The title compound, C23H24N4OS, contains a highly asymmetric bifurcated intramolecular hydrogen bond between the hydroxy group and two pyrazole N atoms. The compound associates into centrosymmetric dimers in the crystal through two unique C-H...pi interactions, which are in turn linked into a (6,3)-network through an additional intermolecular C-H...N hydrogen bond.

In the Schiff base mol-ecule of the title compound, C(14)H(11)ClN(2)O(3)·2H(2)O, the benzene rings form a dihedral angle of 20.6 (1)°. The water molecules of crystallization are involved in the formation of a three-dimensional hydrogen-bonding network via O-H⋯O and N-H⋯O hydrogen bonds.

In the crystal structure of the title compound, C(26)H(27)NO(3), a one-dimensional network of C-H⋯O hydrogen bonds and π-ring inter-actions is responsible for crystal stabilization. Inter-molecular hydrogen bonds and C-H⋯ π inter-actions produce R(2) (2)(10), R(4) (4)(27) and R(4) (4)(29) rings.

In the title compound, C(13)H(16)O(5), one of the three hy-droxy groups is involved in intra-molecular O-H⋯O hydrogen bonds. The other two hy-droxy groups contribute to the three-dimensional hydrogen-bonding network, which consolidates the crystal packing.

The benzohydrazide mol-ecule of the title compound, C(14)H(11)N(3)O(7)·H(2)O, is planar (r.m.s. deviation = 0.068 Å). The benzohydrazide mol-ecule and the uncoordinated water mol-ecule inter-act through O-H⋯O hydrogen bonds; these together with O-H⋯N and N-H⋯O hydrogen bonds form a three-dimensional network.

The title molecular salt, C(11)H(17)ClNO(+)·C(7)H(5)O(3) (-), was obtained by the reaction of racemic clorprenaline and 4-hy-droxy-benzoic acid. In the crystal, the components are connected by O-H⋯O and N-H⋯O hydrogen bonds, resulting in a two-dimensional hydrogen-bonded network.

The amide bond in the title compound {systematic name: 3-[(2,4,6-trimethyl-phen-yl)amino-carbon-yl]propionic acid}, C(13)H(17)NO(3), has a trans conformation. In the crystal, two mol-ecules form a centrosymmetric dimer connected by pairs of O-H⋯O hydrogen bonds. Inter-molecular N-H⋯O hydrogen bonds link the dimers into a three dimensional network.

In the title compound, C22H19NO3S, the terminal phenyl and methyl-phenyl rings are twisted by 37.35 (12) and 49.08 (13)°, respectively, to the central benzene ring. In the crystal, mol-ecules are linked by classical N-H⋯O hydrogen bonds and weak C-H⋯O hydrogen bonds into a three-dimensional supra-molecular network.

In the title compound, C(16)H(16)N(2)O(3)S(6), the two five-membered rings form a dihedral angle of 7.86 (9)°. Weak C-H⋯N hydrogen bonds link the mol-ecules to form a chain along c; the chains are further connected by weak C-H⋯O hydrogen bonds to form a three-dimensional supra-molecular network.

The mol-ecular conformation of the title compound, C14H18N2O3S2, is stabilized by intra-molecular N-H⋯N and C-H⋯O hydrogen bonds. The crystal packing is characterized by a series of C-H⋯O hydrogen bonds, resulting in a three-dimensional network.