In the title compound, [Cu(ClO(4))(C(2)H(3)N)(C(15)H(19)N(3)O)]ClO(4), the Cu(II) ion is coordinated by three N atoms and a hydroxyl-O atom of the tetra-dentate ligand, an O atom of a perchlorate ion and an N atom of an acetonitrile ligand giving a tetra-gonally distorted octa-hedral environment around the copper(II) atom. There is an offset inter-complex face-to-face π-π inter-action [centroid...

Methanol dimer (CD3OH)2 ion–molecule reaction is initialized by VUV ~vacuum ultraviolet! laser photoionization. The proton and deuteron transfers are the dominant reactions. The relative probabilities of deuteron transfer from the methyl group and proton from the hydroxyl group were measured as a function of VUV photon energy between 10.91 to 10.49 eV. According to those results, the probabilit...

1. Evidence is presented that pepsin is a univalent acid with a value for pK of 6.85 (or a base, with pK 7.39). 2. The autodestruction of the pepsin is shown to be dependent in part upon an instantaneous irreversible change occurring in the ionized form of the enzyme (if it be an acid) or in the unionized form (if it be a base). 3. A further progressive autodestruction of pepsin at any given hy...

Complex formation and intermolecular excited-state proton transfer (ESPT) between a dihydroxy-1,8-naphthalimide photoacid and organic bases are investigated in polar aprotic solvents. First, quantum chemical calculations are used to explore the acid-base and spectroscopic properties and to identify energetically favorable complexes. The two hydroxyl groups of the photoacid enable stepwise forma...

Hollow magnetic porous Fe(3)O(4)/α-FeOOH microspheres, with abundant surface hydroxyl groups and carbonate-like species, were prepared using a simple template free solution method. The obtained magnetic microspheres were characterized by field emission scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption isotherms, vibrating sample magnetometry and X-ra...

1. The hydrolysis of gelatin at a constant hydrogen ion concentration follows the course of a monomolecular reaction for about one-third of the reaction. 2. If the hydrogen ion concentration is not kept constant the amount of hydrolysis in certain ranges of acidity is proportional to the square root of the time (Schütz's rule). 3. The velocity of hydrolysis in strongly acid solution (pH less th...

In the presence of magnesium ions, cleavage by the hammerhead ribozyme RNA at a specific residue leads to 2'3'-cyclic phosphate and 5'-OH extremities. In the cleavage reaction an activated ribose 2'-hydroxyl group attacks its attached 3'-phosphate. Molecular dynamics simulations of the crystal structure of the hammerhead ribozyme, obtained after flash-freezing of crystals under conditions where...

ABSTRACTIntroduction: The bioactivity property of pulp capping materials is determined by the hydroxyl ion release ability, which may alter environmental pH to become alkaline. Calcium silicate-based are antibacterial, able induce reparative dentin and have a good bacteria-tight seal. poor handling calcium can be overcome adding resin, so will easier handle. Therefore, purpose this study was sy...

2-Benzyl-5-hydroxy-4-oxopentanoic acid 1 and its enantiomers were designed, synthesized and assayed for inhibitory activity against carboxypeptidase A (CPA, EC 3.4.17.1). To verify the role of the terminal hydroxyl group in 1 binding to CPA, 2-benzyl-5benzyloxy-4-oxopentanoic acid 2 was also synthesized and evaluated. The inhibition constants show that both L-1 and D-1 were shown to have strong...