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At least 19 recordsLinked to original sources
PubMed1991

3,5-Diphenyl-1H-pyrazole derivatives. VIII. N-substituted 3-(4-hydroxy-3,5-diphenyl-1H-pyrazol-1-yl)-propanamides, -propanamines and 2-(4-hydroxy-3,5-diphenyl-1H-pyrazol-1-yl)ethanamines with platelet antiaggregating, hypotensive, antiarrhythmic and other activities.

The synthesis of N,N-disubstituted 3-(4-hydroxy-3,5-diphenyl-1H-pyrazol-1-yl)-propanamides and -propanamines, starting from 4-benzoyloxy-3,5-diphenyl-1H-pyrazole, and of N-substituted 2-(4-hydroxy-3,5-diphenyl-1H-pyrazol-1-yl)ethanamines, starting from 4-acetoxy-1-(2-hydroxyethyl)-3,5-diphenyl-1H-pyrazole, is described. Some of the above compounds showed a platelet antiaggregating activity in vitro superior or comparable to that of acetylsalicylic acid, as well as moderate hypotensive, antiarrhythmic, local anesthetic, sedative and antiinflammatory activities in rats and mice.

Anesthetics↗
PubMed1990

3,5-Diphenyl-1H-pyrazole derivatives. IV--N,N-disubstituted 3-(3,5-diphenyl-1H-pyrazol-1-yl)propanamides and 3-(3,5-diphenyl-1H-pyrazol-1-yl)propanamines with sedative, platelet antiaggregating and local anesthetic activities.

The synthesis of N,N-disubstituted 3-(3,5-diphenyl-1H-pyrazol-1-yl)propanamides 2 a-d and 3-(3,5-diphenyl-1H-pyrazol-1-yl)propanamines 3 a-d starting from 3-(3,5-diphenyl-1H-pyrazol-1-yl)propanoic acid is described. Some of the above compounds showed considerable sedative and local anesthetic activities in mice, as well as a remarkable platelet antiaggregating activity in vitro. Moreover, the above compounds usually exhibited moderate analgesic and antiinflammatory activities in mice and rats, respectively.

Amides↗
PubMed1990

3,5-Diphenyl-1H-pyrazole derivatives. V--1-Acetyl-4-hydroxy-3,5-diphenyl-2-pyrazoline esters, 4-hydroxy-3,5-diphenyl-1H-pyrazole esters and N-substituted 4-(3-amino-2-hydroxy-1-propoxy)-1-methyl-3,5-diphenyl-1H-pyrazoles with antiarrhythmic, sedative and platelet antiaggregating activities.

The synthesis of 1-acetyl-4-hydroxy-3,5-diphenyl-2-pyrazoline esters 3, 4-hydroxy-3,5-diphenyl-1H-pyrazole esters 5 and N-substituted 4-(3-amino-2-hydroxy-1-propoxy)-1-methyl-3,5-diphenyl-1H-pyrazoles 7, starting from 4-hydroxy-3,5-diphenyl-2-pyrazoline is described. Some of compounds 3, 5 and 7 showed a considerable antiarrhythmic and sedative activity in rats and mice, respectively, as well as a remarkable in vitro platelet antiaggregating activity. Moreover, the above compounds usually exhibited moderate antihypertensive, local anesthetic, analgesic and antiinflammatory activities in rats and mice.

Analgesics↗
PubMed1990

3,5-Diphenyl-1H-pyrazole derivatives. VI--Esters and 2-dialkylaminoethyl ethers of 1(2-hydroxy-2-phenylethyl)-3,5-diphenyl-1H-pyrazole and N,N-disubstituted 1-(2-amino-2-phenylethyl)-3,5-diphenyl-1H-pyrazoles with depressant and platelet antiaggregating activities.

The syntheses of 1-(2-hydroxy-2-phenylethyl)-3,5-diphenyl-1H-pyrazole 1 by reaction of 2-hydrazino-1-phenylethanol with dibenzoylmethane, of esters 2 and 2-dialkylaminoethyl ethers 3 starting from 1 as sodium salt and acyl chlorides or 2-chloroethyldialkylamines, respectively, as well as of N,N-disubstituted 1-(2-amino-2-phenylethyl)-3,5-diphenyl-1H-pyrazoles 5 by reaction of secondary amines with the tosylate of 1, are described. Some of the above compounds showed a considerable sedative effect in mice and a remarkable platelet antiaggregating activity in vitro, as well as moderate local anesthetic, analgesic and antiinflammatory activities in mice and rats.

Anesthetics, Local↗
PubMed2005

Transition metal complexes with pyrazole-based ligands. XXII. Part XXI: Mészáros Szécsényi, Leovac, Kovacs, Pokol & Jaćimović (2005). Di-mu-thiocyanato-bis[(3,5-dimethyl-1H-pyrazole-1-carboxamidine-kappa2N,N')(thiocyanato-kappaN)copper(II)] and a redetermination of bis(3,5-dimethyl-1H-pyrazole-1-carboxamidine-kappa2N,N')bis(nitrato-kappaO)copper(II).

The title Cu(II) complex, [Cu2(NCS)4(C6H10N4)2], represents the first crystal structure of a polynuclear transition metal complex with the 3,5-dimethyl-1H-pyrazole-1-carboxamidine ligand (HL). It is compared with previously reported crystal structures of metal complexes with the same HL ligand. The molecule contains an eight-membered binuclear Cu2(NCS)2 ring, which is centrosymmetric and in a chair conformation. The Cu atom has a distorted square-pyramidal geometry with a very elongated Cu-S bond of 2.993 (2) A. The crystal structure redetermination of the bis(3,5-dimethyl-1H-pyrazole-1-carboxamidine-kappa(2)N,N')bis(nitrato-kappaO)copper(II)complex, [Cu(NO3)2(C6H10N4)2], and analysis of its hydrogen bonds confirm the significance of the NO3 groups in the formation of a three-dimensional hydrogen-bonding network. Both complexes are centrosymmetric, the inversion centre being located at the mid-point of the Cu...Cu line in (I) and the Cu atom being located at the inversion centre in (II).

Journal Article↗
PubMed1993

3,5-diphenyl-1H-pyrazole derivatives. XI. N-aryl-5(3)-phenyl-4-(3,5- diphenyl-1-pyrazolyl)-3(5)-pyrazole amines, 5-substituted 4,5-dihydro-3-phenyl-4-(3,5-diphenyl-1-pyrazolyl)-1H-pyrazoles and 2,6-disubstituted 1,6-dihydro-4- phenyl-5-(3,5-diphenyl-1-pyrazolyl)pyrimidines with antipyretic, antiinflammatory and other activities.

The synthesis of N-aryl-5(3)-phenyl-4-(3,5-diphenyl-1-pyrazolyl)-3(5)- pyrazoleamines 3 by reaction of some N-aryl-3-oxo-3-phenyl-2-(3,5-diphenyl-1- pyrazolyl)propanecarbothioamides with hydrazine is described. Also prepared were 4,5-dihydro-3-phenyl-4-(3,5-diphenyl-1-pyrazolyl)-1H-pyrazoles 6 and 1,6-dihydro-4-phenyl-5-(3,5-diphenyl-1-pyrazolyl)pyrimidines 7 by reaction of 1-phenyl-2-(3,5-diphenyl-1-pyrazolyl)-2-buten-1-one with hydrazine or guanidine and benzamidine, respectively. Some compounds 3, 6 and 7 showed remarkable antipyretic, antiinflammatory and in vitro platelet antiaggregating activities, as well as weak analgesic, antiarrhythmic, hypotensive and local anesthetic activities in rats and mice.

Anesthetics, Local↗
PubMed1985

Metabolism of the amino acid beta-pyrazol-1-ylalanine and its parent base pyrazole.

beta-Pyrazol-1-yl-DL-alanine, an uncommon amino acid from plants of the Cucurbitaceae, was fed to mice. Although pyrazole is known to affect the liver enzymes UDP-glucose dehydrogenase, UDP-glucuronyl transferase and UDP-glucuronic acid pyrophosphatase, and also depresses their liver glycogen concentrations, beta-pyrazol-1-ylalanine had no such effects. beta-Pyrazol-1-ylalanine could not be detected in the liver of the experimental animals but was present in the urine. No other change in urinary amino acid content was observed. Studies with [14C]-beta-pyrazol-1-yl-DL-alanine showed the administered amino acid was excreted over a 4-day period, 93% of the compound supplied was recovered. Similar recoveries were obtained with the L-enantiomer from cucumber seed. The metabolic inertness of beta-pyrazol-1-ylalanine was also apparent in experiments involving subcutaneous injection of this compound. Administration of pyrazole confirmed an earlier report of resultant increased activity of liver UDP-glucose dehydrogenase and UDP-glucuronyl transferase, and of the depression of activity of liver UDP-glucuronic acid pyrophosphatase. A concomitant 40% decrease in liver glycogen content was seen. The urine contained a novel metabolite, identified as a peptide conjugate of a pyrazole derivative. Mass spectrometry and p.m.r. spectroscopy indicate that this derivative is 3,4,4-trimethyl-5-pyrazolone. The amino acid constituents are aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine and leucine. The urine of mice receiving pyrazole contained less free glycine and alanine than controls. From the results, it is concluded that pyrazole is not a catabolite of dietary beta-pyrazol-1-ylalanine but to the contrary, the amino acid is essentially excreted unchanged. Formation of 3,4,4-trimethyl-5-pyrazolone from pyrazole would imply C-methylation, a process that has not been previously observed in a mammalian detoxication context.

Amino Acids↗
PubMed2001

Estrogen pyrazoles: defining the pyrazole core structure and the orientation of substituents in the ligand binding pocket of the estrogen receptor.

Previously, we reported that certain tetrasubstituted 1,3,5-triaryl-4-alkyl-pyrazoles bind to the estrogen receptor (ER) with high affinity (Fink, B. E.; Mortenson, D. S.; Stauffer, S. R.; Aron, Z. D.; Katzenellenbogen, J. A. Chem. Biol. 1999, 6, 205-219; Stauffer, S. R.; Katzenellenbogen, J. A. J. Comb/. Chem. 2000, 2. 318 329; Stauffer, S. R.: Coletta, C. J.: Sun, J.; Tedesco, R., Katzenellenbogen, B. S.; Katzenellenbogen, J. A. J. Med. Chem. 2000, submitted). To investigate how cyclic permutation of the two nitrogen atoms of a pyrazole might affect ER binding affinity, we prepared a new pyrazole core isomer, namely a 1,3,4-triaryl-5-alkyl-pyrazole (2), to compare it with our original pyrazole (1). We also prepared several peripherally matched core pyrazole isomer sets to investigate whether the two pyrazole series share a common binding orientation. Our efficient, regioselective synthetic route to these pyrazoles relies on the acylation of a hydrazone anion, followed by cyclization, halogenation, and Suzuki coupling. We found that the ER accommodates 1,3,4-triaryl-pyrazoles of the isomeric series only somewhat less well than the original 1,3,5-triaryl series, and it appears that both series share a common binding mode. This preferred orientation for the 1,3,5-triaryl-4-alkyl-pyrazoles is supported by binding affinity measurements of analogues in which the phenolic hydroxyl groups were systematically removed from each of the three aryl groups, and the orientation is consistent, as well, with molecular modeling studies. These studies provide additional insight into the design of heterocyclic core structures for the development of high affinity ER ligands by combinatorial methods.

Animals↗
PubMed1986

Inhibition of microsomal oxidation of ethanol by pyrazole and 4-methylpyrazole in vitro. Increased effectiveness after induction by pyrazole and 4-methylpyrazole.

Pyrazole and 4-methylpyrazole, which are inhibitors of alcohol dehydrogenase, were also found to be effective inhibitors of the oxidation of ethanol by liver microsomes (microsomal fractions) in vitro. Ethanol oxidation by microsomes from rats previously treated for 2 or 3 days with either pyrazole or 4-methylpyrazole appeared to be especially sensitive to inhibition in vitro by pyrazole or 4-methylpyrazole. The kinetics of inhibition by pyrazole or 4-methylpyrazole in all microsomal preparations were mixed, as the Km for ethanol was elevated while Vmax was lowered. However, Ki values for pyrazole (about 0.35 mM) and especially 4-methylpyrazole (about 0.03-0.10 mM) were much lower than those found with the saline controls (about 0.7-1.1 mM). In contrast, Ki values for dimethyl sulphoxide as an inhibitor of microsomal ethanol oxidation were similar in all microsomal preparations. Pyrazole and 4-methylpyrazole reacted with microsomes to produce type II spectral changes whose magnitude increased after treatment with either pyrazole or 4-methylpyrazole. Thus the increased inhibitory effectiveness of pyrazole and 4-methylpyrazole appears to be associated with increased interactions with the cytochrome P-450 isoenzyme(s) induced by these compounds. These isoenzymes have properties similar to those of the isoenzyme induced by chronic ethanol treatment. Therefore, caution is needed in the use of pyrazole or 4-methylpyrazole to assess pathways of ethanol metabolism, especially after chronic ethanol treatment, since these agents, besides inhibiting alcohol dehydrogenase, are also effective inhibitors of microsomal ethanol oxidation.

Animals↗
PubMed1988

Pyrazole is different from acetone and ethanol as an inducer of the polysubstrate monooxygenase system in mice: evidence that pyrazole-inducible P450Coh is distinct from acetone-inducible P450ac.

The induction of liver microsomal monooxygenase activities elicited by pyrazole, ethanol, and acetone, all shown to be inducers of rat P450j and rabbit P450LM3a, has been compared in inbred strains of DBA/2N, AKR/J, and Balb/c mouse. Pyrazole strongly increases coumarin 7-hydroxylase (COH) activity in DBA/2N but much less in other strains. The effect of pyrazole on aniline p-hydroxylase and ethanol oxidase activities is also strain dependent: an increase was seen only in the DBA/2N strain. Ethanol and acetone were unable to induce COH, whereas aniline p-hydroxylase and ethanol oxidase were elevated about 1.4- to 3.3-fold in all strains. No strain difference could be detected in aniline p-hydroxylase or ethanol oxidase inducibility. There was a strong correlation between aniline p-hydroxylase and ethanol oxidase activities in every strain, whereas no positive correlation could be found between COH and aniline p-hydroxylase activities. Immunoinhibition experiments showed that a polyclonal antibody against purified pyrazole-inducible COH (P450Coh) blocked about 90% of COH activity, but only about 10% of aniline p-hydroxylase or ethanol oxidase in mouse liver microsomes. Monoclonal antibody 1-91-3 (raised against rat acetone-inducible P450ac) did not inhibit COH, whereas aniline p-hydroxylase was blocked 46-76% and ethanol oxidase 25-70%, depending on the source of microsomes. In immunoblots, anti-P450Coh recognized only its own antigen but not the P450ac, whereas monoclonal antibody 1-98-1 against P450ac detected P450ac and a corresponding form in the D2 mouse liver, but not the P450Coh. The purified P450ac and P450Coh had molecular masses of 52 and 50 kDa, respectively, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These antigens were expressed differentially in response to pyrazole, ethanol, and acetone: P450Coh was increased only after pyrazole treatment, but 1-98-1-detectable protein was elevated in D2 mouse liver microsomes by ethanol and acetone, but not by pyrazole. We conclude that mouse P450Coh and rat P450ac are not corresponding forms of the same isozyme, and that a P450ac-like protein, responsible for most of aniline p-hydroxylation and ethanol oxidation, is present in the D2 mouse liver. These two P450 isozymes are also dissimilarly expressed in the mouse liver in response to inducer administration.

Acetone↗
PubMed2006

Unusual reaction between (nitrile)Pt complexes and pyrazoles: substitution proceeds via metal-mediated nitrile-pyrazole coupling followed by elimination of the nitrile.

The reaction of platinum(IV) complex trans-[PtCl4(EtCN)2] with pyrazoles 3,5-RR'pzH (R/R' = H/H, Me/H, Me/Me) leads to the formation of the trans-[PtCl4{NH=C(Et)(3,5-RR'pz)}2] (1-3) species due to the metal-mediated nitrile-pyrazole coupling. Pyrazolylimino complexes 1-3 (i) completely convert to pyrazole complexes cis-[PtCl4(3,5-RR'pzH)2] by elimination of EtCN upon reflux in a CH2Cl2 solution or upon heating in the solid state; (ii) undergo exchange at the imino C atom with another pyrazole different from that contained in the pyrazolylimino ligand. The reaction of trans-[PtIICl2(EtCN)2] and 3,5-RR'pzH, conducted under conditions similar to those for trans-[PtIVCl4(EtCN)2], is much less selective, and the composition of the products strongly depends on the pyrazole employed: (a) with pzH, the reaction gives a mixture of three products, i.e., [PtCl2NH=C(Et)pz-kappa2N,N}] (4), [PtCl(pzH){NH=C(Et)pz-kappa2N,N}]Cl (5), and [Pt(pzH)2{NH=C(Et)pz-kappa2N,N}]Cl2 (6) (complexes 5 and 6 are rather unstable and gradually transform to trans-[PtCl2(pzH2] and [Pt(pzH)(4)]Cl(2) and free EtCN); (b) with 3,5-Me(2)pzH, the reaction leads to the formation of [PtCl2NH=C(Et)(3,5-Me2pz)-kappa2N,N}] (7) and [PtCl(3,5-Me2pzH)3]Cl (8); (c) in the case of asymmetric pyrazole 3(5)-MepzH, which can be added to EtCN and/or bind metal centers by any of the two nonequivalent nitrogen sites, a broad mixture of currently unidentified products is formed. The reduction of 1-3 with Ph3P=CHCO2Me in CHCl3 allows for the formation of corresponding platinum(II) compounds trans-[PtCl2{NH=C(Et)(3,5-RR'pz)}2] (9-11). Ligands NH=C(Et)(3,5-RR'pz) (12-14) were almost quantitatively liberated from 9-11 with 2 equiv of 1,2-bis-(diphenylphosphino)ethane in CDCl3, giving free imines 12-14 in solution and the precipitate of trans-[Pt(dppe)2](Cl)2. Pyrazolylimines 12-14 undergo splitting in CDCl3 solution at 20-25 degrees C for ca. 20 h to furnish the parent propiononitrile and the pyrazole 3,5-RR'pzH, but they can be synthetically utilized immediately after the liberation.

Journal Article↗
PubMed2004

Spontaneous self-assembly of an unsymmetric trinuclear triangular copper(II) pyrazolate complex, [Cu3(micro3-OH)(micro-pz)3(MeCOO)2(Hpz)] (Hpz = pyrazole). synthesis, experimental and theoretical characterization, reactivity, and catalytic activity.

The almost quantitative formation of the triangular trinuclear copper derivative [Cu3(3-OH)(-pz)3(MeCOO)2(Hpz)] (1) (Hpz = pyrazole), has been simply achieved by adding Hpz to an ethanol solution of Cu(MeCOO)2 x H2O. An X-ray molecular structure determination shows that 1 is completely unsymmetric and that trinuclear units result assembled in an extended bidimensional network formed through acetate bridges and hydrogen bonds. EPR and magnetic measurements are consistent with the presence of a single unpaired electron. Theoretical density functional calculations carried out for S = 1/2 provide a thorough description of the electronic structure of 1, allowing a detailed assignment of its UV-vis absorption spectrum. Compound 1 reacts with MeONa, yielding [Cu3(micro3-OH)(micro-pz)3(MeCOO)(MeO)(Hpz)] (2) and [Cu3(micro3-OH)(micro-pz)3(MeO)2(Hpz)] (3) through the substitution of one and two acetate ions, respectively, with MeO- ion(s). The spontaneous self-assembly of the triangular trinuclear Cu3 moiety seems to occur only with pyrazole as can be inferred by the results obtained in the reactions of copper(II) acetate with some substituted pyrazoles leading to the formation of mononuclear [Cu(MeCOO)2(L)2] (4-8) and dinuclear [Cu(MeCOO)2(L)]2 (9-11) (L = substituted pyrazole) compounds. Also the presence of acetate ions seems to play a leading role in determining the formation of the trinuclear triangular arrangement, as indicated by the formation of a mononuclear derivative, [Cu(CF3COO)2(Hpz)]2 (compound 12), in the reaction of copper(II) trifluoroacetate with pyrazole. Compounds 1-3, as well as some other mono- and dinuclear copper(II)-substituted pyrazole complexes, have been tested as catalyst precursors in cyclopropanation reaction, observing the formation of products in a syn:anti ratio opposite that normally reported.

Journal Article↗
PubMed2000

Inverse agonist properties of N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide HCl (SR141716A) and 1-(2-chlorophenyl)-4-cyano-5-(4-methoxyphenyl)-1H-pyrazole-3-carboxyl ic acid phenylamide (CP-272871) for the CB(1) cannabinoid receptor.

Two subtypes of cannabinoid receptors are currently recognized, CB(1), found in brain and neuronal cells, and CB(2), found in spleen and immune cells. We have characterized 1-(2-chlorophenyl)-4-cyano-5-(4-methoxyphenyl)-1H-pyrazole-3-carboxyl ic acid phenylamide (CP-272871) as a novel aryl pyrazole antagonist for the CB(1) receptor. CP-272871 competed for binding of the cannabinoid agonist (3)H-labeled (-)-3-[2-hydroxy-4-(1, 1-dimethylheptyl)-phenyl]-4-[3-hydroxypropyl]cyclohexan-1-ol ([(3)H]CP-55940) at the CB(1) receptor in rat brain membranes with a K(d) value 20-fold greater than that of N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide HCl (SR141716A). CP-272871 also competed for binding with the aminoalkylindole agonist (3)H-labeled (R)-(+)-[2, 3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]1, 4-benzoxazin-6-yl](1-naphthyl)methanone ([(3)H]WIN-55212-2), as well as the aryl pyrazole antagonist [(3)H]SR141716A. Inverse agonist as well as antagonist properties were observed for both SR141716A and CP-272871 in signal transduction assays in biological preparations in which the CB(1) receptor is endogenously expressed. SR141716A augmented secretin-stimulated cyclic AMP (cAMP) accumulation in intact N18TG2 neuroblastoma cells, and this response was reversed by the agonist desacetyllevonantradol. CP-272871 antagonized desacetyllevonantradol-mediated inhibition of adenylyl cyclase in N18TG2 membranes, and increased adenylyl cyclase activity in the absence of agonist. SR141716A and CP-272871 antagonized desacetyllevonantradol-stimulated (35)S-labeled guanosine-5'-O-(gamma-thio)-triphosphate ([(35)S]GTPgammaS) binding to brain membrane G-proteins, and decreased basal [(35)S]GTPgammaS binding to G-proteins. K(+) enhanced CP-272871 and SR141716A inverse agonist activity compared with Na(+) or NMDG(+) in the assay. These results demonstrated that the aryl pyrazoles SR141716A and CP-272871 behave as antagonists and as inverse agonists in G-protein-mediated signal transduction in preparations of endogenously expressed CB(1) receptors.

Animals↗
PubMed1988

Induction of rat hepatic microsomal drug metabolizing enzymes by pyrazole and 4-substituted pyrazoles.

Pyrazole and 4-methylpyrazole are potent inhibitors of liver alcohol dehydrogenase and as such have been proposed as potential antidotes to alcohol poisoning. These drugs are also inducers of hepatic cytochrome P-450. We tested pyrazole and four 4-substituted pyrazoles for their potential as inducers of cytochrome P-450 and drug metabolism in mature male rats. Total cytochrome P-450 was significantly increased (p less than 0.05) 1.3 fold by treatment with 4-methylpyrazole. P-nitrophenol hydroxylase (PNPH) activity (nmol/min/mg protein) was increased 1.9 fold following treatment with pyrazole and with 4-methylpyrazole. Treatment with 4-methylpyrazole also resulted in a 2.9 fold increase in ethoxyresorufin demethylase (EROD) activity. In addition, pyrazole treatment led to a significant decrease in the activity of benzphetamine demethylase. 4-Iodopyrazole increased the turnover (nmol/min/nmol P-450) of EROD and PNPH by 1.5 fold each. 4-Nitropyrazole had no significant effect on any of the activities or turnover rates tested. In contrast to results with cultured chick hepatocytes, where induction was directly related to the hydrophobicity of the 4-substituent, the present data indicate that the process of induction of in vivo is more complex.

Animals↗
PubMed1986

Mutagenicity study on pyrazole, seven pyrazole derivatives, and two nitroimidazoles with the L-arabinose resistance test of Salmonella typhimurium.

The mutagenicity of pyrazole and seven pyrazole derivatives (4-nitropyrazole, 4-bromopyrazole, 1-methyl-4-nitropyrazole, 3,5-dimethyl-4-nitropyrazole, 1-methyl-4-bromopyrazole, 4,4'-dinitro-1, 1'-methylene-dipyrazole and 4,4'-dibromo-1,1'-methylene-dipyrazole) has been investigated with the L-arabinose forward mutation assay of Salmonella typhimurium. Two nitroimidazoles (1-methyl-5-nitroimidazole and metronidazole) were included as reference drugs. The mutagenicity of each chemical was determined by both preincubation and liquid tests, in the presence or absence of S9 microsomal fraction. The mutagenic response was expressed as the absolute number of L-arabinose resistant mutants growing in selective plates, supplemented with traces of D-glucose. Strain BA13 with a wildtype lipopolysaccharide barrier was used as a comparison to the deep rough derivative BA9. No mutagenic effect was detected with pyrazole and two of its derivatives, 1-methyl-4-bromopyrazole and 4,4'-dibromo-1,1'-methylene-dipyrazole. The other five pyrazole derivatives were mutagenic to different degrees, although their mutagenic potencies were always considerably lower than those of the two nitroimidazoles. The results suggest that 4-nitropyrazoles, as well as 4,4'-dinitro-1, 1'-methylene-dipyrazoles, should be investigated further as alternatives to, or even substitutes for, the currently used nitroimidazoles.

Antitrichomonal Agents↗
PubMed1992

Pyrazole-related nucleosides. Synthesis and antiviral/antitumor activity of some substituted pyrazole and pyrazolo[4,3-d]-1,2,3-triazin-4-one nucleosides.

Several pyrazole and pyrazolo[4,3-d]-1,2,3-triazin-4-one ribonucleosides were prepared and tested for antiviral/antitumor activities. Appropriate heterocyclic bases were prepared by standard methodologies. Glycosylation of pyrazoles 6a-e,g,i and of pyrazolo[4,3-d]-1,2,3-triazin-4-ones 12f-1 mediated by silylation with hexamethyldisilazane, with 1-beta-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose, gave in good yields the corresponding glycosides 7a-e,g, 8g,i, 13f,h,k, and 14f, but could not be applied to compounds 12g,i,j,l. To overcome this occurrence, a different strategy involving the preparation, diazotization, and in situ cyclization of opportune pyrazole glycosides 9 and 10 was required. Moreover derivatives having the general formula 5 were considered not only as synthetic intermediates in the synthesis of 3 but also as carbon bioisosteres of ribavirin 4. All compounds were evaluated in vitro for cytostatic and antiviral activity. The pyrazolo[4,3-d]-1,2,3-triazin-4-one nucleosides that resulted were substantially devoid of any activity; only 15h,k showed a moderate cytostatic activity against T-cells. However, pyrazole nucleosides 9b,c,e were potent and selective cytotoxic agents against T-lymphocytes, whereas 9e showed a selective, although not very potent, activity against coxsackie B1.

Animals↗
PubMed1992

3,5-Diphenyl-1H-pyrazole derivatives. X. N-substituted 1-(2-aminopropyl)- and 1-(3-amino-2-hydroxypropyl)-3,5-diphenyl-1H-pyrazoles with antiinflammatory and other activities.

The syntheses of 1-(2-hydroxypropyl)-3,5-diphenyl-1H-pyrazole 1 by reaction of 1-hydrazino-2-propanol with dibenzoylmethane and of N-substituted 1-(2-aminopropyl)-3,5-diphenyl-1H-pyrazoles 3 by reaction of primary and secondary amines with the tosylate of 1, as well as of N-substituted 1-(3-amino-2-hydroxypropyl)-3,5-diphenyl-1H-pyrazoles 6 starting from 3,5-diphenyl-1H-pyrazole, are described. Some compounds 3 and 6 showed remarkable antiinflammatory activity in rats, as well as weak analgesic, antipyretic, antiarrhythmic, hypotensive activities in mice and rats and moderate platelet antiaggregating effects in vitro.

Animals↗
PubMed2006

1-Acetyl-3-ferrocenyl-5-methyl-1H-pyrazole and 1-acetyl-5-ferrocenyl-3-(2-pyridyl)-1H-pyrazole.

Molecules of 1-acetyl-3-ferrocenyl-5-methyl-1H-pyrazole, [Fe(C5H5)(C11H11N2O)], form a centrosymmetric dimer generated by a combination of one C-H...pi(pyrazole) and one C-H...pi(cyclopentadienyl) interaction. The dimers are linked by C-H...pi interactions, involving the pyrazole rings as acceptors, into layers parallel to (10-1). Molecules of 1-acetyl-5-ferrocenyl-3-(2-pyridyl)-1H-pyrazole, [Fe(C5H5)(C15H12N3O)], are linked by C-H...O interactions into a chain running in the [010] direction. Two chains of this type passing through each unit cell are connected by O...pi(pyridyl) interactions into an [010] double chain.

Journal Article↗