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Showing papers on "Pyrazole published in 1998"


Journal ArticleDOI
Klaus-Dieter Kreuer1, Annette Fuchs1, M. Ise1, M. Spaeth1, Joachim Maier1 
TL;DR: The properties of imidazole (pyrazole) as a solvent for acidic protons in polymers and liquids are reported in this article, where the creation of protonic defects and the mobility of protons are found to be similar to the situation in corresponding water containing systems.

557 citations


Journal ArticleDOI
TL;DR: A biphasic system consisting of 35% H 2 O 2 and methyltrioxorhenium(VII)/pyrazole in CH 2 Cl 2 catalyzes the epoxidation of a wide range of olefins in excellent yields.

137 citations


Journal ArticleDOI
Gamal K. Gomma1
TL;DR: In this paper, the corrosion behavior of steel (0.05% C) in 0.5 M sulphuric acid solution in the presence of pyrazole-halide mixtures was studied.

119 citations


Journal ArticleDOI
TL;DR: In this paper, trialkyl and (triarylphosphine)silver derivatives containing anionic tris(1H-pyrazol-1-yl)borates were prepared from AgX (X = CF3SO3 or NO3), PR3 (R = phenyl, benzyl, cyclohexyl, 2,4,6-trimethylphenyl, or o-, m-, and p-tolyl) or PMePh2, and M[HB(pz)3] [M = K or Na; pz
Abstract: (Trialkyl- and (triarylphosphine)silver(I) derivatives containing anionic tris(1H-pyrazol-1-yl)borates were prepared from AgX (X = CF3SO3 or NO3), PR3 (R = phenyl, benzyl, cyclohexyl, 2,4,6-trimethylphenyl, or o-, m-, and p-tolyl) or PMePh2, and M[HB(pz)3] [M = K or Na; pzH = pyrazole in general; in detail, pyrazole (PzH), 3,5-dimethylpyrazole (3,5-Me2PzH), or 4-bromopyrazole (4-BrPzH)] and characterized through analytical and spectral (IR; 1H, 13C, and 31P NMR) measurements. These air stable, light-sensitive complexes are not electrolytes in CH2Cl2 and acetone. In these solvents they decompose even with strict exclusion of oxygen and light. The solid-state structures show that the silver atom adopts a distorted tetrahedral geometry. Crystal data with Mo Kα (λ = 0.710 70 A) at 293 K: [HB(Pz)3]Ag(PPh3), C54H50Ag2B2N12P2, a = 15.082(2) A, b = 19.728(2) A, c = 9.432(1) A, α = 94.8(1)°, β = 107.4(1)°, γ = 87.8(1)°, triclinic, P1, Z = 2; [HB(Pz)3]Ag[P(o-tolyl)3], C30H31AgBN6P, a = 14.461(2) A, b = 14.461(2) ...

101 citations


Journal ArticleDOI
TL;DR: In this paper, a novel cationic η3-allylpalladium−pyridinyl pyrazole complexes were synthesized from 3-alkyl-5-(2-pyridine)pyrazole and η 3-ally-lpalla chloride dimer in the presence of AgBF4.
Abstract: Novel cationic η3-allylpalladium−pyridinylpyrazole complexes 1a and 1b were synthesized from 3-alkyl-5-(2-pyridinyl)pyrazole and η3-allylpalladium chloride dimer in the presence of AgBF4. Cationic ...

98 citations


Patent
22 May 1998
TL;DR: A class of pyrazole derivatives is described for use in treating p38 kinase mediated disorders in this paper, where compounds of particular interest are defined by Formula (I) wherein Q, R1, R2, R3 and R4 are as described in the specification.
Abstract: not available for EP1019394Abstract of corresponding document: WO9852941A class of pyrazole derivatives is described for use in treating p38 kinase mediated disorders. Compounds of particular interest are defined by Formula (I) wherein Q, R1, R2, R3 and R4 are as described in the specification.

86 citations


Journal ArticleDOI
TL;DR: QSAR studies showed a good correlation of MDR-modulating activity with lipophilicity of the compounds, and inclusion of hydrogen bond acceptor strength and steric parameters as descriptors led to a QSAR equation with remarkably increased predictive power.
Abstract: A series of 4-acyl-3-pyrazolone derivatives with a 3-substituted 2-hydroxy-3-aminopropyl chain attached to pyrazole N-1 (7−20) as well as isomeric 4-acyl-5-(3-substituted 3-amino-2-hydroxypropoxy)pyrazole derivatives (5, 6) were synthesized, and their multidrug resistance (MDR)-modulating activity was measured using the daunomycin efflux assay. Reaction of N1-substituted 4-acyl-3-pyrazolones (tautomer to 4-acyl-5-hydroxypyrazoles) with excessive epichlorohydrin and successive treatment with an appropriate amine resulted in N-alkylation and thus afforded the target pyrazolone derivatives 7−20. In contrast, O-alkylation occurred upon reaction with 1 equiv of epichlorohydrin and subsequent treatment with amine leading to the corresponding 4-acyl-5-pyrazolyl ethers 5 and 6. QSAR studies showed a good correlation of MDR-modulating activity with lipophilicity of the compounds. Inclusion of hydrogen bond acceptor strength and steric parameters as descriptors led to a QSAR equation with remarkably increased predi...

77 citations


Journal ArticleDOI
TL;DR: The mixed functionality pyrazole/phenol ligand (2-hydroxyphenyl)bis(pyrazolyl)methane, L1OH, has been used to prepare a series of linear trimetallic systems with the general structural motif [M(3)(L1O)(4)](2+), where M = Mn(2+.
Abstract: The mixed functionality pyrazole/phenol ligand (2-hydroxyphenyl)bis(pyrazolyl)methane, L1OH, has been used to prepare a series of linear trimetallic systems with the general structural motif [M3(L1...

71 citations


Patent
12 Jun 1998
TL;DR: Novel pyridyl or pyrimidinyl substituted pyrazole and pyrazoline compounds and compositions for use in therapy were presented in this article, where they were used in therapy.
Abstract: Novel pyridyl or pyrimidinyl substituted pyrazole and pyrazoline compounds and compositions for use in therapy.

70 citations


Journal ArticleDOI
TL;DR: In this article, the pyrazole was added to the allenylidene complex to afford the structure of the allene of 1, and the reaction was shown to be reversible.

66 citations


Journal ArticleDOI
Qi Han1, C.-H. Chang1, Renhua Li1, Y. Ru1, Prabhakar K. Jadhav1, Patrick Y.S. Lam1 
TL;DR: The X-ray structure of HIVPR.10A complex confirms that the two pyrazole rings of 10A form bidentate hydrogen bonds with the side-chain oxygen (C=O) and backbone nitrogen (N-H) of Asp30/30' of HIV PR.
Abstract: Highly potent HIV-1 protease (HIVPR) inhibitors have been designed and synthesized by introducing bidentate hydrogen-bonding oxime and pyrazole groups at the meta-position of the phenyl ring on the P2/P2' substituents of cyclic ureas. Nonsymmetrical cyclic ureas incorporating 3(1H)-pyrazolylbenzyl as P2 and hydrophilic functionalities as P2' show potent protease inhibition and antiviral activities against HIV and have good oral bioavailabilities. The X-ray structure of HIVPR.10A complex confirms that the two pyrazole rings of 10A form bidentate hydrogen bonds with the side-chain oxygen (C=O) and backbone nitrogen (N-H) of Asp30/30' of HIVPR.

Journal ArticleDOI
TL;DR: In this article, three different approaches are used to discuss the possible analogy between the [1,5] hydrogen shift in cyclopentadiene and the prototropy in 1H-pyrazole.
Abstract: Three different approaches are used to discuss the possible analogy between the [1,5] hydrogen shift in cyclopentadiene and the prototropy in 1H-pyrazole. In the first, a series of NH→HN hydrogen shifts in cyclic conjugated molecules are considered demonstrating that the case of pyrazole is not intrinsically different from the other systems which are unrelated to [1,5] H shifts. The second approach compares pyrazole and cyclopentadiene with their open-ring structures, pentadiene and aminoazadiene, proving that the N–N bond is essential to describe pyrazole while the C(sp3)–C(sp2) bond in cyclopentadiene can be considered as a perturbation. Finally, the third approach is a study of cyclopentadienide and pyrazolide anions as hydrogen-bond acceptors, the first one being a π-acceptor while the second one is a σ-acceptor through the nitrogen lone pair. The conclusion is that N(sp2)–N(sp2) migrations of hydrogen in aromatic azoles are outside the Woodward–Hoffmann domain of application.

Patent
03 Aug 1998
TL;DR: In this paper, the authors considered conditions in which R1, R2 and R3 may not all simultaneously be hydrogen, and when R1 and R2 are hydrogen, R 3 may not be meta-CF3; and R4, R5 and R6 are, independently, hydrogen, halogen, nitro, cyano, C1-10 carboalkoxy, C 1-10 haloalkoxy and C6-12 aryl.
Abstract: Compounds of formula (I) wherein: R1, R2 and R3 are, independently, hydrogen, nitro, cyano, C1-10 haloalkoxy, amino, C1-10 alkylamino, sulfo, sulfamoyl, C1-10 alkylsulfonamido, C2-10 alkylcarboxamido C2-10 alkanoyl, C1-10 alkylsulfonyl, C1-10 haloalkylsulfonyl, C1-10 carboxyl, C1-10 haloalkyl and C6-12 aryl; with the provisos: (1) that R1, R2 and R3 may not all simultaneously be hydrogen, and (2) when R1 and R2 are hydrogen, R3 may not be meta-CF3; R4, R5 and R6 are, independently , hydrogen, halogen, nitro, cyano, C1-10 carboalkoxy, C1-10 haloalkoxy, amino C1-10 alkylamino, sulfo, sulfamoyl, C1-10 alkylsulfonamido, C2-10 alkylcarboxamido C2-10 alkanoyl, C1-10 alkylsulfonyl, C1-10 haloalkylsulfonyl, C1-10 carboxyl, C1-10 haloalkyl, C1-10 alkyl and C6-12 aryl; R7 is hydrogen , metal cation, acetylamido, alkoxyacetoyl or a related moiety which delivers the carboxylate in vivo; and X, Y and Z may form a C3-13 carbocyclic ring, oxazole, isoxazole, thiazole, isothiazole, furan, thiophene, 2H-pyrrole, pyrrole, 2-pyrroline, 3-pyrroline, imidazole, pyrazole, 1,2,3-oxadiazole or 1,2,3-triazole bound to the carbon skeleton; or pharmaceutically acceptable salts thereof useful in the treatment of disorders associated with smooth muscle contraction via potassium channel and chloride channel modulation.

Journal ArticleDOI
TL;DR: In this paper, a new family of enantiomerically pure pyrazoles with a variety of substitutions on a key stereogenic center was synthesized from (R)-(+)-pulegone by a straightforward, large-scale route involving initial construction of the pyrazole ring via formylation/dehydration with hydrazine followed by ozonolysis to yield a readily functionalized ketone.

Journal ArticleDOI
TL;DR: In this article, the Pd-catalyzed hydrosilylation of norbornene with trichlorosilane using different chiral ferrocenyl ligands containing a phosphine and a pyrazole as donors was studied.
Abstract: The Pd-catalyzed hydrosilylation of norbornene with trichlorosilane using different chiral ferrocenyl ligands containing a phosphine and a pyrazole as donors was studied. Both steric and electronic factors affect stereoselectivity in this system. The combination of a sterically bulky pyrazole substituent with a π-acidic phosphine leads to an enantioselectivity of >99.5% ee. Important substrate electronic effects on stereoselectivity were observed using para-substituted styrenes.

Journal ArticleDOI
TL;DR: A series of nitrido-ruthenium (VI) and -osmium(VI) complexes containing chelating di-, tri- and tetra-anionic ligands was synthesized by ligand substitution reaction in methanol under room conditions in the presence of 2,6-dimethylpyridine as mentioned in this paper.
Abstract: A series of nitrido-ruthenium(VI) and -osmium(VI) complexes containing chelating di-, tri- and tetra-anionic ligands was synthesized by ligand substitution reaction in methanol under room conditions in the presence of 2,6-dimethylpyridine. All the newly prepared complexes are air-stable diamagnetic solids. The crystal structures of seven complexes have been established by X-ray crystallography. The RuN (1.615–1.594 A) and the OsN (1.612–1.621 A) bond distances are rather insensitive to the electron-donating power of the auxiliary ligands. All the nitridoruthenium(VI) complexes react spontaneously with triphenylphosphine, and the intermediate [RuIV(NPPh3)L1(py)Cl] has been isolated and characterized spectroscopically for the reaction with [RuVIN(L1)Cl]. However, for those nitridoruthenium(VI) complexes bearing the tri- (L2)3– and tetra-anionic (L3,4)4– ligands, the phosphiniminatoruthenium(IV) intermediate undergoes further reaction with pyrazole to generate a bis(pyrazole)ruthenium(IV) complex as the product.

Patent
16 Apr 1998
TL;DR: The compound of formula I for the prevention of inflammation related cardiovascular disorders, providing the use of the compound of the formula I is not in combination with a 5-lipoxygenase inhibitor, a leukotriene-A-hydrolase inhibitor or a B4-receptor antagonist.
Abstract: The compound of formula I for the prevention of inflammation related cardiovascular disorders, providing the use of the compound of formula I is not in combination with a 5-lipoxygenase inhibitor, a leukotriene-A-hydrolase inhibitor or a leukotriene-B4-receptor antagonist. In the compound of formula I: A is selected from partially unsaturated or unsaturated heterocyclyl and partially unsaturated or unsaturated carbocyclic rings; R1 is selected from heterocyclyl, cycloalkyl, cycloalkenyl and aryl and is optionally substituted; R2 is a methyl or amino; R3 is a radical selected from hydrido, halo, alkyl, alkenyl, alkynyl, oxo, cyano, carboxyl, cyanoalkyl, heterocyclyloxy, alkyloxy, alkylthio, alkylcarbonyl, cycloalkyl, aryl, haloalkyl, heterocyclyl, cycloalkenyl, aralkyl, heterocyclylalkyl, acyl, alkylthioalkyl, hydroxyalkyl, alkoxycarbonyl, arylcarbonyl, aralkylcarbonyl, aralkenyl, alkoxyalkyl, arylthioalkyl, aryloxyalkyl, aralkylthioalkyl, aralkoxyalkyl, alkoxyaralkoxyalkyl, alkoxycarbonylalkyl, aminocarbonyl, aminocarbonylalkyl, alkylaminocarbonyl, N-arylaminocarbonyl, N-alkyl-N-arylaminocarbonyl, alkylaminocarbonylalkyl, carboxyalkyl, N-arylamino, N-aralkylamino, N-alkyl-N-aralkylamino, N-alkyl-N-arylamino, aminoalkyl, N-arylaminoalkyl, N-aralkylaminoalkyl, N-alkyl-N-aralkylaminoalkyl, N-alkyl-N-arylaminoalkyl, aryloxy, aralkoxy, arylthio, aralkylthio, alkylsulfinyl, alkylsulfonyl, aminosulfonyl, alkylaminosulfonyl, N-arylaminosulfonyl, arylsulfonyl, N-alkyl-N-arylaminosulfonyl. Providing that if A is imidazole, the sulfonylphenyl group is on the nitrogen atom that is the third ring atom, if A is pyrazole the sulfonylphenyl group is not substituted on a pyrazole ring nitrogen atom or the pyrazole ring carbon atom that is the fifth ring atom, if A is oxazole the sulfonylphenyl group is not substituted on the oxazole ring carbon atom that is the fifth ring atom, if A is isoxazole the sulfonylphenyl group is not substituted on the isoxazale ring carbon atom that is the third or fourth ring atom, if A is thiazole the sulfonylphenyl group is not substituted on the thiazole ring carbon that is the fourth or fifth ring atom.

Journal ArticleDOI
TL;DR: VOCl3 reacts with pyrazolylpyridines to give new six-coordinate vanadium oxoalkoxo complexes that catalyze the epoxidation of allylic alcohols and unfunctionalized olefins in the presence of tBuOOH.
Abstract: VOCl3 reacts with pyrazolylpyridines in the presence of tBuOH to give new six-coordinate vanadium oxoalkoxo complexes. Changing from tBuOH to tBuOOH does not lead to the corresponding tbutylperoxo complexes but to oxidation of Cl-, which finally results in chlorination of the pyrazole fragment of the chelate ligand. These new V(V) complexes catalyze the epoxidation of allylic alcohols and unfunctionalized olefins in the presence of tBuOOH.

Journal ArticleDOI
TL;DR: In this article, the coupling of 1,3-keto esters, 1, 3-diketones, acyl(aroyl)pyruvic esters and 2-arylhydrazones with pentafluorophenyl substituents leads to cinnolone derivatives.

Patent
06 Oct 1998
TL;DR: In this paper, chemical compounds that are derivatives of indeno[1,2-c]-, naphtho[1 2c]- and benzo[6,7]cyclohepta[1.2]-pyrazole are identified as inhibitors of tyrosine kinase activity.
Abstract: Chemical compounds that are derivatives of indeno[1,2-c]-, naphtho[1,2-c]- and benzo[6,7]cyclohepta[1,2-c]pyrazole are inhibitors of tyrosine kinase activity. Several of the tyrosine kinases, whose activity is inhibited by these chemical compounds, are involved in hyperproliferative, angiogenic or in vascular hyperpermeability processes. Thus, these chemical compounds can ameliorate disease states where tumor formation, metastasis, angiogenesis, vascular hyperpermeability or endothelial cell proliferation is a factor.

Journal ArticleDOI
TL;DR: Microwave assisted ring opening of (R )-styrene epoxide with pyrazole and imidazole gives the corresponding ( R )-configurated (1-phenyl)(2-azolyl)ethanols in high yields.

Journal ArticleDOI
TL;DR: In this paper, the complex formation between oxovanadium(IV) and several diazole derivatives was studied in aqueous solution by pH-potentiometric and spectroscopic (electron paramagnetic resonance and electronic absorption) techniques.

Journal ArticleDOI
TL;DR: A series of novel pyrazole carboxamides is disclosed that demonstrate strong immunosuppressant activity in rodent and human mixed leukocyte response (MLR) assays (IC50 < 1 microM).

Journal ArticleDOI
TL;DR: In this paper, a new general method for the synthesis of 1-acyl-3-hydroxy-1H-pyrazoles 5a-f and related derivatives 5g-i starting from 4-ethoxymethylene-2-phenyloxazol-5(4H)-one (1) and hydrazides, 4phenylsemicarbazide, 4-phenylonthiosemicarazide and benzyl carbazate in boiling dioxane is described.
Abstract: A new general method for the synthesis of 1-acyl-3-hydroxy-1H-pyrazoles 5a–f and related derivatives 5g–i starting from 4-ethoxymethylene-2-phenyloxazol-5(4H)-one (1) and hydrazides, 4-phenylsemicarbazide, 4-phenylthiosemicarbazide and benzyl carbazate in boiling dioxane is described. The method includes a migration of an acyl or related unit. The X-ray study and NMR spectroscopic examination confirmed the structure of the products. A one-pot synthesis of N,N′-diacylhydrazines from hydrazides by the assistance of oxazolone 1 is also presented.

Journal ArticleDOI
TL;DR: In this article, an effective and convenient protocol has been developed for the conversion of d -glucose and 6-O-α-d-glucopyranosyl- d -fructose (palatinose®, isomaltulose) into 5-[(1′S)-1′,2′-dihydroxyethyl]-1-phenylpyrazole-3-carboxaldehyde (4) and 5-[ (1S)-2-(α- d-glocopyranoyloxy)-1-hydroxethyl])-1

Journal ArticleDOI
TL;DR: In this paper, the tetrahedral ZnN 2 S 2 coordination was shown to be applicable to all monomeric zinc complexes, irrespective of the ring size (5,6,8) which is enforced on the chelate ligand, even at the expense of unused ligand donor atoms.

Patent
24 Jun 1998
TL;DR: The bis-pyrazole aza compounds have the formula (I): ##STR1## wherein R 1, R 1 ', R 2, R 2 ', R 3 and R 3'are the same or different, and are each, independently of each other, H, a straight, branched or cyclic alkyl group having 1 to 6 carbon atoms.
Abstract: The new bis-pyrazole aza compounds have the formula (I): ##STR1## wherein R 1 , R 1 ', R 2 , R 2 ', R 3 and R 3 ' are the same or different, and are each, independently of each other, H, a straight, branched or cyclic alkyl group having 1 to 6 carbon atoms, a straight chain or branched monohydroxyalkyl group or polyhydroxyalkyl group with 1 to 6 carbon atoms, a straight or branched alkoxyalkyl group with 2 to 6 carbon atoms, a straight or branched monoaminoalkyl group or polyaminoalkyl group with 2 to 6 carbon atoms, or an unsubstituted aromatic or heteroaromatic ring, or a substituted aromatic or heteroaromatic ring having one or more halogen, a C 1 - to C 4 -alkyl group, a nitro group, a sulfonic acid group, a carboxylic acid group or a C 1 - to C 4 -alkoxy substituent, or an unsubstituted benzyl group, or a benzyl group substituted with one or more halogen atom, a hydroxy group, a C 1 - to C 4 - alkyl group, a nitro group or a C 1 - to C 4 -alkyoxy group, or R 1 together with R 2 and/or R 1 ' together with R 2 ' represent a C 3 -diradical bridge. Hair dye compositions containing these new dye compounds and methods of making them are also disclosed.

Journal ArticleDOI
TL;DR: In this paper, the reaction of 6-amino 1,4,5,6-tetrahydro-5-imino-3-methyl-1-phenyl-4 (pchlorophenyl) pyrazolo [4', 3' : 5,6]-pyrano [2,3-d] pyrimidine (3) with different reagents.
Abstract: 3-Substituted 1,2,4-triazole derivatives (5, 9, 13, 16b, 19), pyrimidinium salts (21), triazines (24), and aryl methylene hydrazono pyrazolopyrano-pyrimidine (27a,b) which are rearranged in basic medium to 30a,b, were afforded via the reaction of 6-amino 1,4,5,6-tetrahydro-5-imino-3-methyl-1-phenyl-4 (pchlorophenyl) pyrazolo [4', 3' : 5,6]-pyrano [2,3-d] pyrimidine (3) with different reagents.

Patent
11 Jun 1998
TL;DR: Tricyclic pyrrole or pyrazole derivatives represented by general formula (I) or pharmaceutically acceptable salts thereof, which have high selectivity and affinity for 5-HT2c receptors and are useful in treating central nervous system diseases such as sexual function disorder, appetite regulation disorder, anxiety, depression or sleep disturbance as discussed by the authors.
Abstract: Tricyclic pyrrole or pyrazole derivatives represented by general formula (I) or pharmaceutically acceptable salts thereof, which have high selectivity and affinity for 5-HT2c receptors and are useful in treating central nervous system diseases such as sexual function disorder, appetite regulation disorder, anxiety, depression or sleep disturbance. In said formula, the ring Y represents an unsaturated 5-membered ring optionally having 1 to 3 heteroatoms of one or more types selected from the group consisting of nitrogen, oxygen and sulfur or an unsaturated 6-membered ring having 1 or 2 nitrogen atoms; X represents a bond or carbon; --- represents a double or single bond; V represents nitrogen or CH; and A represents linear or branched lower alkylene optionally substituted by halogeno or cycloalkyl.

Journal ArticleDOI
TL;DR: In this article, the HOMA model was applied to molecular geometry of the title compounds enriched by the data for pyrazoles retrieved from CSD and from RHF/6-311G∗∗ ab-initio calculations.