4-[(E)-(4-Diethyl-amino-2-hy-droxy-benzyl-idene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one.

In the title compound, C(22)H(26)N(4)O(2), the phenyl ring and hy-droxy-benzene group are twisted with respect to the central pyrazolone ring, making dihedral angles of 54.05 (5) and 21.80 (6)°, respectively. One of the ethyl groups is disordered over two positions with site occupancies of 0.872 (6) and 0.128 (6). The mol-ecular structure features short intra-molecular O-H⋯N and C-H⋯O contacts. The crystal packing exhibits weak inter-molecular C-H⋯O and C-H⋯π inter-actions.

2,4-Diiodo-6-{[4-(morpholin-4-yl)phenyl]iminomethyl}phenol.

In the title compound, C(17)H(16)I(2)N(2)O(2), the two aromatic rings are almost coplanar [dihedral angle 2.57 (15)°]. The morpholine ring adopts a chair conformation. The mol-ecular structure is stabilized by an O-H⋯N hydrogen bond and the crystal packing exhibits weak inter-molecular C-H⋯O and π-π [centroid-to-centroid distances 3.663 (3)-4.073 (3) Å] inter-actions.

5-Meth-oxy-2-{[4-(morpholin-4-yl)phen-yl]imino-meth-yl}phenol.

In the title compound, C(18)H(20)N(2)O(3), the dihedral angle between the two aromatic rings is 33.66 (6)°. The morpholine ring adopts a chair conformation. The mol-ecular structure is stabilized by an intra-molecular O-H⋯N hydrogen bond. In the crystal, mol-ecules are linked via weak inter-molecular C-H⋯O and C-H⋯π inter-actions.

2-Bromo-4-chloro-6-{(E)-[4-(diethyl-amino)-phen-yl]imino-meth-yl}phenol.

In the title compound, C(17)H(18)BrClN(2)O, the dihedral angle between the aromatic rings is 3.0 (1)°. The methyl-ethanamine group assumes an extended conformation. An intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. The crystal packing is stabilized by C-H⋯π and π-π [centroid-centroid distances = 3.691 (1) and 3.632 (1) Å] inter-actions.