In the isoquinoline ring system of the title mol-ecule, C(19)H(24)N(2)O(6), the N-heterocyclic ring is in a half-boat conformation. The mol-ecular structure is stabilized by an intra-molecular O-H⋯O hydrogen bond, which generates an S(7) ring motif. In the crystal, mol-ecules are linked via inter-molecular bifurcated N-H⋯(O,O) and weak C-H⋯O hydrogen bonds into a three-dimensional network.

The title indan-1-one derivative, C(16)H(11)BrO, is planar, the r.m.s. deviation for all 18 non-H atoms being 0.071 Å. The configuration about the C=C bond [1.337 (5) Å] is E. In the crystal, supra-molecular layers in the ab plane are formed by C-H⋯O inter-actions, involving the bifurcated carbonyl O atom, as well as C-H⋯π inter-actions. The studied crystal was an inversion twin.

(1)H NMR chemical shifts have been obtained in the solvents deuterochloroform and dimethyl sulfoxide. The difference in the chemical shifts of an OH or NH group in these two solvents, Δδ = δ(DMSO) - δ(CDCl3), can be converted into the hydrogen bond acidity, A, of the group using the equation A = 0.0065 + 0.133Δδ. The NMR A value, ANMR, can be used as a quantitative assessment of intramolecular ...

In the title compound, C11H11N3O3S·3H2O, the non-H atoms of the main mol-ecule are approximately planar, with an r.m.s. deviation of 0.030 Å. There is a bifurcated intra-molecular N-H⋯(O,S) hydrogen bond present forming S(6) and S(5) ring motifs. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the molecules into a three-dimensional network.

In the title compound, C(10)H(12)N(2)O(3)·H(2)O, the Schiff base mol-ecule is approximately planar [within 0.189 (1) Å]. The inter-planar angle between the benzene and acetohydrazide planes is 8.50 (10)°. In the crystal, mol-ecules are linked into a three-dimensional network by strong and weak O-H⋯O and strong N-H⋯O hydrogen bonds. The hydr-oxy H atom deviates from the 4-hydr-oxy-3-methoxy-phen...

In the crystal structure of the title salt, C(8)H(8)NO(2) (+)·I(-), the cations and anions are linked by bifurcated N-H⋯(O,I) hydrogen bonds. A near-linear O-H⋯I hydrogen bond also exists between the cation and anion, resulting in a two-dimensional network. In the cation, the carboxyl group is twisted with respect to the pyridine ring at a dihedral angle of 15.34 (17)°.

The title compound, C15H22O3, crystallizes with two independent mol-ecules in the asymmetric unit. In each mol-ecule, one hy-droxy group (at position 2) is involved in an intra-molecular O-H⋯O hydrogen bond, and another one (at position 3) exhibits bifurcated hydrogen-bonding being involved in intra- and inter-molecular O-H⋯O inter-actions. In the crystal, O-H⋯O hydrogen bonds link alternating ...

In the title compound, C(20)H(13)ClN(2)O(2)S, the chloro-phenyl, phenyl and thienoyl rings are oriented at dihedral angles 17.84 (7), 53.13 (8) and 34.03 (8)°, respectively, to the central pyrazole ring. An intra-molecular O-H⋯O hydrogen bond occurs. In the crystal, pairs of bifurcated O-H⋯O hydrogen bonds link mol-ecules into inversion dimers with R(2) (2)(12) graph-set motifs.

Crystals of the title compound, C(12)H(8)N(2)·C(7)H(8)O(2), were obtained during cocrystallization experiments of a compound with two hydrogen-bond donors (2-hydroxy-benzyl alcohol) with another compound containing two hydrogen-bond acceptors (phenanthroline). Unexpectedly, the two mol-ecules do not form dimers with two O-H⋯N hydrogen bonds connecting the two mol-ecules. However, one of the hyd...

The title mol-ecule, C(13)H(8)N(4), is is essentially planar [r.m.s. deviation for all non-H atoms = 0.025 (3) Å]. In the crystal, mol-ecules are connected through one weak bifurcated N-H⋯(N,N) hydrogen bond and three π-π stacking inter-actions between pyridine and imidazole rings [centroid-centroid distance = 3.631 (8) Å] and between pyridine and benzene rings [centroid-centroid distances = 3....