Equilibrium amide hydrogen exchange studies of barstar have been carried out at pH 6.7, 32 degrees C using one- and two-dimensional nuclear magnetic resonance. An unusually large fraction of the backbone amide hydrogens of barstar exchange too fast to be measured, and the exchange rates of only fifteen slow-exchanging amide sites including indole amides of two tryptophans could be measured in t...

The N-methylacetamide molecule (NMA) is an important model for peptide and protein vibrational spectroscopy as it contains the main amide chromophore. In the past, some observed NMA geometry and spectral features could not be entirely explained at the harmonic level or by a single-conformer model. In particular, the spectra were found to be very dependent on molecular environment. In this work ...

both as crystals and in solution.1–3 There are rare examples of trans amide of N-methyl aromatic anilide in crystals, though the introduction of methyl group(s) ortho to the amide bond reduces the ratio of the cis-amide form of N-methylbenzanilides in solution.3 In this paper, we report on the crystal structure of 1,2-bis(N-2-fluorobenzoyl-N-methylamino)benzene (1, Fig. 1), which has two trans-...

Caffeic acid phenyl ester is distributed wildly in nature and has antidiabetic and cardiovascular protective effects. However, rapid decomposition by esterase leads to its low bioavailability in vivo. In this study, chronic metabolic and cardiovascular effects of oral caffeic acid phenylethyl amide, whose structure is similar to caffeic acid phenyl ester and resveratrol, were investigated in IC...

An empirical correction to amide group vacuum force fields is proposed in order to account for the influence of the aqueous environment on the CvO stretching vibration ~amide I!. The dependence of the vibrational absorption spectral intensities on the geometry is studied with density functional theory methods at the BPW91/6-31G** level for N-methyl acetamide interacting with a variety of of wat...

Doubly protonated substance P and two analogs alkylated at the ninth position was studied to determine the effect of N-alkylation of the amide nitrogen on the electrospray ionization/surface-induced dissociation (ESI/SID) fragmentation pattern. Thermal decomposition experiments and ab initio calculations were also used in conjunction with the ESI/SID experiments. The increase in relative abunda...

125I-labelled GLP-I(7-36)amide was cross-liked to a specific binding protein in rat lung membranes using disuccinimidyl suberate. A single radio-labelled band at Mr 66,000 was identified by SDS-PAGE after solubilization of the ligand-binding protein complex which is consistent with the presence of a single class of binding sites on rat lung membranes. The band was undetectable when 1 mumol/l GL...

It has previously been demonstrated that the C-terminal alanyl residue in the B-chain of porcine insulin can be exchanged with a threonyl residue in a carboxypeptidase Y catalyzed transpeptidation reaction using threonine amide as nucleophile. However, with this procedure the transpeptidation product, human insulin amide, was obtained in relatively low yields. In the present paper it is demonst...

Two independent mol-ecules with quite similar conformations, A and B, comprise the asymmetric unit of the title compound, C23H21N3O2S. The terminal amide substituent is coplanar with the attached benzene ring [the O-C-C-C torsion angles are 174.0 (2) (A) and 6.3 (3)° (B)]. In the same way, the central amide group [C-C-C-O = 7.8 (3) (A) and 11.5 (3)° (B)] is approximately coplanar with the ring ...

BACKGROUND Glucagon-like peptide-1 (GLP-1) therapies are routinely used for glycaemic control in diabetes and their emerging cardiovascular actions have been a major recent research focus. In addition to GLP-1 receptor activation, the metabolically-inactive breakdown product, GLP-1(9-36)amide, also appears to exert notable cardiovascular effects, including protection against acute cardiac ischa...