Molecular Structure, Hirshfeld Surface Analysis, Optical and Electrochemical Studies of Stable Solid Diazonium Salt of p-Sulphophenyl-3-methyl-5-pyrazolone

The title compound is a new pyrazolone derivative which was synthesized starting from p-sulphophenyl-3-methyl-5-pyrazolone (1) by nitrosation at low temperature to afford the corresponding p-sulphophenyl-3-methyl-4-nitroso-5-pyrazolone which can exist both in nitroso (2a) and oxime tautomeric forms (2b). Reduction of the latter using zinc with hydrochloric acid furnished the 4-amino-p-sulphophenyl-3-methyl-5-pyrazolone (3). The diazotization of (3) under careful control of temperature and pH afforded the p-Sulphophenyl − 3-methyl-5-pyrazolone diazonium salt (4) which was re-crystallized from acidified ethanol to afford crystal suitable for X-ray studies. UV-visible spectrum and cyclic voltammetric studies were also carried out indicating λmax at 420 nm and HOMO-LUMMO energy gap was also calculated (Eg) of 2.95 eV. The molecular and crystal structures of the compound were clarified by single crystal X-ray diffraction indicated that it crystallizes as the sodium salt in the triclinic space group P -1, with the 4-azo-pyrazolone and the sulphophenyl groups being nearly coplanar. To get an insight to the intermolecular interactions in the crystal a Hirshfeld surface analysis was also carried out.

Synthesis and Pharmacological Activity of Some Pyrazolone Derivatives

A sequence of novel pyrazolone derivative was produced by the reaction of 2, 4-dinitrophenyl hydrazine (0.1 mol) and ethyl acetoacetate with benzaldehydes followed by hydrazine hydrate and finally treated with secondary amine and formaldehyde and the synthesized compounds were characterized by their physical properties (M.P and TLC) and UV, IR, 1HNMR, Mass spectroscopic studies respectively. The entire synthesized complex was tested for their anthelmintic, antimicrobial and haemostatic activity against gram-positive and gram-negative strains of bacteria and Eudrilus eugenia and human venous blood. The antimicrobial activity of synthesized pyrazolone derivatives was assessed by agar cup method. All the synthesized complexes were screened for the antimicrobial, athelmintic and haemostatic activity against some gram (+ve), Gram(-ve) organisms, Eudrilus eugenia and human venous blood. The complexes exhibited reasonable to upright activity when compared with the standard one.

Cadmium(ii) complexes with a 4-acyl pyrazolone derivative and co-ligands: crystal structures and antitumor activity

The antitumor activity of three mononuclear cadmium(ii) complexes and an apoptosis assay of complex 3 were investigated.