In the title compound, C(20)H(26)N(2)OS, four non-H atoms of the thio-urea unit are approximately planar (r.m.s. deviation = 0.005 Å); the phenyl and benzene rings are twisted out of this plane by 28.55 (7) and 60.00 (7)°, respectively. An intra-molecular N-H⋯O hydrogen bond occurs. The hy-droxy group is hydrogen bonded to the double-bond S atom of an inversion-related mol-ecule, generating a h...

It is shown that the mutagen base analogue 2-aminopurine is hydrogen-bonded at its 1-ring position when annealed with cytosine in DNA. The presence of stably hydrogen-bonded regions proximal to the 2-aminopurine-cytosine base mispair is a prerequisite for the occurrence of two hydrogen bonds coupling the bases at their 1-3- and 2-2-positions. We consider the possibility that, in the resulting h...

The title ionic compound, C(2)H(10)N(2) (2+)·2Cl(-), crystallizes with a center of symmetry within the cation. Each of the positively charged ammonium ends of the mol-ecule is trigonally hydrogen bonded to three different chloride counter-ions, while each of the chloride ions is trigonally hydrogen bonded to three different ethyl-enediammonium cations. The hydrogen-bonding network leads to stab...

Hydrogen-Bonded Frameworks. A hydrogen-bonded framework that was predicted to have 3-D porosity has been discovered experimentally by Anna G. Slater, John W. Ward, Marc A. Little, Andrew I. Cooper et al. in their Research Article (e202303167). It is one of the most porous frameworks synthesized date.

A redetermination of the crystal structure of the title compound, C(6)H(16)N(2) (2+)·2Cl(-), was undertaken. All atomic coordinates including those of the H atoms were refined freely. The cation is located on a centre of symmetry. Important for the crystal structure are wavy hydrogen-bonded layers that are formed by ammonium groups and chloride anions, giving hydrogen-bonded rings.

This contribution reports solution-phase structural studies of oligomers of a family of peptides derived from the β-amyloid peptide (Aβ). We had previously reported the X-ray crystallographic structures of the oligomers and oligomer assemblies formed in the solid state by a macrocyclic β-sheet peptide containing the Aβ(15-23) nonapeptide. In the current study, we set out to determine its assemb...

The formation of hydrogen bonded complexes between nucleic acid bases and acetamide has been studied by nuclear magnetic resonance in CDC13 at different temperatures. Pairs of hydrogen bonds are formed when acetamide binds to nucleic acid bases. Thermodynamic parameters have been computed and compared to those obtained for the association of carboxylic acids with nucleic acid bases. The role of...

In the title compound, C(5)H(8)N(3) (+)·Cl(-), the cation and the anion lie on a mirror plane and are hydrogen bonded in a three-dimensional network via the H atoms of the two hydrazine N atoms. The pyridine N atom is protonated and hydrogen bonded to the terminal hydrazine N atom.

The title mol-ecule, C(30)H(28)N(2)O(4), has crystallographic twofold rotation symmetry, with the pyrrole planes forming a dihedral angle of 40.49 (4)°. The pyrrole N-H donor and adjacent ester carbonyl acceptor form R(2) (2)(10) hydrogen-bonded rings about inversion centers, leading to chains of hydrogen-bonded mol-ecules along [001].

In molecular dynamics simulations we found that water can form hydrogen-bonded water chains in the interior of carbon nanotubes. Water penetration is sensitive to details of thermodynamic conditions and interaction potentials, resulting in sharp, first-order like transitions between filled and empty states. Under wetting conditions, water molecules are transported efficiently through nanotubes....