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1.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;46(3): 263-269, 15/mar. 2013. graf
Article de Anglais | LILACS | ID: lil-670895

RÉSUMÉ

The N-acylhydrazone (NAH) analogues N-methyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-785) and N-benzyl 2-thienylidene 3,4-benzoylhydrazine (LASSBio-786) were prepared from 2-thienylidene 3,4-methylenedioxybenzoylhydrazine (LASSBio-294). The ability of LASSBio-785 and LASSBio-786 to decrease central nervous system activity was investigated in male Swiss mice. LASSBio-785 or LASSBio-786 (30 mg/kg, ip) reduced locomotor activity from 209 ± 26 (control) to 140 ± 18 (P < 0.05) or 146 ± 15 crossings/min (P < 0.05), respectively. LASSBio-785 (15 or 30 mg/kg, iv) also reduced locomotor activity from 200 ± 15 to 116 ± 29 (P < 0.05) or 60 ± 16 crossings/min (P < 0.01), respectively. Likewise, LASSBio-786 (15 or 30 mg/kg, iv) reduced locomotor activity from 200 ± 15 to 127 ± 10 (P < 0.01) or 96 ± 14 crossings/min (P < 0.01), respectively. Pretreatment with flumazenil (20 mg/kg, ip) prevented the locomotor impairment induced by NAH analogues (15 mg/kg, iv), providing evidence that the benzodiazepine (BDZ) receptor is involved. This finding was supported by the structural similarity of NAH analogues to midazolam. However, LASSBio-785 showed weak binding to the BDZ receptor. LASSBio-785 or LASSBio-786 (30 mg/kg, ip, n = 10) increased pentobarbital-induced sleeping time from 42 ± 5 (DMSO) to 66 ± 6 (P < 0.05) or 75 ± 4 min (P < 0.05), respectively. The dose required to achieve 50% hypnosis (HD50) following iv injection of LASSBio-785 or LASSBio-786 was 15.8 or 9.5 mg/kg, respectively. These data suggest that both NAH analogues might be useful for the development of new neuroactive drugs for the treatment of insomnia or for use in conjunction with general anesthesia.


Sujet(s)
Animaux , Mâle , Souris , Hydrazines/pharmacologie , Hydrazones/pharmacologie , Hypnotiques et sédatifs/pharmacologie , Activité motrice/effets des médicaments et des substances chimiques , Récepteurs GABA/effets des médicaments et des substances chimiques , Thiophènes/pharmacologie , Hydrazines/composition chimique , Hydrazones/composition chimique , Récepteurs GABA/physiologie , Thiophènes/composition chimique
2.
Egyptian Journal of Chemistry. 2009; 52 (4): 491-506
de Anglais | IMEMR | ID: emr-135697

RÉSUMÉ

P-aminophenol was prepared by reduction of p-nitro-pheilol over nano sized nickel catalysts supported on two different supports, SiO2 and AI2O3 using hydrazine hydrate as hydrogen source. Several loadings of nano-sized Ni were used thus, 20, 5, and 2.5 wt% were prepared. XRD and ESR were employed to investigate the prepared catalysts. The Ni/AI2O3 support was found to be more effective and gives high durability. The catalytic activity of the reaction was found to be influenced by the crystallinity of the nickel in addition to the strain between nano sized nickel particles. The catalytic activity of the prepared catalysts was compared with commercial Raney nickel and showed higher activity especially at lower loading. During the reaction a detectable change of the color was observed from yellow to green to colorless, which enables us to propose a mechanism of this reaction


Sujet(s)
Hydrazines/composition chimique , Nanostructures , Nickel , Catalyse/effets des médicaments et des substances chimiques
4.
Indian J Exp Biol ; 2007 Nov; 45(11): 974-9
Article de Anglais | IMSEAR | ID: sea-62631

RÉSUMÉ

The aqueous extract of C. borivilianum (250 mg/kg for 7 days) significantly reverted the elevated levels of plasma glucose, triglycerides, cholesterol and serum corticosterone and also reduced the ulcer index, adrenal gland weight more as effectively as the standard drug (diazepam) in rats. At 125 mg/kg po, it showed a mild anti-stress activity. Under in vitro 1,1-diphenyl-2-picrylhydrazyl (DPPH*) free radical scavenging assay and lipid peroxidation assay the extract considerably inhibited, in a dose-dependent manner, the levels of DPPH* free radicals and thiobarbituric acid reactive substances, respectively thus showing significant antioxidant property. The results suggested that it could be used for the treatment of oxidative stress-induced disorders.


Sujet(s)
Glandes surrénales/effets des médicaments et des substances chimiques , Asparagaceae/composition chimique , Animaux , Antioxydants/isolement et purification , Dérivés du biphényle/composition chimique , Piégeurs de radicaux libres/isolement et purification , Hydrazines/composition chimique , Peroxydation lipidique/effets des médicaments et des substances chimiques , Mâle , Taille d'organe/effets des médicaments et des substances chimiques , Ulcère peptique/étiologie , Extraits de plantes/isolement et purification , Racines de plante/composition chimique , Poudres , Rats , Rat Wistar , Contention physique , Stress psychologique/sang
5.
Indian J Exp Biol ; 2007 Nov; 45(11): 968-73
Article de Anglais | IMSEAR | ID: sea-60037

RÉSUMÉ

Antioxidant potency of Indian grape cultivars varying in their skin color, seed and polyphenol content (Bangalore blue, Pandhari sahebi, Sharad seedless and Thompson seedless) and their components (whole grapes, pulp with skin and seeds) was examined as 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity using electron spin resonance spectrometry. The total polyphenols in Indian grapes ranged between 3-51%. Extracted polyphenols caused a concentration dependent and significant loss in DPPH radical signal, similar to known antioxidants-Vitamin C, catechin and procyanidin B3 used as references. Among seedless cultivars, polyphenols from Sharad was more potent as antioxidant than Thompson, showing IC50 values of 1250 +/- 30 and 2650 +/- 125 microg/ml, respectively. The inhibitory effect of polyphenols from seedless grape cultivars was as effective as that of seeded variety. The results indicate that polyphenols extracted from Indian grapes/ components (with /without seeds) exhibited free radical scavenging activity and their chemopreventive properties need to be exploited by in vivo model system.


Sujet(s)
Dérivés du biphényle/composition chimique , Spectroscopie de résonance de spin électronique , Flavonoïdes/composition chimique , Piégeurs de radicaux libres/composition chimique , Hydrazines/composition chimique , Inde , Phénols/composition chimique , Vitis/composition chimique
6.
Indian J Exp Biol ; 2007 Apr; 45(4): 376-84
Article de Anglais | IMSEAR | ID: sea-58318

RÉSUMÉ

In the present study, ethyl acetate, butanol and aqueous fractions derived from total methanol extract of Butea monosperma flowers were evaluated for radical scavenging activities using different in vitro models like reducing power assay, scavenging of 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical, nitric oxide radical, superoxide anion radical, hydroxyl radical and inhibition of erythrocyte hemolysis using 2, 2' azo-bis (amidinopropane) dihydrochloride (AAPH). Methanol extract along with its ethyl acetate and butanol fractions showed potent free radical scavenging activity, whereas aqueous fraction was found to be devoid of any radical scavenging properties. The observed activity could be due to the higher phenolic content in the extracts (16.1, 25.29, and 17.74% w/w in methanol extract, ethyl acetate and butanol fractions respectively). HPTLC fingerprint profile of the ethyl acetate and butanol fractions were developed which would serve as reference standard for quality control of the extracts.


Sujet(s)
Butan-1-ol/composition chimique , Acétates/composition chimique , Dérivés du biphényle/composition chimique , Butea/composition chimique , Érythrocytes/effets des médicaments et des substances chimiques , Fleurs/composition chimique , Piégeurs de radicaux libres/isolement et purification , Radicaux libres/composition chimique , Hémolyse/effets des médicaments et des substances chimiques , Hydrazines/composition chimique , Radical hydroxyle/composition chimique , Méthanol/composition chimique , Monoxyde d'azote/composition chimique , Oxydoréduction , Extraits de plantes/pharmacologie , Superoxydes/composition chimique , Eau/composition chimique
7.
Indian J Exp Biol ; 2006 Jun; 44(6): 468-73
Article de Anglais | IMSEAR | ID: sea-56425

RÉSUMÉ

Antioxidant potential of Aspergillus candidus MTCC 2202 broth filtrate extract was studied using different antioxidant models, whereas anti-inflammatory potential was studied using carrageenan-induced rat paw oedema model. The ethyl acetate extract at 1000 microg/ml showed maximum scavenging activity of the stable radical 1,1-diphenyl,2-picryl hydrazyl upto 96.65% (IC50=430.36 microg/ml) and scavenging of the radical cation, 2,2-azinobis-(3-ethylbenzothiazoline-6-sulphonate) upto 92.25% (IC50=606.29 microg/ml) at the same concentration. The extract had good reducing power, however showed moderate inhibition for conjugated dienes and thiobarbituric acid reactive acid substances (59.56 and 51.45%). The total phenolic content of various extracts of A. candidus broth filtrate was measured and a correlation between radical scavenging activities of extracts with total phenolic content was observed. The ethyl acetate extract (125 mg/kg ip) showed significant anti-inflammatory activity in carrageenan-induced rat paw oedema model. The exhibited antioxidant activity of ethyl acetate extract of A. candidus broth filtrate was comparable with BHA and ascorbic acid, while anti-inflammatory activity was comparable with standard diclofenac sodium.


Sujet(s)
Animaux , Anti-inflammatoires/pharmacologie , Antioxydants/composition chimique , Acide ascorbique/pharmacologie , Aspergillus/métabolisme , Dérivés du biphényle/composition chimique , Hydroxyanisole butylé/pharmacologie , Cations , Milieux de culture/métabolisme , Diclofenac/pharmacologie , Oedème/traitement médicamenteux , Radicaux libres , Hydrazines/composition chimique , Phénol , Rats
8.
Egyptian Journal of Pharmaceutical Sciences. 1997; 38 (1-3): 121-129
de Anglais | IMEMR | ID: emr-44534

RÉSUMÉ

Stability constants of Ni2+, Co2+, Cd2+, and Mn2+ complexes with some Schiff base ligands of isatin-semi and thiosemicarbazones, isatin S-methylhydrazine carbodithioate and ninhydrinsemi and thiosemi- carbazones have been determined potentiometrically in different media containing ratios of aquo-organic solvents [ethanol, acetone, dioxane, tetrahydrofuran, dimethyl formamide] at ionic strength u=0.04 mol. dm-3 KCl at different temperatures. The acid dissociation constants of the ligands have been also determined under identical conditions. The results obtained are discussed in terms of the molecular structure of the ligands. The solvent characteristics as well as the nature of central metal ion. It has been found that the stability constant values increase with increasing the organic solvent in the reaction medium and decrease at higher temperatures. Thermodynamic functions [delta G, delta H, delta S] were evaluated and discussed


Sujet(s)
Chélateurs/composition chimique , Température , Bases de Schiff/composition chimique , Ninhydrine/composition chimique , Hydrazines/composition chimique , Isatine
9.
Egyptian Journal of Pharmaceutical Sciences. 1997; 38 (4-6): 221-231
de Anglais | IMEMR | ID: emr-44543

RÉSUMÉ

Fusion of 6-bromo, 6,8-dibromo and 6-nitro-3-hydroxycoumarin with primary and secondary amines led to the formation of 3-aminocoumarin derivatives. Reaction of 3-hydroxycoumarin derivatives with hydrazine hydrate yielded 3-hydroazinocoumarin derivatives. Heating alpha- phenylhydrazino-beta-2-hydroxy-5-nitrocinnamic acid phenylhydrazide with acetic anhydride and hydrochloric acid gave 6-nitro-3-phenylhydrazinocoumarin


Sujet(s)
Coumarines/synthèse chimique , Coumarines/pharmacologie , Amines/composition chimique , Hydrazines/composition chimique
10.
Egyptian Journal of Chemistry. 1997; 40 (2): 129-37
de Anglais | IMEMR | ID: emr-107804

RÉSUMÉ

The electronic absorption spectra of some new azino compounds derived from hydrazine and different aldehyde and ketones are investigated in organic solvents of varying polarities. The important bands in the IR spectra and the main 1H NMR signals are assigned and discussed in relation to molecular structure. Although work on the absorption spectra of azino compounds has been reported in the literature [1-3], a series of new azino compounds derived from hydrazine and different aldehyde and ketones was prepared and in order to throw more light on their structures, these compounds were subjected to elemental analysis, spectroscopic studies and Uv-visible spectral behavior in organic solvents of varied polarity. The study included also the assignment of IR bands and 1H NMR signals by considering the effect of molecular structure on the spectral behavior


Sujet(s)
Hydrazines/composition chimique , Aldéhydes/composition chimique , Cétones/composition chimique
11.
12.
Egyptian Journal of Chemistry. 1987; 30 (2): 171-7
de Anglais | IMEMR | ID: emr-107305
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