In the structure of the title nicotino-nitrile derivative, C19H15N3O, the pyridine ring makes dihedral angles of 11.50 (7) and 43.36 (8)° with the 4-amino-phenyl and phenyl rings, respectively, and the dihedral angle between the phenyl rings is 36.28°. In the crystal, mol-ecules are linked by N-H⋯N hydrogen bonds into wave-like sheets parallel to (10-2). These sheets are stacked by π-π inter-actions between the 4-amino-phenyl rings of adjacent sheets, with centroid-centroid distances of 3.7499 (9) Å. C-H⋯π inter-actions are also present.
The asymmetric unit of the title compound, C18H18ClN3OS·C2H5OH, comprises a pyrazoline derivative and an ethanol solvent mol-ecule. In the mol-ecule of the pyrazoline derivative, the pyrazole ring adopts an envelope conformation with the C atom bearing the eth-oxy-phenyl substituent as the flap. The dihedral angle between the benzene rings is 74.22 (7)°. The eth-oxy group is coplanar with the attached benzene ring [C-O-C-Cmeth-yl = 175.50 (11)° and r.m.s. deviation = 0.0459 (1) Å for the nine non-H atoms]. In the crystal, the pyrazoline mol-ecules are linked by N-H⋯Oeth-oxy hydrogen bonds into chains along the c axis and are further linked with the solvent ethanol mol-ecules by N-H⋯Oethanol and Oethanol-H⋯S hydrogen bonds. C-H⋯π inter-actions are also present.