To synthesize 4-chloro-5-methoxy-2-(b-trifluoroethyl)-3(2H)-pyridazinone (4), the reactions of 4-chloro-5-methoxy-3(2H)-pyridazinone (5) with RCH(2)CF(3)(R = I, TsO, MsO, TfO) in different solvents were studied. It was found that methyl group migration took place during this reaction. An oxonium salt 9 was suggested as the active intermediate for the formation of the byproduct 4-chloro-5-methox...

Abbreviations: Pyrazon, 5-amino-4-chloro-2-phenyl-3 (2H) pyridazinone; o-methyl-pyrazon, 5-amino-4-chloro-2(2-methylphenyl)-3(2H)-pyridazinone; m-methyl-pyrazon, 5-aminoj4-chloro-2(3-methylphenyl) 43 (2H) -pyridazinone; p-methyl-pyrazon, 5-amino-4-chloro-2(4-methylphenyl) -3 (2H) pyridazinone. Requests for reprints should be sent to Prof. Dr. F. Lingens, Institut für Mikrobiologie und Molekular...

In this work, some 2-nonsubstituted/2-methyl-/2-(2-acetyloxyethyl)-6-[4-(substituted pyrrol-1-yl)phenyl]-4,5-dihydro-3(2H)-pyridazinone, derivatives and 2-nonsubstituted/2-methyl- 4-[4-(substituted pyrrol-1-yl)phenyl]-1(2H)-phthalazinone derivatives were synthesised by reacting hexan-2,5-dion or 1-aryl-3-carbethoxypent-1,4-diones with corresponding 2-substituted/nonsubstituted 6-(4'-aminophenyl...

In the title compound, C21H24N2O2Si, the carbonyl group of the heterocyclic ring and the O atom of the silyl ether group are placed toward opposite sides and the tert-butyl and pyridazinone moieties are anti-oriented across the Si-O bond [torsion angle = -168.44 (19)°]. In the crystal, mol-ecules are assembled into inversion dimers through co-operative N-H⋯O hydrogen bonds between the NH groups...

A series of pyridazinone derivatives (19-34) were synthesized with an aim to synthesize safer anti-inflammatory agents. The compounds were evaluated for their anti-inflammatory, analgesic, ulcerogenic and lipid peroxidation (LPO) actions. The percentage inhibition in edema at different time intervals indicated that compounds 20, 26, 28 and 34 exhibited good anti-inflammatory potential, comparab...

Pyridazine nucleus exhibited immense pharmacological activities. Pyridazine nucleus is present in various compounds that possess remarkable pharmacological activities. Various pyridazinone compounds have antitumor activity. Some of them pyridazinone derivatives bearing different moieties were exhibited excellent anticancer activity toward human cancer cell lines. They showed remarkable activity...

In the recent years there has been an increased interest in the pyridazinone ring system. Many investigations indicated that the presence of at least one aryl group, one or two electron donor atoms and/or an NH group in a special spatial arrangement is necessary for anticonvulsant activity. Many investigations indicated that the presence of at least one aryl group, one or two electron donor ato...

The title mol-ecule, C19H18N4O2 {systematic name: (RS)-6-[2-(4-meth-oxy-phen-yl)-1H-benzimidazol-5-yl]-5-methyl-4,5-di-hydro-pyridazin-3(2H)-one}, adopts an extended conformation. The dihedral angles between the central benzimidazole ring sytem and the pendant meth-oxy-phenyl and pyridazinone residues are 1.41 (18) and 9.7 (3)°, respectively. In the crystal, N-H⋯N hydrogen bonds link the imadaz...

A series of structurally varied derivatives of 3(2H)-pyridazinone were tested for their analgesic and anti-inflammatory activity by using different test models. The analgesic and anti-inflammatory activity of the compounds were found to be significant as compare with reference drugs. Some of the 3(2H)-pyridazinone derivatives are having analgesic and anti-inflammatory activities. Pyridazine der...

Reaction of 4-anthracen-9-yl-4-oxo-but-2-enoic acid (1) with indole gave the corresponding butanoic acid 2. Cyclocondensation of 2 with hydrazine hydrate, phenyl hydrazine, semicarbazide and thiosemicarbazide gave the pyridazinone derivatives 3a-d. Reaction of 3a with POCl(3) for 30 min gave the chloropyridazine derivative 4a, which was used to prepare the corresponding carbohydrate hydrazone d...