0.268/0.732, 0/1—Crystal Structures, Vibrational Spectra and Second Harmonic Generation." Crystals 12, no. 12 (November 23, 2022): 1694. http://dx.doi.org/10.3390/cryst12121694.

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The title structures of bis(guanidinium) trioxofluorophosphate, bis(guanidinium) trioxofluorophosphate-phosphite (0.716/0.284), bis(guanidinium) trioxofluorophosphate-phosphite (0.501/0.499), bis(guanidinium) trioxofluorophosphate-phosphite (0.268/0.732), and bis(guanidinium) phosphite are crystal-chemically isotypic. Their structures correspond to the structure of bis(guanidinium) trioxofluorophosphate which was determined by Prescott, Troyanov, Feist & Kemnitz (Z. Anorg. Allg. Chem. 2002, 628, 1749–1755). The P and O atoms of the substituted trioxofluorophosphate and phosphite anions share the same positions while the P-F and P-Hhydrido are almost parallel and oriented in the same direction. Two symmetry-independent anions and two of three symmetry-independent cations are situated on the crystallographic mirror planes. The ions are interconnected by N-H⋯O hydrogen bonds of moderate strength. The most frequent graph set motif is R22(8), which involves interactions between the primary amine groups and the trioxofluorophosphate or phosphite O atoms. Fluorine, as well as the hydrido hydrogen, avoids inclusion into the hydrogen-bond network. The Hirshfeld surface analysis was also performed for the comparison of intermolecular interactions in the title structures of bis(guanidinium trioxofluorophosphate and bis(guanidinium) phosphite. The title crystals were also characterized by vibrational spectroscopy methods (FTIR and FT Raman) and the second harmonic generation (SHG). The relative SHG efficiency considerably decreases from bis(guanidinium) trioxofluorophosphate to bis(guanidinium) phosphite for the fundamental 1064 nm laser line.

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7

Balos, V., M. Bonn, and J. Hunger. "Correction: Quantifying transient interactions between amide groups and the guanidinium cation." Physical Chemistry Chemical Physics 18, no. 2 (2016): 1346–47. http://dx.doi.org/10.1039/c5cp90226f.

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8

Cui, Yu Fang, Jin Yan Du, Yu Ming Shang, Yao Wu Wang, Jin Hai Wang, Ya Fei Lv, and Shu Bo Wang. "Novel Anion Exchange Membranes from Poly(aryl ether)s with Quaternary Guanidinium Groups." Advanced Materials Research 560-561 (August 2012): 864–68. http://dx.doi.org/10.4028/www.scientific.net/amr.560-561.864.

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A series of fluorinated poly(aryl ether oxadiazole)s (FPEO) were synthesized and brominated with N-bromosuccinmide (NBS) which were then functionalized with quaternary guanidinium to get fluorinated anion exchange membranes （AEM）with pendant quaternary guanidinium Groups. The structure of resulting polymers was characterized by FTIR spectroscopy. The properties of the obtained membranes were investigated in terms of ion exchange capacity (IEC), swelling ratio, area resistance and vanadium permeability. The results showed that the novel anion exchange membranes possess much higher selectivity in VRB system. The permeation rate of vanadium ions of GFPEO is 0.21×10-7 cm2min-1 which is much lower compared with that of Nafion.

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9

Du, Shanshan, Yang Li, Zhilong Chai, Weiguo Shi, and Junlin He. "Site-specific functionalization with amino, guanidinium, and imidazolyl groups enabling the activation of 10–23 DNAzyme." RSC Advances 10, no. 32 (2020): 19067–75. http://dx.doi.org/10.1039/d0ra02226h.

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10

Tiritiris, Ioannis. "N,N,N′,N′,N′′-Pentamethyl-N′′-[3-(trimethylazaniumyl)propyl]guanidinium bis(tetraphenylborate)." Acta Crystallographica Section E Structure Reports Online 69, no. 2 (January 26, 2013): o292. http://dx.doi.org/10.1107/s1600536813001992.

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In the crystal structure of the title salt, C12H30N42+·2C24H20B−, the C—N bond lengths in the central CN3unit of the guanidinium ion are 1.3388 (17), 1.3390 (16) and 1.3540 (17) Å, indicating partial double-bond character in each. The central C atom is bonded to the three N atoms in a nearly ideal trigonal-planar geometry and the positive charge is delocalized in the CN3plane. The bonds between the N atoms and the terminalC-methyl groups of the guanidinium moiety, all have values close to a typical single bond [1.4630 (16)–1.4697 (17) Å]. C—H...π interactions are present between the guanidinium H atoms and the phenyl C atoms of one tetraphenylborate ion. The phenyl rings form a kind of aromatic pocket, in which the guanidinium ion is embedded.

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11

Kanvah, Sriram, and Gary B. Schuster. "Effect of positively charged backbone groups on radical cation migration and reaction in duplex DNA." Canadian Journal of Chemistry 89, no. 3 (February 2011): 326–30. http://dx.doi.org/10.1139/v10-145.

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A series of DNA oligomers were prepared that contain guanidinium linkages (positively charged) positioned selectively in place of and among the normal negatively charged phosphodiester backbone groups of duplex DNA. One-electron oxidation of these DNA oligomers by UV irradiation of a covalently linked anthraquinone group generates a radical cation (electron “hole”) that migrates by hopping through the DNA and is trapped at reactive sites, GG steps, to form mutated bases that are detected by strand cleavage after subsequent piperidine treatment of the irradiated DNA. Analysis of the strand cleavage pattern reveals that guanidinium substitution in these oligomers does not measurably affect the charge migration rate but it does inhibit reaction at nearby guanines.

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12

Sauer, Sven, Sarmenio Saliba, Stefan Tussetschläger, Angelika Baro, Wolfgang Frey, Frank Giesselmann, Sabine Laschat, and Willi Kantlehner. "p-Alkoxybiphenyls with guanidinium head groups displaying smectic mesophases." Liquid Crystals 36, no. 3 (May 22, 2009): 275–99. http://dx.doi.org/10.1080/02678290902850027.

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13

Robichon, Alain, and Jean Claude Marie. "Chemical modification of guanidinium groups of vasoactive intestinal peptide." Biochimica et Biophysica Acta (BBA) - General Subjects 923, no. 2 (February 1987): 250–56. http://dx.doi.org/10.1016/0304-4165(87)90010-9.

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14

Müller, Gerhard, Jürgen Riede, and Franz Peter Schmidtchen. "Host-Guest Bonding of Oxoanions to Guanidinium Anchor Groups." Angewandte Chemie International Edition in English 27, no. 11 (November 1988): 1516–18. http://dx.doi.org/10.1002/anie.198815161.

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15

Russell, V. A., and M. D. Ward. "Solid-state structure of a layered hydrogen-bonded salt: guanidinium 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonate methanol solvate." Acta Crystallographica Section B Structural Science 52, no. 1 (February 1, 1996): 209–14. http://dx.doi.org/10.1107/s0108768195009980.

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Guanidinium 5-benzoyl-4-hydroxy-2-methoxybenzene-sulfonate methanol solvate [C(NH2)3 +.(C14H11O3)SO3 −.CH3OH] crystallizes into a layered structure containing a two-dimensional hydrogen-bonded network typical of guanidinium alkane- and arenesulfonates. All six guanidinium protons and six sulfonate oxygen lone-pair acceptors participate in hydrogen bonding to form nearly planar pseudohexagonal hydrogen-bonded sheets, which can be viewed as parallel connected hydrogen-bonded ribbons. The 5-benzoyl-4-hydroxy-2-methoxybenzene groups are oriented to the same side of each ribbon, but the orientation of these groups on adjacent ribbons alternates with respect to the hydrogen-bonded sheet. The planar sheets stack with interdigitation of the arene groups, resulting in a structure in which layers of 5-benzoyl-4-hydroxy-2-methoxybenzene groups are separated by ionic hydrogen-bonded sheets. Each methanol molecule forms a hydrogen bond to one of the sulfonate O atoms, resulting in this oxygen forming a total of three hydrogen bonds, and fills void volume between the interdigitated 5-benzoyl-4-hydroxy-2-methoxybenzene groups of neighboring sheets. The benzophenone hydroxyl proton forms an intramolecular hydrogen bond to the carbonyl oxygen.

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16

Kantlehner, Willi, Jochen Mezger, Ralf Kreß, Horst Hartmann, Thorsten Moschny, Ioannis Tiritiris, Boyan Iliev, et al. "Orthoamide, LXIX [1]. Beiträge zur Synthese N,N,N´,N´,N´´-peralkylierter Guanidine und N,N,N´,N´,N´´䞲,N´´-persubstituierter Guanidiniumsalze / Orthoamides, LXIX [1]. Contributions to the Synthesis of N, N, N´, N´, N´-peralkylated Guanidines and N, N, N´, N´, N´´, N´´-persubstituted Guanidinium Salts." Zeitschrift für Naturforschung B 65, no. 7 (July 1, 2010): 873–906. http://dx.doi.org/10.1515/znb-2010-0712.

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N, N, N´, N´-Tetraalkyl-chloroformamidinium chlorides 6 are prepared from N, N, N´, N´-tetraalkylureas 5 and phosgene in acetonitrile. The iminium salts 6 react with primary and secondary amines in the presence of triethylamine to give N, N, N´, N´, N´´-pentasubstituted and N, N, N´, N´, N´´, N´´- hexasubstituted guanidinium salts 7 and 8, respectively, Treatment of the guanidinium salts 7 with sodium hydroxide in excess affords the N, N, N´N´, N´´-pentasubstituted guanidines 9a - 9aa. Additionally, the N, N, N´, N´, N´´-pentasubstituted and N, N, N´, N´, N´´, N´´-hexasubstituted guanidinium salts 7l´, 7p´ and 8a - c can be obtained from the reaction mixtures by addition of stoichiometric amounts of sodium hydroxide. A modified method is described for the preparation of guanidinium salts possessing dialkylamino substituents consisting of two long-chain alkyl groups (>C14). Some guanidines 9 were alkylated with allyl chloride and bromide, ethyl bromide, butyl bromide, benzyl bromide and chloride, dimethyl sulfate, diethyl sulfate, and methyl methansulfonate to give the corresponding guanidinium salts 11 - 15. By alkylation of the N, N, N´, N´, N´´-pentasubstituted guanidine 9v with triethyloxonium tetrafluoroborate the guandinium tetrafluoroborate 16a is accessible. N-Functionalized guanidinium salts 17 - 18a - c result from the reaction of N, N, N´, N´, N´´-pentasubstituted guanidines with ethyl bromoacetate and bromoacetonitrile, respectively, and subsequent anion exchange with sodium tetraphenylborate. N, N, N´, N´-Tetramethylguanidine (21) adds to ethyl acrylate to give the labile guanidine 22, which forms the guanidinium salt 23a on treatment with methyl iodide. Zwitterionic guanidinium salts 25 result, when N, N, N´, N´, N´´-pentasubstituted guanidines are treated with sultones 24.

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17

Wei, Bin. "Dimethylammonium guanidinium naphthalene-1,5-disulfonate." Acta Crystallographica Section E Structure Reports Online 68, no. 4 (March 21, 2012): o1123. http://dx.doi.org/10.1107/s1600536812011099.

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The asymmetric unit of the title salt, CH6N3+·C2H8N+·C10H6O6S22−, consists of one dimethylammonium cation, one guanidinium cation, and two half naphthalene-1,5-disulfonate anions, which lie on inversion centers. N—H...O hydrogen bonds link the cations and anions into layers parallel to theabplane. The layers have a sandwich-like structure, with the sulfonate groups and cations forming outer slices and the naphthalene ring systems inside.

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18

Vortman, M. Ya, Zh P. Kopteva, A. E. Kopteva, D. R. Abdulina, Yu B. Pysmenna, G. O. Iutynska, A. V. Rudenko, V. V. Tretyak, V. N. Lemeshko, and V. V. Shevchenko. "Antibacterial and Fungicidal Activity of Guanidinium Oligomers." Mikrobiolohichnyi Zhurnal 83, no. 4 (August 17, 2021): 86–97. http://dx.doi.org/10.15407/microbiolj83.04.086.

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Guanidinium oligomers are a poorly studied class of organic compounds and attract attention due to their antimicrobial properties. Strengthening the antimicrobial properties and simplifying and reducing the cost of the synthesis of these compounds is promising for obtaining functional guanidine-containing oligomers with alkyl radicals of different lengths in their composition. The aim of this work is to study the bactericidal and fungicidal activities of newly synthesized oligomeric guanidinium bromides with alkyl radicals of various lengths. Methods. The synthesis of tetraalkyl-substituted guanidine-containing oligomers with an aromatic and aliphatic oligoether component was carried out by the reaction of guanidine-containing oligomers with terminal guanidine fragments and alkyl bromides (Alk=-C3H7, -C7H15, -C10H21) at a molar ratio (1:4) of components. Different types of microorganisms (clinical isolates, gram-positive and gramnegative bacteria, microscopic fungi) were used as test cultures to determine the biocidal activity of the obtained compounds. The bacteria were grown on meat-peptone agar for 48 hours, micromycetes – on beer wort agar (6°B) for 14 days. The hydrocarbon-oxidizing bacteria and micromycetes were incubated at a temperature of 28±2°C, and clinical bacterial isolates – at a temperature of 37±2°C. Antimicrobial activity of oligomers was determined by the standard disco-diffusion method, and fungicidal – by the method of wells in agar. Results. Tetraalkyl-substituted guanidinium bromide oligomers with various radicals (-C3H7, -C7H15, -C10H21) were obtained and their bactericidal and fungicidal activity against various groups of microorganisms was shown. It was found that the obtained oligomers at a concentration of 1–3% in aqueous solution inhibited the growth of gram-negative and gram-positive bacteria. Antimicrobial and fungicidal properties depended on the length of the alkyl radical, and as its length increased, the diameter of growth inhibition zones of bacteria and micromycetes were increased. For 3% solutions of tetraalkyl-substituted guanidine oligomer with aromatic oligoepoxide (Alk=-C10H21), the growth inhibition zones of bacteria were 18–21 mm. The bactericidal effect of oligomer based on aromatic oligoepoxide with alkyl radicals Alk=-C7H15, -C10H21 was 20–25% higher than that for variants with aliphatic oligoepoxide. All the tetraalkyl-substituted (Alk=-C7H15, -C10H21) guanidine-containing oligomers at a concentration of 1% solution showed fungicidal activity to almost all micromycetes, the growth inhibition zones for microscopic fungi on the 7th day were 7–20 mm. The largest growth inhibition zones of micromycetes (in the range 15–20 mm) were observed for oligomers with aromatic oligoepoxide and radicals Alk=-C10H21 and -C7H15 and aliphatic oligoepoxide with radical Alk=-C10H21 (in the range 15–20 mm). Conclusions. The length of the alkyl radical and the nature of the oligoether component affected the bactericidal and fungicidal properties of newly synthesized oligomers. With an increase of the length of the alkyl radical of guanidine-containing oligomers, their bactericidal and fungicidal properties increase, tetralkyl-containing oligomers are promising for use as disinfectants for indoor treatment and as additives in polymer compositions to protect them from bio-damage.

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19

Tabujew, Ilja, Ceren Cokca, Leon Zartner, Ulrich S. Schubert, Ivo Nischang, Dagmar Fischer, and Kalina Peneva. "The influence of gradient and statistical arrangements of guanidinium or primary amine groups in poly(methacrylate) copolymers on their DNA binding affinity." Journal of Materials Chemistry B 7, no. 39 (2019): 5920–29. http://dx.doi.org/10.1039/c9tb01269a.

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20

Metzger, A., W. Peschke, and F. P. Schmidtchen. "A Convenient Access to Chiral Monofunctionalized Bicyclic Guanidinium Receptor Groups." Synthesis 1995, no. 05 (May 1995): 566–70. http://dx.doi.org/10.1055/s-1995-3953.

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21

Sapse, Anne-Marie, Robert Rothchild, and Kyu Rhee. "An ab initio study of the guanidinium groups in saxitoxin." Journal of Molecular Modeling 12, no. 2 (November 8, 2005): 140–45. http://dx.doi.org/10.1007/s00894-005-0005-y.

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22

Li, Shouchuan, Chunyu Chen, Zhengdong Zhang, Dong Wang, and Shanshan Lv. "Illustration and application of enhancing effect of arginine on interactions between nano-clays: self-healing hydrogels." Soft Matter 15, no. 2 (2019): 303–11. http://dx.doi.org/10.1039/c8sm02188k.

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23

Galukhin, Andrey, Anton Erokhin, Ilnaz Imatdinov, and Yuri Osin. "Investigation of DNA binding abilities of solid lipid nanoparticles based on p-tert-butylthiacalix[4]arene platform." RSC Advances 5, no. 42 (2015): 33351–55. http://dx.doi.org/10.1039/c5ra03814f.

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24

Tiritiris, Ioannis, and Willi Kantlehner. "Crystal structure ofN′′-benzyl-N′′-[3-(benzyldimethylazaniumyl)propyl]-N,N,N′,N′-tetramethylguanidinium bis(tetraphenylborate)." Acta Crystallographica Section E Crystallographic Communications 71, no. 12 (December 1, 2015): o1086—o1087. http://dx.doi.org/10.1107/s2056989015024639.

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In the crystal structure of the title salt, C24H38N42+·2C24H20B−, the C—N bond lengths in the central CN3unit of the guanidinium ion are 1.3364 (13), 1.3407 (13) and 1.3539 (13) Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3plane. The bonds between the N atoms and the terminal methyl groups of the guanidinium moiety and the four C—N bonds to the central N atom of the (benzyldimethylazaniumyl)propyl group have single-bond character. In the crystal, C—H...π interactions between the guanidinium H atoms and the phenyl C atoms of the tetraphenylborate ions are present, leading to the formation of a two-dimensional supramolecular pattern parallel to theacplane.

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25

Richter, Friederike, Liam Martin, Katharina Leer, Elisabeth Moek, Franziska Hausig, Johannes C. Brendel, and Anja Traeger. "Tuning of endosomal escape and gene expression by functional groups, molecular weight and transfection medium: a structure–activity relationship study." Journal of Materials Chemistry B 8, no. 23 (2020): 5026–41. http://dx.doi.org/10.1039/d0tb00340a.

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A library of cationic polyacrylamide homopolymers was synthesized and their gene delivery, endosomal release, and interaction with endosome-specific lipids were investigated. The guanidinium-containing polymers were most efficient.

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26

Castaneda, C. H., M. J. Scuderi, T. G. Edwards, G. D. Harris Jr., C. M. Dupureur, K. J. Koeller, C. Fisher, and J. K. Bashkin. "Improved antiviral activity of a polyamide against high-risk human papillomavirus via N-terminal guanidinium substitution." MedChemComm 7, no. 11 (2016): 2076–82. http://dx.doi.org/10.1039/c6md00371k.

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We report the synthesis of two novel pyrrole–imidazole polyamides with N-terminal guanidinium or tetramethylguanidinium groups and evaluate their antiviral activity against three cancer-causing HPV strains.

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27

Salama, Ahmed, Mohamed Hasanin, and Peter Hesemann. "Synthesis and antimicrobial properties of new chitosan derivatives containing guanidinium groups." Carbohydrate Polymers 241 (August 2020): 116363. http://dx.doi.org/10.1016/j.carbpol.2020.116363.

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28

Zhu, Xuzhi, Jie Yang, and Kirk S. Schanze. "Conjugated polyelectrolytes with guanidinium side groups. Synthesis, photophysics and pyrophosphate sensing." Photochem. Photobiol. Sci. 13, no. 2 (2014): 293–300. http://dx.doi.org/10.1039/c3pp50288k.

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29

SCHMIDTCHEN, F. P., M. BERGER, A. METZGER, K. GLOE, and H. STEPHAN. "ChemInform Abstract: Foldable Anion Hosts Based on Bicyclic Guanidinium Anchor Groups." ChemInform 28, no. 51 (August 2, 2010): no. http://dx.doi.org/10.1002/chin.199751316.

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30

Tanaka, Masato, Hans-Ullrich Siehl, Tillmann Viefhaus, Wolfgang Frey, and Willi Kantlehner. "An ONIOM Study of a Guanidinium Salt Ionic Liquid. Experimental and Computational Characterization of N,N,N`,N`,N``-Pentabutyl-N``-benzylguanidinium Bromide." Zeitschrift für Naturforschung B 64, no. 6 (June 1, 2009): 765–72. http://dx.doi.org/10.1515/znb-2009-0624.

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The guanidinium salt-based ionic liquid N,N,N`,N`,N``-pentabutyl-N``-benzyl-guanidinium bromide was synthesized and characterized by 1H and 13C NMR spectroscopy in solution and by single crystal X-ray structure analysis. The MO computational hybrid method of Morokuma and coworkers (ONIOM method) is applied to compare experimental and quantum chemical results. Four calculation models for two layer ONIOM calculations are defined based on differences of the area for the high-level layer region. Optimized geometries, interaction energies between the cation and the anion, and atomic charges are compared to data of full-QM calculations for the optimized geometry as well as of an experimental X-ray structure determination. The results indicate that it is mandatory for obtaining reasonable results that the parts of the substituent groups which are directly bound to the amino nitrogen atoms are included into the high-level layer. This least required ONIOM model for guanidinium-type ionic liquids can save computational cost of 90% compared to the full-QM SCF calculation.

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31

Grogg, Marcel, Donald Hilvert, Albert Beck, and Dieter Seebach. "Syntheses of Cyanophycin Segments for Investigations of Cell-Penetration." Synthesis 51, no. 01 (June 28, 2018): 31–39. http://dx.doi.org/10.1055/s-0037-1610202.

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Novel guanidinium-rich oligopeptide derivatives R-[Adp(X)]8-NH2 are described, which consist of an octa-aspartic acid backbone with argininylated side chains that are derived from the biopolymer cyanophycin [H-(Adp)n-OH]. The Fmoc-Adp(X,Pbf)-OH building blocks for solid-state peptide synthesis (SSPS) of Adp octamers were prepared from Fmoc-Arg(Pbf)-OH and Fmoc-Asp-OAll. Coupling on PAL resin provided four octamers with and without N-terminal fluorescent groups (FAM) and C-terminal amide groups. Milligram quantities of Adp-octamers were isolated after preparative HPLC purification. The structure of the novel guanidinium-rich oligomers is unique insofar as the side chains of the Asp8-backbone include both a guanidino and a carboxylic acid group, the influence of which will be tested with the corresponding ester and amide derivatives that were synthesized in parallel. Unusual cell-penetrating properties of the Adp-octamers are expected.

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32

METZGER, A., W. PESCHKE, and F. P. SCHMIDTCHEN. "ChemInform Abstract: A Convenient Access to Chiral Monofunctionalized Bicyclic Guanidinium Receptor Groups." ChemInform 26, no. 49 (August 17, 2010): no. http://dx.doi.org/10.1002/chin.199549189.

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33

Zhou, Zhe, Cansu Ergene, and Edmund F. Palermo. "Guanidinium-Functionalized Photodynamic Antibacterial Oligo(Thiophene)s." MRS Advances 4, no. 59-60 (2019): 3223–31. http://dx.doi.org/10.1557/adv.2019.359.

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ABSTRACTWe synthesized precision oligomers of thiophene with cationic and hydrophobic side chains to mimic the charge, hydrophobicity, and molecular size of antibacterial host defense peptides (HDPs). In this study, the source of cationic charge was a guanidinium salt moiety intended to reflect the structure of arginine-rich HDPs. Due to the pi-conjugated oligo(thiophene) backbone structure, these compounds absorb visible light in aqueous solution and react with dissolved oxygen to produce highly biocidal reactive oxygen species (ROS). Thus, the compounds exert bactericidal activity in the dark with dramatically enhanced potency upon visible light illumination. We find that guanylation of primary amine groups enhanced the activity of the oligomers in the dark but also mitigated their light-induced activity enhancement. In addition, we also quantified their toxicity to mammalian cell membranes using a hemolysis assay with red blood cells, in the light and dark conditions.

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Xue, Boxin, Fen Wang, Jifu Zheng, Shenghai Li, and Suobo Zhang. "Highly stable polysulfone anion exchange membranes incorporated with bulky alkyl substituted guanidinium cations." Molecular Systems Design & Engineering 4, no. 5 (2019): 1039–47. http://dx.doi.org/10.1039/c9me00064j.

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Hildebrandt, Peter, Roman S. Czernuszewicz, Christine A. Grygon, and Thomas G. Spiro. "Ultraviolet resonance Raman enhancement of the carboxylate and guanidinium groups in amino acids." Journal of Raman Spectroscopy 20, no. 10 (October 1989): 645–50. http://dx.doi.org/10.1002/jrs.1250201003.

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Song, Yongbo, Hongyan Zheng, Yulan Niu, Ying Yao, and Rongqian Meng. "Synthesis and Properties of Alkyl Bis-Guanidinium Acetates Surfactants." Tenside Surfactants Detergents 58, no. 2 (March 1, 2021): 127–35. http://dx.doi.org/10.1515/tsd-2019-2241.

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Abstract Novel surfactants with double hydrophilic groups (cocopropane and tallowpropane bis-guanidinium acetates), were synthesized and tested to evaluate both the basic surfactant properties and the unique application performance. Surface tension, conductivity and contact angle measurements were used to study the self-aggregation behavior in aqueous solution. Aggregation parameters were calculated such as adsorption efficiency and effectiveness (pC20 and CAC/C20), the maximum surface excess concentration (Гmax) and minimum surface area permolecule (Amin). The thermodynamic parameters of aggregation based conductivity measurements revealed that the aggregation process was spontaneous and entropy-driven. Compared to DTAC and CTAC, the alkyl bis-guanidinium acetates showed a higher emulsification capacity with both liquid kerosene and soybean oil. The evaluation of antimicrobial activity showed that the alkyl bisguanidinium acetates exhibited strong antibacterial activity against the tested strains at a concentration of 50 ppm.

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Kurzmeier, H., and F. P. Schmidtchen. "Abiotic anion receptor functions. A facile and dependable access to chiral guanidinium anchor groups." Journal of Organic Chemistry 55, no. 12 (June 1990): 3749–55. http://dx.doi.org/10.1021/jo00299a013.

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Chen, Xiaoqiang, Jingyun Wang, Shiguo Sun, Jiangli Fan, Song Wu, Jianfeng Liu, Saijian Ma, Lizhu Zhang, and Xiaojun Peng. "Efficient enhancement of DNA cleavage activity by introducing guanidinium groups into diiron(III) complex." Bioorganic & Medicinal Chemistry Letters 18, no. 1 (January 2008): 109–13. http://dx.doi.org/10.1016/j.bmcl.2007.11.001.

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Liu, Fang, Yanhua Wang, and Guo-Yuan Lu. "Bilayer Vesicle Formation in Ethanol from Calix[4]arene Derivative with Two Guanidinium Groups." Chemistry Letters 34, no. 10 (October 2005): 1450–51. http://dx.doi.org/10.1246/cl.2005.1450.

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Suresh, J., R. V. Krishnakumar, and S. Natarajan. "L-Argininium trifluoroacetate." Acta Crystallographica Section E Structure Reports Online 62, no. 7 (June 30, 2006): o3127—o3129. http://dx.doi.org/10.1107/s1600536806024743.

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In the title compound, C6H16N4O2 +·C2F3O2 −, the amino acid exists as a zwitterionic argininium cation, with positively charged amino and guanidinium groups and a negatively charged carboxylate group. The trifluoroacetic acid molecule is deprotonated. The stoichiometry between the argininium ion and the trifluoroacetate anion is 1:1. The aggregation of argininium cations and trifluoroacetate anions is strikingly similar to those observed in the 1:2 stoichiometric analogue.

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Schug, Kevin A., and Wolfgang Lindner. "Noncovalent Binding between Guanidinium and Anionic Groups: Focus on Biological- and Synthetic-Based Arginine/Guanidinium Interactions with Phosph[on]ate and Sulf[on]ate Residues." Chemical Reviews 105, no. 1 (January 2005): 67–114. http://dx.doi.org/10.1021/cr040603j.

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42

Wang, Sheng Qin, Mohit Sharma, and Yew Wei Leong. "Polyamide 11/Clay Nanocomposite Using Polyhedral Oligomeric Silsesquioxane Surfactants." Advanced Materials Research 1110 (June 2015): 65–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1110.65.

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This paper reports polyamide 11 (PA11)/layered silicate (clay) nanocomposite using polyhedral oligomeric silsesquioxane (POSS) surfactants. POSS functionalized with amino, ammonium and guanidinium groups were synthesized and used to facilitate the intercalation of polymer chains between silicate layers thereby to improve the dispersion of clay in polymer matrix. Nanocomposites from the blends of POSS-modified clay and PA11 were thus formulated via melting compounding and their mechanical and physical properties were characterized.

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MORILLAS, Manuel, Martin L. GOBLE, and Richard VIRDEN. "The kinetics of acylation and deacylation of penicillin acylase from Escherichia coli ATCC 11105: evidence for lowered pKa values of groups near the catalytic centre." Biochemical Journal 338, no. 1 (February 8, 1999): 235–39. http://dx.doi.org/10.1042/bj3380235.

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Penicillin G acylase catalysed the hydrolysis of 4-nitrophenyl acetate with a kcat of 0.8 s-1 and a Km of 10 µM at pH 7.5 and 20 °C. Results from stopped-flow experiments fitted a dissociation constant of 0.16 mM for the Michaelis complex, formation of an acetyl enzyme with a rate constant of 32 s-1 and a subsequent deacylation step with a rate constant of 0.81 s-1. Non-linear Van't Hoff and Arrhenius plots for these parameters, measured at pH 7.5, may be partly explained by a conformational transition affecting catalytic groups, but a linear Arrhenius plot for the ratio of the rate constant for acylation relative to KS was consistent with energy-compensation between the binding of the substrate and catalysis of the formation of the transition state. At 20 °C, the pH-dependence of kcat was similar to that of kcat/Km, indicating that formation of the acyl-enzyme did not affect the pKa values (6.5 and 9.0) of an acidic and basic group in the active enzyme. The heats of ionization deduced from values of pKa for kcat, which measures the rate of deacylation, are consistent with α-amino and guanidinium groups whose pKa values are decreased in a non-polar environment. It is proposed that, for catalytic activity, the α-amino group of the catalytic SerB1 and the guanidinium group of ArgB263 are required in neutral and protonated states respectively.

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Grijalvo, Santiago, Montserrat Terrazas, Anna Aviñó, and Ramón Eritja. "Stepwise synthesis of oligonucleotide–peptide conjugates containing guanidinium and lipophilic groups in their 3′-termini." Bioorganic & Medicinal Chemistry Letters 20, no. 7 (April 2010): 2144–47. http://dx.doi.org/10.1016/j.bmcl.2010.02.049.

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Andreyko, Elena A., Joshua B. Puplampu, Patricia A. Ignacio-De Leon, Ilya Zharov, and Ivan I. Stoikov. "p-tert-Butylthiacalix[4]arenes containing guanidinium groups: synthesis and self-assembly into nanoscale aggregates." Supramolecular Chemistry 31, no. 7 (June 16, 2019): 473–83. http://dx.doi.org/10.1080/10610278.2019.1628231.

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Aït-Haddou, Hassan, Jun Sumaoka, Sheryl L. Wiskur, J. Frantz Folmer-Andersen, and Eric V. Anslyn. "Remarkable Cooperativity between a ZnII Ion and Guanidinium/Ammonium Groups in the Hydrolysis of RNA." Angewandte Chemie International Edition 41, no. 21 (November 4, 2002): 4013–16. http://dx.doi.org/10.1002/1521-3773(20021104)41:21<4013::aid-anie4013>3.0.co;2-y.

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VORTMAN, M. YA, V. N. LEMESHKO, L. A. GONCHARENKO, S. M. KOBYLINSKIY, V. V. SHEVCHENKO, and S. N. OSTAPIUK. "OLIGOMERIC GUANIDINE-CONTAINING PROTON CATIONIC IONIC LIQUID." Polymer journal 43, no. 4 (November 26, 2021): 304–10. http://dx.doi.org/10.15407/polymerj.43.04.304.

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Oligomeric ionic liquids occupy an intermediate position between low molecular weight and polymeric. They are promising as polymer electrolytes in electrochemical devices for various purposes, membranes for the separation of gas mixtures, in sensor technologies, and so on. Oligomeric guanidinium ionic liquids are practically not described in the literature. In terms of studying the effect of the structure of the epoxy component on the properties of oligomeric ionic liquids of this type, it is advisable to introduce into its composition an aliphatic oligoether component. The choice of aliphatic oligoepoxide for the synthesis of guanidinium oligomeric ionic liquids is based on the fact that it is structurally similar to poly - and oligoethylene oxides, which are known to be non-toxic, biodegradable, and reactive oligomeric ionic liquids at elevated temperatures. A new type of reactive oligomeric proton cationic ionic liquid was synthesized by the reaction of oligomeric aliphatic diepoxide with guanidine, followed by neutralization of the product with hydrochloric acid. In this study, the synthesis of proton cationic oligomeric ionic liquids was based on the introduction of guanidinium fragments as end groups of the oligoether aliphatic chain. This reaction is attractive because of the ease of opening the oxirane ring with such a strong nucleophile as guanidine.The reaction forms a fragment with an aliphatic C-N bond, which retains the high basicity of the nitrogen atom. Its structure is characterized by the presence of guanidinium groups at the ends of the aliphatic hydroxyl-containing oligoether chain. The chemical structure of this compound is characterized by IR -, 1H ,13 C NMR spectroscopy methods, and its molecular mass characteristics are determined.The average molecular weight of the synthesized oligomeric ionic liquids is 610 g / mol.The value of the coefficient of polydispersity of the synthesized oligomeric ionic liquids is equal to 1.2. Determination of the content of amino groups in the guanidine-containing oligomer in the basic form by titrometric method allowed to establish that the value found is close to the theoretically calculated value. The synthesized oligomeric proton ionic liquid is characterized by an amorphous structure with two glass transition temperatures. The first lies in the range -70 °C, the second in the region of 70 °C, and the beginning of thermal oxidative destruction is located in the region of 148 °C. The temperature dependence of the ionic conductivity for this compound is nonlinear in the Arrhenius coordinates, which indicates the realization of ionic conductivity mainly due to the free volume in the system. The proton conductivity of this compound is 6.4·10-5–1·10-2Cm/cmin the range of 20–100 °C. The obtained compound exhibits surface-active properties characteristic of classical surfactants, as evidenced by the value of the limiting surface activity – 2.8·102 Nm2 / kmol. The value of CCM is 1.8·10-2 mol/l., and the value of the minimum surface tension – 37.70 mN / m. The synthesized oligomeric ionic liquid is of interest as electrolytes operating under anhydrous conditions, surfactants, disinfectants, and starting reagents for the synthesis of ion-containing blockopolymers.

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Roig, Victoria, and Ulysse Asseline. "Oligo-2‘-deoxyribonucleotides Containing Uracil Modified at the 5-Position with Linkers Ending with Guanidinium Groups." Journal of the American Chemical Society 125, no. 15 (April 2003): 4416–17. http://dx.doi.org/10.1021/ja029467v.

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Perreault, Denise M., Larry A. Cabell, and Eric V. Anslyn. "Using guanidinium groups for the recognition of RNA and as catalysts for the hydrolysis of RNA." Bioorganic & Medicinal Chemistry 5, no. 6 (June 1997): 1209–20. http://dx.doi.org/10.1016/s0968-0896(97)00051-5.

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Deng, Qiliang, Jianhua Wu, Yang Chen, Zhijun Zhang, Yang Wang, Guozhen Fang, Shuo Wang, and Yukui Zhang. "Guanidinium functionalized superparamagnetic silica spheres for selective enrichment of phosphopeptides and intact phosphoproteins from complex mixtures." J. Mater. Chem. B 2, no. 8 (2014): 1048–58. http://dx.doi.org/10.1039/c3tb21540g.

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Journal articles on the topic 'Guanidinium groups'

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