Considerable amount of research has been carried out in the field of pyrazolone derivatives due to their diverse biological, pharmacological and chemical properties. The need was felt to synthesize certain 3-methyl-5-pyrazolone derivatives with potent analgesic and anti-inflammatory activity and with lesser side effects as it had been proved of late that the beneficial effects of pyrazolones ou...

The thioredoxin/thioredoxin reductase system (Trx/TrxR) is an attractive drug target because of its involvement in a number of important physiological processes, from DNA synthesis to regulating signal transduction. This study describes the finding of pyrazolone compounds that are active against Staphylococcus aureus. Initially, the project was focused on discovering small molecules that may ha...

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 can exist both in nitroso (2a) and oxime tautomeric forms (2b). Reduction of latter using zinc with hydrochloric acid furnished 4-amino-p-sulphophenyl-3-methyl-5...

A bioassay of 1-phenyl-3-methyl-5-pyrazolone for possible carcinogenicity was conducted using Fischer 344 rats and B6C3F1 mice. 1-Phenyl-3-methyl-5-pyrazolone was administered in the feed, at either of two concentrations, to groups of 49 or 50 male and 50 female animals of each species. The high and low concentrations of 1-phenyl-3-methyl-5-pyrazolone utilized were, respectively, 5,000 and 2,50...

The structures of l-phenyl-3-methyl-pyrazolone-5 and its benzoyl derivatives have been investigated by means of IR, UV, NMR, and mass spectral spectroscopy. 1-Phenyl 3-methyl-pyrazolone-5 is found to exist as a zwitter ion in the solid state, in the 5-keto form in chloroform and dioxane, and in the 5-hydroxy form in pyridine. The 4-benzoyl derivative of l-phenyl-3-methyl-pyrazolone-5 is shown t...

The mean plane of the pyrazolone ring [maximum deviation = 0.054 (1) Å] of the title compound, C(14)H(15)N(3)O(2), is oriented at a dihedral angle of 36.05 (7)° with respect to the phenyl ring. The methyl group is slightly disposed [distance = 0.864 (2) Å] out of the mean plane of the pyrazolone ring to which it is attached.

In the title compound, C(25)H(22)BrN(3)O(5)S, the central benzene ring makes dihedral angles of 4.41 (10), 67.09 (9) and 62.05 (10)°, respectively, with the pyrazolone, bromo-benzene and terminal phenyl rings. The dihedral angle between the pyrazolone and phenyl rings is 57.75 (11)°. In the crystal, two pairs of C-H⋯O hydrogen bonds link the mol-ecules into inversion dimers. A weak intra-molecu...

Structural and electronic factors are crucial to rationalize the different N,O or N,N chelating coordination of pyrazolones containing a pyridine ring. The reactivity proligand 3-phenyl-1-(pyridin-2-yl)-5-pyrazolone (HLpy,ph) with (arene)Ru(II) fragment was explored. Neutral ionic complexes were obtained fully characterized, also by X-ray diffraction, revealing ligand coordinate in an unusual N...

An efficient chiral squaramide-catalysed enantioselective Michael addition of pyrazolin-5-ones to 3-nitro-2H-chromenes for the synthesis of chiral heterocyclic systems containing both chroman and pyrazolone derivatives has been developed. This reaction afforded the desired products in high to excellent yields (up to 98%) with high enantioselectivities (up to 96%) and excellent diastereoselectiv...

In the title compound, C(10)H(16)N(2)O·H(2)O, the cyclo-hexane ring is in a chair conformation and its least-squares plane makes a dihedral angle of 53.68 (5)° with the approximately planar pyrazole ring [maximum deviation = 0.034 (1) Å]. Pairs of inter-molecular N-H⋯O hydrogen bonds form inversion dimers between neighbouring pyrazolone mol-ecules, generating R(2) (2)(8) ring motifs. The pyrazo...