A new naphthalene derivative containing a urea group at the 1,8-position of naphthalene was synthesized and showed a unique absorption and fluorescence peak with fluoride ion. Calculations suggested that a new peak was attributed to the increased anionic character of urea nitrogen due to the strongly charged hydrogen bonding between fluoride and amide protons of the urea. The fluoride selectivi...

We investigated the assignments and the conformational dependencies of the UV resonance Raman bands of the 21-residue mainly alanine peptide (AP) and its isotopically substituted derivatives in both their R-helical and PPII states. We also examined smaller peptides to correlate conformation, hydrogen bonding, and structure. Our vibrational mode analysis confirms the complex nature of the amide ...

MDL 62211 is the amide derivative of the teicoplanin complex and MDL 62873 is a more focused amide derivative of the teicoplanin A2-2 peak. Each investigational compound had nearly identical activity and was 2- to 16-fold more active than teicoplanin or vancomycin. The MDL 62873 MICs for 90% of the strains tested were as follows: Staphylococcus aureus, oxacillin susceptible, 0.12 micrograms/ml;...

Infrared spectroscopy is a powerful tool in protein science due to its sensitivity to changes in secondary structure or conformation. In order to take advantage of the full power of infrared spectroscopy in structural studies of proteins, complex band contours, such as the amide I band, have to be decomposed into their main component bands, a process referred to as curve fitting. In this paper,...

Synthetic procedures are described that allow access to a number of new Rh(III) complexes with the tetradentate bis-amide ligand N,N'-bis(2'-pyridinecarboxamide)1,8-naphthalene (LH2). These complexes have the formulae Rh(LH2)Cl3, Na[RhLX2] • H20 (X = Cl, CN) and [RhLA2]C104 (A = pyridine, 1-methylbenzotriazole). The compounds have been characterized by elemental analyses, conductivity measureme...

Bacterial translation termination is mediated by release factors RF1 and RF2, which recognize stop codons and catalyze hydrolysis of the peptidyl-tRNA ester bond. The catalytic mechanism has been debated. We proposed that the backbone amide NH group, rather than the side chain, of the glutamine of the universally conserved GGQ motif participates in catalysis by H-bonding to the tetrahedral tran...

A series of novel functional carbazole (Cbz)-based carboxylated monomers were synthesized and characterized. A Clauson-Kaas procedure, a deprotection step, amide coupling, and hydrolysis were utilized as key chemical reactions towards the multistep synthesis of monomers in good to excellent isolated yields. The design strategy was further extended to complex carbazole-COOH monomers incorporated...

Sucrose phosphorylase catalysed glycosylation of glyceric acid amide with complete regio- and diastereo-selectivity is studied. (R)-2-O-α-D-Glucopyranosyl glyceric acid amide was obtained in high yield from single-step transformation of racemic glyceric acid amide and sucrose. Non-productive binding of (S)-glyceric acid amide appeared to underlie strict enantiodiscrimination by the enzyme, thus...

[reaction: see text] We report for the first time that stoichiometric and even catalytic quantities of weak acids in aqueous solution can very efficiently catalyze amide isomerization in a carefully designed system in which a proton donor is situated so that intramolecular hydrogen bonding to the amide nitrogen is highly favored. Our results provide the first experimental verification that hydr...

We used ultraviolet resonance Raman (UVRR) spectra to examine the spatial dependence and the thermodynamics of R-helix melting of an isotopically labeled R-helical, 21-residue, mainly alanine peptide. The peptide was synthesized with six natural abundance amino acids at the center and mainly perdeuterated residues elsewhere. CR deuteration of a peptide bond decouples CR-H bending from N-H bendi...