The guanidine hybrid ligands, (tetramethylguanidine)methylenepyridine (TMGpy) and (dimethylethyleneguanidine)methylenepyridine (DMEGpy), were proven to be able to stabilize copper complexes active in the solvent-free polymerization of styrene at 110 °C using 1-phenylethylbromide as the initiator. The polymerization proceeded after first-order kinetics, and polystyrenes with polydispersities aro...

In the title compound, C(20)H(15)Cl(2)N(3)O, a typical polysubstituted guanidine with normal geometric parameters, the torsion angles [C-N-C-O = 3.8 (2), N-C-N-C = -6.1 (2)°] indicate that the guanidine and carbonyl groups are almost coplanar, due to the pseudo-hexa-gonal ring formed by intra-molecular N-H⋯O hydrogen bonds. The crystal packing is stabilized by inter-molecular N-H⋯O hydrogen bon...

We have characterized the guanidine-induced unfolding of both yeast and bovine ubiquitin at 25 degrees C and in the acidic pH range on the basis of fluorescence and circular dichroism measurements. Unfolding Gibbs energy changes calculated by linear extrapolation from high guanidine unfolding data are found to depend very weakly on pH. A simple explanation for this result involves the two follo...

A sequential dissociative extraction scheme is described in which tooth matrix proteins are extracted first in 4 M guanidine HCl, pH 7.4, and then in 4 M guanidine HCl, 0.5 M EDTA, pH 7.4, both with protease inhibitors present. The latter step dissolves the mineralized portion of the tissue and extracts noncollagenous proteins closely associated with hydroxyapatite crystallites in the mineraliz...

Compounds with excellent receptor engagement displaying ?2-AR antagonist activity are useful not only for therapeutic purposes (e.g. antidepressants), but also to help in the crystallization of this particular GPCR. Therefore, based on our broad experience topic, we have prepared eighteen di-aryl (phenyl and/or pyridin-2-yl) mono- or di-substituted guanidines and 2-aminoimidazolines. The vitro ...

The protection influence of three sulfa guanidine azo derivatives against nickel corrosion was studied in 0.5 M HCl solutions at 25oC. Measurements were conducted under various experimental conditions using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. These studies have shown that sulfa guanidine azo deriva...

We investigated in rat hippocampus neurons whether 4-(aminobutyl)guanidine (agmatine), formed by decarboxylation of L-arginine by arginine decarboxylase and metabolized to urea and putrescine, can modulate the function of N-methyl-D-aspartate (NMDA) receptor channels. In cultured hippocampal neurons studied by whole-cell patch clamp, extracellular-applied agmatine produced a voltage- and concen...

Four synthesized biocidal guanidine hydrochloride polymers with different alkyl chain length, including polyhexamethylene guanidine hydrochloride and its three new analogs, were used to investigate their interactions with phospholipids vesicles mimicking bacterial membrane. Characterization was conducted by using fluorescence dye leakage, isothermal titration calorimetry, and differential scann...

Various aspects of the interaction of oestrogen-receptor complexes with calf uterine chromatin covalently coupled to cellulose were analysed. Partially purified [3H]oestradiol-receptor complexes were bound to intact, or partially deproteinized, chromatin resins. Proteins were removed from the chromatin-cellulose resins by extraction with high molarities of salt, including NaCl/urea, guanidine h...

Riboswitches are structural elements found in mRNA molecules that couple small-molecule binding to regulation of gene expression, usually by controlling transcription or translation. We have determined high-resolution crystal structures of the ykkC guanidine III riboswitch from Thermobifida fusca. The riboswitch forms a classic H-type pseudoknot that includes a triple helix that is continuous w...