A series of 1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one-containing Schiff bases were synthesized, characterized and screened for their antibacterial activities. The structures of the synthesized compounds were established by spectroscopic (FT-IR, ¹H-NMR, ¹³C-NMR, MS) and elemental analyses. The anti-bacterial activities (with MIC values) of compounds were evaluated. The anti-bacterial sc...

The title compound, C(17)H(12)BrClN(2)O, was synthesized by oxidation of [3-(4-bromo-phen-yl)-1-(4-chloro-benz-yl)-1H-pyrazol-5-yl]methanol under mild conditions. The pyrazole ring makes dihedral angles of 3.29 (9) and 74.91 (4)°, respectively, with the bromo-phenyl and chloro-phenyl rings.

In the title compound, C(23)H(17)ClN(4)O(2), the amino H atom forms an intra-molecular hydrogen bond to the exocyclic carbonyl O atom as well as to the O atom of the benzoyl group.

In the title compound, C(18)H(15)ClN(4)O(2)S, the pyrazole ring makes dihedral angles of 67.4 (1) and 12.5 (1)° with the phenyl and 4-hydroxy-phenyl groups, respectively; the two benzene rings are twisted by 60.1 (1)° with respect to each other. The thio-urea NH groups are involved in N-H⋯O and N-H⋯Cl intra-molecular hydrogen bonds. A hydrogen bond between the phenolic OH group and the pyrazole...

In the title compound, C(25)H(22)N(4)O(2), the dihedral angles between the central pyrazole ring and the phenyl and benzene rings are 37.01 (3), 75.58 (7) and 49.67 (8)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) motif. In the crystal, N-H⋯O hydrogen bonds link mol-ecules into a zigzag chain extended along the b axis.

In the crystal structure of the title compound, C(20)H(16)ClN(5), the dihedral angle between the pyrazole ring and the phenyl ring is 54.7 (1)° and that between the pyrazole ring and the chloro-substituted phenyl ring is 72.4 (1)°. The methyl H atoms are disordered over two positions with site occupancy factors of ca 0.7 and 0.3. One amino H is disordered equally over two positions. In the crys...