Search results for "Pyrazole"
showing 10 items of 315 documents
ChemInform Abstract: Synthesis and Pharmacological Evaluation of 1-Methyl-5- [substituted-4(3H)-oxo-1,2,3-benzotriazin-3-yl]-1H-pyrazole-4-acetic Aci…
2010
Abstract Several new 1-methyl-5-[substituted-4-oxo-1,2,3-benzotriazin-3-yl]-1H-pyrazole-4-acetic acids and their ethyl ester derivatives were prepared. The compounds were tested for analgesic and antiinflammatory activities, acute toxicity, ulcerogenic effect, and as in vitro inhibitors of 3α-hydroxysteroid dehydrogenase (3α-HSD), since it is claimed that the inhibition of such an enzyme predicts in vivo antiinflammatory activity. Some compounds were more active than phenylbutazone in the phenylbenzoquinone and acetic acid peritonitis tests, and equiactive to the same drug in the carrageenin paw edema test. All the compounds inhibited the 3α-HSD, but no correlation was observed with the paw…
CuIIand ZnIICoordination Chemistry of Pyrazole‐Containing Polyamine Receptors − Influence of the Hydrocarbon Side Chain Length on the Metal Coordinat…
2004
The synthesis of a new macrocyclic receptor (L 4 ) containing two 3,5-dimethylpyrazole units connected by dipropylenetriamine bridges is reported for the first time; pH-metric titrations indicate that L 4 shows six protonation steps in the pH range 2-11. In the absence of metal ions, the pyrazole moieties are not involved in acid-base processes in this pH range. Addition of Cu I I and Zn I I results in deprotonation of the pyrazole moieties which act as bis(monodentate) η 1 :η 1 ligands. This induced deprotonation occurs at higher pH values than in the complexes of the analogous ligand containing diethylenetriamine bridges (L 1 ). The crystal structures of [Cu 2 (H - 2 L 4 )](ClO 4 ) 2 and …
5-Amino-1-phenyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid
2009
In the title compound, C11H8F3N3O2, there are two molecules in the asymmetric unit wherein the phenyl rings make dihedral angles of 65.3 (2) and 85.6 (2)° with the pyrazole rings. In the crystal, pairs of molecules are held together by O—H...O hydrogen bonds between the carboxyl groups, forming a centrosymmetric dimer with an R22(8) motif. Intramolecular N—H...O interactions are also present.
Discrete and 1D coordination polymeric chloro-bridged copper(II) dimers exhibiting ferro- and antiferromagnetic exchange coupling: Magneto-structural…
2009
The synthesis and characterization of two 1D coordination polymers [Cu 2 (MHL)Cl 2 ][ClO 4 ] 2 · CH 3 CN · THF ( 2 · CH 3 CN · THF) and [Cu 2 (MPyPz)Cl 2 ][ClO 4 ] 2 · CH 3 CN ( 3 · CH 3 CN), having repetitive { Cu 2 II ( μ -Cl ) 2 } units, of m -xylyl-based ligands with terminal tridentate (2-pyridyl)alkylamine (MHL = α,α′-bis[ N -(2-pyridylethyl)- N -(2-pyridylmethyl)amino]- m -xylene) and (2-pyridyl)alkylamine/pyrazole (MPyPz = α,α′-bis[ N -(2-pyridylethyl)- N -(pyrazol-1-ylmethyl)amino]- m -xylene) coordination have been accomplished. X-ray crystallographic studies reveal that the copper(II) centers in the recently reported dichloro-bridged discrete { Cu 2 II ( μ -Cl ) 2 } complex […
Design, synthesis and antiproliferative activity of methyl 4-Iodo-1-β-D-ribofuranosyl-pyrazole-3-carboxylate and related compounds
1996
Abstract In a SAR study on azole-related nucleosides we have designed some pyrazole-nucleoside analogs characterised, for the first time, by a carboxylic ester moiety. 4-Iodo-1-β-D-ribofuranosyl-pyrazole-3-carboxylate showed a wide spectrum of antiproliferative activity and a particularly low cytotoxicity against resting PBL, being, unlike the other azole nucleosides, more active than the corresponding primary amide.
NonclassicalPschorr andSandmeyer Reactions in Pyrazole Series
2005
The diazonium salt derived from 4-amino-N,1,3-trimethyl-N-(3-methyl-1-phenyl-1H-pyrazol-5-yl)-1H-pyrazole-5-carboxamide (14) was reacted with a mixture of CuSO4 and NaCl, with ascorbic acid as an initiator to afford the planar derivative 4,6-dihydro-1,4,6,8-tetramethyl-3-phenyldipyrazolo[3,4-b:4′,3′-d]pyridin-5(3H)-one (16) and its unexpected isomer 4,6-dihydro-3,4,6,8-tetramethyl-1-phenyldipyrazolo[4,3-b:4′,3′-d]pyridin-5(1H)-one (17), as well as the epimers (3S,4S)- (or (3S,4R)-) and (3S,4R)- (or (3S,4S)-) 4-chloro-2,4-dihydro-1′,3′,5,5′-tetramethyl-2-phenylspiro[pyrazole-3,4′(1′H)-pyrrolo[3,4-c]pyrazol]-6′(5′H)-one (18a and b, respectively). Epimers 18a and b were converted under basic c…
Synthesis of 4-amino-5-fluoropyrimidines and 5-amino-4-fluoropyrazoles from a β-fluoroenolate salt
2020
A synthesis of fluorinated pyrimidines under mild conditions from amidine hydrochlorides and the recently described potassium 2-cyano-2-fluoroethenolate was developed. A broad substrate scope was tested and mostly excellent yields were obtained. The synthesis of fluorinated aminopyrazoles from the same fluorinated precursor could be demonstrated but proceeded with lower efficiency.
Cu(II), Ni(II) and Zn(II) mononuclear building blocks based on new polynucleating azomethine ligand : Synthesis and characterization
2017
Five new mononuclear complexes formed by the polynucleating ligand 2-[1-(3,5-dimethyl)pyrazolyl]-2-hydroxyimino-N′-[1-(2-pyridyl)ethylidene]acetohydrazide (HL): [Ni(L)(HL)]ClO4·2CH3OH (1), [Ni(L)2]·CH3OH (2), [Zn(L)(HL)]ClO4·2CH3OH (3), [Zn(L)2]·CH3OH (4) and [Cu(L)2]·CH3OH (5) were synthesized and characterized by elemental analysis, mass-spectrometry, IR-spectroscopy and X-ray analysis. The complexes reveal distorted octahedral N4O2 coordination arrangement formed by both protonated and deprotonated (1, 3) or two deprotonated ligand molecules (2, 4, 5). The presence of non-coordinated oxime and pyrazole groups resulted in the formation of extensive systems of hydrogen bonds in the crystal…
Susceptibility of Methyl 3-Amino-1H-pyrazole-5-carboxylate to Acylation
2009
Abstract In the search for a new method of synthesis of hybrid peptides with aminopyrazole carboxylic acid, we tried to force selective acylation at the aromatic amino group instead of at the ring nitrogen atom with fairly gentle acylating agents. The acylating agents used were acid anhydrides: acetic anhydride, tert-butyl pyrocarbonate, and 2-(2-methoxyethoxy)ethoxyacetic acid/dicyclohexylcarbodiimide. We succceded in acylation at this amino group with almost none at the ring nitrogen atom. Sometimes, however, acylation in small quantities at the ring nitrogen atom was observed as a by-product. To remove this by-product, imidazole was used. Thus, we were able to obtain the hybrid peptides …
Studies on the synthesis of heterocyclic compounds. Part IV. Further investigation of the pschorr reaction with some pyrazole derivatives
1980
Thermal decomposition of the diazonium sulfate derived from N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-aminobenzamide afforded products formulated as 1-phenyl-3-methyl[2]benzopyrano[4,3-c]pyrazol-5-one (yield 10%), 1,4-dimethyl-3-phenylpyrazolo[3,4-c]isoquinolin-5-one (yield 10%), N-methyl-(1-phenyl-3-methylpyrazol-5-yl)-2-hydroxybenzamide (yield 8%) and 4′-hydroxy-2,3′-dimethyl-1′-phenylspiro[isoindoline-1,5′-[2]-pyrazolin]-3-one (yield 20%). Decomposition of the diazonium sulfate derived from N-methyl-(1,3-diphenylpyrazol-5-yl)-2-aminobenzamide gave products formulated as 7,9-dimethyldibenzo[e,g]pyrazolo[1,5-a][1,3]-diazocin-10-(9H)one (yield 8%), 4-methyl-1,3-diphenylpyrazolo[3,4-c]isoqu…