Chiral macrocycles with eight (R)- and (S)-methylbenzylurea residues on the resorcinarene skeleton linked through a hexyl or dodecyl spacer having amide linkages have been prepared by the reactions of the corresponding octaamine derivative with (R)- and (S)-alpha-methylbenzylisocyanate, respectively. In chloroform, the urea-functionalized resorcinarenes with hexyl spacers form intramolecular hy...

This paper reports a comparison of adhesion behavior urea-formaldehyde (UF) with those melamine-urea-formaldehyde (MU) resins in bonding wood by analyzing the results published literatures. For this purpose, UF prepared blending low-viscosity resin (LVR) high-viscosity (HVR) at five different and two formaldehyde/urea (F/U) molar ratios (1.0 1.2) was compared MUF synthesized either simultaneous...

This work focuses on the stability and supramolecular structure of betaine-urea-water (B:U:W) natural deep eutectic solvent. Solutions spanning a range molar ratios betaine, urea, water were prepared, varying temperature preparation times, analyzed by attenuated total reflection Fourier-transform infrared spectroscopy Nuclear Magnetic Resonance. Density Functional Theory Natural Bond Orbital an...

hydroquinazoline-2,5-dione was obtained from Biginelli-type cyclocondensation1 of 5,5-dimethylcyclohexane-1,3-dione with urea and 4-bromobenzaldehyde: yield 1.16 g (62.19%), m.p. 174 – 175 ̊C. A summary of the key crystallographic information is given in Table 1. The atomic coordinates and equivalent isotropic displacement parameters with estimated standard deviations for atoms except H are list...

Hydrogen bonding with fluoride is a key interaction encountered when analyzing the mode of action of 5'-fluoro-5'-deoxyadenosine synthase, the only known enzyme capable of catalyzing the formation of a C-F bond from F-. Further understanding of the effect of hydrogen bonding on the structure and reactivity of complexed fluoride is therefore important for catalysis and numerous other application...

OBJECTIVES Three activated organofunctional silane coupling agents alone and blended with a non-functional cross-linker silane were evaluated as adhesion promoters in an experiment where a bis-GMA (bis-phenol-A-diglycidyldimethacrylate) resin was bonded to silicatized titanium. The adhesive performances of the silanes were assessed as shear bond strength values. MATERIALS AND METHODS 3-Methac...

Attempts were made to assess the role of thiols and to determine the cathepsins involved in the degradation of serum albumin in mouse liver and kidney lysosomes. Unlike cysteine or beta-mercaptoethanol, reduced glutathione (GSH) did not stimulate the degradation of formaldehyde-treated albumin in liver lysosomes, suggesting that the tripeptide did not penetrate the membrane. However, GSH was a ...