In the title moleclue, C(19)H(21)NO, the 4-piperidone ring adopts a chair conformation in which the two benzene rings and the methyl group attached to C atoms all have equatorial orientations. In the crystal structure, centrosymmetric dimers are formed through weak inter-molecular C-H⋯O hydrogen bonds [the dihedral angle between the aromatic rings is 58.51 (5)°].

The title Schiff base compound, C(22)H(24)IN(3)O(2), adopts an E configuration about the central C=N bond. The pyrazolone ring makes a dihedral angle of 49.68 (10)° with its attached phenyl ring. The phenolate plane makes dihedral angles of 16.78 (9) and 50.54 (9)°, respectively, with the pyrazolone ring and the terminal phenyl ring. An intra-molecular C-H⋯O hydrogen bond generates an S(6) ring...

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 title compound, C(16)H(28)N(2)O(3)S, is dimerized by inversion symmetry-related inter-molecular O-H⋯N hydrogen bonding, forming an R(2) (2)(16) motif. The dimers are also linked through inter-molecular C-H⋯O hydrogen bonding. The compound is chiral with a stereogenic centre located in the thia-zole ring, but in the crystal structure it forms a racemate. The thia-zole ring has an envelope co...