Showing papers on "Pyrazoline published in 2009"

Biological activities of pyrazoline derivatives--a recent development.

Abstract: Pyrazolines are well known and important nitrogen containing 5-membered heterocyclic compounds and various methods have been worked out for their synthesis. Numerous pyrazoline derivatives have been found to possess considerable biological activities, which stimulated the research activity in this field. They have several prominent effects, such as antimicrobial, antimycobacterial, antifungal, antiamoebic, anti-inflammatory, analgesic, antidepressant and anticancer activities. They also possess some potent receptor selective biological activity like Nitric oxide synthase (NOS) inhibitor and Cannabinoid CB1 receptor antagonists activity. 4,5-dihydro-1H- pyrazolines seem to be the most frequently studied pyrazoline type compounds. As a result, a large number of such pyrazolines using different synthetic methods for their preparation have been described in the chemistry literature. The present review provides an insight view to pyrazolines synthesis and its biological activities along with the compilation of recent patents on pyrazolines.

Experimental and density functional studies on 4-(4-cyanobenzylideneamino)antipyrine

Abstract: 4-(4-cyanobenzylideneamino)antipyrine (CBAP) has been synthesized and characterized by elemental analysis, FT-IR, UV-VIS and X-ray single crystal diffraction techniques. Crystallographic study reveals that the compound adopts trans configuration about the Schiff base imine double bond. The substituted p-cyanophenyl ring indirectly linked to the pyrazoline ring by the C=N double bond is almost coplanar with the pyrazole ring, whereas the phenyl ring directly attached to the pyrazoline ring forms an effective dihedral angle. Density functional calculations have been carried out to optimize and to characterize the title compound by using B3LYP method at 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structural parameters and the theoretical vibrational frequencies show good agreement with experimental values. On the basis of theoretical vibrational analyses, the thermodynamic properties (standard heat capacities, standard entropies, and standard ent...

Bioorthogonal Ligation in the Spotlight

Abstract: The light-induced formation of a covalent bond between an alkene group and a tetrazole moiety has been used for the selective labeling of proteins in vitro and in live cells. This bioorthogonal ligation initiated by brief irradiation with UV light leads to a fluorescent pyrazoline adduct (see scheme).

Design, synthesis, and in-vivo pharmacological screening of N,3-(substituted diphenyl)-5-phenyl-1H-pyrazoline-1-carbothioamide derivatives.

Abstract: Various 3,5-(substituted diphenyl)-4,5-dihydro-pyrazole-1-carbothioic acid phenylamides were synthesized starting from substituted acetophenones. Structures of the compounds were confirmed on the basis of spectral data. The compounds were evaluated for their anticonvulsant and antidepressant activity. Interestingly, out of 26 compounds, four (3f, 3g, 3t, and 3u) were found to protect 100% of the animals in the MES screen at a dose of 25 mg/kg. They were also found to have appreciable anticonvulsant activity in scPTZ screen. Two compounds, 3j and 3o, significantly reduced the duration of the immobility time at 25 mg/kg dose, when compared to control.

Synthesis and Antimicrobial Studies of Some Novel Pyrazoline and Isoxazoline Derivatives

Abstract: A new series of 1H-3-(4’-substituted phenyl)-5-(6’’-methoxy napthaline)-2-pyrazolines (4a-e) and 1H-3-(4’-substituted phenyl)-5-(6’’-methoxynapthaline)-2-isoxazolines (5a-e) were synthesized by reacting 1-(4’-substituted phenyl)-3-(6’’-methoxynapthaline)-2-propene-1-one (3a-e) with hydrazine hydrate and hydroxylamine hydrochloride respectively. All these compounds were characterized by means of their IR, 1H NMR, spectroscopic data and microanalysis. All the synthesized products were evaluated for their antimicrobial activity. All the compounds exhibited significant to moderate antimicrobial activity.

A Divergent Approach to the Synthesis of 3-Substituted-2-pyrazolines: Suzuki Cross-Coupling of 3-Sulfonyloxy-2-pyrazolines

Abstract: The efficient Suzuki cross-coupling of pyrazoline nonaflates with organoboron reagents was achieved to afford diverse 3-substituted-2-pyrazolines in excellent yield. The nonaflates displayed improved reactivity over the corresponding triflates and smoothly coupled to a variety of aryl- and heteroarylboronic acids. This process and its broad scope constitute a rapid, divergent strategy for the synthesis of elaborated 2-pyrazolines that are not readily obtained via conventional methods.

Synthesis, Spectral Studies and Antiamoebic Activity of New 1-N-Substituted Thiocarbamoyl-3-phenyl-2-pyrazolines.

Abstract: Thirty new pyrazoline derivatives were synthesized by cyclization of Mannich bases with thiosemicarbazides being substituted by different cyclic and aromatic amines. The structures of the compounds were elucidated by elemental analyses, UV, IR, 1 H and 13 C NMR and ESI-MS spectral data. The in vitro antiamoebic activity was evaluated against Entamoeba histolytica in comparison with metronidazole used as reference substance. Out of the 30 compounds screened for antiamoebic activity, 10 ( 5 , 6 , 15 , 18 , 25 – 30 ) were found to be better inhibitors of E. histolytica since they showed lesser IC 50 values than metronidazole. The preliminary results indicated that the presence of 3-chloro or 3-bromo substituent on the phenyl ring at position 3 of the pyrazoline ring enhanced the antiamoebic activity as compared to unsubstituted phenyl ring. The study suggests that the preliminary activity of these compounds may further be explored for the development of new targets for amoebiasis.

Synthesis, spectroscopic, antimicrobial and anti-inflammatory studies of 5(2′-hydroxyphenyl)-3-(4-x-phenyl)pyrazolinates of copper(II) and their addition complexes with donor ligands

Abstract: Complexes of copper(II) with 5(2′-hydroxyphenyl)-3-(4-x-phenyl)pyrazolines, (C15H12N2OX)2Cu [X =–H,–Cl,–CH3,–OCH3] have been synthesized with their addition complexes with 2,2′-bipyridine, 1,10-phenanthroline and triphenylphosphine. The complexes were characterized by elemental analyses, molecular weight measurement, magnetic, conductivity measurement, IR, electronic, 31P NMR, ESR and FAB mass spectra. The complexes were examined for crystalline/amorphous nature through XRD. Square-planar geometry around copper(II) is suggested with two bidentate pyrazoline ligands. In the additional complexes pyrazoline is monodentate. The bidentate and monodentate behavior of pyrazoline ligands was confirmed by IR and 31P NMR spectral data. All complexes were tested for in vitro antibacterial and antifungal activity and exhibit very good antibacterial and antifungal activity; coordination has a pronounced effect on the microbial activities. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic...

Synthesis and antimicrobial evaluation of some new pyrazole, pyrazoline and chromeno[3,4-c]pyrazole derivatives

Abstract: Some new pyrazole-5-carbonitrile derivatives 8, 9 and pyrazole-5-carboxamide 13 were synthesized by the cycloaddition reaction of nitrilimines 3, 4 to α-cyanocinnamonitriles 5a-f and α-cyanocinnamamide 12a, b respectively. On the other hand 3, 4 add to ethyl α-cyanocinnamate 14a-f to give ethyl 2-pyrazoline-5-carboxylate derivatives 15, 16. Also, cycloaddition of 3, 4 to 3-cyanocoumarin 19a or 3-phenylsulphonylcoumarin 19b or 3-bromocoumarin 19c give chromeno[3,4-c]pyrazol-4(3H)-one derivatives 20. In the same direction, the cycloaddition of 3, 4 to 3-acetylcoumarin 22 and 3-benzoylcoumarin 23 gives the corresponding dihydrochromeno[3,4-] pyrazol-4(3H)-one 24 and 25 respectively. Oxidation of 24 and 25 give 20. Most of the prepared compounds showed good to moderate antibacterial and antifungal activities.

Synthesis, spectral and antimicrobial studies of chloroantimony(III)di[3(2′-hydroxyphenyl)-5-(4-substitutedphenyl)pyrazolinates]

Abstract: Dichloroantimony(III) pyrazolinates and chloroantimony(III) dipyrazolinates of the type SbCl2(C15H12N2OX) and SbCl(C15H12N2OX)2 [where C15H12N2OX = 3(2′-hydroxyphenyl)-5-(4-X-phenyl)pyrazoline, X=H in1 and5;–CH3 in2 and6;–OCH3 in3 and7 and–Cl in4 and8] have been synthesized by reaction of SbCl3 and sodium salt of pyrazolines in 1 : 1 and 1 : 2 molar ratio in anhydrous benzene at elevated temperature. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sb), molecular weight measurement and spectral studies [IR and1H and13C NMR]. The free pyrazoline and some dichloroantimony(III) pyrazolinates and chloroantimony(III) dipyrazolinates have been screened for antibacterial and antifungal activities, with some dichloroantimony(III) pyrazolinates and chloroantimony(III) dipyrazolinates exhibiting higher antibacterial and antifungal effects than free pyrazoline and some antibiotics.

Synthesis of Novel Thiazolone-Based Compounds Containing Pyrazoline Moiety and Evaluation of Their Anticancer Activity.

Abstract: To examine the anticancer activity several novel thiazolone-based compounds containing 5-aryl-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl framework were obtained. Reaction of 5-aryl-3-phenyl-4,5-dihydropyrazole with 4-thioxo-2-thiazolidinone or 2-carbethoxymethylthio-2-thiazoline-4-one yielded starting 4- (1 and 2) or 2-substituted (11 and 12) thiazolones which were utilized in Knoevenagel condensation for obtaining a series of 5-arylidene derivatives 3–10, 13–18. Alternatively 11, 12 and their 5-arylidene derivatives were synthesized by means of 3-phenyl-5-aryl-1-thiocarbamoyl-2-pyrazoline as S,N-binucleophile via [2 + 3]-cyclocondensation approach. The structures of compounds were determined by 1H, 13C NMR, LC–MS, EI-MS and X-ray analysis. The in vitro anticancer activity of synthesized compounds were tested by the National Cancer Institute and most of them displayed anticancer activity on leukemia, melanoma, lung, colon, CNS, ovarian, renal, prostate and breast cancer cell lines. Relations between structure and activity are discussed, the most efficient anticancer compound 16 was found to be active with selective influence on colon cancer cell lines, especially on HT 29 (log GI50 = −6.37).

Synthesis and Characterization of a Novel 2-Pyrazoline

Abstract: Reaction of dibenzalacetone with hydrazine hydrate and formic acid yielded a novel 2-pyrazoline 1 , characterized by ESI-MS, FT-IR, UV, 1 HNMR and 13 CNMR data and microanalysis. Keywords: dibenzalacetone; hydrazine hydrate; pyrazoline; 5-phenyl-3-[( E )-2-phenyl-vinyl]-4,5-dihydro-1 H -pyrazole-1-carbaldehyde; fluorescence Introduction Substituted pyrazolines are useful in pharmaceutical and agrochemical research. Pyrazoline derivatives with a phenyl group at the 5-position possess good film-forming properties, exhibit excellent characteristics of blue photoluminescence and electroluminescence [1]. Pyrazolines are also used as optical brighteners and whiteners. Pyrazolines display various biological activities such as antimicrobial [2], antifungal [3], antidepressant [4], immunosuppressive [5], anticonvulsant [6], anti-tumor [7], antiamoebic [8], antibacterial [9] and antiinflammatory [10] activities. Syntheses of pyrazolines by reaction of α,β-unsaturated carbonyl compounds with diazoalkanes [11] or with hydrazine hydrate [12,13] were reported in literature. N-Substituted thiocarbamoyl-3,5-diphenyl-2-pyrazoline derivatives having NS donor, their palladium II complexes [14] and hydroxyl phenyl pyrazolines have also been synthesized [15]. The reaction of

Synthesis, spectral and biological investigations of 5(2′-hydroxyphenyl)-3-(4-substituted-phenyl) pyrazolinates of cobalt(II) and their addition complexes with N, P donor ligands

Abstract: 5(2′-Hydroxyphenyl)-3-(4-substituted-phenyl)pyrazolinates of cobalt(II) of the type (C15H12N2OX)2Co [here substituted group X is–H,–Cl,–CH3 or–OCH3] have been synthesized by reaction of anhydrous cobalt(II)chloride with the sodium salt of the pyrazolines in 1 : 2 molar ratio. Their addition complexes with N and P donor ligands [2, 2′-bipyridine, 1, 10-phenanthroline and triphenylphosphine] were prepared in 1 : 1 molar ratio. The newly synthesized complexes were characterized by elemental analyses, molecular weight measurement, magnetic susceptibility, IR, electronic, 31P NMR and FAB mass spectra. All complexes are amorphous as determined by XRD. Tetrahedral geometry around cobalt(II) has been suggested, confirming the presence of two pyrazoline bidentate ligands, cobalt(II)5- (2′-hydroxyphenyl)-3-(4-substituted-phenyl)pyrazolinates. Upon ligand addition, pyrazoline changes to monodentate. The bidentate and monodentate behavior of pyrazoline ligands was confirmed by IR spectral data. The metal complexes an...

Zinc(II) 5-(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolinates and their adducts with N and P donor ligands: synthesis, spectral, biological, and anti-inflammatory investigations

Abstract: Synthesis, spectral, biological, and anti-inflammatory investigations of a series of complexes of zinc(II) with 5-(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolines of the type (C15H12N2OX)2Zn (where X =–H,–Cl,–CH3,–OCH3) are presented. The complexes were synthesized by reaction of anhydrous zinc(II) chloride with sodium salts of pyrazoline in 1 : 2 molar ratio. Adducts with N and P donor ligands (2,2′-bipyridine, 1,10-phenanthroline and triphenylphosphine) were prepared in 1 : 1 molar ratio. The complexes were characterized by elemental analyses, molecular weight, conductivity, IR, electronic, 1H, 13C, 31P NMR, and FAB mass spectral studies. All complexes are amorphous. Tetrahedral geometry around zinc confirms the presence of two bidentate pyrazoline ligands in zinc(II) 5-(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolinates. In adducts pyrazoline is monodentate. Bidentate and monodentate pyrazoline were confirmed by IR, 1H, 13C, and 31P NMR spectral data. All metal complexes were tested for their antibacterial and ...

Synthesis, spectroscopic, antibacterial and antifungal studies of nickel(II)5(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolinates and their addition complexes with N and P donor ligands

Abstract: A number of complexes of nickel(II) with 5(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolines of the type (C15H12N2O ··· X)2Ni [where X = H, Cl, CH3 and OCH3] were synthesized by the reaction of anhydrous nickel(II) chloride with sodium salts of pyrazoline in 1 : 2 molar ratio. Their addition complexes with 2,2′-bipyridine, 1,10-phenanthroline and triphenylphosphine were prepared in 1 : 1 molar ratio. These complexes were characterized by elemental analyses, molecular weight, magnetic, conductivity, IR, electronic, 1H, 13C, 31P NMR and FAB mass spectral data. All complexes are amorphous. Square planar geometry around nickel confirms the presence of two bidentate pyrazoline ligands in nickel(II)5(2′-hydroxyphenyl)-3-(4-X-phenyl)pyrazolinates. In the addition complexes pyrazoline is monodentate. Bidentate and monodentate pyrazoline was confirmed by IR, 1H, 13C and 31P NMR spectral data. All the metal complexes exhibit very good antibacterial and antifungal activity. Coordination of metal ion has pronounced effect ...