The local adsorption site of the monotartrate and bitartrate species of R,R-tartaric acid deposited on Cu(110) have been determined by scanned-energy mode photoelectron diffraction (PhD). In the monotartrate phase the molecule is found to adsorb upright through the O atoms of the single deprotonated carboxylic acid (carboxylate) group, which are located in different off-atop sites with associat...

In the system sarcosine + L-tartaric acid + H2O we identified several new phases in addition to the previously known species sarcosinium hydrogen L-tartrate (I). Two of them (phases (II) and (III)) were obtained in the form of single crystals. Their crystal and molecular structures were determined. Both phases (II) and (III) have 2:1 composition and contain a zwitter-ionic sarcosine, a sarcosin...

The enzyme, 2-keto-3-deoxy-6-phosphogluconic aldolase is inactivated by the substrate analog, bromopyruvate. Inactivation results from either an active site carboxyl group or a cysteine being alkylated by bromopyruvate. Treatment of enzyme inactivated by carboxylate ester formation with borohydride produces the secondary amine resulting from reduction of a Schiff’s base between the covalently f...

the present study was carried out to investigate the potential of carboxylate group functionalized multi-walled carbon nanotubes (mwcnt−cooh) adsorbent for the removal of methyl orange (mo) textile dye from aqueous solutions. the effects of ph, shaking time and temperature on adsorption capacity were studied; the contact time to obtain equilibrium at 298 ˚k was fixed at 25 min. the effect of te...

(2)D, (13)C, (14)N, and (17)O NMR and crystallographic data from the literature were critically evaluated in order to provide a coherent hydration model of amino acids and selected derivatives at different ionization states. (17)O shielding variations, longitudinal relaxation times (T(1)) of (2)D and (13)C and line widths (Δν(1/2)) of (14)N and (17)O, may be interpreted with the hypothesis that...

The crystal structure of the complex of a catalytic antibody with its cationic hapten at 1.9-A resolution demonstrates that the hapten amidinium group is stabilized through an ionic pair interaction with the carboxylate of a combining-site residue. The location of this carboxylate allows it to act as a general base in an allylic rearrangement. When compared with structures of other antibody com...

Oseltamivir is a substrate of P-glycoprotein, an efflux drug transporter encoded by ABCB1. The objective of this study was to assess the role of ABCB1 (c.1236C>T, c.2677G>T/A, and c.3435C>T) polymorphisms in the pharmacokinetics of oseltamivir and its active metabolite, oseltamivir carboxylate in humans. Nineteen healthy male subjects were enrolled, and their ABCB1 polymorphisms were evaluated....

Relative interaction strengths between cations (X = Li (+), Na (+), K (+), NH 4 (+)) and anionic carboxylate groups of acetate and glycine in aqueous solution are determined. These model systems mimic ion pairing of biologically relevant cations with negatively charged groups at protein surfaces. With oxygen 1s X-ray absorption spectroscopy, we can distinguish between spectral contributions fro...

The crystal and molecular structures of 4-ethyl-3,5-dimethylpyrrole-2-carbaldehyde, C10H15NO, (I), benzyl 3,5-dimethylpyrrole-2-carboxylate, C14H15NO2, (II), benzyl 4-acetyl-3,5-dimethylpyrrole-2-carboxylate, C16H17NO3, (III), dimethyl 3,5-dimethylpyrrole-2,4-dicarboxylate, C10H13NO4, (IV), 4-ethyl-3,5-dimethyl-2-(p-tosylacetyl)pyrrole, C17H21NO3S, (V), and ethyl 4-(2-ethoxycarbonyl-2-hydroxyac...