The crystal structure of the title compound, C(17)H(24)N(2)O(5), was determined in the course of our studies on the preparation of two families of pseudopeptides, viz. hydrazino- and N-amino- peptides. The most significant inter-action in the crystal structure is a bifurcated inter-molecular N-H⋯O hydrogen bond.

In the title mol-ecular salt, C12H24N(+)·NO3 (-), the cyclohexyl rings adopt chair conformations with the exocyclic C-N bonds in equatorial orientations. In the crystal, a bifurcated N-H⋯(O,O) hydrogen bond links the cation to the anion; the ion pairs are linked via C-H⋯O hydrogen bonds, forming layers in the ac plane.

In the present work, DFT calculations are employed to obtain the optimized structures of 4- acyl pyrazolone tautomers (19 tautomers) using B3LYP/6-311++G** calculations. In addition, molecular parameters, IR frequencies and relative energies are extracted for all tautomers. The existence of aromatic ring, keto tautomer (versus enol tautomer), N-H bond (versus C-H bond) and C=N double bond (vers...

There are three independent mol-ecules in the asymmetric unit of the title compound, C(19)H(16)N(2)O(3), in which the dihedral angles between the naphthalene ring system and the benzene ring are 7.52 (16), 18.15 (18), and 13.9 (2)°. All the mol-ecules exist in the trans configuration with respect to the methyl-idene units. In each mol-ecule there is one O-H⋯N and one N-H⋯O intra-molecular hydro...

The title Schiff base compound, C(15)H(13)ClN(2)O(3), was prepared by the reaction of equimolar quanti-ties of 5-chloro-2-hy-droxy-benzaldehyde with 2-meth-oxy-benzohydrazide in a methanol solution. The dihedral angle between the two benzene rings is 20.6 (3)°. An intra-molecular O-H⋯N hydrogen bond may influence the mol-ecular conformation. In the crystal structure, mol-ecules form chains alon...

The structural, vibrational, and energetic properties of adducts of alkanes and strong cationic proton donors were studied with composite ab initio calculations. Hydrogen bonding in D-H(+)...H-alkyl adducts contributes to a significant degree to the interactions between the two components, which is substantiated by NBO and AIM results. The hydrogen bonds manifest themselves in the same manner a...

The title compound, C(19)H(19)ClO(5), is a chloro derivative of a biologically significant chalcone family. The mean plane of the two substituted benzene rings are twisted by 55.33 (8)° with respect to each other. An intra-molecular C-H⋯Cl hydrogen bond generates an S(5) graph-set motif. In the crystal, a bifurcated O-H⋯(O,O) hydrogen bond leads to an R(1) (2)(5) graph-set motif and to the form...

The title compound, C(16)H(16)BrNO(3), adopts an E configuration with respect to the imine C=N bond. The two benzene rings are twisted with respect to each other at an angle of 38.3 (1)°. In the crystal structure, mol-ecules are connected by weak bifurcated C-H⋯(O, O) hydrogen bonds, forming a helical chain along the b axis.

In the title compound, C(21)H(21)N(3)O(2), the pyridine rings and the benzene ring lie in a propeller arrangement around the central tertiary amine N atom. The dihedral angles formed by the benzene ring with the pyridine rings are 61.0 (3) and 49.6 (3)°, while the dihedral angle between the pyridine rings is 69.7 (3)°. The mol-ecular conformation is stabilized by intramolecular bifurcated O-H⋯N...

In the title compound, C(15)H(15)N(3)OS, the thio-urea group is stabilized by an intra-molecular hydrogen bond between the carbonyl O atom and the thio-amide group. A C-H⋯N intramolecular hydrogen bond is also present. Mol-ecules are linked by inter-molecular N-H⋯O and C-H⋯S hydrogen bonds.