Search results for "Pyrazole"
showing 10 items of 315 documents
ChemInform Abstract: Mass Spectrometry of 3,4-Dihydroquinazolin-4-ones of Pharmaceutical Interest. Part 3. Electron Ionization Mass Spectra of 2-Subs…
2010
The fragmentation reactions induced by electron impact of eighteen title compounds has been investigated with the aid of low beam energy spectra (14 eV, nom. value), metastable ion detection, high resolution measurements and labelling experiments. The loss of the 4-carbonyl oxygen together with the 3-substituent, which constitutes a characteristic fragmentation route of 3-aryl and 3-heteroaromatic substituted-4(3H)-quinazolinones, is again observed, but the presence of a carboxyethyl group at the 4′-position of the pyrazole ring is responsible of an anomalous loss of 47 daltons from the molecular ion. Lastly, a comparison with the previously described behaviour of 3-(5′-isoxazolyl) derivati…
Hypothalamic CB1 cannabinoid receptors regulate energy balance in mice.
2012
Cannabinoid type 1 (CB(1)) receptor activation is generally considered a powerful orexigenic signal and inhibition of the endocannabinoid system is beneficial for the treatment of obesity and related metabolic diseases. The hypothalamus plays a critical role in regulating energy balance by modulating both food intake and energy expenditure. Although CB(1) receptor signaling has been implicated in the modulation of both these mechanisms, a complete understanding of its role in the hypothalamus is still lacking. Here we combined a genetic approach with the use of adeno-associated viral vectors to delete the CB(1) receptor gene in the adult mouse hypothalamus and assessed the impact of such ma…
4-(4-Fluorophenyl)-3-(pyridin-4-yl)-1-(2,4,6-trichlorophenyl)-1H-pyrazol-5-amine
2012
In the title compound, C20H12Cl3FN4, the pyrazole ring forms dihedral angles of 47.51 (9), 47.37 (9) and 74.37 (9)° with the directly attached 4-fluorophenyl, pyridine and 2,4,6-trichlorophenyl rings, respectively. Only one of the two amino H atoms is involved in hydrogen bonding. The crystal packing is characterized by N—H...N hydrogen bonds, which result in infinite chains parallel to the c axis.
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 […
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…
Efficient Green Light-Emitting Electrochemical Cells Based on Ionic Iridium Complexes with Sulfone-Containing Cyclometalating Ligands
2013
A new approach to obtain green-emitting iridiumA complexes is described. The synthetic approach consists of introducing a methylsulfone electron-withdrawing substituent into a 4-phenylpyrazole cyclometalating ligand in order to stabilize the highest- occupied molecular orbital (HOMO). Six new complexes have been synthe- sized incorporating the conjugate base of 1-(4-(methylsulfonyl)phenyl)-1 H- pyrazole as the cyclometalating ligand. The complexes show green emission and very high photoluminescence quantum yields in both diluted and concentrated films. When used as the main active component in light-emit- ting electrochemical cells (LECs), green electroluminance is observed. High efficienci…
Synthesis and in vitro antileukemic activity of new 4-triazenopyrazole derivatives
2003
Several new 4-(3,3-dimethyltriazeno)-5-benzamidopyrazole derivatives were prepared by reacting 4-diazo-5-benzamidopyrazole derivatives with dimethylamine. The compounds were tested at 10 microM for their vitro antileukemic activity against K562 (Human chronic myelogenous leukemia) and Raji (human Burkitt limphoma ) cell lines. Dacarbazine and methotrexate were used for comparative purpose. The 3-methyl-4-(3,3-dimethyltriazeno)-5-(substituted benzamido)pyrazoles, bearing the pyrazole nucleus free at 1 position, resulted more active than the 1-(substituted phenyl)-3-methyl-4-(3,3-dimethyltriazeno)-5-benzamidopyrazoles. Dacarbazine at 10 microM showed no activity in the above tests. The observ…
The hMTH1 paradox: antioxidants recommended in cancer?
2014
Summary Activated Ras GTPase signalling is a critical driver of oncogenic transformation and malignant disease. Cellular models of RAS-dependent cancers have been used to identify experimental small-molecules, such as SCH51344, but their molecular mechanism of action remains generally enigmatic. Here, using a chemical proteomic approach we identify the target of SCH51344 as the human mutT homologue MTH1, a nucleotide pool sanitising enzyme. Loss-of-function of MTH1 impaired growth of KRAS tumour cells whereas MTH1 overexpression mitigated sensitivity toward SCH51344. Searching for more drug-like inhibitors, we identified the kinase inhibitor crizotinib as a nanomolar suppressor of MTH1 acti…
Involvement of CB1 and CB2 receptors in the modulation of cholinergic neurotransmission in mouse gastric preparations.
2007
Abstract While most of the studies concerning the role of cannabinoids on gastric motility have focused the attention on the gastric emptying in in vivo animal models, there is little information about the cannabinoid peripheral influence in the stomach. In addition, the functional features of CB2 receptors in the gastrointestinal tract have been poorly characterized. The purpose of the present study was to investigate the effects of cannabinoid drugs on the excitatory cholinergic and inhibitory non-adrenergic non-cholinergic (NANC) neurotransmission in mouse isolated gastric preparations. Intraluminal pressure from isolated whole stomach was recorded and mechanical responses induced by ele…
Remarkable Steric Effects and Influence of Monodentate Axial Ligands L on the Spin-Crossover Properties of trans-[FeII(N4 ligand)L] Complexes
2007
Iron(II) complexes obtained from tetradentate, rigid, linear N4 ligands have been investigated to appraise the influence of steric effects and the impact of trans-coordinated anions on the spin-transition behavior. As expected, the well-designed ligands embrace the metal center, resulting in octahedral iron(II) complexes where the basal plane is fully occupied by the pyridine/pyrazole N4 ligand, while anions or solvent molecules are exclusively axially coordinated. Precursor complexes, namely, [Fe(bpzbpy)(MeOH)2](BF4)2 (where bpzbpy symbolizes the ligand 6,6'-bis(N-pyrazolylmethyl)-2,2'-bipyridine) and [Fe(mbpzbpy)(MeOH)2](BF4)2 (where mbpzbpy symbolizes the ligand 6,6'-bis(3,5-dimethyl-N-p…