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Showing papers on "Pyrazole published in 2005"


Journal ArticleDOI
TL;DR: Coupling reaction of electron-deficient aryl bromides with imidazole or pyrazole occurs at 60-90 degrees C to provide the corresponding N-aryl products in good to excellent yields and the possible action of amino acids in these coupling reactions is discussed.
Abstract: CuI-catalyzed coupling reaction of electron-deficient aryl iodides with aliphatic primary amines occurs at 40 degrees C under the promotion of N-methylglycine. Using L-proline as the promoter, coupling reaction of aryl iodides or aryl bromides with aliphatic primary amines, aliphatic cyclic secondary amines, or electron-rich primary arylamines proceeds at 60-90 degrees C; an intramolecular coupling reaction between aryl chloride and primary amine moieties gives indoline at 70 degrees C; coupling reaction of aryl iodides with indole, pyrrole, carbazole, imidazole, or pyrazole can be carried out at 75-90 degrees C; and coupling reaction of electron-deficient aryl bromides with imidazole or pyrazole occurs at 60-90 degrees C to provide the corresponding N-aryl products in good to excellent yields. In addition, N,N-dimethylglycine promotes the coupling reaction of electron-rich aryl bromides with imidazole or pyrazole to afford the corresponding N-aryl imidazoles or pyrazoles at 110 degrees C. The possible action of amino acids in these coupling reactions is discussed.

599 citations


Journal ArticleDOI
TL;DR: 5-phenoxypyrazole was comparable to doxorubicin, while exhibiting very potent cytotoxicity against XF 498 and HCT15, and pyrazole oxime ether derivatives prepared and examined as cytotoxic agents.

286 citations


Journal ArticleDOI
TL;DR: Molecular docking study revealed the binding orientations of curcumin analogues in the active sites of COX and thereby helps to design novel potent inhibitors.

278 citations


Journal ArticleDOI
TL;DR: Mixed (difluoro)phenylpyridine/pyrazole tris-cyclometalated iridium complexes were prepared in order to study the effect of fluorination and the pyridine / pyrazole ratio on the emission and electrochemical properties.
Abstract: Mixed (difluoro)phenylpyridine/(difluoro)phenylpyrazole tris-cyclometalated iridium complexes were prepared in order to study the effect of fluorination and the pyridine/pyrazole ratio on the emission and electrochemical properties. Increasing fluorination and replacement of pyridine by pyrazole both leads to a widening of the HOMO-LUMO gap and generally leads to a blue shift in emission.

238 citations


Journal ArticleDOI
TL;DR: It is concluded that, for complexes 1-3, the weakening of iridium metal-ligand bonding strength in the T(1) state plays a crucial role for the fast radiationless deactivation of Ir(III) metal complexes.
Abstract: A series of heteroleptic Ir(III) metal complexes 1−3 bearing two N-phenyl-substituted pyrazoles and one 2-pyridyl pyrazole (or triazole) ligands were synthesized and characterized to attain highly efficient, room-temperature blue phosphorescence. The N-phenylpyrazole ligands, dfpzH = 1-(2,4-difluorophenyl)pyrazole, fpzH = 1-(4-fluorophenyl)pyrazole, dfmpzH = 1-(2,4-difluorophenyl)-3,5-dimethylpyrazole, and fmpzH = 1-(4-fluorophenyl)-3,5-dimethylpyrazole, show a similar reaction pattern with respect to the typical cyclometalated (C∧N) chelate, which utilizes its ortho-substituted phenyl segment to link with the central Ir(III) atom, while the second 2-pyridylpyrazole (or triazole) ligand, namely, fppzH = 3-(trifluoromethyl)-5-(2-pyridyl)pyrazole, fptzH = 3-(trifluoromethyl)-5-(2-pyridyl)triazole, and hptzH = 3-(heptafluoropropyl)-5-(2-pyridyl)triazole, undergoes typical anionic (N∧N) chelation to complete the octahedral framework. X-ray structural analyses on complexes [(dfpz)2Ir(fppz)] (1a) and [(fmpz)2Ir...

203 citations


Patent
11 Jun 2005
TL;DR: In this paper, the substituents of 1-methyl-3-trifluoromethyl-pyrazole-4-carboxylic acid-(ortho-phenyl)-anilides of formula I were defined.
Abstract: The invention relates to 1-methyl-3-trifluoromethyl-pyrazole-4-carboxylic acid-(ortho-phenyl)-anilides of formula I, wherein the substituents have the following meaning: R1 and R 2 independently represent halogen, C1-C6-alkyl, C1-C6 halogen-alkyl, cyano, nitro, methoxy, trifluoromethoxy or difluoromethoxy; under the proviso that if R2 represents chlorine in the 4-position, R1 does not represent trifluoromethyl in the 3 position.

200 citations


Journal ArticleDOI
TL;DR: Modification of a series of pyrazole factor Xa inhibitors to incorporate an aminobenzisoxazole as the P(1) ligand resulted in compounds with improved selectivity forfactor Xa relative to trypsin and plasma kallikrein and was selected for clinical development as razaxaban.
Abstract: Modification of a series of pyrazole factor Xa inhibitors to incorporate an aminobenzisoxazole as the P1 ligand resulted in compounds with improved selectivity for factor Xa relative to trypsin and plasma kallikrein. Further optimization of the P4 moiety led to compounds with enhanced permeability and reduced protein binding. The SAR and pharmacokinetic profile of this series of compounds is described herein. These efforts culminated in 1-(3‘-aminobenzisoxazol-5‘-yl)-3-trifluoromethyl-N-[2-fluoro-4-[(2‘-dimethylaminomethyl)imidazol-1-yl]phenyl]-1H-pyrazole-5-carboxyamide (11d), a potent, selective, and orally bioavailable inhibitor of factor Xa. On the basis of its excellent in vitro potency and selectivity profile, high free fraction in human plasma, good oral bioavailability, and in vivo efficacy in antithrombotic models, the HCl salt of this compound was selected for clinical development as razaxaban (DPC 906, BMS-561389).

193 citations


Journal ArticleDOI
TL;DR: Four-component coupling of a terminal alkyne, hydrazine (hydroxylamine), carbon monoxide, and an aryl iodide furnishes pyrazole or isoxazole derivatives in the presence of a palladium catalyst.

193 citations


Journal ArticleDOI
TL;DR: In this article, a facile synthesis of 4-pyrazolyl 1,4-dihydropyridines at room temperature by cyclocondensation of ethyl 3-aminocrotonate, pyrazole aldehyde and a β-keto ester is reported.

164 citations


Journal ArticleDOI
TL;DR: In this article, the RuII(bipy)(terpy)L](PF6)2 with bipy = 2.2′-bipyridine, terpy = 2,2′:6′,2″-terpyridine and L = H2O, imidazole, 4,5-diphenylimidazoles and indazole have been synthesized and characterized by 1H NMR, ESI-MS and UV/Vis.
Abstract: Compounds [RuII(bipy)(terpy)L](PF6)2 with bipy = 2,2′-bipyridine, terpy = 2,2′:6′,2″-terpyridine, L = H2O, imidazole (imi), 4-methylimidazole, 2-methylimidazole, benzimidazole, 4,5-diphenylimidazole, indazole, pyrazole, 3-methylpyrazole have been synthesized and characterized by 1H NMR, ESI-MS and UV/Vis (in CH3CN and H2O). For L = H2O, imidazole, 4,5-diphenylimidazole and indazole the X-ray structures of the complexes have been determined with the crystal packing featuring only few intermolecular C–H⋯π or π–π interactions due to the separating action of the PF6-anions. Complexes with L = imidazole and 4-methylimidazole exhibit a fluorescence emission with a maximum at 662 and 667 nm, respectively (λexc = 475 nm, solvent CH3CN or H2O). The substitution of the aqua ligand in [Ru(bipy)(terpy)(H2O)]2+ in aqueous solution by imidazole to give [Ru(bipy)(terpy)(imi)]2+ is fastest at a pH of 8.5 (as followed by the increase in emission intensity). Coupling of the [Ru(bipy)(terpy)]2+ fragment to cytochrome c (Yeast iso-1) starting from the Ru-aqua complex was successful at 35 °C and pH 7.0 after 5 d under argon in the dark. The [Ru(bipy)(terpy)(cyt c)]-product was characterized by UV/Vis, emission and mass spectrometry. The location where the [Ru(bipy)(terpy)] complex was coupled to the protein was identified as His44 (corresponding to His39 in other numbering schemes) using digestion of the Ru-coupled protein by trypsin and analysis of the tryptic peptides by HPLC-high resolution MS.

147 citations


Journal ArticleDOI
TL;DR: A series of substituted pyrazolines were synthesized and evaluated for their anticancer activity and for their ability to inhibit P-glycoprotein-mediated multidrug resistance by direct binding to a purified protein domain containing an ATP-binding site and a modulator interacting region.

Journal ArticleDOI
TL;DR: Compound 6c, proved to be the most active anti‐inflammatory‐antimicrobial agent in the present study with a good safety margin and no ulcerogenic effect.
Abstract: Four series of 7//-pyrazole derivatives have been synthesized. The first series was synthesized starting by condensing the hydrazine derivatives la-d with 4-(l-ethoxycarbonyl-2-oxopropyl)azobenzoic acid 2a in ethanol or glacial acetic acid to generate the corresponding pyrazoline derivatives 3a-d. Likewise, heating la-d with 4-(l-acetyl-2-oxopropyl)azobenzoic acid 2b gave rise to the pyrazole derivatives 4a-d. Similarly, reaction of la-d with ethyl 2-(l,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-ylazo)-3-oxobutanoate 2c or 3-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-lH-pyrazol-4-yl-azo)pentane-2,4-dione 2d in ethanol or glacial acetic acid led to the corresponding pyrazoline derivatives 5a-d or pyrazole derivatives 6a-d. The newly synthesized compounds were evaluated for their anti-inflammatory-antimicrobial activities. In addition, the ulcerogenic and acute toxicity profiles were determined. Compound 6c, proved to be the most active anti-inflammatory-antimicrobial agent in the present study with a good safety margin and no ulcerogenic effect.

Journal ArticleDOI
TL;DR: The docking study was carried out using several computational approaches with the aim of proposing possible binding modes of the MAO enantioselective compounds 1 and 4, and found the selectivity of the (-)-(S)-1 enantiomer against MAO-B increases twice and a half, while the selectability of the (+)- (S)-4 enantiomers againstMAO-A triples increases three times.
Abstract: A novel series of 1-thiocarbamoyl-3,5-diaryl-4,5-dihydro-(1H)-pyrazole derivatives have been synthesized and investigated for the ability to inhibit selectively the activity of the A and B isoforms of monoamine oxidase (MAO). All the synthesized compounds show high activity against both the MAO-A and the MAO-B isoforms with Ki values between 27 and 4 nM and between 50 and 1.5 nM, respectively, except for a few derivatives whose inhibitory activity against MAO-B was in the micromolar range. Knowing that stereochemistry may be an important modulator of biological activity, we performed the semipreparative chromatographic enantioseparation of the most potent, selective, and chiral compounds. The separated enantiomers were then submitted to in vitro biological evaluation. The selectivity of the (−)-(S)-1 enantiomer against MAO-B increases twice and a half, while the selectivity of the (−)-(S)-4 enantiomer against MAO-A triples. Both the MAO-A and MAO-B isoforms respectively of the 1O5W and 1GOS models deposit...

Journal ArticleDOI
TL;DR: Many of the 5-[(E)-2-arylvinyl]pyrazoles synthesized in this study exhibited potent antibacterial activity against quinolone-resistant clinical isolates of gram-positive bacteria with minimal inhibitory concentration values equivalent to those against susceptible strains.

Patent
15 Aug 2005
TL;DR: In this paper, the c-Met protein kinase inhibitors are used in the treatment of abnormal cell growth disorders, such as cancers, and methods for their synthesis and use are described.
Abstract: Compounds of formula (1) are provided, as well as methods for their synthesis and use Preferred compounds are potent inhibitors of the c-Met protein kinase, and are useful in the treatment of abnormal cell growth disorders, such as cancers

Journal ArticleDOI
TL;DR: Accessing an extra interaction with the protein via Phe138 gave a significant increase in binding potency compared to similar analogues that do not make this interaction.

Journal ArticleDOI
TL;DR: Twenty-six epoxide and corresponding pyrazole derivatives, of the structurally related chalcones and combretastatin A-4 (CA-4), were synthesized and tested for in vitro cytotoxicity, with the most active pyrazoles generally more active than the epoxides.

Journal ArticleDOI
TL;DR: In this article, a series of imidzoalium salt compounds for the potentially bidentate pyrazole/N-heterocyclic carbene was synthesized.

Journal ArticleDOI
TL;DR: Based on investigations and those of others, E-ring modified steroids were identified as a useful template for the design of inhibitors of 17beta-HSD type 1, an enzyme involved in the conversion of estrone into estradiol.
Abstract: 17beta-Hydroxysteroid dehydrogenases (17beta-HSDs) are an important class of steroidogenic enzymes that regulate the bioavailability of active estrogens and androgens and are as yet a relatively unexploited therapeutic target. Based on our investigations and those of others, E-ring modified steroids were identified as a useful template for the design of inhibitors of 17beta-HSD type 1, an enzyme involved in the conversion of estrone into estradiol. The synthesis and biological evaluation of a new series of N- and C-substituted 1,3,5(10)-estratrien-[17,16-c]-pyrazoles and the corresponding SAR are discussed. Among the N-alkylated analogues, the most potent inhibitor was the 1'-methoxyethyl derivative, 41, with an IC(50) of 530 nM in T47-D human breast cancer cells. The X-ray crystal structure of the 1'-isobutyl derivative, was determined. Further optimization of the template using parallel synthesis resulted in a library of C5'-linked amides from which 73 emerged. This pyridylethyl amide had an IC(50) of 300 nM and its activity, with that of 41, suggests the importance of hydrogen bond acceptor groups in the pyrazole side chain. Both 41 and 73 displayed selectivity over 17beta-HSD type 2, and preliminary investigations showed 41 to be nonestrogenic in vitro in a luciferase reporter gene assay in contrast to the parent pyrazole 25. Molecular modeling studies, which support these findings, and a QSAR, the predictive power of which was demonstrated, are also presented.

Journal ArticleDOI
TL;DR: Electrophilic amination of primary aliphatic and aromatic amines is reported using a diethylketomalonate-derived oxaziridine to afford the corresponding N-Boc hydrazines in good to excellent yields.

Journal ArticleDOI
TL;DR: Differences in properties between kinetic behavior and regio-isomerism depending on the degree of electron-withdrawing capability of the R and Ar substituents are observed.
Abstract: Arylhydrazines 4 and 1,3-dicarbonyl compounds 5 react to form pyrazoles by loss of water via hydrazone isomer pairs 6 and 7 which give rise to two possible regio-isomers Occasionally, 3-hydroxy-3,4-dihydropyrazoles or hydroxy-pyrazolines 8 and 9 are observed as stable isolatable intermediates that can be fully characterized prior to loss of the second molecule of water that gives rise to pyrazoles 10 and 11 Fully characterized examples of intermediates of type 8 and 9 are relatively rare We studied the reaction series where R = CH3, CHF2 and CF3 and Ar = Ph and 5-methanesulfonylpyridin-2-yl, (Scheme 2), and observed differences in properties between kinetic behavior and regio-isomerism depending on the degree of electron-withdrawing capability of the R and Ar substituents The reaction conditions that caused cyclization to pyrazoles varied from direct condensation of the hydrazine and 1,3-dicarbonyl compounds, to reactions requiring catalytic quantities of sulfuric acid to sulfuric acid in excess Unexpected regio-selectivity was observed in the case of R = CF3 that depended upon the reaction conditions

Journal ArticleDOI
01 Jan 2005-Farmaco
TL;DR: The results of this research showed that the compound named as 5c was the best compound in the series, exhibiting antibacterial activity against both Gram-positive and Gram-negative bacteria.
Abstract: Some new 1H-pyrazole-3-carboxylic acid and pyridazinone derivatives were synthesized and evaluated for their antibacterial activities against Bacillus cereus ATCC 7064, Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 4230 and Pseudomonas putida using tube dilution method. The minimal inhibitory concentrations (MICs) experiments revealed that all chemical compounds showed inhibitor effects on the growth of the test microorganisms. Moreover, the results of this research showed that the compound named as 5c was the best compound in the series, exhibiting antibacterial activity against both Gram-positive and Gram-negative bacteria.

Journal ArticleDOI
TL;DR: A series of dihydroxyphenylpyrazole compounds were identified as a unique class of reversible Hsp90 inhibitors as mentioned in this paper, which fit deeply into the adenine binding pocket with the C2 hydroxyl group forming a direct hydrogen bond with the side chain of Asp93.

Journal ArticleDOI
TL;DR: In this article, a single-step synthesis of 4,5-dihydro-pyrazole, pyrazolidine, and 1,2-dhydrophthalazine derivatives via double-alkylation of hydrazines by alkyl dihalides or ditosylates was performed in aqueous media under microwave irradiation conditions.

Patent
30 Dec 2005
TL;DR: In this article, a compound of the formula (I): for use in medicine: or salts or tautomers or N-oxides or solvates thereof; wherein R1 is an optionally substituted heterocyclic group having from 3 to 12 ring members provided that the cyclic group joined to the pyrazole contains at least one heteroatom selected from N, O or S.
Abstract: The invention provides a compound of the formula (I): for use in medicine: or salts or tautomers or N-oxides or solvates thereof; wherein R1 is an optionally substituted heterocyclic group having from 3 to 12 ring members provided that the cyclic group joined to the pyrazole contains at least one heteroatom selected from N, O or S; A is a bond or -Y-(B)n-; B is C=O, NRg(C=O) or O(C=O) wherein Rg is hydrogen or C1-4 hydrocarbyl optionally substituted by hydroxy or C1-4 alkoxy; n is 0 or 1; Y is a bond or an alkylene chain of 1,2 or 3 carbon atoms in length; R2 is hydrogen; halogen; C1-4 alkoxy (e.g. methoxy); or a C1-4 hydrocarbyl group optionally substituted by halogen (e.g. fluorine), hydroxyl or C1-4 alkoxy (e.g. methoxy); R3 is selected from optionally substituted carbocyclic and heterocyclic groups having from 3 to 12 ring members or an optionally substituted C1-8 hydrocarbyl group; with the proviso that R1 is not formula (II): where X, R3’ and R4’ are defined in the claims.

Journal ArticleDOI
TL;DR: In this paper, the steric and electronic effects of the ligands were studied over the catalytic activity toward polyethylene polymerization, and it was shown that the presence of methyl groups (R = CH 3 ) in iron and cobalt complexes allowed to obtain polyethylenes with molecular weights higher than the one obtained with complexes without these methyl groups.
Abstract: The complexes Py(PzR 3 ) 2 MCl 2 (R = H, Me; M = Fe, Co) and Py(CH 2 PzR 3 ) 2 MCl 2 (R = H, Me; M = Fe, Co) have been synthesized, characterized and used in the ethylene polymerization. Treatment of these iron and cobalt complexes with methylaluminoxane (MAO) as cocatalyst leads to active ethylene polymerization catalysts that produced linear polyethylene. In general, iron catalysts were more active than cobalt analogs. The steric and electronic effects of the ligands were study over the catalytic activity toward ethylene polymerization. Complexes with small substituents groups (R = H) on the pyrazolyl ring, increase the catalytic activity in comparison to complexes with bigger substituents groups (R = CH 3 ). Additionally, complexes with methylene groups placed between pyridine and pyrazole rings of ligands have less catalytic activity than complexes without the methylene group ( CH 2 ). The presence of methyl groups (R = CH 3 ) in iron and cobalt complexes allow to obtain polyethylene with molecular weights higher than the one obtained with complexes without these methyl groups. Additionally, complexes with methylene groups present between pyridine and pyrazole rings generate polyethylenes with molecular weight higher than the ones produced with complexes without these methylene groups.

Journal ArticleDOI
TL;DR: A β-enaminonitrile of 1-(6p-tolyl-pyridazin-3-yl)-pyrazole derivative 2 was formed using (6p tolyl, pyridine-hydrazine) and 2-ethoxymethylenemalononitriles.
Abstract: A novel β -enaminonitrile of 1-(6-p-tolyl-pyridazin-3-yl)-pyrazole derivative 2 was formed using (6-p-tolyl-pyridazin-3-yl)-hydrazine ( 1 ) and 2-ethoxymethylenemalononitrile. The β-enaminonitrile derivative 2 was in turn used as a precursor for the preparation of pyrazoles ( 4 , 6 ), pyrazolo[3, 4-d]-pyrimidines ( 3 , 7–12 ) and pyrazolo[4, 3-e][1,2,4]triazolo[4,3-c]pyrimidine ( 13 ). Also, N- and S-acyclic nucleosides 14 and 15 were prepared. Some of the prepared products showed potent antimicrobial activity.

Journal ArticleDOI
TL;DR: A tetranuclear mixed ligand copper(II) complex of a pyrazole containing Schiff base and a hydroxyhexahydropyrimidylpyrazole and copper-II and nickel-II complexes of the Schiff base having N-donor atoms have been investigated.
Abstract: A tetranuclear mixed ligand copper(II) complex of a pyrazole containing Schiff base and a hydroxyhexahydropyrimidylpyrazole and copper(II) and nickel(II) complexes of the Schiff base having N-donor atoms have been investigated. A 2 equiv amount of 5-methyl-3-formylpyrazole (MPA) and 2 equiv of 1,3-diamino-2-propanol (1,3-DAP) on reaction with 1 equiv of copper(II) nitrate produce an unusual tetranuclear mixed ligand complex [Cu4(L1)2(L2)2(NO3)2] (1), where H2L1 = 1,3-bis(5-methyl-3-formylpyrazolylmethinimino)propane-2-ol and HL2 = 5-methyl-3-(5-hydroxyhexahydro-2-pyrimidyl)pyrazole. In contrast, a similar reaction with nickel(II) nitrate leads to the formation of a hygroscopic intractable material. On the other hand, the reaction involving 2 equiv of MPA and 1 equiv each of 1,3-DAP and various copper(II) salts gives rise to two types of products, viz. [Cu(T3-porphyrinogen)(H2O)]X2 (X = ClO4, NO3, BF4 (2)) (T3-porphyrinogen = 1,6,11,16- tetraza-5,10,15,20- tetrahydroxy-2,7,12,17-tetramethylporphyrinogen) a...

ComponentDOI
TL;DR: One of the identified compounds (G3130) demonstrated cellular activities (in Her-2 degradation and activation of Hsp70 promoter) consistent with the inhibition of cellular Hsp90 functions.

Patent
04 Oct 2005
TL;DR: In this paper, a compound of formula (I) or a pharmaceutically acceptable salt, solvate or N-oxide thereof is defined, wherein A represents a pyrrole, pyrazole, imidazole or triazole ring; B represents a benzene, pyridine or pyrimidine ring; E represents a covalent bond or an optionally substituted straight or branched alkylene chain containing from 1 to 4 carbon atoms.
Abstract: A compound of formula (I) or a pharmaceutically acceptable salt, solvate or N-­oxide thereof: wherein A represents a pyrrole, pyrazole, imidazole or triazole ring; B represents a benzene, pyridine or pyrimidine ring; M represents the residue of an azetidine, pyrrolidine or piperidine ring; E represents a covalent bond or an optionally substituted straight or branched alkylene chain containing from 1 to 4 carbon atoms; Z represents hydrogen, -CORa, -C02Rb, -CONKc Rd, -CONRcORb, -COCO2Rb, - COCONRcRd, -COCH2NRcRd, -COCH2NRcCONKcRd, COCH2NRcCO2Rb, -NRcCORa, - NRcCO2Rb, -NRcCONRcRd, -S02Re, -SO2NRcRd or -SO2NRcC02Rb; or Z represents an optionally substituted phenyl, heteroaryl or C3-7 heterocycloalkyl group; R1 and R2 independently represent hydrogen, halogen, cyano, nitro, C1-6 alkyl, trifluoromethyl, hydroxy, C1-6 alkoxy, difluoromethoxy, trifluoromethoxy, C1-6 alkylsulphonyl, amino, C1-6 alkylamino, di(C1-6)alkylamino, aminocarbonyl or C2-6 alkoxycarbonyl; R3 represents hydrogen, C1-6 alkyl, -CH2CONRcRd or -SO2Re; R4 represents hydrogen, C1-6 alkoxy, oxo, -CO2Rb or -CONKcRd. The compounds of the present invention are potent inhibitors of JNK.